The cost of vision loss in Canada CNIB and the Canadian
Transcription
The cost of vision loss in Canada CNIB and the Canadian
The cost of vision loss in Canada Report by Access Economics Pty Limited for the CNIB and the Canadian Ophthalmological Society The cost of vision loss in Canada CONTENTS Glossary of acronyms............................................................................................................. i Executive summary................................................................................................................ ii 1. Background ................................................................................................................... 5 1.1 Definitions..........................................................................................................................5 1.1.1 Better eye, worse eye 5 1.1.2 Severity definitions used in this report 5 1.2 Main causes of impairment ................................................................................................5 1.2.1 Age related macular degeneration (AMD) 5 1.2.2 Cataract 5 1.2.3 Diabetic retinopathy 5 1.2.4 Glaucoma 5 1.2.5 Refractive error (RE) and other causes of vision loss 5 2. Estimating prevalence .................................................................................................. 5 2.1 Population data..................................................................................................................5 2.1.1 Age, gender and growth 5 2.1.2 Ethnicity 5 2.2 Data sources for prevalence of vision loss.........................................................................5 2.2.1 Population-based eye studies 5 2.2.2 Canadian self-reported survey data 5 2.2.3 Data from Canadian journal articles and research studies 5 2.3 Prevalence rates for VL .....................................................................................................5 2.3.1 White population VL 5 2.3.2 Aboriginals and Visible Minorities (AVM) VL 5 2.3.3 Cataract-induced VL in AVM 5 2.3.4 VL caused by AMD, Glaucoma and RE in AVM 5 2.3.5 Diabetes and DR in the AVM population 5 2.3.6 Summary of VL in AVM populations 5 2.4 Summary ...........................................................................................................................5 3. Health system expenditure .......................................................................................... 5 3.1 3.2 3.3 4. Total expenditure on ‘vision care’ ......................................................................................5 Expenditure on particular eye disorders.............................................................................5 Total health system expenditure ........................................................................................5 3.3.1 Health system expenditure, top down 5 3.3.2 Health system expenditure, bottom up 5 Other financial costs .................................................................................................... 5 4.1 Productivity losses .............................................................................................................5 4.1.1 Employment participation 5 While every effort has been made to ensure the accuracy of this document, the uncertain nature of economic data, forecasting and analysis means that Access Economics Pty Limited is unable to make any warranties in relation to the information contained herein. Access Economics Pty Limited, its employees and agents disclaim liability for any loss or damage which may arise as a consequence of any person relying on the information contained in this document. The cost of vision loss in Canada 4.1.2 Absenteeism from paid and unpaid work 5 4.1.3 Presenteeism 5 4.1.4 Premature mortality 5 4.1.5 Funeral costs 5 4.2 DWL from transfers............................................................................................................5 4.2.1 Lost taxation revenue 5 4.2.2 Social security payments 5 4.2.3 Deadweight losses 5 4.3 Care and other assistance.................................................................................................5 4.4 Aids and devices ...............................................................................................................5 4.4.1 Canes and accessories 5 4.4.2 Writing aids/stationery 5 4.4.3 Variable speed tape recorders 5 4.4.4 Computer voice synthesizer software 5 4.4.5 Electronic Braille display systems 5 4.4.6 Talking time pieces 5 4.4.7 Sunglasses with non-corrective lenses 5 4.4.8 Hand held magnifiers 5 4.4.9 Video magnifiers/CCTVs 5 4.4.10 Screen magnification software 5 4.4.11 Other aids for the sight impaired 5 4.4.12 Summary of aids and devices 5 4.5 Summary of other financial costs.......................................................................................5 5. Burden of disease ......................................................................................................... 5 5.1 Willingness to pay and the value of a life year ...................................................................5 5.1.1 Measuring burden: DALYs, YLLs and YLDs 5 5.1.2 Willingness to pay and the value of a statistical life year 5 5.2 Burden of disease from vision loss ....................................................................................5 5.2.1 Disability weights 5 5.2.2 Deaths from VL 5 5.2.3 Years of life lost due to disability 5 5.2.4 Years of life due to premature death 5 5.3 Total DALYs due to VL ......................................................................................................5 6. Summary........................................................................................................................5 Appendix A: EDPRG prevalence tables ............................................................................... 5 Appendix B: Prevalence projections by age, gender and disease .................................... 5 References .............................................................................................................................. 5 The cost of vision loss in Canada FIGURES Figure 1-1: Vision problems among Canadian seniors (% of age group) Figure 1-2: Prevalence of AMD by age and gender in whites (% population) Figure 1-3: Prevalence of cataract by age and gender in whites (% population) Figure 1-4: Rates of cataract surgery by age Figure 1-5: Prevalence of DR by age and gender in whites (% population) Figure 1-6: Prevalence of glaucoma by age and gender in whites(% population) Figure 1-7: Prevalence of myopia by age and gender in whites (% population) Figure 1-8: Prevalence of hyperopia by age and gender in whites (% population) Figure 1-9: Prevalence of hyperopia across countries by age, gender and source study (% population) Figure 1-10: Prevalence of myopia across countries by age, gender and source study (% population) Figure 2-1: Prevalence and incidence approaches to cost measurement Figure 2-2: Canadian population by age (’000 people), 2006 and 2031 Figure 2-3: White and AVM populations, 2006-2032 (% total) Figure 2-4: Aboriginals and Visible Minorities, 1981-2017, selected years (% population) Figure 2-5: Age distribution of non-white males (% population), 2001 Figure 2-6: Age distribution of non-white females (% population), 2001 Figure 2-7: Ethnic composition of Canadian population compared to Australia’s Figure 2-8: Prevalence of seeing disabilities by age and gender (2001) Figure 2-9: Uncorrected VL, by ethnicity, age and gender (% population) Figure 2-10: Under corrected VL from myopia, by ethnicity, age and gender (% population) Figure 2-11: Under corrected VL from hyperopia, by ethnicity, age and gender (% population) Figure 2-12: Canadians unable to see clearly at any distance or at all, by ethnicity, age and gender (% population) Figure 2-13: Cataract prevalence, by ethnicity, age and gender (% population) Figure 2-14: Glaucoma, by ethnicity, age and gender (% population) Figure 2-15: Causes of VL in Prince George, Canada Figure 2-16: Myopia in Chinese children in Canada and Hong Kong Figure 2-17: Causes of blindness by ethnicity (US) Figure 2-18: Probability of developing VL after contracting selected diseases, by ethnicity Figure 2-19: Prevalence rates of VL, by ethnicity and cause, 2007 Figure 2-20: Prevalence of VL, by cause, 2007-2032 Figure 2-21: Prevalence of VL by gender, 2007 to 2032 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 The cost of vision loss in Canada Figure 2-22: Projections of VL, by ethnicity, 2007 to 2032 Figure 2-23: Relative share of total VL, by ethnicity, 2007 to 2032 Figure 3-1: Canadian health system expenditure, 2007 (% of total) Figure 3-2: Expenditure on vision care, Canada, 1975-2007 Figure 4-1: DWL of taxation Figure 4-2: Comparison of assistance with activities of daily living between study groups Figure 5-1: Loss of wellbeing due to VL (DALYs), by age and gender, 2007 Figure 6-1: Financial costs of VL, by type of cost (% total) Figure 6-2: Financial costs of VL, by bearer (% total) 5 5 5 5 5 5 5 5 5 TABLES Table 2–1: Canadian population projections, males (‘000), 2006-2031, selected years Table 2–2: Canadian population projections, females (‘000), 2006-2031, selected years Table 2–3: Ethnic composition of Canadian population (% total), 2001 Table 2–4: Prevalence of diabetes, by age and gender, 2005 (%) Table 2–5: CCHS prevalence of eye diseases in AVM Table 2–6: Causes of blindness in CNIB clients (2007) Table 2–7: Prevalence of POAG among the Eskimo (%) Table 2–8: Prevalence of diabetes among Canadian Aboriginal peoples (1991) Table 2–9: Prevalence of blindness by cause, 2006 to 2031 (% population) Table 2–10: causes of VL, by disease, in white populations Table 2–11: Prevalence of VL due to AMD, by severity (% of age group) Table 2–12: Prevalence rates for VL from cataracts, by age and severity (%) Table 2–13: Prevalence rates for vision impairment (<6/12) from DR, and proportion by stage of vision loss Table 2–14: Proportion of people with glaucoma by age and severity (%) Table 2–15: Prevalence rates for VL from RE, by age and severity (%) Table 2–16: Estimated VL prevalence in Canadian whites by disease and age Table 2–17: Prevalence of VL in US whites with cataracts (2000) Table 2–18: Prevalence of VL in US blacks with cataracts (2000) Table 2–19: Prevalence of VL in US Hispanics with cataracts (2000) Table 2–20: Prevalence of VL in US ‘Other’ with cataracts (2000) Table 2–21: Relative risk of developing VL from cataracts, by race Table 2–22: Prevalence of VL in whites with cataract, by age Table 2–23: Prevalence of VL in non- whites with cataract, by age Table 2–24: Prevalence of cataract-induced VL in Canadian AVM, by age 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 The cost of vision loss in Canada Table 2–25: Prevalence of eye diseases by ethnicity, US, 2000 Table 2–26: Causes of VL by ethnicity Table 2–27: Prevalence of VL, by ethnicity and cause, US, 2000 Table 2–28: Prevalence (%) of VL within specified diseases, by ethnicity Table 2–29: Relative risk of VL by eye disease, non-whites to whites Table 2–30: Prevalence of eye diseases in whites Table 2–31: Fraction of whites with each eye disease who have VL, by age and gender (%) Table 2–32: prevalence of VL within disease groups, non-whites Table 2–33: Prevalence of VL in AVM Table 2–34: Under corrected VL in AVM Table 2–35: Prevalence of VL from DR within diabetic AVM groups Table 2–36: Prevalence of diabetes in AVM population, 2005 (%) Table 2–37: Estimated prevalence of DR-induced VL in AVM Table 2–38: Prevalence of VL in AVM by age, gender and disease Table 2–39: Prevalence of VL, by cause and ethnicity, 2007 Table 2–40: All vision loss, by age, gender and ethnicity, 2007 Table 2–41: Cataract vision loss, by age, gender and ethnicity, 2007 Table 2–42: DR vision loss, by age, gender and ethnicity, 2007 Table 2–43: Glaucoma vision loss, by age, gender and ethnicity, 2007 Table 2–44: AMD vision loss, by age, gender and ethnicity, 2007 Table 2–45: RE/Other vision loss, by age, gender and ethnicity, 2007 Table 3–1: Total expenditure on certain eye procedures, 2004-05 Table 3–2: Drug expenditure on nervous system and sense organ disorders, 1998 Table 3–3: Expenditure on nervous system and sense organ disorders (1998) Table 3–4: Frequency of selected hospital procedures (2001) Table 3–5: Rebates for certain ophthalmological procedures in Ontario (2006) Table 3–6: Average treatment costs for neovascular AMD (2005) Table 3–7: Estimated VL health system expenditure (top down), 2007 Table 4–1: Estimated AWE, by age and gender, 2007 Table 4–2: percentage of population employed, by age and gender Table 4–3: Provincial sales taxes Table 4–4: Income sources (CNIB) Table 4–5: VL-related social security payments and beneficiaries Table 4–6: Excess usage of social security payments Table 4–7: Annual direct AMD non-medical related utilisation costs per person (2005$) Table 4–8: Canes/accessories for the blind (2000-01$) Table 4–9: Writing and stationery items (2000-01$) Table 4–10: Talking time pieces (2000-01$) 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 The cost of vision loss in Canada Table 4–11: Sunglasses with non-corrective lenses (2000-01$) Table 4–12: Hand held magnifiers (2000-01$) Table 4–13: Other stationery (2000-01$) Table 4–14: Large button telephones (2000-01$) Table 4–15: Summary of aids and devices (2000-01$) Table 4–16: Estimates of additional aids and devices Table 4–17: Summary of other financial costs of VL, 2007 Table 5–1: Value of a statistical life in Canadian studies ($ million) Table 5–2: Estimated years of healthy life lost due to disability (YLD), 2007 (DALYs) Table 5–3: Years of life lost due to premature death (YLL) due to VL, 2007 Table 5–4: Net cost of lost wellbeing, $million, 2007 Table 6–1: VL, total costs by type of cost and bearer, 2007 5 5 5 5 5 5 5 5 5 5 5 5 The cost of vision loss in Canada GLOSSARY OF ACRONYMS AMD AVM AWE BMES CACS CCHS CCTV CERA CIHI CNIB COS DALY DR DWL EDPRG GST HST ICES MVIP NGS NHEX NPHS PALS POAG PST RE UK US UV VL VSL(Y) age related macular degeneration Aboriginal and Visible Minorities Average Weekly Earnings Blue Mountains Eye Study Comprehensive Ambulatory Classification System Canadian Community Health Survey closed circuit television Centre for Eye Research Australia Canadian Institute for Health Information CNIB Canadian Ophthalmological Society Disability Adjusted Life Year diabetic retinopathy deadweight loss Eye Disease Prevalence Research Group Goods and Services Tax Harmonized Sales Tax Institute for Clinical Evaluative Sciences Melbourne Visual Impairment Project National Grouping System National Health Expenditure database National Population Health Survey Participation and Activity Limitation Survey Primary Open Angle Glaucoma Provincial Sales Taxes refractive error United Kingdom United States ultraviolet vision loss Value of a Statistical Life (Year) i The cost of vision loss in Canada EXECUTIVE SUMMARY This report estimates the cost of vision loss (VL) in Canada, utilising a prevalence-based approach. Direct health system expenditures on visually impairing eye conditions are included, as well as other financial costs (such as productivity losses) and the value of the loss of healthy life (measured in Disability Adjusted Life Years or DALYs). Prevalence of vision loss A variety of data sources were used to construct a model of Canadian VL by age, gender, ethnicity, severity and type. In 2007, there were an estimated 816,951 Canadians with VL. Of this total, 780,534 (95.5%) were white and 36,416 (4.5%) were Aboriginals and Visible Minorities (AVM). ‘Refractive Error and Other’ is the main source of VL for the white population (68.1% of the total), and cataract is the main cause of VL in AVM (36.1% of the total)1. For whites, the second largest source of VL is cataract (15.5%) and, for the AVM population, DR is the second largest source (24.4% of the total). AVM have lower prevalence of VL for all diseases other than DR, largely due to lower prevalence of eye diseases at equivalent ages to whites, a younger age profile, and less likelihood of developing VL once they have contracted a given eye disease. PREVALENCE OF VL, BY CAUSE AND ETHNICITY, 2007 All ethnicities White AVM Number % total Number % total Number % total 1 AMD Cataract DR Glaucoma RE/Other 89,241 133,836 29,920 24,937 539,236 10.9% 16.4% 3.7% 3.1% 66.0% 84,641 120,685 20,992 22,565 531,650 10.8% 15.5% 2.7% 2.9% 68.1% All VL 817,171 100.0% 780,534 100.0% 4,380 13,151 8,928 2,373 7,586 36,417 12.0% 36.1% 24.5% 6.5% 20.8% 100.0% ‘Other’ represents minor diseases – ie, not the ‘big five’ of cataract, diabetic retinopathy (DR), age-related macular degeneration (AMD), glaucoma, or refractive error (RE). ‘Other’ diseases have not been the subject of population eye health studies. ii The cost of vision loss in Canada PREVALENCE RATES OF VL, BY CAUSE AND ETHNICITY, 2007 3.5% All races White AVM 3.0% 3.0% 2.5% Prevalence (%) 2.5% 2.0% 2.0% 1.6% 1.5% 1.0% 0.4% 0.1% 0.5% 0.1% 0.1% 0.3% 0.2% 0.1% 0.1% 0.0% 0.1% 0.6% 0.3% 0.5% 0.0% AMD Cataract DR 0.1% Glaucoma RE/Other All VI The prevalence of VL is projected to almost double in absolute numbers, and increase from 2.5% of the population in 2007 to 4.0% in 2032. VL affects women more than men, reflecting greater longevity in females. In 2007, females accounted for 58.4% of VL; by 2032, this will have fallen slightly to 56.3%. Despite the fact that the AVM share of the total population is rapidly increasing, the increase in this group’s share of VL at the end of the projection period is less than commensurate, partly due to AVM having a considerably younger age profile than the white population with no substantial aging over the forecast period. PREVALENCE OF VL, BY CAUSE, 2007-2032 4.5% 4.0% All VI Cataracts DR Glaucoma AMD RE/Other 3.5% 2.5% 2.0% 1.5% 1.0% 0.5% 2032 2031 2030 2029 2028 2027 2026 2025 2024 2023 2022 2021 2020 2019 2018 2017 2016 2015 2014 2013 2012 2011 2010 2009 2008 0.0% 2007 Prevalence (%) 3.0% iii The cost of vision loss in Canada Costs In 2007, the financial cost of VL was $15.8 billion. Of this: $8.6 billion (54.6%) was direct health system expenditure; $4.4 billion (28.0%) was productivity lost due to lower employment, absenteeism and premature death of Canadians with VL; $1.8 billion (11.1%) was the DWL from transfers including welfare payments and taxation forgone; $0.7 billion (4.4%) was the value of the care for people with VL; and $305 million (1.9%) was other indirect costs such as aids and home modifications and the bring-forward of funeral costs. Additionally, the value of the lost wellbeing (disability and premature death) was a further $11.7 billion. VL, TOTAL COSTS BY TYPE OF COST AND BEARER, 2007 Individuals Family/ Friends Federal Government Provincial Governments Society/ Other Employers Total Total cost ($ million) Burden of disease Health system costs Productivity costs Carer costs Other Indirect costs Deadweight losses Transfers Total financial costs Total costs including burden of disease 11,710 1,499 2,847 0 61 0 -917 3,490 15,200 0 0 0 413 62 0 0 474 0 388 886 218 0 0 917 2,409 0 5,670 619 0 61 0 0 6,350 0 0 80 0 61 0 0 141 0 1,081 0 62 61 1,757 0 2,960 11,710.4 8,637.9 4,431.4 692.8 304.9 1,757.0 0 15,824 474 2,409 6,350 141 2,960 27,534 Cost per person with visual impairment ($) 14,334 0 0 0 0 0 14,334 Health system costs 1,835 0 475 6,941 0 1,323 10,573 Productivity costs Carer costs Other Indirect costs Deadweight losses Transfers Total financial costs Total costs including burden of disease 3,485 0 74 0 -1,122 4,272 0 505 76 0 0 581 1,084 267 0 0 1,122 2,948 757 0 74 0 0 7,773 98 0 74 0 0 172 0 76 74 2,151 0 3,624 5,424 848 373 2,151 0 19,370 18,606 581 2,948 7,773 172 3,624 33,704 Burden of disease In per capita terms, this amounts to a financial cost of $19,370 per person with VL per annum. Including the value of lost wellbeing, the cost is $33,704 per person per annum. iv The cost of vision loss in Canada FINANCIAL COSTS OF VL, BY TYPE OF COST (% TOTAL) DWL 11.1% Indirect Costs 1.9% Carer Costs 4.4% Productivity Costs 28.0% Health System Costs 54.6% Individuals with VL bear 22.1% of the financial costs, and their families and friends bear a further 3.0%. Federal government bears 15.2% of the financial costs (mainly through taxation revenues forgone and welfare payments). Provincial governments bear 40.1% of the costs, reflecting the nature of Canada’s Federal system, while employers bear 0.9% and the rest of society bears the remaining 18.7%. If the burden of disease (lost wellbeing) is included, individuals bear 55.2% of the costs and Provincial governments bear 23.1% while the Federal government bears a lesser 8.7%, with family and friends 1.7%, employers 0.5% and others in society 10.8%. FINANCIAL COSTS OF VL, BY BEARER (% TOTAL) Society/Other 18.7% Individuals 22.1% Employers 0.9% Family/Friends 3.0% Federal Government 15.2% Provincial Governments 40.1% v The cost of vision loss in Canada Finally, an important finding from this analysis was the observation that, for an advanced Western nation, Canada has a serious deficiency in eye health data. CNIB’s Health Economic Statement (http://www.costofblindness.org/media/health-state.asp) observes that, with respect to blindness and vision loss, there is ‘strong argument for saying that Canada has the worst record of supporting research of all the G8 countries’. The importance of good eye health to Canadians is shown from survey data in the same document revealing that two-thirds of Canadians would cash in all their savings or sell everything they owned to save their eyesight. With a rapidly aging population, it is high time for a Canadian population eye health study to monitor incidence, prevalence and morbidity outcomes and economic impacts more robustly in the future. Access Economics 12 December 2008 vi The cost of vision loss in Canada 1. BACKGROUND This report estimates the cost of vision loss (VL) in Canada, utilising a prevalence-based approach. Direct health system expenditures on visually impairing eye conditions are included, as well as other financial costs (such as productivity losses) and the value of the loss of healthy life (measured in Disability Adjusted Life Years or DALYs). 1.1 DEFINITIONS Statistics Canada (2004a) reported that the majority (51%) of Canadians had some form of ‘vision problem’ in 2003, while Statistics Canada (2001) found that that 2.5% had a ‘visual disability’. A ‘vision problem’ is not considered a visual disability if it can be corrected (eg, with glasses or contact lenses for refractive error - RE). Figure 1-1 shows the differences between the two categories within age and gender cohorts for Canadian seniors (people aged 65 years or older), where prevalence is understandably higher (70%-90%). FIGURE 1-1: VISION PROBLEMS AMONG CANADIAN SENIORS (% OF AGE GROUP) 100% 90% 80% Prevalence (%) 70% 60% Male, uncorrected 50% Male, corrected 40% Female, uncorrected Female, corrected 30% 20% 10% 80+ 75 to 79 70 to 74 65 to 69 All Seniors 0% Y e a rs o f a ge Source: Statistics Canada (2004a). In this report, the term ‘vision loss’ rather than ‘visual disability’ will be used. Vision loss is broadly defined as a limitation in one or more functions of the eye or visual system, most commonly impairment of visual acuity (sharpness or clarity of vision), visual fields (the ability to detect objects to either side or above or below the direction in which the person is looking) and colour vision. 1 The cost of vision loss in Canada Normal vision is recorded as 20/20 in the Imperial system used in Canada (6/6 in metric), which means that a person can see at 20 feet (6 meters) what a person with normal vision can see at 20 feet. Degrees of VL are measured similarly, where the first number in the measure is the furthermost distance at which the person can clearly see an object and the second number is the distance at which a person with normal vision could see the same object. For example, 20/40 vision means that the person can clearly see at 20 feet (but not more) an object that a person with unimpaired vision could see at 40 feet (but not more). The Blind Persons Regulations, Consolidated Regulations of Canada 1978 (Chapter 371A)2 states that ‘a person shall be considered legally blind whose central acuity does not exceed 20/200 in the better eye with correcting lenses’. This means that if a person with their glasses on can see the big 'E' on a Snellen eye chart, but none of the other optotypes, for legal purposes they are considered blind and are eligible for certain government tax credits as well as concessions from some retailers and other service providers. The Canadian definition of legal blindness also includes ‘or a visual field extent of less than 20 degrees in diameter horizontally’. 1.1.1 BETTER EYE, WORSE EYE VL can differ from one eye to the other (asymmetrical vision loss). As a result of this, prevalence rates can be reported for either the better or the worse eye in terms of the extent of vision loss. Asymmetrical vision loss, however, has little impact on function or disability, and indeed, it is often only when vision loss becomes bilateral that it is identified and treated. When reporting prevalence rates, better eye measures would provide conservative estimates, while worse eye measures may tend to overstate costs and impairment. In this study, the conservative approach has thus been to report VL prevalence for the better eye. SEVERITY DEFINITIONS USED IN THIS REPORT 1.1.2 Best corrected visual acuity (BCVA) is defined as the best possible vision a person can achieve with corrective lenses measured in terms of Snellen lines on an eye chart. Common definitions for visual acuity used in Canada (Jutai et al, 2006), and in this report are as follows. Blindness is defined as BCVA of 20/200 or worse (≤6/60) in the better-seeing eye. Vision loss is defined as BCVA less than 20/40 (<6/12) in the better-seeing eye. It thus comprises blindness and low vision. Low vision is defined as VL that is not blindness, and is categorized as: mild VL – BCVA worse than 20/40 (<6/12) but better than or equal to 20/60 (6/18) in the better-seeing eye; and 2 moderate VL – BCVA worse than 20/60 (<6/18) but better than or equal to 20/200 (6/60) in the better-seeing eye. http://www.amdcanada.com/template.php?section=4&lang=eng&subSec=3d&content=4_3 (accessed 28 March 2008) 2 The cost of vision loss in Canada 1.2 MAIN CAUSES OF IMPAIRMENT 1.2.1 AGE RELATED MACULAR DEGENERATION (AMD) AMD is an incurable eye disease and a leading cause of blindness in elderly people. The macula is the part of the retina that enables central vision and the seeing of fine detail. Damage to the macula is characterized by a ‘black spot’ – losing the centre of the picture. In ‘early AMD,’ small yellow deposits called drusen form under the macula. Vision is usually lost with more advanced stages of AMD. There are two types of ‘late AMD’. Dry (geographic/atrophic): In around one third of cases of late AMD, the macula thins. Vision loss is directly related to the location and amount of retinal thinning, but the progress of dry AMD is slower than that of the ‘wet’ type. There is no known treatment or cure for the ‘dry’ type of AMD. Wet (exudative/neovascular): Two thirds of those with late AMD have this type. Abnormal blood vessels grow under the retina and macula; these vessels bleed and leak fluid, causing the macula to bulge or lift up. Vision loss may be rapid and severe. Thermal laser surgery may be used in the early stages and may prevent severe eye damage for some patients. Photodynamic laser therapy with verteporfin provides an improvement over thermal laser treatment, but does not preclude recurrence, so that at best it slows the rate of vision loss. Causes of AMD are not well understood, but may include age and a genetic component, with family history increasing the risk of AMD three to four times. People who smoke are twice as likely to develop AMD. People who have a family history of AMD and smoke are up to 144 times more likely to develop the disease. In summary, in most cases there is no effective prevention of or treatment for AMD. Because AMD is painless, usually progresses slowly and generally occurs in one eye first, it may be difficult to self-detect AMD early (Access Economics, 2006). Current treatments for AMD, such as photodynamic therapy, are limited both in terms of their ability to retard progression of disease and thus loss of vision, as well as only being effective for a proportion of people with neovascular AMD. However, emerging therapies have the potential to enhance the efficacy and coverage of treatment options for people with AMD. Anti-angiogenesis is a treatment that aims to block the process of angiogenesis in neovascular AMD. Theoretically this will retard progression of neovascular AMD and reduce its recurrence. Anti-angiogenesis treatments include: o Pegaptanib (Macugen). This requires six weekly injections in the affected eye over a period of at least two years. Pegaptanib has been shown to retard the progression of wet AMD. o Ranibizumab (Lucentis) is new treatment, shown to be effective in both retarding the progression of wet AMD and restoring some vision to a significant number of patients. o Bevacizumab (Avastin) has been fairly widely used ‘off label’ for AMD, although it is not indicated for this condition. As yet, no extensive head to head clinical trials have been conducted comparing bevacizumab and ranibizumab with respect to both safety and efficacy. Figure 1-2 shows the prevalence of AMD by gender among whites, based on an international meta-analysis of these ethnicities by the Eye Disease Prevalence Research Group – EDPRG (Congdon et al, 2004a). Details of the source studies used by the EDPRG are provided in 3 The cost of vision loss in Canada Appendix A, and include studies from the United States (US), West Indies, Australia and the Netherlands. FIGURE 1-2: PREVALENCE OF AMD BY AGE AND GENDER IN WHITES (% POPULATION) 14% 12% White Female Prevalence (%) 10% 8% White Male 6% 4% 2% 85+ 80-84 Years of age 75-79 70-74 65-69 60-64 55-59 50-54 0% Note: See Appendix A for underlying data. Source: Congdon et al (2004a) and Access Economics (2006). 1.2.2 CATARACT A cataract is a cloudy area in the eye's lens that forms when proteins clump together. Over time, the cataract may grow larger and cloud more of the lens, making it hard to see. The most common symptoms are blurry vision, problems with light, ‘faded’ colours, double or multiple vision and the need for frequent changes in glasses or contact lenses. The four main types of cataract are age related (most common), congenital, secondary (eg, due to diabetes or steroid use) and traumatic (eg, due to eye injury). Causes of cataract are still uncertain, although age, smoking, diabetes and ultraviolet (UV) exposure have been shown to increase risk. Detection is through an eye examination including a visual acuity test (eye chart test) and pupil dilation (where the pupil is widened with eye drops to allow the eye care professional to see more of the lens and look for other eye problems). Cataract surgery may be indicated to improve vision, with the cloudy lens removed and replaced with a substitute lens. Surgery is safe and very effective, with almost all people having better vision and improved quality of life afterward, and only a small percentage experiencing complications such as infection, bleeding or inflammation. Cataract surgery is generally performed as same-day surgery without general aesthetic, with a six week total recovery period. 4 The cost of vision loss in Canada Figure 1-3 shows the prevalence of cataract by age, gender and ethnicity. FIGURE 1-3: PREVALENCE OF CATARACT BY AGE AND GENDER IN WHITES (% POPULATION) 80% 70% White Female 60% White Male Prevalence (%) 50% 40% 30% 20% 10% 80+ 75-79 Years of age 70-74 65-69 60-64 55-59 50-54 40-49 0% Note: See Appendix A for underlying data. Source: Congdon et al (2004a) and Access Economics (2006). 5 The cost of vision loss in Canada Taylor (2001) shows that, in Australia, rates of cataract surgery double with each decade of life. Figure 1-4 shows rate of cataract by age group. While younger people have lower rates of cataract surgery than older cohorts, because there are fewer people in the oldest cohorts3, the average age of cataract surgery in Canada is 74 years4. Conversely, while surgery rates increase in older cohorts, prevalence of cataract increases faster still, leading to higher rates of VL in the oldest of the old. FIGURE 1-4: RATES OF CATARACT SURGERY BY AGE Source: Taylor (2001). 1.2.3 DIABETIC RETINOPATHY Diabetic retinopathy (DR) is a complication of diabetes mellitus, usually affecting both eyes, wherein microaneurysms develop on the tiny blood vessels inside the retina. As the disease progresses, some blood vessels that nourish the retina are blocked, causing vision loss through either proliferative retinopathy or macular edema. Left: Normal vision. Right: The same scene as it might be viewed by a person with DR. DR often has no early symptoms. Sometimes the person sees specks of blood, or spots, ‘floating’ in their vision. Diagnosis can be made via a visual acuity test (eye chart test), dilated eye examination, retinal photography and/or fluorescein angiogram. Macular edema 6 3 There are over ten times as many Canadian septuagenarians as nonagenarians. 4 Canadian Ophthalmological Society, correspondence of 11 April 2008. The cost of vision loss in Canada is treated with focal laser surgery, which stabilizes vision and reduces the risk of vision loss by 50%. Proliferative retinopathy is treated with scatter laser surgery that, while it can worsen peripheral, colour and/or night vision, can save the rest of a person’s sight. If bleeding is severe and persistent, a vitrectomy may be necessary, where blood and gel are removed from the centre of the eye and replaced with a salt solution, under local or general anesthetic. Although both laser treatment and vitrectomy can effectively reduce vision loss they do not cure DR, and the patient remains at risk for new bleeding. Multiple treatments may be necessary. To prevent the onset and progression of DR (and the need for surgery), people with diabetes should control their levels of blood sugar, blood pressure and blood cholesterol. Early diagnosis and treatment can prevent almost all severe vision loss. The earlier treatment is received, the more likely it is to be effective. Prevalence is shown in Figure 1-5. 7 The cost of vision loss in Canada FIGURE 1-5: PREVALENCE OF DR BY AGE AND GENDER IN WHITES (% POPULATION) 8% 7% 6% Prevalence (%) 5% 4% 3% White Female 2% White Male 1% Years of age 75+ 65-74 50-64 40-49 18-39 0% Note: See Appendix A for underlying data. Source: Congdon et al (2004a) and Access Economics (2006). 1.2.4 GLAUCOMA Glaucoma is a group of diseases that, while initially asymptomatic, can damage the eye's optic nerve and result in blindness. The optic nerve comprises nerve fibers that connect the retina with the brain. In the front of the eye is a space called the anterior chamber – clear fluid flows in and out of this space, leaving the chamber at the angle where the cornea and iris meet. When the fluid reaches the angle, it flows through a spongy meshwork, like a drain, and leaves the eye. Primary open-angle glaucoma (POAG), the most common type, occurs when, for unknown reasons, the fluid passes too slowly through the meshwork drain. As the fluid builds up, the pressure inside the eye rises. Unless the pressure at the front of the eye is controlled, it can damage the optic nerve and cause vision loss. Although people can see objects clearly in front of them, they miss things to the side and out of the corner of their eye. Peripheral vision may deteriorate without treatment, like looking through a tunnel, until there is no vision left. Left: Normal vision. Right: The same scene as it might be viewed by a person with glaucoma. 8 The cost of vision loss in Canada Other less common types of glaucoma include: Closed-angle glaucoma, in which the fluid at the front of the eye is blocked from reaching the angle, resulting in a sudden increase in pressure, pain, redness and blurred vision. Immediate (medical emergency) laser surgery is required to clear the blockage and protect sight. Congenital glaucoma, occurring in children born with defects in the angle of the eye that slow fluid drainage, causing cloudy eyes, sensitivity to light and excessive tearing. Prompt surgery provides an excellent chance of saving vision. Secondary glaucoma, which develops as a complication of other medical conditions, such as surgery, advanced cataract, eye injuries, certain eye tumours, uveitis (eye inflammation), diabetes or the use of corticosteroid drugs. Treatment includes medicines and laser or conventional surgery. Increased risk for glaucoma occurs with age, family history and ethnicity. Glaucoma is detected through an eye examination including visual acuity, visual field, tonometry and optic nerve examination. Although there is no cure for glaucoma, early diagnosis and treatment may help protect eyes against serious vision loss and blindness. Treatments include: Eye drops (very common) – eye drops taken several times a day can lower pressure by helping fluid drain from the eye or causing the eye to make less fluid. Rare side effects include headaches or eye irritation. Laser surgery (‘laser trabeculoplasty’) – helps fluid drain from the eye by burning holes in the meshwork with a high-energy light beam. The effects of laser surgery wear off so that, after two years, the pressure increases again in more than half of all patients. Repeating laser surgery is often not useful. Conventional surgery – can make a new opening for the fluid to leave the eye. Such surgeries are often performed after eye drops and laser surgery have failed to control pressure. Surgery is around 80-90% effective at lowering pressure. However, if the new drainage opening closes, a second operation may be needed. Conventional surgery works best in the absence of other previous eye surgery. Possible side effects of glaucoma surgery include cataract, inflammation or infection inside the eye, and swelling of blood vessels behind the eye – all of which are treatable. In some cases, vision may worsen after surgery. 9 The cost of vision loss in Canada FIGURE 1-6: PREVALENCE OF GLAUCOMA BY AGE AND GENDER IN WHITES(% POPULATION) 8% 7% White Female Prevalence (%) 6% 5% White Male 4% 3% 2% 1% 80+ 75-79 Years of age 70-74 65-69 60-64 55-59 50-54 40-49 0% Note: See Appendix A for underlying data. Source: Congdon et al (2004a) and Access Economics (2006). 1.2.5 REFRACTIVE ERROR (RE) AND OTHER CAUSES OF VISION LOSS A large part of remaining vision loss is caused by RE. Less common conditions such as neuro-ophthalmic disorders, retinitis pigmentosa and other retinal conditions account for the remaining prevalence of VL and blindness. As noted above, RE is the most frequent yet most easily correctible source of eye problems in Canada, occurring when optical defects result in light not focusing properly on the retina. Myopia (near-sightedness with blurry distant vision) and hyperopia (farsightedness with close objects blurry) are the most well-known RE. Most infants have some degree of hyperopia, although vision usually normalizes by six years of age. Most myopia occurs later during adolescence. The extent of RE is measured in diopters. Other common forms of REs include astigmatism (uneven focus) and presbyopia (age related problem with near focus). Myopia is a very common disorder. Prevalence is greater in women through age 60, after which rates become more comparable between genders. Myopia affects more whites than other races, and is generally less frequent with age, Hyperopia is less common, but prevalence generally increases with age. It is also most frequent in Whites. Prevent Blindness America (2002:12) Almost all RE can be corrected by eyeglasses or contact lenses. Refractive surgery is another alternative treatment, but one not without risk. Figure 1-7 and Figure 1-8 highlight that RE is less common in males than females. Myopia tends to decrease with age, whereas hyperopia increases. (Older black males have 10 The cost of vision loss in Canada significantly less of either condition than other groups – hyperopia is over 18 times more prevalent in older white females than equally aged black males.) FIGURE 1-7: PREVALENCE OF MYOPIA BY AGE AND GENDER IN WHITES (% POPULATION) 50% 45% 40% White Female 35% White Male Prevalence (%) 30% 25% 20% 15% 10% 5% 80+ 75-79 Years of age 70-74 65-69 60-64 55-59 50-54 40-49 0% Note: See Appendix A for underlying data. Source: Congdon et al (2004a) and Access Economics (2006). Note: Myopia = (-1.00 diopters or worse). FIGURE 1-8: PREVALENCE OF HYPEROPIA BY AGE AND GENDER IN WHITES (% POPULATION) 30% White Female 25% White Male Prevalence (%) 20% 15% 10% 5% 80+ 75-79 Years of age 70-74 65-69 60-64 55-59 50-54 40-49 0% Note: See Appendix A for underlying data. Source: Congdon et al (2004a) and Access Economics (2006). Note: Hyperopia = (+3.00 diopters or worse). 11 The cost of vision loss in Canada RE is the most common source of VL in Western countries; Figure 1-9 and Figure 1-10 show that population-based eyes studies demonstrate little variance in the prevalence of hyperopia and myopia in white populations across countries with similar cultures and income levels. 12 The cost of vision loss in Canada FIGURE 1-9: PREVALENCE OF HYPEROPIA ACROSS COUNTRIES BY AGE, GENDER AND SOURCE STUDY (% POPULATION) Prevalence of hyperopia of +3 diopters or greater in white persons (A) and black and Hispanic persons (B). BES= Baltimore Eye Study; BDES=Beaver Dame Eye Study; BMES=Blue Mountains Eye Study; RS=Rotterdam Study; Melbourne VIP = Melbourne Visual Impairment Project; Proyecto VER=Vision Evaluation and Research. Source: Congdon et al (2004b). 13 The cost of vision loss in Canada FIGURE 1-10: PREVALENCE OF MYOPIA ACROSS COUNTRIES BY AGE, GENDER AND SOURCE STUDY (% POPULATION) Prevalence of myopia of -1 diopter or less in white persons (A) and black and Hispanic persons (B). BES= Baltimore Eye Study; BDES=Beaver Dame Eye Study; BMES=Blue Mountains Eye Study; RS=Rotterdam Study; Melbourne VIP = Melbourne Visual Impairment Project; Proyecto VER=Vision Evaluation and Research. Source: Congdon et al (2004b). 14 The cost of vision loss in Canada 2. ESTIMATING PREVALENCE Prevalence approaches to cost estimation, for a given health condition, measure the number of people with that given condition (in this case VL) in a base period (in this case calendar year 2007) and the costs associated with treating them, as well as other financial and nonfinancial costs (productivity losses, carer burden, loss of quality of life) in that year, due to the condition. This report adopts a prevalence approach to cost measurement rather than an incidence approach, as the data sources lend themselves to utilization of such an approach, and for consistency with other studies of the cost of VL (eg, in Australia, Japan and the US). Figure 2-1 depicts the difference between a prevalence approach (areas A+B+C in Figure 2-1) and an incidence approach, the latter estimating the present value of the lifetime costs of new cases of VL in 2005 (area C plus the present value of C* in Figure 2-1). Consider person A, who first experienced VL and its impacts in 1990 and continued to experience them until death in 2005. This person would be included in a prevalence approach (but not in an incidence approach), although only the costs incurred in 2005 would be included (ie, A but not A*, where A includes the present value of premature mortality costs if the death was premature). Person B developed VL during the late 1990s and experiences impairment and its impacts through to 2008 (with costs of B+B*+B**, shaded in blue); she also would be counted (but only costs of B) using a prevalence approach, but not using an incidence approach. Person C (shaded in red) is newly diagnosed with VL in 2005 and his costs in 2005 (C) would be included in a prevalence approach but not future costs (C*). FIGURE 2-1: PREVALENCE AND INCIDENCE APPROACHES TO COST MEASUREMENT 1990 2006 2010 To estimate the number of cases of VL in the population, epidemiological data on prevalence rates are applied to population data. Ideally for projections, the number of cases of VL should be stratified by gender, age, ethnicity, severity (mild and moderate VL and blindness) and cause (AMD, cataract, DR, glaucoma, RE and ‘other’). A first step is thus to assimilate population data by gender, age and ethnicity, for 2007 and subsequent years (next section). 2.1 POPULATION DATA 2.1.1 AGE, GENDER AND GROWTH Statistics Canada (2006) reports that Canada has the second youngest population in the G85. In 2006, around one in seven Canadians (13.7%)6 was aged 65 years or older and Statistics Canada (2006) projects that by 2031 these ‘senior citizens’ will account for around 5 The Group of Eight represents the world’s largest industrialised economies: US, UK, Russia, France, Germany, Italy, Japan and Canada. 6 Statistics Canada 2006 Census Online, www.statcan.ca (Cat, No, 97-551-XCB2006005). 15 The cost of vision loss in Canada one quarter of the population (Figure 2-2)7. Thus, as many eye diseases are age related, the overall prevalence of VL will increase over the medium term. These projections were compiled using data from the 2001 Census. Although 2006 Census data have recently become available for that year, population projections by five year age-gender cohorts are not yet provided by Statistics Canada from the 2006 Census. Accordingly, this report uses Statistics Canada’s existing projections8. FIGURE 2-2: CANADIAN POPULATION BY AGE (’000 PEOPLE), 2006 AND 2031 3,000 2006 2031 2,500 Persons ('000) 2,000 1,500 1,000 500 100+ 95–99 90–94 85–89 80–84 75–79 70–74 65–69 60–64 55–59 50–54 45–49 40–44 35–39 30–34 25–29 20–24 15–19 10–14 5–9 0–4 0 Age group (years) Source: Statistics Canada (2006). 7 Statistics Canada (2006) makes projections for the entire Canadian population out to 2031, with special data requests available out to 2056. Projections presented here are from the medium growth, medium immigration scenario (scenario 3). 8 16 This also enables consistency with the other vision health projections (Buhrmann, forthcoming). The cost of vision loss in Canada TABLE 2–1: CANADIAN POPULATION PROJECTIONS, MALES (‘000), 2006-2031, SELECTED YEARS Age group 0–4 5–9 10–14 15–19 20–24 25–29 30–34 35–39 40–44 45–49 50–54 55–59 60–64 65–69 70–74 75–79 80–84 85–89 90–94 95–99 100+ Total 2006 2007 2008 2009 2010 2011 2016 2021 2026 2031 868 943 1,068 1,109 1,153 1,125 1,122 1,183 1,357 1,335 1,170 1,029 778 591 490 387 249 115 38 7 1 16,116 872 927 1,054 1,121 1,154 1,138 1,128 1,181 1,322 1,353 1,206 1,038 833 613 490 396 255 123 39 8 1 16,251 875 917 1,037 1,130 1,152 1,152 1,139 1,179 1,279 1,372 1,241 1,054 879 641 495 402 263 131 40 8 1 16,386 876 914 1,020 1,131 1,153 1,165 1,154 1,175 1,241 1,386 1,268 1,081 919 670 504 405 270 138 41 8 1 16,520 879 911 1,002 1,123 1,161 1,173 1,169 1,173 1,217 1,384 1,294 1,114 958 699 515 407 278 143 44 9 1 16,654 884 911 982 1,113 1,171 1,178 1,183 1,172 1,210 1,362 1,321 1,144 991 732 531 409 286 148 48 9 1 16,787 914 928 952 1,029 1,176 1,199 1,238 1,236 1,202 1,220 1,350 1,295 1,107 936 662 449 307 175 64 12 1 17,451 931 960 971 1,001 1,095 1,206 1,263 1,294 1,268 1,216 1,215 1,327 1,256 1,050 852 567 344 192 77 17 2 18,102 929 979 1,004 1,022 1,069 1,129 1,275 1,322 1,329 1,284 1,214 1,198 1,291 1,197 964 736 440 220 87 21 2 18,711 913 980 1,026 1,057 1,092 1,105 1,203 1,338 1,360 1,346 1,282 1,199 1,171 1,235 1,105 841 579 288 103 24 3 19,249 Source: Statistics Canada (2006). 17 The cost of vision loss in Canada TABLE 2–2: CANADIAN POPULATION PROJECTIONS, FEMALES (‘000), 2006-2031, SELECTED YEARS Age group 0–4 5–9 10–14 15–19 20–24 25–29 30–34 35–39 40–44 45–49 50–54 55–59 60–64 65–69 70–74 75–79 80–84 85–89 90–94 95–99 100+ Total 2006 2007 2008 2009 2010 2011 2016 2021 2026 2031 829 900 1,017 1,056 1,100 1,101 1,101 1,168 1,342 1,337 1,194 1,054 806 637 554 491 389 228 99 26 4 16,431 832 885 1,001 1,067 1,103 1,115 1,110 1,165 1,309 1,351 1,229 1,067 863 660 555 495 392 241 102 27 4 16,571 834 876 986 1,075 1,102 1,129 1,121 1,162 1,268 1,366 1,260 1,087 912 689 560 497 395 253 104 29 4 16,709 834 873 970 1,075 1,105 1,141 1,138 1,157 1,232 1,376 1,284 1,117 956 718 571 497 397 263 108 30 4 16,848 835 871 954 1,067 1,115 1,148 1,154 1,156 1,207 1,373 1,306 1,152 1,000 748 583 497 402 269 114 32 4 16,986 841 870 934 1,058 1,124 1,152 1,172 1,155 1,199 1,350 1,330 1,183 1,037 782 600 498 406 274 121 33 5 17,123 868 883 907 978 1,128 1,178 1,225 1,227 1,188 1,211 1,345 1,320 1,165 1,007 739 544 417 291 148 42 6 17,815 885 912 921 952 1,051 1,186 1,255 1,283 1,263 1,203 1,211 1,336 1,302 1,134 955 674 460 303 160 52 8 18,507 883 931 953 968 1,028 1,113 1,268 1,317 1,321 1,278 1,204 1,207 1,321 1,270 1,080 875 576 341 170 58 10 19,172 868 931 973 1,001 1,046 1,094 1,200 1,333 1,357 1,338 1,281 1,202 1,197 1,292 1,214 996 753 432 196 63 11 19,780 Source: Statistics Canada (2006). 18 The cost of vision loss in Canada ETHNICITY 2.1.2 Canada is a racially diverse country. While ‘white’ Europeans make up the great majority of the population (82%), the 2001 Census data showed that Aboriginals (North American Indians, Metis and Inuit) comprised 5% while ‘Visible Minorities’ comprised 13% (East Asians – mainly Chinese), South Asians – mainly Indians, and blacks and other migrant groups9 (Table 2–3). TABLE 2–3: ETHNIC COMPOSITION OF CANADIAN POPULATION (% TOTAL), 2001 Ethnicity % of population Aboriginal Chinese and other East Asian South Asian Black Other White 4.6% 4.1% 3.1% 2.2% 4.1% 81.7% Source: Statistics Canada, topic-based tabulations 95F0363XCB2001004 and 97F0011XCB2001003. Note: Shares may not sum to 100% due to rounding. While at present whites outnumber Aboriginal and Visible Minorities (AVM) by four to one, by the end of the projection period (2032) whites only outnumber AVM by two to one (Figure 2-3)10. 9 For consistency with Statistics Canada data, the term ‘Aboriginal’ is used in this report and ‘North American Indians’ is used rather than ‘First Nations’. For the same reason, ‘black’ is used instead of Caribbean Canadian or African Canadian, and ‘white’ is used instead of European or Caucasian. 10 Statistics Canada makes projections for the population as a whole to 2031, and by race to 2017. Access Economics has extended these trends to 2032, as that represents 25 years after the base year (2007) 19 The cost of vision loss in Canada FIGURE 2-3: WHITE AND AVM POPULATIONS, 2006-2032 (% TOTAL) 90 White Aboriginals and Visible Minorities Percentage of Canadian population 80 70 60 50 40 30 20 10 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 2022 2023 2024 2025 2026 2027 2028 2029 2030 2031 2032 0 Source: Statistics Canada (2005a, 2005b, 2006). Statistics Canada (2005a and 2005b) makes projections for Aboriginal and, separately, Visible Minorities populations to 2017. However, both populations’ shares of the Canadian total have been growing in a fairly linear manner – due to high migration (Visible Minorities) and high birth rates (Aboriginal peoples). Out to 2017, official projections maintain these trends (Figure 2-4). Access Economics has extended the same trends from 2018 through to 2032. 20 The cost of vision loss in Canada FIGURE 2-4: ABORIGINALS AND VISIBLE MINORITIES, 1981-2017, SELECTED YEARS (% POPULATION) 25% Visible Minorities (%) Aboriginal Peoples Trend Trend Share of population, by race 20% 15% 10% 5% 0% 1981 1986 1991 1996 2001 2006 2011 2017 In Canada, demographic aging is less of an issue for non-white populations. Aboriginals in particular have a young age profile (over 60% are under 30 years old), although the East Asian population is fairly evenly spread across all age groups (Figure 2-5 and Figure 2-6). Statistics Canada (2005b) publishes an age-gender profile for Aboriginal peoples at the beginning, middle and end (2017) of its projections. In the absence of further data, Access Economics has assumed that the 2017 profile is maintained through to 2032. This errs on the side of conservatism, as the Aboriginal population might age between 2017 and 2032, which would increase the prevalence of VL. Statistics Canada (2005a) does not publish an age-gender profile for its Visible Minorities projections. However, given most of the growth in this population occurs through immigration, it could reasonably be expected to maintain a similar age-gender profile to that which it has at present. The age-gender profile (as well as total numbers) for whites was estimated as a residual after subtracting Aboriginal and Visible Minorities (AVM) projections from Statistics Canada (2006) total population projections. 21 The cost of vision loss in Canada FIGURE 2-5: AGE DISTRIBUTION OF NON-WHITE MALES (% POPULATION), 2001 8% East Asian South Asian Black Other Visible Minority Aboriginal Percent of population 7% 6% 5% 4% 3% 2% 1% 65 + 55-64 45-54 35-44 25-34 15-24 < 15 0% Age group (years) Source: Statistics Canada, topic-based tabulations 95F0363XCB2001004 and 97F0011XCB2001003. FIGURE 2-6: AGE DISTRIBUTION OF NON-WHITE FEMALES (% POPULATION), 2001 8% East Asian South Asian Black Other Visible Minority Aboriginal Percent of population 7% 6% 5% 4% 3% 2% 1% Age group (years) Source: Statistics Canada, topic-based tabulations 95F0363XCB2001004 and 97F0011XCB2001003. 22 65 + 55-64 45-54 35-44 25-34 15-24 <15 0% The cost of vision loss in Canada It is noteworthy that there is a strong concordance between the ethnic compositions of Canada and Australia (Figure 2-7). Australia is also similar to Canada in culture and standard of living11, and has similar principles and values underlying its health system. FIGURE 2-7: ETHNIC COMPOSITION OF CANADIAN POPULATION COMPARED TO AUSTRALIA’S 100 90 Canada Percent of Population 80 Australia 70 60 50 40 30 20 10 0 European Asian Aboriginal Black / Islander Other / Mixed Note: ‘Black / Islander’ for Canada refers to blacks (72% of whom have Caribbean island heritage) and to Pacific islanders for Australia. Australian data are 2006, Canadian data are 2001. Source: Statistics Canada (2004b) and Statistics Canada Online Topic Based Tabulations, www.statcan.ca (Cat No 97F0010XCB2001004) and, Australian Bureau of Statistics, Australia Year Book 2007 (Cat No 1301.0). 2.2 DATA SOURCES FOR PREVALENCE OF VISION LOSS A variety of data sources were reviewed to estimate prevalence of VL stratified by age, gender, ethnicity, severity (mild and moderate VL and blindness) and cause (AMD, cataract, DR, glaucoma, RE and ‘other’). Since this level of granularity is not available from any single Canadian epidemiological data source, various data sources were combined in order to ensure that Canadian aggregates were used wherever possible, with credible alternative sources used where there were found to be data gaps. Three types of data sources were used. Population-based eye studies. These are the gold standard, where the degree, type and cause of VL are assessed by experts over a large sample of people. However, because such 11 In 2006, according to World Bank statistics Australia’s per capita income was $US 36,000, where Canada’s was $US 36,200 (see http://web.worldbank.org/WBSITE/EXTERNAL/DATASTATISTICS). 23 The cost of vision loss in Canada studies require large amounts of time, money and equipment, they are very rare, and none have been conducted in Canada, although data from the EDPRG eye studies (Appendix A) were utilised where appropriate. Canadian surveys. These large scale collections assemble data from, typically, tens of thousands of respondents, across all ages, genders, ethnicities and geographic areas. The down side is that they are self-diagnosed and self-reported, and thus may suffer a substantial degree of error. Another issue is that publicly available data are usually highly aggregated. Relevant studies in Canada include the Canadian Community Health Survey (CCHS), the National Population Health Survey (NPHS) – a longitudinal study, and the Participation and Activity Limitation Survey (PALS)12. Canadian journal articles and research studies. These often provide a great deal of detail, but only in relation to a small subject area – eg, myopia among children of Chinese immigrants, or use of visual support services by the poor in a particular city, for example. Extensive literature searching has only uncovered a handful of such studies conducted in Canada. Examples include: Cheng et al (2007) on the prevalence of myopia in Chinese-Canadian children; 2.2.1 Hanley et al (2005) on complications of diabetes (including DR) among Aboriginal Canadians; Meddings et al (1998) on the relationship between the development of cataract at a young age and socioeconomic status in British Columbia; Chang et al (1999) on AMD in Chinese-Canadians; and Iskedjian et al (2003) on the costs of treating patients with glaucoma in Canada. POPULATION-BASED EYE STUDIES Population-based eye studies in the US, Australia and the Netherlands show that the prevalence of VL and its underlying eye diseases do not vary greatly between white populations in these countries. Accordingly, data from these studies form the basis of estimates for the white Canadian population. However, these population studies also show significant differences in VL prevalence between given racial groups (eg, East Asian and black) living in wealthy countries (such as Canada) and those living in poorer countries (eg, China, Barbados). Accordingly, wherever possible, data for non-white groups are sourced from Canadian surveys and journal articles (see the following sections). 2.2.2 CANADIAN SELF-REPORTED SURVEY DATA While data from national health surveys are self diagnosed and self reported, they may still be a reasonably good indicator of overall VL, and some major eye diseases. People generally know they have vision problems. The Canadian Ophthalmological Society’s (2006) eye examination guidelines note that less than 1% of the population are unaware of having decreased vision. The exception is glaucoma, where only half of those with the condition are aware of it. Surveys may be a reasonably accurate diagnostic tool. Djafair et al (2003) conducted an interesting evaluation of survey questionnaires as a diagnostic tool. Administering typical survey questions to over 500 patients in a Canadian hospital (whose VL was also able to be 12 Neither the PALS or the CCHS are published in hard copy, but selected data can be tabulated from these surveys at the Statistics Canada website (www.statcan.ca) 24 The cost of vision loss in Canada clinically assessed) resulted in a sensitivity of 82.6% and a specificity of 88.9% for best corrected VL. Conversely, while rates between races are reasonably similar within the CCHS and within the EDPRG data (Congdon et al, 2004a), they do tend to be quite different to each other. (As noted above, the approach adopted herein is to use EDPRG data for Canadian whites, and Statistics Canada data for the AVM population.) The only disease for which AVM prevalence is similar to US whites is glaucoma, which is the disease least likely to be self-diagnosed as most people don’t know they have it. Cataract rates in US whites are some three times higher than in Canadian AVM. Refractive error rates for US whites are around ten times or more higher than Canadian AVM rates – when both are assessed on a best-corrected basis. Moreover the age patterns (for both races) are reversed in CCHS data (increasing with age, where EDPRG data shows decreases with age). As eye health questions are optional for CCHS participants, the data also has a number of gaps due to responses being too small to be statistically valid &/or not contravene privacy regulations. 2.2.2.1 PARTICIPATION AND ACTIVITY LIMITATION SURVEY (PALS, 2001) The PALS asks respondents the following questions. With your glasses or contact lenses, do you have any difficulty seeing ordinary newsprint? Have you been diagnosed by an eye specialist as being legally blind? Besides glasses or contact lenses, do you use any other aids or specialized equipment for persons who are blind or visually impaired eg, magnifiers or Braille reading materials? Figure 2-8 shows the prevalence of seeing disabilities according to this source’s definition, differing somewhat from Statistics Canada (2004a) (recall Figure 1-1). FIGURE 2-8: PREVALENCE OF SEEING DISABILITIES BY AGE AND GENDER (2001) 16% 14% 14.9% Male Female 11.5% Prevalence (%) 12% 10% 8% 6.0% 6% 4% 3.3% 3.4% 2.5% 2% 0.12% 0.13% 0.44% 0.38%0.4% 0.42% 0.24% 0.4% 0.7% 0.9% 0% 0-4 5-9 10-14 15-24 25-44 45-64 65-74 75+ Age group (years) Source: Statistics Canada Online PALS (2001) www.statcan.ca. 25 The cost of vision loss in Canada 2.2.2.2 CANADIAN COMMUNITY HEALTH SURVEY (2005) AND NATIONAL POPULATION HEALTH SURVEY (NPHS) A major limitation for our purposes is that PALS does not provide any information about ethnicity. The CCHS in contrast collects detailed data about ethno-cultural identities and background. Unfortunately, in its publicly available form, the CCHS amalgamates this into only two categories ‘White’ and ‘Other’. The CCHS classified respondents as (under corrected) hyperopic if they could not see well enough to read ordinary newsprint (with glasses); and (under corrected) myopic if they could not recognise a friend across the street (with glasses). The CCHS also asked respondents if they could see at all (ie, blindness), but this was amalgamated in the category ‘myopic and hyperopic and/or blind’. Figure 2-9 shows that in Canada, non-whites have a higher degree than whites of uncorrected VL in younger years, but generally lower rates in older age. This pattern is also apparent for VL from best corrected myopia (Figure 2-10) and for Canadians unable to see clearly at any distance or at all (Figure 2-12). There is a generally higher prevalence of VL from under corrected hyperopia among non-whites (Figure 2-11). FIGURE 2-9: UNCORRECTED VL, BY ETHNICITY, AGE AND GENDER (% POPULATION) 100% 90% 80% Prevalence (%) 70% 60% 50% White Female White Male Non-white Female Non-white Male 40% 30% 20% 10% Years of age Source: Statistics Canada CCHS public use microdata files. 26 80 + 75-79 70-74 65-69 60-64 55-59 50-54 45-49 40-44 35-39 30-34 25-29 20-24 18-19 15-17 12-14 0% The cost of vision loss in Canada FIGURE 2-10: UNDER CORRECTED VL FROM MYOPIA, BY ETHNICITY, AGE AND GENDER (% POPULATION) 8% 7% Prevalence (%) 6% White Female White Male Non-white Female Non-white Male 5% 4% 3% 2% 1% 80 + 75-79 70-74 65-69 60-64 55-59 50-54 45-49 40-44 35-39 30-34 25-29 20-24 18-19 15-17 12-14 0% Years of age Source: Statistics Canada CCHS public use microdata files. Note: Data for non-white males over 65 not supplied. FIGURE 2-11: UNDER CORRECTED VL FROM HYPEROPIA, BY ETHNICITY, AGE AND GENDER (% POPULATION) 6% White Female White Male Non-white Female Non-white Male 5% 3% 2% 1% ALL AGES 80 + 75-79 70-74 65-69 60-64 55-59 50-54 45-49 40-44 35-39 30-34 25-29 20-24 18-19 15-17 0% 12-14 Prevalence (%) 4% Years of age Source: Statistics Canada CCHS public use microdata files. 27 The cost of vision loss in Canada FIGURE 2-12: CANADIANS UNABLE TO SEE CLEARLY AT ANY DISTANCE OR AT ALL, BY ETHNICITY, AGE AND GENDER (% POPULATION) 8% 7% White Female White Male Non-white Female Non-white Male Prevalence (%) 6% 5% 4% 3% 2% 1% 80 + 75-79 70-74 65-69 60-64 55-59 50-54 45-49 40-44 35-39 30-34 25-29 20-24 18-19 15-17 12-14 0% Years of age Source: Statistics Canada CCHS public use microdata files. While elderly male non-whites continue to fit the pattern by having lower cataract prevalence13 than their white contemporaries, there is a divergence for older non-white women, who have the highest cataract prevalence (Figure 2-13). 13 The CCHS only reports cataract prevalence, not VL from cataract. 28 The cost of vision loss in Canada FIGURE 2-13: CATARACT PREVALENCE, BY ETHNICITY, AGE AND GENDER (% POPULATION) 45% 40% 35% White Female White Male Non-white Female Non-white Male Prevalence (%) 30% 25% 20% 15% 10% 5% 80 + 75-79 70-74 65-69 60-64 55-59 50-54 45-49 40-44 35-39 30-34 25-29 20-24 18-19 0% Years of age Source: Statistics Canada CCHS public use microdata files. Over most age ranges, it is non-white males who have the highest rates of glaucoma14 (Figure 2-14). Another important fact to note with glaucoma is that its prevalence appears to be increasing in Canada. Data from various CCHSs and NPHSs compiled by Peruccio et al (2007) show that the prevalence of glaucoma in Canadians over the age of 20 years increased by 64% between 1994 and 2003. Moreover, this is not just due to population aging, as the same trend can be seen within each age group – and in fact the increase is highest in those under 50 years. Some of this increase can be ascribed to improved diagnosis over this period. A similar trend is evident in diabetes, and thus presumably DR (see discussion around Table 2–4). 14 The CCHS only reports prevalence of glaucoma, not of VL from glaucoma 29 The cost of vision loss in Canada FIGURE 2-14: GLAUCOMA, BY ETHNICITY, AGE AND GENDER (% POPULATION) 14% 12% Prevalence (%) 10% White Female White Male Non-white Female Non-white Male 8% 6% 4% 2% 80 + 75-79 70-74 65-69 60-64 55-59 50-54 45-49 40-44 35-39 30-34 25-29 20-24 18-19 0% Years of age Source: Statistics Canada CCHS public use microdata files. Diabetic Retinopathy causes around 600 new cases of blindness in Canada each year15. Despite acknowledging that DR is ‘the leading cause of adult blindness in Canada’16 Statistics Canada does not collect any information on this disease. (The CCHS asks people with diabetes if they have had an eye examination where their pupils were dilated but does not provide the results of these tests.) However, it is possible to derive the prevalence of VL from DR from the CCHS in conjunction with another Statistics Canada publication: Wilkins and Park (1996) calculated from the 1994-95 NPHS that people with diabetes were almost twice as likely as those without (odds ratio of 1.72) to have a vision limitation. Most of this is likely to refer to DR, although Canadians with diabetes also have higher rates of cataract and glaucoma than those without (James et al, 1997). Thus an upper limit for prevalence of VL from DR could be calculated by taking each age-gender cohort in the diabetic population (from Table 2–4) and assigning it 1.72 times the VL prevalence experienced by that cohort in the general population. (This is discussed in more detail in section 2.3.5) 15 Public Health Agency of Canada, National Diabetes Fact Sheet 2007, http://www.phac-aspc.gc.ca/ccdpccpcmc/diabetes-diabete/english/pubs/ndfs-fnrd07-eng.html 16 http://www.statcan.ca/english/research/82-619-MIE/2005002/sequelae.htm (accessed 3 Feb 2008) 30 The cost of vision loss in Canada TABLE 2–4: PREVALENCE OF DIABETES, BY AGE AND GENDER, 2005 (%) Age Male Female All 12-14 15-19 20-24 25-34 35-44 45-54 55-64 65-74 75+ 0.3 0.9 0.9 2.1 5.0 11.8 17.3 16.8 0.3 0.7 1.2 1.9 4.0 8.5 12.3 13.1 0.3 0.3 0.8 1.1 2.0 4.5 10.1 14.6 14.6 Total 5.3 4.4 4.9 Source: Statistics Canada http://www40.statcan.ca/l01/cst01/health53b.htm One important fact to note with diabetes is that it is growing faster than population growth. Moreover, this growth is not just due to population aging either, as the prevalence of diabetes has increased significantly within every age-gender cohort (by an average of over 50% in the decade to 2005, potentially due to increasing rates of obesity and other risk factors). Again, as with glaucoma, the highest increases in prevalence are in the younger ages. This could have significant implications for the prevalence of blindness in Canada over the next 25 years. However, in the interests of conservatism, age-gender prevalence rates were modelled to remain constant in the future. A summary of eye disease prevalence in AVM groups from the 2005 CCHS is contained in Table 2– 5. As noted above, for the white Canadian population, studies in the EDRPG dataset are used. The CCHS does not report the prevalence of either AMD or DR. DR, however, can be estimated indirectly (and is done so in Section 2.3.5, covering VL caused by DR in AVM groups). The prevalence of AMD in Canadian AVMs is assumed to be the same as the average prevalence in non-white Americans (from Congdon et al, 2004a). 31 The cost of vision loss in Canada TABLE 2–5: CCHS PREVALENCE OF EYE DISEASES IN AVM Males Cataract Glaucoma Hyperopia Myopia AMD 0.0% 0.4% 0.0% 0.2% 0.3% 0.1% 1.9% 2.0% 4.4% 11.7% 13.2% 22.9% 16.0% 21.0% 20.99% 20.99% 0.00% 0.05% 0.00% 0.15% 0.82% 0.56% 0.64% 1.18% 4.45% 1.85% 6.26% 9.53% 5.70% 5.99% 5.99% 5.99% 0.47% 1.31% 0.00% 0.00% 0.00% 0.83% 0.40% 1.46% 2.52% 1.48% 2.24% 2.53% 2.82% 2.45% 2.45% 2.45% 0.00% 0.00% 0.80% 0.00% 0.00% 0.32% 0.00% 0.10% 0.92% 0.62% 3.40% 2.16% 2.26% 2.64% 2.64% 2.64% 0.24% 0.39% 0.64% 1.06% 1.75% 2.88% 4.69% 7.55% 7.55% 15-19 20-24 25-29 0.00% 0.05% 0.09% 0.18% 0.00% 0.00% 0.00% 0.18% 2.19% 0.00% 0.00% 0.00% 30-34 0.43% 0.25% 1.42% 0.98% 35-39 40-44 45-49 50-54 55-59 60-64 65-69 70-74 75-79 80-84 85-89 90+ 0.28% 0.56% 0.19% 1.41% 3.46% 10.05% 21.14% 34.68% 36.80% 41.99% 41.99% 41.99% 0.18% 0.50% 0.21% 0.99% 0.65% 2.34% 2.08% 3.07% 11.50% 2.95% 2.95% 2.95% 1.53% 1.63% 1.25% 3.20% 5.15% 3.02% 0.88% 0.31% 3.20% 3.19% 3.19% 3.19% 0.00% 0.00% 0.39% 0.00% 1.00% 0.87% 0.95% 3.17% 3.24% 2.55% 2.55% 2.55% 15-19 20-24 25-29 30-34 35-39 40-44 45-49 50-54 55-59 60-64 65-69 70-74 75-79 80-84 85-89 90+ Females 0.50% 0.70% 0.97% 1.34% 1.85% 2.57% 3.59% 5.02% 5.02% Note: Figures in italics contain no data in original, and are interpolated from relative changes between cohorts in the same ethnicity or gender. Source: Source: Statistics Canada CCHS public use microdata files, Congdon et al (2004a). 2.2.3 DATA FROM CANADIAN JOURNAL ARTICLES AND RESEARCH STUDIES 2.2.3.1 CANADIAN POPULATION STUDIES Maberley et al (2006) conducted an analysis of all ophthalmological records (around 2,500, of which 962 were suitable) in Prince George, a medium-sized Canadian city, over a five year period. They concluded that ‘The overall prevalence of low vision and blindness in Canada are in keeping with 32 The cost of vision loss in Canada data from large population-based studies from other developed nations’. As Figure 2-15 shows, cataract, visual pathway disorders17 and AMD were the leading causes of VL in this study. FIGURE 2-15: CAUSES OF VL IN PRINCE GEORGE, CANADA Other (iris, trauma, lid) 5% Glaucoma 3% DR 7% Cataract 29% Refractive 8% Cornea / conjunctiva 11% AMD 13% Visual pathway 12% Other retinal causes 12% Source: Maberley et al (2006). CNIB has a database of its clients that can also be used to derive an estimate of the causes of blindness in Canada (Table 2–6), assuming that registering with CNIB is equally likely for all causes of blindness. The fact that the elderly blind may have difficulty registering may represent a source of bias, however. TABLE 2–6: CAUSES OF BLINDNESS IN CNIB CLIENTS (2007) Cause Persons (‘000) AMD DR Glaucoma Other 50.2 7.5 7.6 49.2 Total 114.5 Source: CNIB 2.2.3.2 CHINESE CANADIANS Chang et al (1999) reports in a study of 20,000 patients presenting for fluorescein angiography that the rate of AMD in Chinese Canadians (30.4%) was over twice as high as in white Canadians 17 Visual pathway disorders (ICD10 H446-H48) are conditions which impede the visual pathway. Occasionally acute vision loss is caused by homonymous hemianopia and, more rarely, cortical blindness. 33 The cost of vision loss in Canada (14.6%). From this, it may be plausible to assume that AMD in Chinese-Canadians is twice as high as the overall population estimate provided by Maberley et al (2006). Cheng et al (2007) report that Chinese Canadian children aged six years have a prevalence rate of myopia of 22.4%, which is several times the prevalence reported by Robinson (1999) for Canadian six year olds in general of 6.4%. Cheng et al (2007) also report that the prevalence of myopia among Chinese children in Canada is broadly similar to earlier findings from Chinese children in China (Hong Kong) – Figure 2-16. The assumption is made that Chinese-Canadian teenagers have the same rates of myopia as do their counterparts in China in Figure 2-16. However, this appears to decline in later years; Wong (2006) records that Chinese in China over the age of 40 and 60 years have myopia prevalence of 22.9% and 19.4% respectively. FIGURE 2-16: MYOPIA IN CHINESE CHILDREN IN CANADA AND HONG KONG 100 90 Prevalence of myopia (%) 80 70 60 50 40 30 Canada 2003 Hong Kong 1996 20 Hong Kong 2000 10 Hong Kong 2001 0 5 6 7 8 9 10 11 12 13 14 15 Age (years) Source: Cheng et al (2007). If nature dominates nurture for the Canadian Chinese population, as well as having twice the rate of AMD, it is also possible that Chinese Canadians may have twice the rate of DR. The 2001 PALS found that 17.4% of Canadians who have diabetes report a seeing disability. Wong et al (2006) found that 35% of the Chinese population in Taiwan with diabetes have a seeing disability. The Institute for Clinical Evaluative Sciences - ICES (Glazier et al, 2007) note that in the US, African and Hispanic populations have twice the rate of diabetes as do whites; diabetes among Asian Americans is higher than in whites and rising faster than in other ethnic groups; and that in the United Kingdom (UK), South Asians have at least three times the rate of diabetes as the white population. 2.2.3.3 ABORIGINALS Data availability for VL in North American Indians, Metis and Inuit is also scarce. Hanley et al (2005) found 23.3% of North American Indian diabetics in remote communities had DR, with similar figures 34 The cost of vision loss in Canada also being reported by Maberley et al (2002). This is around a third higher than for the general population (albeit lower than the Chinese figures). ICES (Glazier et al, 2007) note that the prevalence of diabetes in Aboriginal communities in Ontario (13%) was three times higher than for the non-indigenous population. Van Rens et al (1988) reported remarkably high levels of POAG in Eskimo women in Alaska (Table 2–7). Similarly, Adams and Adams (1974) reported that the prevalence of POAG in Canadian Inuit women was up to 40 times that in non-Inuit women. TABLE 2–7: PREVALENCE OF POAG AMONG THE ESKIMO (%) Age (years) <49 50-59 60-69 70+ Males 3.1 2.6 3.7 0.5 Females 3.6 11.8 11.8 1.2 Source: Van Rens et al (1988). Young et al (2000) state that Canada’s North American Indians have a ‘high prevalence of serious and untreated diabetic retinopathy’.18 Health Canada (2002b) reports that 25% of Mohawks who have had diabetes for ten years also have DR. TABLE 2–8: PREVALENCE OF DIABETES AMONG CANADIAN ABORIGINAL PEOPLES (1991) 9 8 Prevalence (%) 7 6 5 4 3 2 1 0 Total Aboriginal 18 On-Reserve Off-Reserve Total North North North American American American Indians Indians Indians Metis Inuit They cite Ross and Flick (1991) as their source, but this article does not appear to be electronically available. 35 The cost of vision loss in Canada Source: Health Canada (2002b). 2.2.3.4 BLINDNESS Buhrmann et al (forthcoming) estimate the prevalence of blindness by cause in Canada out to 2031, by applying the breakdown from Congdon et al (2004a) to Statistics Canada’s (total) population projections for selected years. TABLE 2–9: PREVALENCE OF BLINDNESS BY CAUSE, 2006 TO 2031 (% POPULATION) Cause AMD DR Glaucoma 2006 2011 2016 2021 2026 2031 0.4 0.0 0.1 0.4 0.0 0.1 0.5 0.0 0.1 0.5 0.1 0.1 0.5 0.1 0.1 0.6 0.1 0.1 Other 0.2 0.2 0.2 0.2 0.2 0.2 Total 0.7 0.7 0.7 0.8 0.9 1.0 Source: Buhrmann et al (forthcoming). 2.3 PREVALENCE RATES FOR VL 2.3.1 WHITE POPULATION VL As noted above, there have not yet been any major population eye health studies conducted in Canada. Thus, for Canadian whites, the choice falls to using self-diagnosed and self-reported data from the CCHS, or using data from American or Australian eye health studies. Australian data (Centre for Eye Research Australia, 2005)19 is preferred for two reasons. First, Australian VL data for each disease is available by age cohort, which is essential for working with population projections. Second – and potentially reflecting similar ethnic mix and health systems – the Australian proportion of total VL caused by each of the major diseases is significantly closer to Canada’s than the US data (Table 2–10). As the table shows, the proportion of VL caused by cataract in the US is more than three times higher than in Canada, whereas the ratio between Canada and Australia is around 1.30 to 1.00 At the other end of the scale, the proportion of VL due to RE and other is more than five times smaller in the US than it is Canada, whereas the ratio between Australia and Canada is around 1.39 to 1.00. TABLE 2–10: CAUSES OF VL, BY DISEASE, IN WHITE POPULATIONS Disease Cataract Glaucoma DR AMD RE/Other US Canada Australia 59.2% 3.3% 4.9% 22.9% 9.7% 18.6% 7.0% 7.0% 16.3% 51.3% 14.3% 2.9% 1.6% 10.1% 71.2% Sources: US (Congdon et al, 2004a), Canada (Maberley et al, 2006), Australia (CERA, 2005) 19 These data have been published in a number of journal articles, including Taylor, Pezzullo and Keeffe (2006) 36 The cost of vision loss in Canada Australian VL Access Economics (2007) used data from the MVIP to determine the prevalence of VL caused by AMD (Table 2–11). Severity was measured according to the better seeing eye (noting that with AMD it can become the worse one over time). For Canada, the distribution between mild, moderate and severe VL from AMD and by age are based on these data, as it was considered likely that AMD incidence and progression follows a similar pathway in Canada. TABLE 2–11: PREVALENCE OF VL DUE TO AMD, BY SEVERITY (% OF AGE GROUP) Age Mild 0-69 70-74 75-79 80-84 85-89 90+ 40+ 0.00 0.17 0.00 1.00 2.13 3.15 0.10 Moderate 0.00 0.00 0.87 1.00 4.26 6.29 0.33 Severe 0.00 0.17 0.00 1.00 3.19 4.72 0.13 Source: Access Economics (2007). The Centre for Eye Research Australia (CERA, 2005) estimated the prevalence of VL caused by cataract in Australia, also from the MVIP (Table 2–12). For Canada, as with AMD, the distribution between mild, moderate and severe VL from cataract and by age are based on these data. TABLE 2–12: PREVALENCE RATES FOR VL FROM CATARACTS, BY AGE AND SEVERITY (%) Age 40-49 50-59 60-69 70-79 80-89 90+ Total VL (<20/40) 0.0% 0.0% 0.1% 1.4% 6.6% 15.2% VL by severity Mild (6/12 to 6/18) Moderate (<6/18 to 6/60) Severe (>6/60) Total 60.2% 26.7% 13.0% Source: CERA (2005). Access Economics (2008c, forthcoming) provides estimates of the prevalence of VL caused by DR (Table 2–13), based on combined data from the MVIP and Blue Mountains Eye Study (BMES). For Canada, the distribution between mild, moderate and severe VL from DR and by age are again based on these data. TABLE 2–13: PREVALENCE RATES FOR VISION IMPAIRMENT (<6/12) FROM DR, AND PROPORTION BY STAGE OF VISION LOSS Age 40-49 50-59 60-69 70-79 80-89 90+ Total VL (<20/40) 0.0% 0.0% 0.2% 0.1% 0.5% 0.6% VL by severity Mild (6/12 to 6/18) Moderate (<6/18 to 6/60) Severe (>6/60) Total 30.6% 47.8% 21.6% (a) Prevalence based on combined data from the MVIP and BMES. (b) Stages of vision loss based on MVIP. Source: Access Economics (2008c). Access Economics (2008b) estimated the prevalence of VL caused by POAG, by degrees of severity, from the MVIP and the BMES (Table 2–14). For Canada, the distribution between mild, moderate and severe VL from glaucoma and by age are once again based on these data. 37 The cost of vision loss in Canada TABLE 2–14: PROPORTION OF PEOPLE WITH GLAUCOMA BY AGE AND SEVERITY (%) Age Group 0-59 60-64 65-69 70-74 75-79 80-84 85-89 90+ Mild 0.0 0.2 0.4 0.5 1.2 1.7 2.2 1.1 Moderate Severe 0.0 1.7 2.8 3.7 8.4 11.5 15.1 7.7 0.0 2.9 2.6 3.3 1.8 2.5 4.8 20.6 Source: Based on combined data from the MVIP and BMES. Most people with glaucoma in developed countries are unaware they have the disease (Canadian Ophthalmological Society, 2007). Even among those regularly visiting eye professionals, the probability of diagnosis depends on the severity of the condition. Hence, the more severe forms have the highest (diagnosed) prevalence. Wong et al (2004) examined the presence of undiagnosed glaucoma in people who had visited an eye care provider in the previous year using MVIP data. They found that 81% of possible cases, 72% of probable cases and 59% of definite cases of glaucoma were previously undiagnosed by the eye care provider. CERA (2005) estimated the prevalence of VL caused by RE in Australia from the MVIP (Table 2– 15). For Canada, the relativities between mild, moderate and severe VL from RE and by age are based on these data, as it is likely that RE incidence and progression follows a similar pathway in Canada. TABLE 2–15: PREVALENCE RATES FOR VL FROM RE, BY AGE AND SEVERITY (%) Age 40-49 50-59 60-69 70-79 80-89 90+ Total VL (<20/40) VL by severity Total 0.5% 1.8% 3.9% 7.8% 13.0% 7.9% Mild (6/12 to 6/18) Moderate (<6/18 to 6/60) Severe (>6/60) 83.4% 14.6% 2.0% Source: CERA (2005). In addition to the above breakdowns by severity, CERA (2005) also gives an overall prevalence of VL caused by each major eye disease, which is used as the basis for the prevalence of VL by cause for Canadian whites (Table 2–16). 38 The cost of vision loss in Canada TABLE 2–16: ESTIMATED VL PREVALENCE IN CANADIAN WHITES BY DISEASE AND AGE 40-44 45-49 50-54 55-59 60-64 65-69 70-74 75-79 80-84 85-89 90+ Cataract DR 0.00% 0.08% 0.01% 0.16% 0.73% 2.37% 5.49% 8.71% 15.17% 0.00% 0.09% 0.12% 0.16% 0.16% 0.10% 0.44% 0.78% 0.68% 0.58% Glaucoma AMD RE Other 0.00% 0.16% 0.20% 0.34% 1.52% 1.32% 1.23% 0.00% 0.00% 0.00% 0.00% 0.08% 0.22% 1.70% 2.31% 8.77% 12.97% 0.71% 0.29% 1.05% 2.62% 2.51% 5.38% 6.30% 9.87% 13.13% 12.80% 7.86% 0.18% 0.14% 0.52% 0.17% 0.25% 0.43% 0.64% 0.78% 0.92% 3.75% 2.44% Source CERA (2005). 2.3.2 ABORIGINALS AND VISIBLE MINORITIES (AVM) VL There are severe data problems in estimating the prevalence of VL among Canada’s AVM populations. While the CCHS collects the prevalence of eye diseases, by age, for the AVM population, it does not collect data on the causes of VL. Moreover, the prevalence data are not disaggregated by race, despite known differences between races (Figure 2-17). There have been some international population eye health studies covering the causes of VL in non-whites, but the races (blacks and Hispanics) covered were not representative of Canada’s AVM population (blacks are 2% of the Canadian population, and Hispanic does not rate a category in the Canadian census). Moreover the data is not available by age-cohort which, given how greatly the incidence of VL varies by age, makes it very difficult to map to Canada’s AVM population. FIGURE 2-17: CAUSES OF BLINDNESS BY ETHNICITY (US) Source: Congdon et al (2004a). Access Economics’ approach has been to estimate from international sources the likelihood that a non-white person who has an eye disease will develop VL, and apply that ratio to the CCHS 39 The cost of vision loss in Canada prevalence of that disease in Canada’s AVM population. The next few paragraphs illustrate the concepts involved using illustrative round numbers. Suppose, for example, that 25% of the US non-white population who have cataract will also have VL from that disease. Suppose further, that 10,000 Canadian AVM have cataract. Then - if making the assumption that the share of non-whites with cataract who have VL is similar on both sides of the border - there are an estimated 2,500 (=10,000 * 25%) AVM who suffer VL because of their cataracts. Prevalence rates of cataract by age group among Canadian AVM are known and Congdon et al (2004a) reports that, in America, if a white and a non-white both have cataract, the white is more likely to suffer VL from the disease (for illustrative purposes, suppose twice as likely). Assuming that American, Australian and Canadian whites are similar in this relative risk, then if 80% of 80 year old (Australian) whites with cataract have VL, it follows that half as many (40%) of Canadian non-whites (Canadian) with cataract will have VL. So if the CCHS reports that there are 1,000 80 year old Canadian AVM with cataract, 400 of them (=1,000 * 40%) are estimated to have VL. 2.3.3 CATARACT-INDUCED VL IN AVM Because there are multiple races and multiple diseases, this section works through one disease in detail – cataract – using actual data, and other disease prevalence rates are similarly calculated. Using the NEI disease prevalence (http://www.nei.nih.gov/eyedata/tables.asp) and 2000 US Census data (http://factfinder.census.gov/), an estimated 7.47% of the white population had cataract (Row A, Table 2–17). Access Economics (2006) shows that 2.79% of white Americans had VL (Row B). Congdon et al (2004a) show that 59.2% of this total VL was caused by cataract (Row C). Thus, the prevalence of cataract-induced VL was 1.65% (59.2% times 2.79%) of the white population (Row D). Thus, it can be deduced that 22.1% (1.65/7.47) of whites who have cataract will also have VL from those cataracts (Row E). TABLE 2–17: PREVALENCE OF VL IN US WHITES WITH CATARACTS (2000) Factor % A. Prevalence of cataract B. Prevalence of VL C. Proportion of VL caused by cataract D. Prevalence of cataract-induced VL (C*B) E. Percent of cataract population who have VL (D/A) 7.47% 2.79% 59.2% 1.65% 22.1% Sources: Access Economics (2006), Congdon et al (2004a). For blacks, the same data show that 6.42% of the black population had cataract (Row A, Table 2– 18). Access Economics (2006) shows that 2.28% of black Americans had VL (Row B). Congdon et al (2004a) show that 50.9% of this total VL was caused by cataract (Row C). Thus, the prevalence of cataract-induced VL was 1.16% (50.9% times 2.79%) of the black population (Row D) and it can be deduced that 18.1% (1.16/6.42) of blacks who have cataract will also have VL from those cataracts (Row E). 40 The cost of vision loss in Canada TABLE 2–18: PREVALENCE OF VL IN US BLACKS WITH CATARACTS (2000) Factor % A. Prevalence of cataract B. Prevalence of VL C. Proportion of VL caused by cataract D. Prevalence of cataract-induced VL (C*B) E. Percent of cataract population who have VL (D/A) 6.42% 2.28% 50.9% 1.16% 18.1% Sources: Access Economics (2006), Congdon et al (2004a). For Hispanics, the data record that 6.96% of the Hispanic population had cataract (Row A, Table 2– 19). Access Economics (2006) shows that 1.96% of Hispanic Americans had VL (Row B). Congdon et al (2004a) show that 46.7% of this total VL was caused by cataract (Row C). Thus, the prevalence of cataract-induced VL was 0.91% (46.7% times 1.96%) of the Hispanic population (Row D) and it can be deduced that 13.1% (0.91/6.96) of Hispanics who have cataract will also have VL from those cataracts (Row E). TABLE 2–19: PREVALENCE OF VL IN US HISPANICS WITH CATARACTS (2000) Factor % A. Prevalence of cataract B. Prevalence of VL C. Proportion of VL caused by cataract D. Prevalence of cataract-induced VL (C*B) E. Percent of cataract population who have VL (D/A) 6.96% 1.96% 46.7% 0.91% 13.1% Sources: Access Economics (2006), Congdon et al (2004a). Finally, for other races, according to the data, 6.96% of the remaining population of other races had cataract (Row A, Table 2–20). Access Economics (2006) shows that 2.15% of ‘other’ Americans had VL (Row B). Congdon et al (2004a) show that 52.3% of this total VL was caused by cataract (Row C). Thus, the prevalence of cataract-induced VL was 1.12% (52.3% times 2.15%) of the remainder of the population (Row D) and it can be deduced that 16.2% (1.12/6.96) of other races who have cataract will also have VL from those cataracts (Row E). TABLE 2–20: PREVALENCE OF VL IN US ‘OTHER’ WITH CATARACTS (2000) Factor % A. Prevalence of cataract B. Prevalence of VL C. Proportion of VL caused by cataract D. Prevalence of cataract-induced VL (C*B) E. Percent of cataract population who have VL (D/A) 6.96% 2.15% 52.3% 1.12% 16.2% Sources: Access Economics (2006), Congdon et al (2004a). Drawing this together, it is possible to estimate how much less likely the average non-white is to develop VL after contracting cataracts than is the average white (Table 2–21). Weighting the three non-white races (black, Hispanic and ‘other’) by their respective shares of the Canadian AVM population (blacks 12%, Latin Americans20 4%, ‘other’ 84%) yields the result that 16.3% of Canadian 20 As noted above, the Canadian census does not include the category ‘Hispanic’; ‘Latin American’ is used as a proxy. 41 The cost of vision loss in Canada AVM with cataract will have VL from their cataracts (Row E). This in turn indicates that an AVM person with cataract is only 74% as likely to develop VL as is a white person with cataract (Row F). TABLE 2–21: RELATIVE RISK OF DEVELOPING VL FROM CATARACTS, BY RACE Race/Ethnic group A. Whites (Table 2–17) B. Blacks (Table 2–18) C. Hispanic (Table 2–19) D. Other (Table 2–20) E. Non-white weighted average F. Ratio average non-white to white (E/A) Prevalence of VL in those with cataract Share of Canadian AVM population 22.1% 18.1% 13.1% 16.2% 16.3% 12% 4% 84% 0.74 Source: Derived from previous tables. Having derived above that, over the whole population, an AVM person with cataract is around threequarters as likely to have VL as a white person, this is then applied to the fraction of whites with cataracts who have VL (Column C in Table 2–22). The latter, in turn, is derived from the prevalence of cataract-induced VL (from Table 2–16, reproduced as Column A in Table 2–22) and from the prevalence of cataract as a disease in whites (from the Australian Bureau of Statistics, 2006, Column B below). TABLE 2–22: PREVALENCE OF VL IN WHITES WITH CATARACT, BY AGE Age A. Prevalence of cataract B. Prevalence of cataract induced VL 35-39 40-44 45-49 0.2% 0.2% 0.5% 0.0% 0.0% 0.0% C. Fraction of those with cataracts who have VL (B/A) 0.0% 0.0% 0.0% 50-54 55-59 60-64 65-69 70-74 75-79 80-84 85-89 90+ 0.5% 1.5% 1.5% 5.1% 5.1% 13.2% 13.2% 19.9% 19.9% 0.0% 0.1% 0.0% 0.2% 0.7% 2.4% 5.5% 8.7% 15.2% 0.0% 5.5% 0.7% 3.2% 14.2% 17.9% 41.5% 43.8% 76.2% Sources: CERA (2005), Australian Bureau of Statistics (2006). The likelihood that a non-white with cataract will develop VL (Column C in Table 2–23) can then be derived from the fraction of whites with cataracts who have VL (from Table 2–22, reproduced as Column A in Table 2–23) and the relative risk between whites and non-whites (from Table 2–21, reproduced as Column B). 42 The cost of vision loss in Canada TABLE 2–23: PREVALENCE OF VL IN NON- WHITES WITH CATARACT, BY AGE Age A. Fraction of whites with cataracts who have VL B. Relative risk of developing VL from cataract (nonwhite/white) C. Fraction of non-whites with cataracts who have VL (A*B) 35-39 40-44 45-49 0.0% 0.0% 0.0% 0.74 0.74 0.74 0.0% 0.0% 0.0% 50-54 55-59 60-64 65-69 70-74 75-79 80-84 85-89 90+ 0.0% 5.5% 0.7% 3.2% 14.2% 17.9% 41.5% 43.8% 76.2% 0.74 0.74 0.74 0.74 0.74 0.74 0.74 0.74 0.74 0.0% 4.1% 0.5% 2.3% 10.5% 13.2% 30.5% 32.2% 56.1% Source: derived from Tables 2-21 and 2-22. Finally, having derived how likely a non-white with cataract is to develop VL (Table 2–23), it remains to ascertain how many non-whites have cataract. This information is provided by the CCHS (Table 2–5) and reproduced as Column A in Table 2–24. Multiplying the number of AVM with cataract (Column A) by their chance of having VL (Column B) gives the prevalence of VL from cataract in the AVM population by age group. For example, if 22.9% of AVM aged between 70 and 74 have cataract, and 10.5% of these develop VL, then around 2.4% of AVM in this age group will have VL caused by cataract. 43 The cost of vision loss in Canada TABLE 2–24: PREVALENCE OF CATARACT-INDUCED VL IN CANADIAN AVM, BY AGE A Prevalence of cataract in nonwhites B Fraction of nonwhites with cataracts who have VL C Prevalence of cataract-induced VL in non-whites (A*B) Males 35-39 40-44 45-49 50-54 55-59 60-64 65-69 70-74 75-79 80-84 85-89 90+ Females 35-39 40-44 45-49 50-54 55-59 60-64 65-69 70-74 75-79 80-84 85-89 90+ 0.3% 0.1% 0.0% 0.0% 0.0% 0.0% 1.9% 2.0% 4.4% 11.7% 13.2% 22.9% 16.0% 21.0% 21.0% 21.0% 0.0% 0.0% 4.1% 0.5% 2.3% 10.5% 13.2% 30.5% 32.2% 56.1% 0.0% 0.0% 0.2% 0.1% 0.3% 2.4% 2.1% 6.4% 6.8% 11.8% 0.3% 0.6% 0.2% 1.4% 3.5% 10.0% 21.1% 34.7% 36.8% 42.0% 42.0% 42.0% 0.0% 0.0% 0.0% 0.0% 4.1% 0.5% 2.3% 10.5% 13.2% 30.5% 32.2% 56.1% 0.0% 0.0% 0.0% 0.0% 0.1% 0.1% 0.5% 3.6% 4.9% 12.8% 13.5% 23.5% Source: Derived from above tables and data from the CCHS. 2.3.4 VL CAUSED BY AMD, GLAUCOMA AND RE IN AVM The exercise in the previous section can be repeated for VL in AVM caused by the other major eye diseases, except DR, which is dealt with by a different method, using solely Canadian data, in Section 2.3.5. Table 2–25 reports the prevalence of each eye disease in each non-white group from the NEI dataset (weighted by 2000 Census age cohorts, as above). TABLE 2–25: PREVALENCE OF EYE DISEASES BY ETHNICITY, US, 2000 White A. AMD B. Cataract C. Glaucoma D. RE/Other 0.8% 7.5% 0.7% 16.7% Black 0.4% 6.4% 1.6% 8.6% Hispanic 0.4% 7.0% 0.9% 10.7% Other 0.4% 7.0% 1.0% 10.9% Source: US Census 2000 (http://factfinder.census.gov/servlet/STTable?_bm=y&-geo_id=01000US&qr_name=ACS_2006_EST_G00_S0101&-ds_name=ACS_2006_EST_G00_) EDPRG (http://www.nei.nih.gov/eyedata/tables.asp) 44 The cost of vision loss in Canada The prevalence of VL caused by each eye disease is derived from Congdon et al (2004a), which reports both the total prevalence of VL for each race in the US (Row E in Table 2–27) and the percentage of this VL which is caused by each major disease (Table 2–26). The prevalence of VL by disease is then derived as per cataract in the previous section, presented in Table 2–28. TABLE 2–26: CAUSES OF VL BY ETHNICITY21 White A. AMD B. Cataract C. Glaucoma D. RE/Other 22.9% 59.2% 3.3% 9.7% Black Hispanic 3.2% 50.9% 14.3% 17.0% 14.3% 46.7% 7.6% 18.5% Other 13.5% 52.3% 8.4% 15.1% Source: Congdon et al (2004a). TABLE 2–27: PREVALENCE OF VL, BY ETHNICITY AND CAUSE, US, 2000 White A. AMD B. Cataract C. Glaucoma D. RE/Other E. Sum 0.64% 1.65% 0.09% 0.27% 2.79% Black 0.07% 1.16% 0.33% 0.39% 2.28% Hispanic 0.28% 0.91% 0.15% 0.36% 1.96% Other 0.29% 1.12% 0.18% 0.32% 2.15% Source: Access Economics (2006), Table 2–26. TABLE 2–28: PREVALENCE (%) OF VL WITHIN SPECIFIED DISEASES, BY ETHNICITY White A. AMD B. Cataract C. Glaucoma D. RE/Other 95.2 22.1 14.0 1.6 Black 17.4 18.1 20.1 4.5 Hispanic 63.2 13.1 16.7 3.4 Other 69.5 16.2 17.9 3.0 Source: Derived from Table 2–25 and Table 2–27. Extending the above analysis across ethnicities and diseases, Figure 2-18 shows the variance in the probability of VL across diseases and ethnic groups. For example, AMD appears to have a significantly greater likelihood of causing VL in whites than in blacks, while RE is more likely to cause VL in blacks than whites. This may possibly be due to genetic factors or to socioeconomic factors governing access to medical care (and thus detection and treatment). 21 DR is not included as it is calculated separately in Section 2.3.5. Rates are white 5%, black 15%, Hispanic 13%, other 11%. 45 The cost of vision loss in Canada FIGURE 2-18: PROBABILITY OF DEVELOPING VL AFTER CONTRACTING SELECTED DISEASES, BY ETHNICITY Probability of visual impairment after contracting specified disease (%) 100.0 White Black Hispanic Other 90.0 80.0 70.0 60.0 50.0 40.0 30.0 20.0 10.0 0.0 Cataract Glaucoma DR RE/Other AMD Source: Derived from EDPRG (Congdon et al, 2004a) and US Census data. As with the methodology for cataract, the relative risk of VL from a particular disease is compared between whites and each other group and a weighted average is developed using the population weights for each group among the Canadian AVM total (Table 2–29). TABLE 2–29: RELATIVE RISK OF VL BY EYE DISEASE, NON-WHITES TO WHITES Disease A. AMD B. Cataract C. Glaucoma D. RE/Other Relative Risk 1.52 0.74 1.29 1.96 Source: Derived from previous tables and Canadian Census data. To derive an age breakdown for the relative risks for the non-white population, data on prevalence of each disease were used from the Australian Bureau of Statistics (2006) and the Australian Institute of Health and Welfare (2005) (Table 2–30). TABLE 2–30: PREVALENCE OF EYE DISEASES IN WHITES Age 40-44 45-49 50-54 55-59 60-64 65-69 70-74 75-79 80-84 85-89 90+ AMD 0.1% 0.3% 0.3% 0.8% 0.8% 1.1% 1.1% 3.7% 3.7% 6.3% 6.3% Cataract 0.2% 0.5% 0.5% 1.5% 1.5% 5.1% 5.1% 13.2% 13.2% 19.9% 19.9% Glaucoma 0.2% 0.8% 0.8% 1.3% 1.3% 2.4% 2.4% 6.3% 6.3% 7.2% 7.2% RE/Other 43.9% 77.4% 77.4% 70.9% 70.9% 52.8% 52.8% 54.1% 54.1% 51.2% 51.2% Source: Australian Bureau of Statistics (2006), Australian Institute of Health and Welfare (2005). 46 The cost of vision loss in Canada Recall that the prevalence of VL in whites by cause was shown in Table 2–16. Using that prevalence and the prevalence of each disease (Table 2–30) gives the fraction of VL caused by that disease (Table 2–31) for each five-year age cohort in the white population. TABLE 2–31: FRACTION OF WHITES WITH EACH EYE DISEASE WHO HAVE VL, BY AGE AND GENDER (%) Age 40-44 45-49 50-54 55-59 60-64 65-69 70-74 75-79 80-84 85-89 90+ AMD 0.0% 0.0% 0.0% 7.4% 20.2% 45.4% 61.5% 100.0% 100.0% Cataract 0.0% 0.0% 0.0% 5.5% 0.7% 3.2% 14.2% 17.9% 41.5% 43.8% 76.2% Glaucoma 0.0% 0.0% 0.0% 0.0% 0.0% 6.7% 8.2% 5.4% 24.3% 18.3% 17.0% RE/Other 2.0% 0.6% 2.0% 3.9% 3.9% 11.0% 13.1% 19.7% 26.0% 32.3% 20.1% Note: AMD prevalences in 85 years and older capped at 100% Source: Congdon et al (2004a), Access Economics (2007). Combining the fractions in Table 2–31 with the relative risks (non-white to white) from Table 2–29 leads to the prevalence of VL within disease groups in non-whites as per Table 2–32. TABLE 2–32: PREVALENCE OF VL WITHIN DISEASE GROUPS, NON-WHITES Age AMD 40-44 45-49 50-54 55-59 60-64 65-69 70-74 75-79 80-84 85-89 90+ 0.0% 0.0% 0.0% 10.5% 28.6% 64.4% 87.3% 100.0% 100.0% Cataract 0.0% 0.0% 0.0% 4.1% 0.5% 2.3% 10.5% 13.2% 30.5% 32.2% 56.1% Glaucoma 0.0% 0.0% 0.0% 0.0% 0.0% 8.7% 10.6% 7.0% 31.2% 23.5% 21.8% RE/Other 4.0% 1.1% 4.0% 7.7% 7.6% 21.5% 25.7% 38.6% 50.8% 63.3% 39.4% Source: Derived from previous tables. Using this with the prevalence of eye disease in AVM from CCHS data (Table 2–5) results in the prevalence of VL from that disease (Table 2–33). 47 The cost of vision loss in Canada TABLE 2–33: PREVALENCE OF VL IN AVM Males AMD 40-44 45-49 50-54 55-59 60-64 65-69 70-74 75-79 80-84 85-89 90+ Females 40-44 45-49 50-54 55-59 60-64 65-69 70-74 75-79 80-84 85-89 90+ 2.3.5 0.00% 0.00% 0.00% 0.11% 0.50% 1.85% 4.09% 7.55% 7.55% AMD 0.00% 0.00% 0.00% 0.14% 0.53% 1.66% 3.13% 5.02% 5.02% Cataract Glaucoma RE/Other 0.00% 0.00% 0.00% 0.00% 0.05% 0.00% 0.00% 0.18% 0.06% 0.31% 2.40% 0.00% 0.00% 0.00% 0.54% 1.01% 0.06% 0.27% 0.16% 1.22% 1.21% 2.11% 6.41% 6.76% 11.77% 0.40% 1.87% 1.41% 1.31% 1.96% 2.59% 3.22% 2.01% Cataract Glaucoma RE/Other 0.00% 0.00% 0.00% 0.14% 0.05% 0.49% 3.63% 4.85% 12.82% 0.00% 0.00% 0.00% 0.00% 0.00% 0.18% 0.33% 0.80% 0.92% 0.06% 0.02% 0.13% 0.47% 0.30% 0.39% 0.89% 2.48% 2.92% 13.52% 23.54% 0.69% 0.64% 3.63% 2.26% DIABETES AND DR IN THE AVM POPULATION The above methods cannot be fully used for DR in the Canadian AVM population, because the CCHS does not report on the prevalence of DR in AVM. However, there are sufficient Canadian data from other sources to estimate age-gender prevalence of DR using an alternate methodology discussed in this section. Data from various Canadian publications enable an estimate of VL from DR in the AVM population to be calculated directly (rather than having to rely on non-Canadian EDPRG data.) Statistics Canada’s Health Report (Wilkins and Park, 1996) shows that the prevalence of VL among Canadian diabetics is 72% higher than in the general population. However, as Access Economics (2008c) notes, diabetics also have higher rates of cataract, glaucoma and macular edema, with the result that the prevalence of DR in diabetics is roughly equivalent to the combined prevalence of these three other diseases in diabetics. Thus, it was assumed that half of the increased rate of VL (36%) is due to DR (rather than the other three associated eye diseases). Increasing the 2005 CCHS figures for the prevalence of under corrected VL in the AVM population (Table 2–34) by 36% enabled an estimate of the prevalence of DR-induced VL among diabetics in this population (Table 2–35). 48 The cost of vision loss in Canada TABLE 2–34: UNDER CORRECTED VL IN AVM Age Male Female 20-24 25-34 1.3% 0.4% 1.0% 3.9% 35-44 0.6% 1.4% 45-54 55-64 65-74 0.2% 1.7% 1.7% 1.0% 3.1% 2.0% 75+ 3.7% 4.7% Source: Statistics Canada, CCHS public use microdata files. TABLE 2–35: PREVALENCE OF VL FROM DR WITHIN DIABETIC AVM GROUPS Age Male Female 20-24 1.8% 1.4% 25-34 35-44 45-54 55-64 65-74 75+ 0.5% 0.8% 0.3% 2.3% 2.3% 5.0% 5.3% 1.9% 1.3% 4.2% 2.8% 6.4% Source: Derived from Table 2–34. Although the CCHS does not provide an estimate of diabetic prevalence in the AVM population, ICES (Glazier et al, 2007) reports that rates of diabetes among First Nation groups in Ontario are among the highest in the world, and are some three times higher than for the rest of the population. ICES also reports that diabetes in Ontario’s South Asian population is three times the general population. They also note the prevalence of diabetes in black Americans is twice as high as the general population, which might reasonably be assumed to apply also to black Canadians. Finally, ICES reports that the prevalence of diabetes in Toronto neighbourhoods is strongly correlated with the percentage of the population from Visible Minorities. Taken together, Access Economics has conservatively assumed that the rate of diabetes in the AVM population is twice that of the white population. Statistics Canada publishes rates of diabetes for the general population (Table 2–4). Doubling these rates thus yields an estimate of the prevalence of diabetes in the AVM population (Table 2–36). TABLE 2–36: PREVALENCE OF DIABETES IN AVM POPULATION, 2005 (%) Age 12-14 15-19 20-24 25-34 35-44 45-54 55-64 65-74 75+ Total Male Female All 0.0% 0.6% 1.8% 1.8% 4.2% 10.0% 23.6% 34.6% 33.6% 10.6% 0.0% 0.6% 1.4% 2.4% 3.8% 8.0% 17.0% 24.6% 26.2% 8.8% 0.6% 0.6% 1.6% 2.2% 4.0% 9.0% 20.2% 29.2% 29.2% 9.8% Source: As per Table 2–4, and ICES (Glazier et al, 2007). 49 The cost of vision loss in Canada Multiplying the prevalence of diabetes in the AVM population (Table 2–36) by the prevalence of VL in the AVM diabetic population (Table 2–35) provides the prevalence of AVM diabetics who have DR-induced VL (Table 2–37). TABLE 2–37: ESTIMATED PREVALENCE OF DR-INDUCED VL IN AVM 20 to 24 25 to 34 35 to 44 45 to 54 55 to 64 65 to 74 75 and older Male Female 0.03% 0.01% 0.03% 0.03% 0.55% 0.80% 1.69% 0.02% 0.13% 0.07% 0.11% 0.71% 0.68% 1.67% Source: Derived from earlier tables. 2.3.6 SUMMARY OF VL IN AVM POPULATIONS Combining the prevalence of VL from DR (Table 2–37) with the prevalence estimates for the other eye diseases (Table 2–33) enables a completion of the estimates of VL by disease for the whole AVM population (Table 2–38). As noted above, the CCHS does not report VL by disease, only the prevalence of the diseases. However, it does report the total number of AVM who have undercorrected VL (Table 2–34). Self-reported VL for AVM was 0.8% for males and 2.0% for females. The estimates here, derived from ratios of diagnosed VL between races, are 0.5% for AVM males, and 0.7% for AVM females (Table 2–40). 50 The cost of vision loss in Canada TABLE 2–38: PREVALENCE OF VL IN AVM BY AGE, GENDER AND DISEASE Males 40-44 45-49 50-54 55-59 60-64 65-69 70-74 75-79 80-84 85-89 90+ Female 40-44 45-49 50-54 55-59 60-64 65-69 70-74 75-79 80-84 85-89 90+ 2.4 AMD 0.00% 0.00% 0.00% 0.11% 0.50% 1.85% 4.09% 7.55% 7.55% AMD 0.00% 0.00% 0.00% 0.14% 0.53% 1.66% 3.13% 5.02% 5.02% Cataract 0.00% 0.00% 0.00% 0.18% 0.06% 0.31% 2.40% 2.11% 6.41% 6.76% 11.77% Cataract 0.00% 0.00% 0.00% 0.14% 0.05% 0.49% 3.63% 4.85% 12.82% 13.52% 23.54% DR 0.03% 0.03% 0.03% 0.55% 0.55% 0.80% 0.80% 1.69% 1.69% 1.69% 1.69% Glaucoma DR 0.07% 0.11% 0.11% 0.71% 0.71% 0.68% 0.68% 1.67% 1.67% 1.67% 1.67% Glaucoma 0.00% 0.00% 0.00% 0.00% 0.00% 0.54% 1.01% 0.40% 1.87% 1.41% 1.31% 0.00% 0.00% 0.00% 0.00% 0.00% 0.18% 0.33% 0.80% 0.92% 0.69% 0.64% RE/Other 0.05% 0.00% 0.06% 0.27% 0.16% 1.22% 1.21% 1.96% 2.59% 3.22% 2.01% RE/Other 0.06% 0.02% 0.13% 0.47% 0.30% 0.39% 0.89% 2.48% 2.92% 3.63% 2.26% SUMMARY A variety of data sources were used to construct a model of Canadian VL by age, gender, ethnicity, severity and type. There was found to be little difference in the prevalence of visually impairing eye conditions among white populations in US, Australian and European population eye health studies, so these studies (Congdon et al, 2004a and CERA, 2005) were used to estimate the prevalence of VL for white Canadians. For AVM, self-reported data from the CCHS were used to estimate the prevalence of cataract, glaucoma and RE, with supplementation from Canadian academic studies and journal articles for DR and AMD, since these conditions are not covered in the CCHS. DR was estimated from other Canadian sources and AMD was estimated from the average prevalence rates for non-whites in the US. The risk of VL within each disease for AVM was derived from the risk for non-whites in the US. These data show that differences in the rates of VL from ‘disease x’ are related to differences in prevalence of that disease across ethnicities as well as differences in access to treatment and genetic factors that may affect progression of VL. Since the self-reported data do not distinguish between mild and medium levels of VL, the severity distribution is assumed to be the same for AVM as for whites (by disease). In total, there were an estimated 816,951 Canadians with VL in 2007 (Table 2–39). Of this total, 780,534 (95.5%) were white and 36,417 (4.5%) were AVM. RE / Other is the main source of VL for the white population (68% of the total), and cataract is the main cause of VL in AVM (36% of the total). 51 The cost of vision loss in Canada For whites the second largest source of VL is cataract (15.5%) and, for the AVM population, DR is the second largest source (24.5% of the total).22 AVM have lower prevalence of VL for all diseases other than DR (Figure 2-19), largely due to lower prevalence of eye diseases at equivalent ages to whites, a younger age profile, and less likelihood of developing VL once they have contracted a given eye disease. TABLE 2–39: PREVALENCE OF VL, BY CAUSE AND ETHNICITY, 2007 All ethnicities Number White % total Number AVM % total Number AMD Cataract DR Glaucoma RE/Other 89,241 133,836 29,920 24,937 539,236 10.9% 16.4% 3.7% 3.1% 66.0% 84,641 120,685 20,992 22,565 531,650 10.8% 15.5% 2.7% 2.9% 68.1% All VL 817,171 100.0% 780,534 100.0% 4,380 13,151 8,928 2,373 7,586 36,417 % total 12.0% 36.1% 24.5% 6.5% 20.8% 100.0% Note: For corresponding prevalence rates, see Table 2–40 to Table 2–45. FIGURE 2-19: PREVALENCE RATES OF VL, BY ETHNICITY AND CAUSE, 2007 3.5% All races White AVM 3.0% Prevalence (%) 3.0% 2.5% 2.5% 2.0% 2.0% 1.6% 1.5% 1.0% 0.4% 0.1% 0.5% 0.1% 0.1% 0.3% 0.2% 0.1% 0.1% 0.0% 0.1% 0.6% 0.3% 0.5% 0.0% AMD Cataract DR 0.1% Glaucoma RE/Other All VI Note: Estimates are raw prevalence rates, not age-standardised, so low AVM figures reflect low average age. The prevalence of VL is projected to increase from 2.5% of the population in 2007 to 4.0% in 2032 (Figure 2-20). In terms of numbers of people, there are projected to be almost twice as many 22 As noted earlier, Canadian Aboriginals have some of the highest rates of diabetes in the world, and Asians have some three to six times the diabetes prevalence of whites. 52 The cost of vision loss in Canada Canadians with VL in 25 years than in 2007, with VL from cataract, AMD and glaucoma all projected to increase by more than 100% over the next 25 years (114%, 113% and 117% respectively). Detailed tables underlying the projections in this section may be found in Appendix B. Summaries for 2007 are provided in Table 2–40 through to Table 2–45 at the end of this section. FIGURE 2-20: PREVALENCE OF VL, BY CAUSE, 2007-2032 4.5% 4.0% All VI Cataracts DR Glaucoma AMD RE/Other 3.5% Prevalence (%) 3.0% 2.5% 2.0% 1.5% 1.0% 0.5% 2032 2031 2030 2029 2028 2027 2026 2025 2024 2023 2022 2021 2020 2019 2018 2017 2016 2015 2014 2013 2012 2011 2010 2009 2008 2007 0.0% VL affects women more than men (Figure 2-21), reflecting greater longevity in females now and in the future. In 2007, females accounted for 58.4% of VL, by 2032, this will have fallen slightly to 56.3%. 53 The cost of vision loss in Canada FIGURE 2-21: PREVALENCE OF VL BY GENDER, 2007 TO 2032 Persons with visual Impairment (000) 1,000 900 800 700 600 500 400 300 Males Females 200 100 0 2007 2010 2015 2020 2025 2032 While the AVM share of the total population is rapidly increasing (recall Figure 2-3), the rise in this group’s share of VL at the end of the projection period is smaller than their increase in population share (Figure 2-23). This is partly due to AVM having a considerably younger age profile than the white population. It is also due to the assumption that the Visible Minorities population – which is mostly growing through migration – is not aging over the forecast period23. 1,600 100,000 90,000 White AVM 1,400 1,200 80,000 70,000 1,000 60,000 800 50,000 600 40,000 30,000 400 20,000 200 10,000 0 0 2007 23 AVM persons with visual impairment White persons with visual impairment ('000) FIGURE 2-22: PROJECTIONS OF VL, BY ETHNICITY, 2007 TO 2032 2010 2015 2020 2025 2032 This assumption is necessary as Statistics Canada does not disaggregate its growth forecasts for Visible Minorities by age cohorts. However, it is plausible. 54 The cost of vision loss in Canada FIGURE 2-23: RELATIVE SHARE OF TOTAL VL, BY ETHNICITY, 2007 TO 2032 96% White 5.0% 96% AVM 4.9% 95% 4.8% 95% 4.7% 95% 4.6% 95% 4.5% 95% 4.4% 95% 4.3% 95% AVM persons with visual impairment White persons with visual impairment ('000) 5.1% 95% 4.2% 2007 2010 2015 2020 2025 2032 55 The cost of vision loss in Canada TABLE 2–40: ALL VISION LOSS, BY AGE, GENDER AND ETHNICITY, 2007 56 Prevalent cases Males White Prevalence rate Males White AVM Total 0-4 5-9 10-14 15-19 20-24 25-29 30-34 35-39 40-44 45-49 50-54 55-59 60-64 65-69 70-74 75-79 0 0 0 0 0 0 0 0 9,369 4,964 16,752 27,740 21,291 34,347 35,808 56,857 0 0 0 0 86 24 24 87 207 64 173 1,102 805 2,207 3,112 2,380 0 0 0 0 86 24 24 87 9,577 5,028 16,924 28,842 22,096 36,555 38,920 59,237 0-4 5-9 10-14 15-19 20-24 25-29 30-34 35-39 40-44 45-49 50-54 55-59 60-64 65-69 70-74 75-79 80-84 85-89 90+ 57,986 41,730 18,606 2,540 1,146 690 60,526 42,877 19,296 80-84 85-89 90+ All Males 325,451 14,646 340,097 All Males AVM Total 0.00% 0.00% 0.00% 0.00% 0.00% 0.00% 0.00% 0.00% 0.89% 0.43% 1.66% 2.99% 2.92% 6.38% 8.19% 15.51% 0.00% 0.00% 0.00% 0.00% 0.03% 0.01% 0.01% 0.03% 0.08% 0.03% 0.09% 0.99% 0.77% 2.98% 5.92% 8.00% 0.00% 0.00% 0.00% 0.00% 0.01% 0.00% 0.00% 0.01% 0.72% 0.37% 1.40% 2.78% 2.65% 5.97% 7.94% 14.95% 24.15% 36.04% 40.26% 16.65% 19.11% 28.81% 23.70% 34.75% 41.06% 2.5% 0.5% 2.1% Female White AVM Total Female White AVM Total 0-4 5-9 10-14 15-19 20-24 25-29 30-34 35-39 40-44 45-49 50-54 55-59 60-64 65-69 70-74 75-79 0 0 0 0 0 0 0 0 9,080 4,895 16,903 28,374 21,967 36,264 40,146 71,038 0 0 0 0 49 347 345 205 389 271 487 1,568 1,182 1,715 3,895 4,232 0 0 0 0 49 347 345 205 9,469 5,166 17,390 29,942 23,148 37,979 44,041 75,270 0-4 5-9 10-14 15-19 20-24 25-29 30-34 35-39 40-44 45-49 50-54 55-59 60-64 65-69 70-74 75-79 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.9% 0.4% 1.7% 3.0% 2.9% 6.4% 8.2% 15.5% 0.0% 0.0% 0.0% 0.0% 0.0% 0.1% 0.1% 0.1% 0.1% 0.1% 0.2% 1.3% 1.1% 1.9% 6.1% 11.5% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.7% 0.4% 1.4% 2.8% 2.7% 5.8% 7.9% 15.2% 80-84 85-89 90+ All Females All Persons 89,952 83,576 52,888 4,114 1,760 1,213 94,066 85,336 54,101 24.1% 36.0% 40.3% 21.5% 25.4% 31.0% 24.0% 35.4% 40.6% 455,083 21,771 476,854 3.4% 0.7% 2.9% 780,534 36,417 816,951 80-84 85-89 90+ All Females All Persons 3.0% 0.6% 2.5% The cost of vision loss in Canada TABLE 2–41: CATARACT VISION LOSS, BY AGE, GENDER AND ETHNICITY, 2007 Prevalent cases Males White Prevalence rate Males White AVM Total 0-4 5-9 10-14 15-19 20-24 25-29 30-34 35-39 40-44 45-49 50-54 55-59 60-64 65-69 70-74 75-79 80-84 85-89 90+ 0 0 0 0 0 0 0 0 0 0 0 783 78 873 3,173 8,692 13,186 10,086 7,010 0 0 0 0 0 0 0 0 0 0 0 198 63 229 1,261 626 978 375 334 0 0 0 0 0 0 0 0 0 0 0 980 141 1,102 4,434 9,319 14,164 10,462 7,344 0-4 5-9 10-14 15-19 20-24 25-29 30-34 35-39 40-44 45-49 50-54 55-59 60-64 65-69 70-74 75-79 80-84 85-89 90+ All Males 43,882 4,063 47,945 All Males Female White AVM Total 0-4 5-9 10-14 15-19 20-24 25-29 30-34 35-39 40-44 45-49 50-54 55-59 60-64 65-69 70-74 75-79 80-84 85-89 90+ All Females All Persons 0 0 0 0 0 0 0 0 0 0 0 801 80 921 3,557 10,860 20,455 20,201 19,927 0 0 0 0 0 0 0 0 0 0 0 166 58 450 2,334 1,791 2,458 969 861 0 0 0 0 0 0 0 0 0 0 0 967 138 1,371 5,892 12,651 22,914 21,170 20,788 76,803 9,088 85,891 120,685 13,151 133,836 AVM Total 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.1% 0.0% 0.2% 0.7% 2.4% 5.5% 8.7% 15.2% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.2% 0.1% 0.3% 2.4% 2.1% 6.4% 6.3% 13.9% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.1% 0.0% 0.2% 0.9% 2.4% 5.5% 8.5% 15.6% 0.3% 0.1% 0.3% Female White AVM Total 0-4 5-9 10-14 15-19 20-24 25-29 30-34 35-39 40-44 45-49 50-54 55-59 60-64 65-69 70-74 75-79 80-84 85-89 90+ All Females All Persons 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.1% 0.0% 0.2% 0.7% 2.4% 5.5% 8.7% 15.2% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.1% 0.1% 0.5% 3.6% 4.9% 12.8% 14.0% 22.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.1% 0.0% 0.2% 1.1% 2.6% 5.8% 8.8% 15.6% 0.6% 0.3% 0.5% 0.5% 0.2% 0.4% 57 The cost of vision loss in Canada TABLE 2–42: DR VISION LOSS, BY AGE, GENDER AND ETHNICITY, 2007 Prevalent cases Males White AVM Total Prevalence rate Males White AVM Total 0-4 5-9 10-14 15-19 20-24 25-29 30-34 35-39 40-44 45-49 50-54 55-59 60-64 65-69 70-74 75-79 80-84 85-89 90+ 0 0 0 0 0 0 0 0 0 0 881 1,130 1,141 879 447 1,623 1,881 792 270 0 0 0 0 86 24 24 87 87 55 53 610 575 593 421 503 258 94 48 0 0 0 0 86 24 24 87 87 55 933 1,740 1,717 1,472 869 2,125 2,138 886 318 0-4 5-9 10-14 15-19 20-24 25-29 30-34 35-39 40-44 45-49 50-54 55-59 60-64 65-69 70-74 75-79 80-84 85-89 90+ 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.1% 0.1% 0.2% 0.2% 0.1% 0.4% 0.8% 0.7% 0.6% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.6% 0.6% 0.8% 0.8% 1.7% 1.7% 1.6% 2.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.1% 0.2% 0.2% 0.2% 0.2% 0.5% 0.8% 0.7% 0.7% All Males 9,043 3,517 12,560 All Males 0.1% 0.1% 0.1% Female White AVM Total Female White AVM Total 0-4 5-9 10-14 15-19 20-24 25-29 30-34 35-39 40-44 45-49 50-54 55-59 60-64 65-69 70-74 75-79 80-84 85-89 90+ All Females All Persons 0 0 0 0 0 0 0 0 0 0 889 1,155 1,177 928 502 2,028 2,917 1,586 768 0 0 0 0 49 347 345 205 206 232 224 842 794 616 435 616 320 120 61 0 0 0 0 49 347 345 205 206 232 1,112 1,997 1,971 1,544 937 2,643 3,237 1,706 829 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.1% 0.1% 0.2% 0.2% 0.1% 0.4% 0.8% 0.7% 0.6% 0.0% 0.0% 0.0% 0.0% 0.0% 0.1% 0.1% 0.1% 0.1% 0.1% 0.1% 0.7% 0.7% 0.7% 0.7% 1.7% 1.7% 1.7% 1.6% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.1% 0.2% 0.2% 0.2% 0.2% 0.5% 0.8% 0.7% 0.6% 11,950 5,411 17,360 0.1% 0.2% 0.1% 20,992 8,928 29,920 0-4 5-9 10-14 15-19 20-24 25-29 30-34 35-39 40-44 45-49 50-54 55-59 60-64 65-69 70-74 75-79 80-84 85-89 90+ All Females All Persons 0.1% 0.1% 0.1% 58 The cost of vision loss in Canada TABLE 2–43: GLAUCOMA VISION LOSS, BY AGE, GENDER AND ETHNICITY, 2007 Prevalent cases Males White AVM Total Prevalence rate Males White AVM Total 0-4 5-9 10-14 15-19 20-24 25-29 30-34 35-39 40-44 45-49 50-54 55-59 60-64 65-69 70-74 75-79 80-84 85-89 90+ 0 0 0 0 0 0 0 0 0 0 0 0 0 885 879 1,246 3,643 1,533 568 0 0 0 0 0 0 0 0 0 0 0 0 0 402 532 118 285 78 37 0 0 0 0 0 0 0 0 0 0 0 0 0 1,288 1,410 1,364 3,928 1,611 605 0-4 5-9 10-14 15-19 20-24 25-29 30-34 35-39 40-44 45-49 50-54 55-59 60-64 65-69 70-74 75-79 80-84 85-89 90+ 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.2% 0.2% 0.3% 1.5% 1.3% 1.2% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.5% 1.0% 0.4% 1.9% 1.3% 1.5% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.2% 0.3% 0.3% 1.5% 1.3% 1.3% All Males 8,753 1,453 10,206 All Males 0.1% 0.0% 0.1% Female White AVM Total Female White AVM Total 0-4 5-9 10-14 15-19 20-24 25-29 30-34 35-39 40-44 45-49 50-54 55-59 60-64 65-69 70-74 75-79 80-84 85-89 90+ All Females All Persons 0 0 0 0 0 0 0 0 0 0 0 0 0 935 985 1,556 5,651 3,069 1,615 0 0 0 0 0 0 0 0 0 0 0 0 0 164 209 297 177 50 24 0 0 0 0 0 0 0 0 0 0 0 0 0 1,099 1,194 1,853 5,828 3,119 1,639 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.2% 0.2% 0.3% 1.5% 1.3% 1.2% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.2% 0.3% 0.8% 0.9% 0.7% 0.6% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.2% 0.2% 0.4% 1.5% 1.3% 1.2% 13,812 920 14,731 0.1% 0.0% 0.1% 22,565 2,373 24,937 0-4 5-9 10-14 15-19 20-24 25-29 30-34 35-39 40-44 45-49 50-54 55-59 60-64 65-69 70-74 75-79 80-84 85-89 90+ All Females All Persons 0.1% 0.0% 0.1% 59 The cost of vision loss in Canada TABLE 2–44: AMD VISION LOSS, BY AGE, GENDER AND ETHNICITY, 2007 Prevalent cases Males White Prevalence rate Males White AVM Total 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.1% 0.2% 1.7% 2.3% 8.8% 13.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.1% 0.5% 1.9% 4.1% 7.0% 8.9% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.1% 0.3% 1.7% 2.4% 8.6% 13.2% 0.2% 0.1% 0.2% AVM Total 0-4 5-9 10-14 15-19 20-24 25-29 30-34 35-39 40-44 45-49 50-54 55-59 60-64 65-69 70-74 75-79 80-84 85-89 90+ 0 0 0 0 0 0 0 0 0 0 0 0 0 436 968 6,236 5,537 10,157 5,996 0 0 0 0 0 0 0 0 0 0 0 0 0 83 264 551 624 420 214 0 0 0 0 0 0 0 0 0 0 0 0 0 519 1,232 6,787 6,161 10,577 6,210 0-4 5-9 10-14 15-19 20-24 25-29 30-34 35-39 40-44 45-49 50-54 55-59 60-64 65-69 70-74 75-79 80-84 85-89 90+ All Males 29,330 2,156 31,486 All Males Female White AVM Total Female White AVM Total 0-4 5-9 10-14 15-19 20-24 25-29 30-34 35-39 40-44 45-49 50-54 55-59 60-64 65-69 70-74 75-79 80-84 85-89 90+ All Females All Persons 0 0 0 0 0 0 0 0 0 0 0 0 0 461 1,085 7,791 8,590 20,342 17,043 0 0 0 0 0 0 0 0 0 0 0 0 0 128 341 611 600 360 184 0 0 0 0 0 0 0 0 0 0 0 0 0 589 1,427 8,402 9,190 20,702 17,227 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.1% 0.2% 1.7% 2.3% 8.8% 13.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.1% 0.5% 1.7% 3.1% 5.2% 4.7% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.1% 0.3% 1.7% 2.3% 8.6% 12.9% 55,311 2,225 57,536 0.4% 0.1% 0.3% 84,641 4,380 89,022 0-4 5-9 10-14 15-19 20-24 25-29 30-34 35-39 40-44 45-49 50-54 55-59 60-64 65-69 70-74 75-79 80-84 85-89 90+ All Females All Persons 0.3% 0.1% 0.3% 60 The cost of vision loss in Canada TABLE 2–45: RE/OTHER VISION LOSS, BY AGE, GENDER AND ETHNICITY, 2007 Prevalent cases Males White Prevalence rate Males White AVM Total 0-4 5-9 10-14 15-19 20-24 25-29 30-34 35-39 40-44 45-49 50-54 55-59 60-64 65-69 70-74 75-79 80-84 85-89 90+ 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.9% 0.4% 1.6% 2.8% 2.8% 5.8% 6.9% 10.7% 14.0% 16.5% 10.3% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.1% 0.3% 0.2% 1.2% 1.2% 2.0% 2.6% 3.0% 2.4% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.7% 0.4% 1.3% 2.5% 2.4% 5.3% 6.3% 10.0% 13.4% 15.7% 10.3% 1.8% 0.1% 1.5% AVM Total 0 0 0 0 0 0 0 0 9,369 4,964 15,871 25,828 20,072 31,274 30,341 39,060 33,739 19,163 4,762 0 0 0 0 0 0 0 0 120 9 120 294 167 900 634 582 395 179 57 0 0 0 0 0 0 0 0 9,490 4,973 15,991 26,122 20,239 32,174 30,975 39,642 34,134 19,342 4,819 All Males 234,443 3,457 237,900 Female White AVM Total Female White AVM Total 0-4 5-9 10-14 15-19 20-24 25-29 30-34 35-39 40-44 45-49 50-54 55-59 60-64 65-69 70-74 75-79 80-84 85-89 90+ All Females All Persons 0 0 0 0 0 0 0 0 9,080 4,895 16,015 26,418 20,709 33,020 34,017 48,803 52,338 38,378 13,535 0 0 0 0 0 0 0 0 184 39 263 560 330 358 575 917 559 260 83 0 0 0 0 0 0 0 0 9,264 4,934 16,278 26,978 21,039 33,378 34,592 49,720 52,897 38,638 13,617 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.9% 0.4% 1.6% 2.8% 2.8% 5.8% 6.9% 10.7% 14.0% 16.5% 10.3% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.1% 0.0% 0.1% 0.5% 0.3% 0.4% 0.9% 2.5% 2.9% 3.8% 2.1% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.7% 0.4% 1.3% 2.5% 2.4% 5.1% 6.2% 10.0% 13.5% 16.0% 10.2% 297,207 4,129 301,336 2.2% 0.1% 1.8% 531,650 7,586 539,236 0-4 5-9 10-14 15-19 20-24 25-29 30-34 35-39 40-44 45-49 50-54 55-59 60-64 65-69 70-74 75-79 80-84 85-89 90+ All Females All Persons 2.0% 0.1% 1.6% 0-4 5-9 10-14 15-19 20-24 25-29 30-34 35-39 40-44 45-49 50-54 55-59 60-64 65-69 70-74 75-79 80-84 85-89 90+ All Males 61 The cost of vision loss in Canada 3. HEALTH SYSTEM EXPENDITURE After ascertaining the prevalence of VL from the various eye disorders, costs to the Canadian economy can be calculated. Financial costs included direct health system expenditure (medicines, surgery, lenses, and so on) and indirect costs (for example, lower levels of employment for visually impaired people and time spent by caregivers for people with VL). While available data from Canada are not sufficient to uniformly adopt a ‘top-down’ approach (that is, national expenditure on all forms of treatment for visually impairing eye conditions) or ‘bottom-up’ estimates (known costs and quantities of specific eye care procedures), using a combination approach enables a reasonable estimate of total health system expenditure. 3.1 TOTAL EXPENDITURE ON ‘VISION CARE’ The Canadian Institute for Health Information (CIHI) tracks health expenditure on its National Health Expenditure (NHEX) database, including expenditure on ‘vision care’. The vision care category includes expenditures for the professional services of optometrists and dispensing opticians, as well as expenditures for eyeglasses and contact lenses. Expenditure on vision care was nearly $3.5 billion in 200724, representing 2.2% (Figure 3-1) of all health system expenditure ($160.1 billion in 2007). FIGURE 3-1: CANADIAN HEALTH SYSTEM EXPENDITURE, 2007 (% OF TOTAL) Other Health Spending 6.1% Administration 3.6% Public Health 5.8% Hospitals 28.4% Capital 4.6% Drugs 16.8% Other Institutions 10.4% Other Professional Services 8.6% Vision Care 2.2% Physicians 13.4% Source: CIHI NHEX. Apart from differentiating the services of particular types of health professionals (eg, optometrists), the NHEX does not divide expenditure by disease category. 24 Expenditure for 2007 ($3,483m) was still a provisional forecast at time of drafting. 62 The cost of vision loss in Canada Expenditure on health care in Canada has been growing rapidly – considerably faster than Gross Domestic Product. After adjusting for inflation, health care spending grew at an average annual real rate of 3.8% between 1975 and 1991, by 0.8% per annum from 1991 to 1996 and by 5.1% from 1996 to 2003. However, expenditure on vision care has risen even faster, rising from 1.8% of the total in 1975 to 2.2% in 2007 (Figure 3-2). FIGURE 3-2: EXPENDITURE ON VISION CARE, CANADA, 1975-2007 1,000,000 100,000 1,000 Vision Care Services Total 10,000 2007 2005 2003 2001 1999 1997 1995 1993 1991 1989 1987 1985 1983 1981 1979 1977 1,000 1975 100 Total health expenditure ($m) Vision care expenditure ($m) 10,000 Source: CIHI NHEX. NHEX data from earlier years (before 2007) provides more detail than are currently available for 2007. Total health system expenditure reported by the NHEX for Canada was $141.2 billion in 2005. The majority of this, $99.1 billion (or 70.1%) was publicly funded, with the remaining $42.2 billion (29.9%) privately funded. The NHEX reports that in 2005, nearly all Canadian public expenditure (93.6%) came from Provincial and Territory governments. Only 4.3% came from the Federal Government, with municipal governments and worker’s compensation funds comprising the remaining 2.1%. Households accounted for the majority (58.1%) of total private expenditure on health care in Canada in 2005. Private health insurance entities constituted 29.2%, and ‘other’ (including hospital nonpatient revenue, capital expenditures for privately owned facilities and health research) made up the remaining 12.7%. Expenditure on vision care totalled $3.19 billion in 2005. In 2003 when the total was $2.64 billion, the NHEX showed that private spending on vision care in Canada was $2.44 billion, whereas public spending only amounted to $200 million. Of private expenditure, households contributed $1.91 billion and private health insurance $0.53 million. 3.2 EXPENDITURE ON PARTICULAR EYE DISORDERS While ‘vision care’ is only a small component of overall health system expenditure on visually impairing conditions, it can be supplemented from other sources. In a number of cases, detailed 63 The cost of vision loss in Canada information about the costs of certain eye procedures are available. Less frequently, numbers of eye procedures performed are also available. Where both are available, ‘bottom up’ calculations of expenditure can be estimated. CIHI’s National Grouping System (NGS) attempts to provide reasonably comparable and consistent statistics on the utilization, cost and distribution of physicians’ services for which payment was made on a fee-for-service basis by provincial and territorial medical care insurance plans. CIHI (2007) data on eye examinations and cataract surgery summed to around $144 million in 2004-05 (Table 3–1). Assuming expenditure on these procedures has risen by the same amount as total health system expenditure, this figure would have risen to $153 million by 2007. TABLE 3–1: TOTAL EXPENDITURE ON CERTAIN EYE PROCEDURES, 2004-05 Procedure Eye Examinations Cataract Surgery Total Number Average $/case Expenditure $m 373,148 284,523 657,671 $41.44 $452.30 $219.15 $15.5 $128.7 $144.2 Source: CIHI (2007). Note $/case is derived from the other two columns. Additionally, some partial information is available on drug expenditure from Health Canada (2002a) The Economic Burden of Illness in Canada 1998. Drug expenditure on two categories of eye disorders – glaucoma and conjunctiva disorders – totalled $143.2 million in 1998 (Table 3–2). Given the NHEX shows expenditure on drugs has increased by 214% since then, proportionally, this figure in 2007 would be $307 million (Table 3–3). TABLE 3–2: DRUG EXPENDITURE ON NERVOUS SYSTEM AND SENSE ORGAN DISORDERS, 1998 $m Disorder Glaucoma Conjunctiva disorders Ear infections Parkinson’s disease Other nervous system and sense organ disorders Sub-total for nervous system and sense organ disorders 54.7 88.5 92.7 24.1 276.4 536.4 Total for all diseases 12,385.2 Source: Health Canada (2002a). Health Canada (2002a) gives a breakdown of the ICD-10 block ‘Nervous System and Sense Organ Disorders’, of which vision conditions are a major component. Unfortunately Health Canada were unable to supply more detailed data than as provided in Table 3–3, to isolate the vision component. TABLE 3–3: EXPENDITURE ON NERVOUS SYSTEM AND SENSE ORGAN DISORDERS (1998) $m Hospital Care Drugs Physician Care Research Total 1,425.6 536.4* 824.8 35.7 2,822.5 % of total health system expenditure 5.20% 4.30% 7.10% 0.20% 3.36% Source: Health Canada (2002a). * Matches the Table 3-2 sub-total. 64 The cost of vision loss in Canada CIHI (2005) Exploring the 70/30 Split: How Canada’s Health System is Financed, provides quite detailed information on the costs of a selected range of hospital procedures. The only procedure listed there relevant to VL – ‘Retinal procedures’ – averaged $2,538 in 2003 (around half the cost of most procedures). Charts in the same document show that these costs can be broken down to provincial level. The CIHI website shows a casemix spreadsheet with the following reporting (Table 3–4) of eye operations by volume in 2000-01. This, together with the above data on cost of retinal procedures, allows an estimate of the cost and quantity of retinal procedures (4,126 cases in 2000/01). A more detailed breakdown of hospital expenditures is not possible. TABLE 3–4: FREQUENCY OF SELECTED HOSPITAL PROCEDURES (2001)25 Case Mix Description Retinal procedures Orbital procedures Lens insertion Other ophthalmic dx Major eye infections Other intraocular procedures Other ophthalmic proc Extraocular procedures Iris and lens procedures Hyphema Volume FY00/01 4,126 2,889 1,284 1,134 847 715 492 289 110 95 Source: CIHI secure.cihi.ca/cihiweb/en/downloads/Casemix_ICDimpact_AppA_CMG_02_03.xls For specialist consultations, data on Medicare rebates are available for some provinces. Rebates for ophthalmological procedures from the Ontario Ministry of Health and Long-Term Care’s Schedule of Benefits for Physician Services 2006 are shown in Table 3–5. However, for these data to be useful there is also a need to know the numbers of each procedure performed. TABLE 3–5: REBATES FOR CERTAIN OPHTHALMOLOGICAL PROCEDURES IN ONTARIO (2006) Ophthalmological Listing A235 Consultation A935 Special surgical consultation (see General Preamble GP17) A236 Repeat consultation A233 Specific assessment A234 Partial assessment A237 Periodic Oculo-visual Assessment A115 Major eye examination A230 Orthoptic assessment A250 Retinopathy of prematurity assessment A252 Initial vision rehabilitation assessment A251 Special ophthalmologic assessment Cost ($) 71.30 132.50 45.85 42.15 22.45 42.15 42.15 25.00 120.00 240.00 120.00 Source: Ontario Ministry of Health and Long-Term Care’s Schedule of Benefits for Physician Services 2006. 25 COS advise that it is ‘totally unbelievable’ that there are four times as many retinal procedures as lens insertions (and in Australia it is more like the other way round). Accordingly, information from this table is regarded as unreliable and not utilized for final costings. It is still included, however, as part of the census of information available from official sources in Canada. 65 The cost of vision loss in Canada Cruess et al (2007) provide a comprehensive coverage of the average costs involved in treating AMD in Canada (Table 3–6), which can be used with prevalence data to estimate the total cost of AMD. TABLE 3–6: AVERAGE TREATMENT COSTS FOR NEOVASCULAR AMD (2005) Treatment Cost ($) Verteporfin, one eye only Simultaneous verteporfin treatment, both eyes Intravitreal coriscosteroids, per eye Photodynamic therapy with intravitreal steroid injection $2,112 $2,266 $183 $308 Source: Cruess et al (2007). Ray et al (2005) provide costs for both cataract surgery and retinal laser treatment for DR in Canada of $1,323 and $709 in 2003. Interestingly, these procedures were substantially less expensive in Canada than the same operations in Australia - $2,061 and $2,237 respectively.26 Iskedjian et al (2003) conducted an Ontario-based costing analysis of glaucoma in Canada and estimated the total cost of procedures associated with the treatment of glaucoma to be $344 for mild, $420 for moderate, and $511 for severe forms of glaucoma in 2001. These estimates included the cost of the procedure itself, physician’s fee, assistant’s fee, and the anaesthetist’s fee. Costs associated with hospital resources and medications were not included. 3.3 TOTAL HEALTH SYSTEM EXPENDITURE 3.3.1 HEALTH SYSTEM EXPENDITURE, TOP DOWN This top down estimate relies primarily on two sources: Health Canada’s 2002 publication The Economic Burden of Illness in Canada 1998 and CIHI’s National Health Expenditure Database (NHEX), and is calculated as outlined below. Total health system expenditure in 2007 was $160.1 billion dollars. Expenditure on ‘nervous system and sense disorders’ in 1998 was 3.36% (from Table 3–3) of health system expenditure (Health Canada, 2002a). However, health system expenditure as defined in this source only covers hospitals, physicians, drugs and research. Assuming nervous system and sense disorders are also responsible for the same ratio (3.36%) of the total health system expenditure reported for 2007 by the NHEX ($160.1 billion) then total health system expenditure on nervous system and sense disorders in 2007 would be $5.38 billion. This provides an upper limit on expenditure on VL (for the above categories). Health Canada (2002a) does not provide any further breakdowns, except for drugs (Table 3– 2). Within drugs there are a number of subcategories that can be attributable to VL (noting that the category ‘other’ accounts for the majority of expenditure). Specifically, expenditure on glaucoma and conjunctiva disorders can be attributed to VL, ear infections to other sense organ disorders, and Parkinson’s to nervous system disorders. Thus represented, VL accounts for 55.1% of such drug expenditure as it is able to be attributed to separately identified categories; other sense organ disorders (ear infections) account for 35.7% and nervous system disorders (Parkinson’s) account for 9.3%. It is assumed that expenditure in ‘other’ would have the same distribution between these identifiable categories. 26 In the original article, all costs were in Euros, converted to Canadian dollars at then prevailing exchange rates. 66 The cost of vision loss in Canada Assuming that, if VL accounts for 55.1% of all drug expenditure on ‘nervous system and sense disorders’ then VL would also account for the same proportion of health system expenditure on nervous system and sense disorders, and 55.1% of $5.38 billion equals $2.97 billion. This provides an upper limit for VL expenditure under the hospital, research, physicians and drug categories. The NHEX also provides explicit expenditure for the professional services category under ‘Vision Care’,27 which includes optometrists, ophthalmologists, glasses and contact lenses, of $3.48 billion. Adding vision care to the $5.38 billion estimate of expenditure on hospitals, physicians, drugs and research yields a total of $6.45 billion in 2007. The NHEX further shows that expenditure on ‘Other institutions’ is composed of nursing homes (90%) and mental institutions (10%). Access Economics (2006) calculated that 3.0% of US nursing home patients had been institutionalized due to VL. Thus, 2.7% (=3.0% * 90%) of the total ‘other institutions’ of $16.7 billion (NHEX) is estimated to be due to VL, or $448.8 million. This still leaves an amount to be calculated for public health, administration, capital, and other expenditure ‘not elsewhere classified’. These categories collectively account for 20% of total health system expenditure (Figure 3-1). Thus, given the categories already calculated account for 80% of health system expenditure, these remaining categories are equivalent to a quarter of those already calculated (=20% / 80%), or $1.7 billion Thus, a top down estimate of health system expenditure on VL in Canada for 2007 is $8.64 billion. TABLE 3–7: ESTIMATED VL HEALTH SYSTEM EXPENDITURE (TOP DOWN), 2007 Type of cost Hospital Physicians Pharmaceuticals Vision Care (optometry, ophthalmology and lenses) Research Other Institutions Other (capital, public health, administration, other institutions and professional services) Total 3.3.2 Total ($m) 1,497.7 866.5 563.5 3,483.7 37.5 444.8 1,740.3 $8,637.9 HEALTH SYSTEM EXPENDITURE, BOTTOM UP For a bottom up approach, estimates were undertaken for each of the five major eye diseases, either for total expenditure, or by the categories covered under the top-down approach, but for each individual disease. For AMD, Cruess et al (2008) estimated the total to society of AMD in Canada was $1.12 billion in 2005. For the average patient, medical costs accounted for over three quarters of this figure (76.7%) and non-medical costs (primarily aids, equipment and carers) the remainder (23.3%). Subtracting non-medical costs proportionally leaves health system expenditure of $858.7 million. As 27 For total health system expenditure, the NHEX divides Professional Services is divided into two subcategories ‘Vision Care’ and ‘Other’. 67 The cost of vision loss in Canada these estimates apply to 2005, allowing for cumulative inflationary increases of 4.7% yields a total for 2007 health system expenditure of $898.9 million. For RE, given this is the only form of VL correctable by lenses, the assumption was made most of the NHEX category ‘vision care’ would be attributable to RE. Conversely, it was also assumed that RE required little in the way of hospital care, physicians, drugs or the other categories in Table 3–7. Thus, expenditure on RE would be around $3.48 billion. For glaucoma, following the methodology adopted in the top-down approach, the ratio of glaucoma drug expenditure to total nervous drug expenditure (10.2%) was assumed to hold for glaucoma’s share of total ‘nervous system and sense organ disorders’ health system expenditure. Nervous system and sense disorders in turn were (3.36%) of total health system expenditure. This yields a total of $549 million for glaucoma. Total expenditure on cataract surgery is estimated at $136.6 million, taking the $128.7 million in 2004-05 from Table 3–1 and allowing for inflation to 2007. Assuming that most such surgery takes place in hospitals, then given hospitals account for 28.4% of total health system expenditure, if the same ratio holds for cataract, total health system expenditure for cataract would be $481 million. For diabetic retinopathy (DR), given there is only one frequency of procedure number, which COS advise is not plausible, costs are assumed to be the same as the average for the other diseases ($6,875 per person per year), which for the total of 29,920 people with VL from DR, gives a total of $205.71 million. Thus, estimating from the bottom up, total health system expenditure on VL was $5.62 billion in Canada in 2007. As with the top-down estimate, this figure needs to be scaled up to account for factors such as capital expenditure, research, public health and other unallocated health expenditure. For consistency, the same mark-up (25.2%) is used, giving a total bottom-up estimate of $7.04 billion. 3.3.2.1 SUMMARY The bottom-up estimate above is around 18.5% lower than the top-down estimate derived earlier. Most of this difference would be due to the fact that the bottom-up estimate only includes the ‘big five’ eye diseases (cataract, DR, glaucoma, AMD, RE). For example, Maberley et al (2006) in their study of VL in one Canadian city found that 12% of VL was caused by visual pathway disease (which is not included in the bottom up estimates). Accordingly, while Access Economics has a preference to err on the side of caution, in this case the top-down estimate is considered more reliable. Thus the total cost of VL-related health expenditure in Canada is estimated as $8,637.9 million in 2007. This equates to $10,570 per person with VL per annum. 68 The cost of vision loss in Canada 4. OTHER FINANCIAL COSTS In addition to health system costs, VL also imposes a number of other important financial costs on society and the economy, including the following. Productivity losses of people with VL comprise those from lower employment participation, absenteeism and/or premature mortality. Carer costs comprise the value of care services provided in the community primarily by informal carers and not captured in health system costs. Other costs comprise the cost of aids, home modifications and other pertinent financial costs not captured elsewhere. Transfer costs comprise the deadweight loss (DWL) associated with government transfers such as taxation revenue forgone, welfare and disability payments. It is important to make the economic distinction between real and transfer costs. Real costs use up real resources, such as capital or labour, or reduce the economy’s overall capacity to produce goods and services. Transfer payments involve payments from one economic agent to another that do not use up real resources eg, a disability support pension or taxation revenue. Data on other financial costs are drawn from a variety of sources eg, the literature (focusing on Canadian literature but sometimes supplemented by other international material). 4.1 PRODUCTIVITY LOSSES Productivity losses are the cost of production that is lost when people with VL are unable to work because of the condition. They may work less than they otherwise would (either being employed less, being absent more often or being less productive while at work) or they may die prematurely. This represents a real cost to the Canadian economy. Access Economics adopts a human capital approach to measurement of productivity losses in developed countries. 4.1.1 EMPLOYMENT PARTICIPATION Some insight into the employment impact of VL is provided by CNIB (2005). A survey of people living with vision loss found that the employment rate among those of working age was only 24.7% compared to 67.6% for the general population of the same age (Table 4–2). The chances of being employed are thus almost two-thirds (64%) lower for someone who is visually impaired. In addition to 24.7% who were employed, 49.2% listed themselves as unemployed, while the remaining 26.1% were ‘retired’ or ‘other’ and are assumed to be not participating in the labour force. Thus, of those actively participating in the labour force, 67% of people with VL describe themselves as unemployed. Of those who were employed, 63% were working full time, but only 29% had a permanent position. Alternate data from the 2001 PALS indicates that the employment rate among those with VL was 32%. Given the PALS survey has a larger sample size than the CNIB survey, the former is preferred. On PALS data, people with VL are around half as likely to be employed as those with full sight (53% lower). This reduced employment result was then combined with employment rates for each respective agegender group (Table 4–2) to calculate, from the number of people with VL in that age group, how many would be unemployed. The lost productivity for those unemployed due to VL was then 69 The cost of vision loss in Canada measured by the average weekly earnings (AWE) of $855.06 that they would have otherwise been earning (Table 4–1).28 TABLE 4–1: ESTIMATED AWE, BY AGE AND GENDER, 2007 Age Male Female Persons 15-19 20-24 25-34 35-44 45-54 55-59 60-64 65+ Total $264.49 $576.08 $926.61 $926.61 $1,096.00 $1,096.00 $1,095.09 $1,095.09 $1,036.21 $192.03 $493.65 $686.58 $686.58 $670.28 $670.28 $681.15 $681.15 $645.82 $227.35 $537.13 $817.92 $817.92 $897.63 $897.63 $890.38 $890.38 $855.06 Source: Derived from Statistics Canada Employment, Earnings and Hours, Cat No 72-002-XIB. TABLE 4–2: PERCENTAGE OF POPULATION EMPLOYED, BY AGE AND GENDER Age Male Female 15-19 years 20-24 years 25-34 years 35-44 years 45-54 years 55-64 years 45% 73% 86% 88% 85% 64% 49% 70% 78% 79% 78% 51% Source: Statistics Canada, Labor force characteristics by age and sex http://www40.statcan.ca/l01/cst01/labor20a.htm The annual cost of lost earnings due to reduced employment is thus estimated as $4.06 billion in 2007. 4.1.2 ABSENTEEISM FROM PAID AND UNPAID WORK In addition to workforce separation, people with VL may be absent from work more often as a result of their impairment. Our literature search was unable to locate published works on such absenteeism rates for people with VL in Canada. However, Access Economics (2006) calculated (from the National Health Interview Survey-Disability data set) that in the US, VL was shown to result in an additional 4.1 days off work per annum. This estimate could also be applied to Canada, noting it is small ($155 per person with VL) relative to the productivity cost associated with lower workforce participation. In cases of absenteeism, employers often choose to make up lost production through overtime employment of another employee that attracts a premium on the ordinary wage. The overtime premium represents lost employer profits. On the other hand, the overtime premium also indicates how much an employer is willing to pay to maintain the same level of production. Thus, if overtime employment is not used, the overtime premium also represents lost employer profits due to lost 28 As Statistics Canada does not break down AWE for each age-gender group, these were estimated from the distribution in Australia, due to the similarities (see footnote 11). 70 The cost of vision loss in Canada production. While productivity remains at the same level, the distribution of income between wages and profits changes29. For this study it is assumed that the overtime rate is 40%30. According to traditional microeconomic theory (in particular the work of Gary Becker in the 1960s), people will work until they are indifferent between the marginal value of the income earned relative to the personal value of the time sacrificed that could be used for unpaid domestic work or leisure. However no-one else tends to value the individual's leisure similarly. The typical approach to overcome this problem is to value leisure time at a discounted proportion of earnings which takes into account taxes that reduce the effective income from work and restrictions on the amount of time that can be used for work (for both biological and governmental regulation reasons). Access Economics assumes that visually impaired people incur the same loss of time from unpaid work (‘leisure’) as from paid work, but that the value of this time is 30% of paid work. Based on these parameters and the AWE for each age-gender group, Access Economics estimates that in 2007, the total cost of absenteeism due to VL is $231.7 million. Of this, $22.8 million is the workplace absenteeism cost borne by the employee, $122.5 million is the workplace absenteeism cost borne by the employer, and $86.5 million is the value of absenteeism from unpaid work. 4.1.3 PRESENTEEISM VL can also affect a person’s ability to work effectively while at work. Presenteeism can be estimated by multiplying the number of days worked with VL by the percentage reduction in effectiveness on days worked with VL. Workers with VL must have productivity reasonably close to their sighted counterparts; otherwise they would not continue to be employed. With the right equipment, they should be just as productive as anyone else. However, the CNIB survey found that around three-quarters (73.8%) of workers with VL indicated that their workplace was taking some measures to accommodate them; mostly in the form of adapted equipment, flexible scheduling and modified responsibilities. Around a quarter (23.5%) indicated that they did not receive job accommodation measures that they needed, with the greatest unmet need being for adaptive computers. Daum et al (2004) in a study of productivity and visual status in the US found that vision loss reduced productivity in the workforce by between 2.5% and 28.9%. Taking a simple average of an 15.7% reduction in productivity, and applying this to the 23.5% of VL workers without proper equipment, yields an estimated overall lower productivity for VL workers of 3.7%. Such a low level of productivity highlights the significant impact of VL on employment outcomes. Given these results, Access Economics estimates that in 2007, the total cost of ‘presenteeism’ (lower productivity while at work) due to VL is $133.9 million. 29 While the opportunity cost of any overtime employment of another employee is implicitly taken into account through the overtime premium, this methodology does not allow for the choice to use salaried or part-time employees to make up the production at ordinary or no additional wage costs. However given that workers are assumed to value their leisure time at 30% of their earnings, the difference in estimated economic costs if this choice is taken into account would be small – the only difference would be that ‘society’ would incur these costs rather than the ‘employer’. 30 Based on the lower bound of workplace injuries literature - NOHSC assumed an overtime rate of 40% (Access Economics 2004b). 71 The cost of vision loss in Canada 4.1.4 PREMATURE MORTALITY The production loss arising from premature mortality associated with VL through falls and depression is calculated as the expected remaining lifetime earnings multiplied by the number of people who died prematurely who would otherwise have been employed. As discussed in Section 5.2.2, the estimated number of deaths due to VL is 313. Since most (98%) of these deaths are in the 75+ age group where employment rates are low, lifetime earnings lost are not large. The estimated annual cost due to lost productivity from premature death due to VL is $3.4 million in 2007. Premature death also leads to additional search and hiring costs for replacement workers. These are estimated as the number of people with VL who die prematurely (by age and gender) multiplied by their chance of being employed multiplied by the search and hiring cost brought forward three years (the search and hiring cost is estimated as 26 weeks at AWE and the three year bring forward reflects average staff turnover rates). Since premature mortality costs are very low, these costs are tiny. In 2007, additional search and hiring costs are estimated at only $9,040 for people with VL, based on the present value of bringing forward three years of average cost of staff turnover (26 weeks at AWE). 4.1.5 FUNERAL COSTS The ‘additional’ cost of funerals borne by family and friends of people with VL is based on the additional likelihood of death associated with VL in the period that the person experiences it. However, some people (particularly older people) would have died during this time anyway. Eventually everyone must die and thus incur funeral expenses – so the true cost is the cost brought forward (adjusted for the likelihood of dying anyway in a given year). The most recent official data on funeral costs from are from 1991 (Statistics Canada, 1998), at which point an average funeral cost around $3,510. Updating this to allow for inflation to 2007 yields a current cost of $4,301. (This roughly accords with the figure from the Australian Bureau of Transport and Road Economics (2000), which after allowing for inflation and conversion to Canadian dollars, equates to $3,541.) The bring forward of funeral costs associated with premature death for people with VL is estimated at around $1.1 million in 2007. 4.2 DWL FROM TRANSFERS Lost taxation revenue is considered a transfer payment, rather than an economic cost. However, raising additional taxation revenue does impose real efficiency costs on the Canadian economy, known as DWLs. Besides the cost of administering the taxation system costs, DWLs arise from the distortionary impact of taxes on workers’ work and consumption choices. 4.2.1 LOST TAXATION REVENUE Reduced earnings due to reduced workforce participation, absenteeism and premature death will also have an effect on taxation revenue collected by Canadian Governments. As well as forgone income (personal) taxation, there will also be a fall in indirect (consumption) tax, as those with lower incomes spend less on the consumption of goods and services. 72 The cost of vision loss in Canada Personal income tax forgone is a product of the average personal income tax rate and the forgone income. With VL and lower income, there will be less consumption of goods and services, estimated up to the level of the disability pension. Without VL, it is assumed that consumption would comprise (on average) virtually all household income - based on Statistics Canada reports that Canadians only save 3% of their income (Chawla and Wannell, 2005). The indirect tax forgone is estimated as a product of the forgone consumption and the average indirect tax rate. The (Federal) Canadian Goods and Services Tax (GST) rate is 5%, however most Provinces also levy separate sales taxes. In fact in Canada there are three types of sales taxes: provincial sales taxes or PST, the federal Goods and Services Tax or GST, and the Harmonized Sales Tax or HST. Every province except Alberta implements a Provincial Sales Tax or HST. The Yukon Territory, Northwest Territories and Nunavut do not have any type of regional sales tax. The HST is used in certain provinces to combine the federal GST and the PST into a single, blended, sales tax. Currently, there is a 13% HST in the provinces of New Brunswick, Newfoundland, and Nova Scotia. The HST is collected by the Canada Revenue Agency, which then remits the appropriate amounts to the participating provinces. Separate PST are collected in the provinces of British Columbia, Saskatchewan, Manitoba, Ontario, Quebec, and Prince Edward Island. Goods to which the tax is applied vary by province, as do the rates. Moreover, for those provinces whose provincial sales tax is applied to the combined cost and GST, provincial revenues decline or increase with respective changes in the GST. TABLE 4–3: PROVINCIAL SALES TAXES Province Alberta British Columbia Saskatchewan Manitoba Ontario Quebec Prince Edward Island Rate 0 7% 5% 7% 8% 7.5% 10% Notes Alcohol 10% Alcohol 10% Lodging 5% Alcohol and entertainment at restaurants 10% Alcohol at retail stores 12% Also applied to Federal GST, so effectively 7.875% Also applied to Federal GST, so effectively 10.5% Source: www.taxtips.ca From these sources it is possible to estimate taxation revenue forgone due to VL. Both Federal and Provincial direct taxes have progressive rates. For a Canadian on the average income of $40,082, total Federal income tax would be $6,166 at an average rate of 15.4%. Given the multiplicity of Provincial direct taxes, Quebec was chosen as being representative as it has one of the largest populations and its tax rates are roughly mid range. A Quebecois on an income of $40,082 would pay $2,551 in direct taxes at an average tax rate of 6.4%. These average taxation rates are sourced from the Canadian Revenue Authority. For indirect taxes, although Federal GST is 5%, the numerous Provincial indirect taxes (Table 4–3) mean that, again, Quebec is selected as a representative Province, with its effective indirect tax of 7.875%. Personal income tax forgone is then calculated as the product of the average personal income tax rate (21.8%) and the forgone income. With VL and lower income, there will be less consumption of goods and services, with the indirect taxation rate estimated as 12.9%. 73 The cost of vision loss in Canada Around $1.75 billion in lost potential tax revenue is estimated to be incurred in 2007, due to the reduced productivity of people with VL. Lost taxation revenue is considered a transfer payment, rather than an economic cost per se. 4.2.2 SOCIAL SECURITY PAYMENTS The CNIB (2005) study on the needs of blind or visually impaired people briefly covered their sources of income. The CNIB study encompassed 352 adult client participants nation-wide with VL. Of these, 61% were female (213), and 39% were male (139), while 57% of adult participants were working age (21–64), and 43% were seniors (65+). The most frequent source of income for all adult client participants was some form of government income supplement program (federal or provincial). However, unsurprisingly there were age related differences in the programs that were providing benefits. The vast majority of senior participants reported receiving a federal pension (91%), compared to only 26% of working age participants. Conversely, 41% of working age participants reported receiving provincial disability benefits, compared to only 6% of seniors. Income from employment was low overall (12% for all adult consumer participants), and again age made a difference. Of working age participants 24% reported income from employment or self-employment, compared to 2% of seniors. Seniors were more likely to report receiving a private pension (31%) than were working age participants (8%). Table 4–4 provides an overview of income sources for adult participants. TABLE 4–4: INCOME SOURCES (CNIB) Income Source All Working Age Seniors Federal pension* 54% 26% 91% Provincial disability benefits Private pension Private income Employment Spousal support 26% 18% 13% 12% 8% 41% 8% 8% 19% 9.5% 6% 31% 19% 1% 5% Self-employment Family support Other 4% 2.3% 8% 5.4% 3% 8% 1.3% 1.3% 8% * Federal pensions included Old Age Pension, Disability Pension, and Veterans Pension. Source: CNIB (2005). Publicly available data exist for social security spending and recipients in Canada – reported by Human Resources and Social Development Canada as part of its Social Security Statistics Canada and Provinces 1978-79 to 2002-03.31 Selected payments that people with VL may access are presented in Table 4–5 – these data refer to aggregate payments to all recipients rather than payments to people with VL only. 31 See: http://www.hrsdc.gc.ca/en/cs/sp/sdc/socpol/tables/page02.shtml (accessed Wednesday 6 February, 2008). 74 The cost of vision loss in Canada TABLE 4–5: VL-RELATED SOCIAL SECURITY PAYMENTS AND BENEFICIARIES Total payments ($000) Old age security Veterans' and civilians' disability pensions Canada and Quebec pension plans Employment assistance for persons with disabilities Provincial welfare programs Total Beneficiaries (number) $/beneficiary 20,464,192 1,473,118 3,330,019 378,318 20,552,751 3,941,039 164,805 340,116 5,193 8,939 9,791 46,198,398 Source: Human Resources and Social Development Canada, Social Security Statistics Canada and Provinces 1978-79 to 2002-03. The data from Table 4–5 can be used to calculate the excess number of people with VL who receive payment relative to population norms. These excess usage rates can then be multiplied by the average payment rates to estimate the social security payments for people with VL. CNIB (2005) did not include unemployment benefits as a source of income for the visually impaired. Presumably then, working age people with VL are either employed or on disability pension. TABLE 4–6: EXCESS USAGE OF SOCIAL SECURITY PAYMENTS Income Source Working Age Federal pension* Provincial disability benefits 26% 41% 4.2.3 Usage % of total population 2% 8% Excess usage 24.4% 32.8% VL working age pop 209,122 209,122 VL who get benefit 54,372 85,740 Pop who get benefit 504,921 2,577,363 % Attributable to VL 10.8% 3.3% DEADWEIGHT LOSSES The welfare payments calculated immediately above are, like taxation revenue losses, not themselves economic costs but rather a financial transfer from taxpayers to the income support recipients. The real resource cost of these transfer payments is only the associated DWL. DWLs refer to the costs of administering welfare pensions and raising additional taxation revenues. For any given fiscal position, invalid and sickness benefits must be financed through taxation. Although welfare payments and forgone taxation are not real costs (so should not be included in the estimation of total costs), it is still worthwhile estimating them as that helps us understand how the total costs of VL are shared between the taxpayer, the individual and other financiers. DWL is the loss of consumer and producer surplus, as a result of the imposition of a distortion to the equilibrium (society preferred) level of output and prices. Taxes alter the price and quantity of goods sold compared to what they would be if the market were not distorted, and thus lead to some diminution in the value of trade between buyers and sellers that would otherwise be enjoyed (Figure 4-1). 75 The cost of vision loss in Canada FIGURE 4-1: DWL OF TAXATION Price ($) Supply Deadweight Loss (cost of raising taxation revenue) Price plus Tax Taxation Revenue Price Demand Output Actual Quantity Supplied Potential Quantity Supplied Usher (2002) estimates the DWL of raising revenue in Canada at 20.2%. Access Economics estimates that around $1.75 billion in DWL is incurred in 2007, due to the additional taxation required to replace that forgone due to lost productivity of people with VL and welfare payments. Of this, $1.2 billion is a result of the governmentfinanced component of health system expenditures, $348 million is due to taxation revenue forgone and $185 million is due to welfare expenditures. 4.3 CARE AND OTHER ASSISTANCE Carers are people who provide informal care to others in need of assistance or support. Most informal carers are family or friends of the person receiving care. Carers may take time off work to accompany people with VL to medical appointments, stay with them in hospital, or care for them at home. Carers may also take time off work to undertake many of the unpaid tasks that the person with VL would do if they did not have VL and were able to do these tasks. A recent study focusing on AMD only rather than overall VL calculated the burden of neovascular AMD in the Canadian population (Cruess et al, 2007). This cross-sectional, observational analysis was conducted in relation to self-reported functional health, wellbeing and disease burden among elderly subjects in Canada with (n=67) and without (n=99) neovascular AMD. 32 Subjects with neovascular AMD reported significantly worse vision-related functioning and overall wellbeing than controls (adjusted mean scores on the NEI-VFQ-2532: 48.0 vs. 87.5) and significantly more depression symptoms than controls (Hospital Anxiety and Depression Scale: 5.8 vs. 4.3). The annual neovascular AMD cost per patient was $11,334, which is over eight National Eye Institute Visual Functioning Questionnaire http://www.nei.nih.gov/resources/visionfunction/vfq_ia.pdf 76 (25 questions). See, for example, The cost of vision loss in Canada times that of elderly subjects without neovascular AMD ($1,412). Over half of the neovascular AMD costs were direct medical costs. Subjects with neovascular AMD also reported more than twice the need for assistance with daily activities compared with controls (19% vs. 9%). This allows us to calculate the excess care required by people with AMD relative to the rest of the population – by taking the difference between the two figures. FIGURE 4-2: COMPARISON OF ASSISTANCE WITH ACTIVITIES OF DAILY LIVING BETWEEN STUDY GROUPS 19% Neovascular AMD Control group 13% 9% 4% Daily activities Home care overall 5% 3% 2% 3% 4% 4% 5% 2% 1% Other Administrative transportation tasks 0% Self care Transportation for health care Leisure activities Source: Cruess et al (2007). Cruess et al (2007) also reported unit costs for non-medical related costs of AMD with data sourced from the Canadian Management Information Systems database. These data relate to people with AMD only rather than people with VL as a whole. The main unit cost categories were direct vision-related medical costs, direct non vision-related medical costs, and direct non-medical costs (living in government-sponsored assisted living facilities, assistance received for daily activities, and social benefits received). Given that other health-related costs data sources have already been identified in this study (see Sections 3 and 4), the most useful data from Cruess et al (2007) related to the non-medical costs. After collecting the unit costs, annual utilisation costs were then calculated by multiplying the number of units consumed by the unit cost. Overall, people with AMD had much higher non-medical costs ($2,553.25) which included home care/living assistance compared to the control group ($601.02). TABLE 4–7: ANNUAL DIRECT AMD NON-MEDICAL RELATED UTILISATION COSTS PER PERSON (2005$) Direct non medical related utilisation costs per person AMD Total living situation related costs $240.68 Control $0.00 Total costs of assistance for daily activities received $2,312.57 $601.02 Total $2,553.25 $601.02 Source: Cruess et al (2007). 77 The cost of vision loss in Canada Cruess (2007) provides an overview of carer costs for AMD ($2,553.25 per person per annum) and for an age-matched control group ($601.02). Thus, the difference between the two groups ($1,952.23 pa) is the cost of care that is specific to AMD. Access Economics has assumed that additional care is not due to having a particular eye disease as such, so much as to the VL caused by that disease. AMD’s disability weight (0.235) is 1.6 times higher than the average disability weight across all eye diseases (0.145). So, factoring down, the expected care costs for people with VL – above their fully sighted counterparts – would be $1,208.99 per person per year. Thus, for the total visually impaired population of 0.82 million, annual carer costs attributable to VL is $0.63 billion. Rehabilitation and library costs According to CNIB, the cost of provision of rehabilitation services for people with vision loss in 2007 was $32.8 million. In addition, the cost of special library services for people with vision loss was $7.4 million. Only 23% of these funds are provided by government. The rest is provided by support from the public. Also, there are two other significant organizations providing services in Quebec – the Institut Nazareth et Louis Braille and MAB-Mackay (the Montreal Association for the Blind and the Mackay Rehabilitation Centre). Financial information from most recent annual reports on their websites33 suggests costs relating to these organisations are estimated as $12.8 million and $8.8 million respectively in 2007. In total, the rehabilitation and library costs are estimated as $61.8 million and total cost of care is estimated as $0.693 billion. 4.4 AIDS AND DEVICES People who are visually impaired or blind require a variety of devices, special equipment and home modifications to function adequately and to enhance their quality of life. The greater need for devices and home modifications due to VL and blindness has been established in international studies (for example, Brezin, 2005; Access Economics, 2004a). In the Australian study, the cost of devices and modifications was estimated as A$318 to A$571 per visually impaired person on average in 2004. The French study estimated only additional utilization, not costs. Two sets of supports are provided for people with low vision and those who are blind because of the different needs of these two populations. For people who are blind, support primarily involves assistance using non-visual sensory data. For those with low vision, supports primarily involve magnifying or enlarging, brightening and enhancing contrast in visual displays or cues. CNIB is the primary source for devices for the visually impaired and, as a result, prices reported are from CNIB price lists for the period 2000-01, weighted by the number of items sold of each of the brands/models available. Volumes of sales were reported in the December 2003 Price Survey of Assistive Devices and Supports for Persons with Disabilities produced by the Department of Human Resources and Social Development. 33 http://www.mab.ca/ and http://www.inlb.qc.ca/apropos/ra2006-2007.aspx#s11 78 The cost of vision loss in Canada 4.4.1 These data are inflated to 2007 by Consumer Price Inflation and population growth. They provide a good indication of the types of aids and modifications used, as well as the volume in which they are used across Canada and their price. CANES AND ACCESSORIES Two different brands/types of canes were priced—a mobility (way-finding) cane and a support cane. Each is available in three identically priced models. In 2000, 1,278 canes were sold at an average price of $21.78. The mobility cane folds, comes with a rubber tip grip bottom, handle and connecting elastics. The average price for the 626 mobility canes sold was $20.00. The support cane is made of moulded plastic, has a height adjustment and a rubber tip grip bottom. A total of 652 of these were purchased at an average price of $23.50. These types of cane can also be used by some people with mobility limitations. In addition, three frequently purchased accessories were priced. Replacement cane elastics for the folding mobility canes—163 were purchased at a price of $0.30 each. Roller tips used for some types of mobility canes (the cane slides on a ball bearing allowing continuous contact with the ground, providing an alternative method for way finding—a sweeping motion rather than the more common tapping motion)—163 of these were purchased at $11.00 each. Flip-up ice spikes which replace grip bottoms on support canes—166 were purchased at a price of $8.80 each. TABLE 4–8: CANES/ACCESSORIES FOR THE BLIND (2000-01$) Product Canes Way Finding Canes Support Canes Accessories For Way finding Canes: Replacement cane plastics Roller Tips For Support Canes: Ice Spikes (flip-up) Sub total Number sold per year Average price Cost per year (in 2000-01) 1,278 626 652 $21.78 $20.00 $23.50 $27,834.84 $12,520.00 $15,322.00 163 163 $0.30 $11.00 $48.90 $1,793.00 166 $8.80 $1,460.80 1,770 n/a $31,144.70 Note: Numbers may not sum exactly due to rounding. 4.4.2 WRITING AIDS/STATIONERY Writing and reading for the blind primarily uses the Braille system of embossed dot patterns. Braille embossers are devices designed to produce Braille writing on paper. They can be as simple as slates/frames and stylus or manual, Braille typewriters such as the Perkins Brailler. However, there are also more advanced computerized brailing devices such as the Mountbatten Brailler. There are also high speed computer Braille printers. 79 The cost of vision loss in Canada 4.4.2.1 BRAILLE SLATES/FRAMES AND STYLUSES Braille slates/frames and stylus systems are used to manually emboss Braille dots. Braille slates are part of a frame such that a two-line slate can be stepped down a page with a hinge system to give a whole page of Braille. Plastic slates are lighter than metal ones but tend to have a lower life expectancy. Frames without hinges only work with a fixed size of paper, but are very popular as a highly portable note-taking device. The stylus handle design significantly affects ease of use. The easier to use, large handle styluses, however, are less convenient to carry. The weighted average price of the 16 slates commonly purchased at CNIB is $56.61. A total of 790 basic four-line plastic slates were sold at $6.50. However, this was the minimum price slate – and prices varied to a maximum of $158.50 for a 28-line, full page, heavy duty metal slate. The average price of the six CNIB styluses available at CNIB is $6.00. The ‘Erasable’ stylus is priced at $21.50. 4.4.2.2 BRAILLE TYPEWRITERS The average price of the five manual Perkins Braillers sold at CNIB is $1,393.20. The electric Perkins Brailler is priced at $1,750. 4.4.2.3 NOTE TAKERS Note takers are computerized devices which have either standard or Braille-input keyboards. They usually have built-in speech output and/or Braille displays. They may be either palmtop or laptop devices. Standard-key note takers are used by persons with vision impairment, Braille note takers by persons who are blind. Common features that come with note takers include word processing, diary, telephone directory, database and communications functions, and plugs which allow the user to connect peripheral devices such as printers, modems and Braille embossers. The note taker available at CNIB provides a Braille-input keyboard and Braille display/computer output at a price of $5,365. 4.4.2.4 COMMON STATIONERY Three types of Braille paper were priced. Each is rawhide tag manila and regular weight, and contains approximately 250 sheets per package. The average price paid for 1,094 purchases of the best selling Braille paper was $24.34. In addition, CNIB sells a number of Braille calendars. In 2000-01, 532 were sold at a price of $2.00. 80 The cost of vision loss in Canada TABLE 4–9: WRITING AND STATIONERY ITEMS (2000-01$) Product Number sold Average per year price Braille Paper (250 sheet package) 1,094 Cost per year (in 2000-01) $24.34 $26,627.96 8.5 x 11 inches 560 $14.25 $7,980.00 11 x 11 inches 322 $17.75 $5,715.50 Computer paper, 12.5 x 11 Cerlox 212 $61.00 $12,932.00 Embossing Sheets 1,319 $3.00 $3,957.00 532 $2.00 $1,064.00 Braille Calendar Total 2,945 n/a $36,783.50 Note: Numbers may not sum exactly due to rounding. 4.4.3 VARIABLE SPEED TAPE RECORDERS A total of 12 cassette recorders were available from CNIB at an average price of $263.33. Prices varied from a minimum of $62.50 for a portable to $528.50 for a large, desk-top model. Most prices were near or at the overall average. 4.4.4 COMPUTER VOICE SYNTHESIZER SOFTWARE Five types of common computer software used by people who are blind are available from CNIB. Three of these convert data from either a file or a screen display to voice. The average price of this software was $1,328.33. Two also included scanning capacity and convert written documents to computer files, as well as providing a voice synthesizer. The average price of these two packages was $1,795. These software packages can also be used with electronic Braille display systems (see next sub-section). 4.4.5 ELECTRONIC BRAILLE DISPLAY SYSTEMS An electronic Braille display system is a device designed to present computer screen text as Braille. A Braille display uses a series of electronic ‘pins’, which are either in the up or down position. Text on the screen is displayed as Braille through the pattern of up and down pins. Braille displays make excellent computer access devices for Braille-literate persons but are very expensive. The model available at CNIB is priced at $18,708. 4.4.6 TALKING TIME PIECES Three types of time pieces were priced—talking clocks, wrist watches and a talking key chain. All prices include batteries. A total of 1,406 talking clocks were purchased in 2000 at an average price of $20.65. The cost of the four different devices ranged from a low of $14.95 to a high of $28.50. In 2000, a total of 4,650 talking wrist watches were purchased, at an average price of $19.24. Four different brands were commonly sold, varying from a price of $9.00 to a high of $65.00. Price varies considerably with watch style and features. For example, the more expensive watches have a gold or silver casing and choice of alarm sounds, while the lower range watches are encased in plastic. 81 The cost of vision loss in Canada Talking time-keeping key chains cost an average of $11.00 and in 2000, 1,652 were sold. TABLE 4–10: TALKING TIME PIECES (2000-01$) Product Number sold Average Cost per year per year price (in 2000-01) Talking clocks 1,278 $21.78 $27,834.84 Talking wrist watches 4,650 $19.24 $89,466.00 Talking key chain 1,652 $11.00 $18,172.00 Total 7,580 n/a $135,472.84 Note: Numbers may not sum exactly due to rounding. 4.4.7 SUNGLASSES WITH NON-CORRECTIVE LENSES A total of 4,570 regular sunglasses were sold by CNIB in 2000 at an average price of $12.35. Sunglasses with UV protection were most popular. A total of 3,544 pairs were sold in 2000 at an average price of $13.00. The remaining 631 pairs of regular sunglasses were sold at $8.00. TABLE 4–11: SUNGLASSES WITH NON-CORRECTIVE LENSES (2000-01$) Product 4.4.8 Number sold Average per year price Cost per year (in 2000-01) Sunglasses with UV protection Regular sunglasses 3,544 631 $13.00 $8.00 $46,072.00 $5,048.00 Total 4,175 n/a $51,120.00 HAND HELD MAGNIFIERS Magnifiers vary in strength and can come with small lights or ‘illuminators’. The average price of the 4,531 magnifiers sold in the year 2000 by CNIB was $33.70. At one end of the spectrum in this group are simply-designed, light, plastic magnifiers, which are priced in the $9.50-$14.50 range. At the other end are more solidly built models with glass lenses and/or illuminators, which are priced in the $43.50 to $50.00 range. Magnifying sheets were also priced. These are plastic covers that fit over and magnify book or newspaper pages. A total of 2,180 sheets were sold in 2000 at a price of $2.20. TABLE 4–12: HAND HELD MAGNIFIERS (2000-01$) Product 4.4.9 Number sold Average Cost per year (in 2000-01) per year price Magnifiers/hand readers 4,521 $33.70 $152,357.70 Total 4,521 n/a $152,357.70 VIDEO MAGNIFIERS/CCTVS Screen magnifiers enlarge what is displayed on a computer monitor so people with vision problems can read the text on the screen. Closed Circuit Televisions (CCTVs) are devices that use a camera 82 The cost of vision loss in Canada to magnify printed text and images placed under it. These are then presented enlarged on a television screen or computer monitor. CNIB has two electronic video magnifiers that connect to an ordinary TV. The black and white only magnifier is priced at $1,119, while the colour model costs $1,499. CNIB also has a number of full CCTV systems, which include the monitor and TV screen and which can be connected to a computer. The average price of the black and white CCTVs offered is $2,875 and the colour CCTVs have an average price of $4,348. 4.4.10 SCREEN MAGNIFICATION SOFTWARE Screen magnification software significantly enlarges screen text and graphics to a size that a vision impaired users can easily view. CNIB offers two such products at an average price of $814.50 4.4.11 OTHER AIDS FOR THE SIGHT IMPAIRED 4.4.11.1 STATIONERY Three different writing pads with bolded lines were priced. These pads include 100 white sheets of black thick lined writing paper. In total, 1,200 pads were purchased in 2000, each at $3.80. In addition, 10,829 large print calendars were purchased at a price of $2.00. TABLE 4–13: OTHER STATIONERY (2000-01$) Product Writing pads 4.4.11.2 Number sold Average Cost per year per year price (in 2000-01) 1,200 $3.80 $4,560.00 Large print calendars 10,829 $2.00 $21,658.00 Total 12,029 n/a $26,218.00 LARGE BUTTON TELEPHONES Two prices for large button telephones with high sales volumes were obtained from CNIB price list. The first model phone also has speaker phone capacity. A total of 244 of these phones were sold in 2000 at a price of $33.00. The second phone provides features for persons who are also hearing impaired—a hearing aid attachment and an adjustable very loud ringer. In 2000, 226 of these were sold at $70.00. 83 The cost of vision loss in Canada TABLE 4–14: LARGE BUTTON TELEPHONES (2000-01$) Product 4.4.12 Number sold Average Cost per year per year price (in 2000-01) Phone with speaker phone capacity 244 $33.00 $8,052.00 Phone for hearing impaired 226 $70.00 $15,820.00 Total 470 n/a $23,872.00 SUMMARY OF AIDS AND DEVICES Overall, available CNIB data on prices and volumes show that there was around $456,968.74 spent on vision impairment-related aids and devices (Table 4–15) in 2000-01. In today’s dollars that would equate to around $524,046.72 (after inflating by the Consumer Price Index). 84 The cost of vision loss in Canada TABLE 4–15: SUMMARY OF AIDS AND DEVICES (2000-01$) Number sold per year Average price Cost per year (in 2000-01) 1,278 626 $21.78 $20.00 $27,834.84 $12,520.00 Support Canes 652 $23.50 $15,322.00 Accessories for Way Finding Canes Replacement cane plastics Roller Tips 163 163 $0.30 $11.00 $48.90 $1,793.00 Accessories for Support Canes Ice Spikes (flip-up) 166 $8.80 $1,460.80 1,770 n/a $31,144.70 790 $6.50 $5,135.00 1,094 560 322 $24.34 $14.25 $17.75 $26,627.96 $7,980.00 $5,715.50 Embossing Sheets Braille Calendar 212 1,319 532 $61.00 $3.00 $2.00 $12,932.00 $3,957.00 $1,064.00 Sub total 2,945 n/a $36,783.50 Talking clocks 1,278 $21.78 Talking Wrist Watches 4,650 $19.24 Talking Key Chain 1,652 $11.00 $27,834.84 $89,466.00 $18,172.00 Sub total 7,580 n/a $135,472.84 Product Canes Way Finding Canes Sub total Braille slates Braille Paper (250 sheet package) 8.5 x 11 inches 11 x 11 inches Computer paper, 12.5 x 11 Cerlox Magnifiers/Hand Readers 4,521 $33.70 3.5-4.4X magnifier 1,514 $32.52 5X–11X magnifier w/light 1,076 $43.50 $152,357.70 $49,235.28 $46,806.00 Sub total 4,521 n/a $152,357.70 Sunglasses with UV protection Regular sunglasses 3,544 631 $13.00 $8.00 $46,072.00 $5,048.00 Sub total 4,175 n/a $51,120.00 Writing pads Large print calendars 1,200 10,829 $3.80 $2.00 $4,560.00 $21,658.00 Sub total 12,029 n/a $26,218.00 Phone with speaker phone capacity Phone for hearing impaired 244 226 $33.00 $70.00 $8,052.00 $15,820.00 Sub total 470 n/a $23,872.00 Total $456,968.74 The above data are supplemented by estimates of volumes data on: Braille slates/frames and styluses; Braille typewriters; note takers; variable speed tape recorders; computer voice synthesiser 85 The cost of vision loss in Canada software; electronic Braille display systems; video magnifiers/CCTVs; and screen magnification software. Volume data were estimated by using US usage per person data from Access Economics (2006). These additional devices added $15.1 million for CNIB clients, resulting in an overall total for CNIB aids and modifications of $15.6 million. TABLE 4–16: ESTIMATES OF ADDITIONAL AIDS AND DEVICES Product Number sold per year Average price Cost per year (in 2000-01) Stylus Erasable stylus Braille typewriter Note takers Variable speed tape recorders 835 835 835 835 835 6 21.5 1750 5365 263.33 $5,012 $17,959 $1,461,742 $4,481,282 $219,955 Computer voice synthesisers Electronic Braille display systems Video magnifiers (black and white) 281 1328.33 $372,977 281 18708 $5,252,954 281 1119 $314,200 CCTVs (black and white) 281 2875 $807,261 Screen magnification software 281 814.5 $228,701 Total $13,162,042 Total (inflated to 2007$) $15,094,084 Using an active CNIB client base of 42,000 people this translates to $371.86 per person with VL. Multiplying this by the number of people with VL gives us a total cost of aids and modifications of $303.9 million. This cost has been allocated equally between individuals, family and friends, government, employment and society / other (health insurance entities). 4.5 SUMMARY OF OTHER FINANCIAL COSTS In total, the non-health related financial costs of VL are estimated to be around $7.1 billion in 2007. TABLE 4–17: SUMMARY OF OTHER FINANCIAL COSTS OF VL, 2007 $ million Productivity costs Carer costs Aids and modifications, funerals DWL Total other financial costs 86 4431 693 305 ,1,757 7,186 The cost of vision loss in Canada 5. BURDEN OF DISEASE The main cost of VL is the loss of wellbeing and quality of life that it entails. Access Economics adopts ‘burden of disease’ methodology in order to quantify this substantial cost component. This methodology was developed by the World Health Organization, the World Bank and Harvard University to comprehensively measure mortality and disability from diseases, injuries and risk factors in 1990, projected to 2020 (Murray and Lopez, 1996). The approach is non-financial, where pain, suffering and premature mortality are measured in terms of Disability Adjusted Life Years (DALYs), with 0 representing a year of perfect health and 1 representing death (the converse of a QALY or ‘quality-adjusted life year’ where 1 represents perfect health). The DALY approach has been successful in avoiding the subjectivity of individual valuation and is capable of overcoming the problem of comparability between individuals and between nations. This report treats the value of a life year as equal throughout the lifespan. 5.1 WILLINGNESS TO PAY AND THE VALUE OF A LIFE YEAR 5.1.1 MEASURING BURDEN: DALYS, YLLS AND YLDS In the last decade a non-financial approach to valuing human life has been derived, where loss of wellbeing and premature mortality – called the ‘burden of disease and injury’ – are measured in terms of Disability Adjusted Life Years, or DALYs. This approach was developed by the World Health Organization (WHO), the World Bank and Harvard University for a study that provided a comprehensive assessment of mortality and disability from diseases, injuries and risk factors in 1990, projected to 2020 (Murray and Lopez, 1996). Methods and data sources are detailed further in Murray et al (2001) and the WHO continues to revisit the estimates for later years. A DALY of 0 represents a year of perfect health, while a DALY of 1 represents death. Other health states are attributed values between 0 and 1 as assessed by experts on the basis of literature and other evidence of the quality of life in relative health states. For example, the disability weight of 0.18 for a broken wrist can be interpreted as losing 18% of a person’s quality of life relative to perfect health, because of the inflicted injury. Total DALYs lost from a condition are the sum of the mortality and morbidity components – the Year(s) of Life Lost due to premature death (YLLs) and the Year(s) of healthy life Lost due to Disability (YLDs). The DALY approach has been successful in avoiding the subjectivity of individual valuation and is capable of overcoming the problem of comparability between individuals and between nations, although some nations have subsequently adopted variations in weighting systems, for example age-weighting for older people. This report treats the value of a life year as equal throughout the lifespan. As these approaches are not financial, they are not directly comparable with most other cost and benefit measures. In public policy making, it is often desirable to apply a monetary conversion to ascertain the cost of an injury, disease or fatality or the value of a preventive health intervention, for example, in cost benefit analysis. Such financial conversions tend to utilise ‘willingness to pay’ or risk-based labour market studies as described in the next section. 5.1.2 WILLINGNESS TO PAY AND THE VALUE OF A STATISTICAL LIFE YEAR The burden of disease as measured in DALYs can be converted into a dollar figure using an estimate of the Value of a ‘Statistical’ Life (VSL). As the name suggests, the VSL is an estimate of the value society places on an anonymous life. Since Schelling’s (1968) discussion of the 87 The cost of vision loss in Canada economics of life saving, the economic literature has focused on willingness to pay (WTP) – or, conversely, willingness to accept (WTA) – measures of mortality and morbidity, in order to develop estimates of the VSL. Estimates may be derived from observing people’s choices in situations where they rank or trade off various states of wellbeing (loss or gain) either against each other or for dollar amounts eg, stated choice models of people’s WTP for interventions that enhance health or WTA poorer health outcomes or the risk of such states. Alternatively, risk studies use evidence of market trade-offs between risk and money, including numerous labour market and other studies (such as installing smoke detectors, wearing seatbelts or bike helmets and so on). The extensive literature in this field mostly uses econometric analysis to value mortality risk and the ‘hedonic wage’ by estimating compensating differentials for on-the-job risk exposure in labour markets; in other words, determining what dollar amount would be accepted by an individual to induce him/her to increase the probability of death or morbidity by a particular percentage. Viscusi and Aldy (2002), in a summary of mortality studies, find the VSL ranges between US$4 million and US$9 million with a median of US$7 million (in year 2000 US dollars), similar but marginally higher than the VSL derived from studies of US product and housing markets. They also review a parallel literature on the implicit value of the risk of non-fatal injuries. Weaknesses in the WTP approach, as with human capital approaches to valuing life and wellbeing, are that there can be substantial variation between individuals. Extraneous influences in labour markets such as imperfect information, income/wealth or power asymmetries can cause difficulty in correctly perceiving the risk or in negotiating an acceptably higher wage in wage-risk trade off studies, for example. As DALYs are enumerated in years of life rather than in whole lives it is necessary to calculate the Value of a ‘Statistical’ Life Year (VSLY) based on the VSL. This is done using the formula:34 VSLY = VSL / Σi=0,…,n-1(1+r)i Where: n = years of remaining life, and r = discount rate. Clearly there is a need to know n (the years of remaining life), and to determine an appropriate value for r (the discount rate). There is a substantial body of literature, which often provides conflicting advice, on the appropriate mechanism by which costs should be discounted over time, properly taking into account risks, inflation, positive time preference and expected productivity gains. In reviewing the literature, Access Economics (2008) found the most common rate used to discount healthy life was 3%, perhaps the most eminent sources being Nordhaus, 2002 (Yale); Murphy and Topel, 2005 (University of Chicago); Cutler and Richardson, 1998 (Harvard); WHO, 2002; Aldy and Viscusi, 2006). This report assumes a discount rate for future streams of health in Canada of 3%. Further it is assumed that on average people have 40 years of life remaining.35 34 The formula is derived from the definition: i VSL = ΣVSLYi/(1+r)^ where i=0,1,2….n where VSLY is assumed to be constant (i.e. no variation with age). 35 This assumption relates to the average years of life remaining for people included in VSL studies, not the years of life remaining for people with VL. 88 The cost of vision loss in Canada Access Economics (2008a) identified 16 Canadian VSL studies (Table 5–1). Converting the study findings into 2007 Canadian dollars, the average of VSL estimates was $4.66 million36. A discount rate of 3% was applied to calculate the 2007 Canadian VSLY at $195,837. TABLE 5–1: VALUE OF A STATISTICAL LIFE IN CANADIAN STUDIES ($ MILLION) Authors Year Currency Study Area Belhadji Meng and Smith Transport Canada Krupnick et al. 1994 CAD 1990 USD Transport Occupational Risk 1996 USD Transport 2000 CAD Viscusi Alberini et al. Alberini et al. Meng and Smith Hara Associates Miller Martinello and Meng Dionne and Lanoie 2005 USD 2002 USD 2002 USD 1999 USD Health Occupational Risk Occupational Risk Occupational Risk Occupational Risk 2000 2000 USD USD 1992 USD 2002 CAD Meng Vodden et al. Cousineau et al. Bellavance et al. Average 1989 USD 1994 CAD 1991 USD Mixed Occupational Risk Occupational Risk Occupational Risk 2007 USD Mixed Health Mixed Occupational Risk Lowest estimate Highest estimate 0.4 3.2 Single/ average estimate VSL in 2007 $CAN 1.2 1.6 1.2 2.1 1.8 2.7 2.5 2.9 3.9 4.7 2.4 3.0 0.5 0.9 2.4 3.3 1.3 3.7 2.4 3.3 2.4 3.4 2.4 2.5 3.5 3.6 3.1 5.1 4.7 5.3 4.0 7.6 6.1 7.9 4.8 8.0 9.2 11.2 4.7 1.7 2.1 5.2 BURDEN OF DISEASE FROM VISION LOSS 5.2.1 DISABILITY WEIGHTS 5.7 3.1 Disability weights for mild, moderate and severe VL are based on the Dutch weights from the global burden of disease study (Murray and Lopez, 1996). These are: 36 Figures converted to $2007 Canadian using OECD Purchasing Power Parity rates. One additional study (Lanoie et al, 1995) was rejected as an outlier beyond reasonable parameters, given its VSL estimate was $37.5 million. 89 The cost of vision loss in Canada 0.020 for mild VL; 0.170 for moderate impairment; and 0.430 for severe impairment (blindness). Section 1.2 presents the distribution of severity for each of the major eye diseases. To derive a total for Canada, these individual disease distributions were weighted by their overall prevalence. This yields an average disability weighting for Canadian VL of 0.093. The burden of disease is thus calculated on a prevalence basis from the prevalence estimates from Section 2.4, together with disability weights, for the year 2007. DEATHS FROM VL 5.2.2 The Australian Institute of Health and Welfare (Begg et al, 2007) estimates that in Australia in 2003, the visually impaired population numbered 510,761, and that the number of deaths due to that VL was 163. Given the number of visually impaired persons in Canada in 2007 is 817,171 on a pro-rata basis, the expected number of deaths caused by VL was 261. YEARS OF LIFE LOST DUE TO DISABILITY 5.2.3 Based on the disability weight outlined above and the total number of people experiencing VL, the YLD for VL has been calculated by gender (Table 5–2), for the year 2007. In total, YLD for VL was an estimated 75,891 DALYs in 2007. TABLE 5–2: ESTIMATED YEARS OF HEALTHY LIFE LOST DUE TO DISABILITY (YLD), 2007 (DALYS) Estimated disability weight Prevalence YLD 0.093 0.093 340,097 476,854 31,572 44,268 Males Females YEARS OF LIFE LOST DUE TO PREMATURE DEATH. 5.2.4 Based on the relative risk of mortality due to VL outlined above, it is estimated that there are around 261 deaths per year due to VL. YLL were estimated from the age-gender distribution of deaths by the corresponding YLL for the age of death in the Standard Life Expectancy Table (West Level 26) with a discount rate of 3% and no age weighting. In total, YLL for VL was an estimated 1,467 DALYs in 2007. TABLE 5–3: YEARS OF LIFE LOST DUE TO PREMATURE DEATH (YLL) DUE TO VL, 2007 15-29 Males Females Persons 90 30-39 0 0 0 40-49 0 0 0 50-59 4 2 6 22 15 37 60-69 58 38 96 70-79 181 153 334 80+ 359 635 993 Total 623 844 1,467 The cost of vision loss in Canada 5.3 TOTAL DALYS DUE TO VL The overall loss of wellbeing due to VL is estimated as 77,306 DALYs. Figure 5-1 illustrates the YLD and YLL components by age and gender. The greatest impact of VL is in old age, reflecting the physiology of VL and higher YLD due to the large number of Canadians with VL in this cohort. FIGURE 5-1: LOSS OF WELLBEING DUE TO VL (DALYS), BY AGE AND GENDER, 2007 16,000 Female YLL 14,000 Male YLL Female YLD 12,000 Male YLD DALYs 10,000 8,000 6,000 4,000 2,000 90+ 85-89 80-84 75-79 70-74 65-69 60-64 55-59 50-54 45-49 40-44 35-39 30-34 25-29 20-24 15-19 10-14 5-9 0-4 0 Age Groups Multiplying the number of DALYs by the VSLY ($195,837) provides an estimate of the dollar value of the loss of wellbeing due to VL. The estimated gross cost of lost wellbeing from VL is $15.2 billion in 2007. Bearing in mind that the wage-risk studies underlying the calculation of the VSL take into account all known personal impacts – suffering and premature death, lost wages/income, out-of-pocket personal health costs and so on – the estimate of $15.2 billion should be treated as a ‘gross’ figure. However, costs specific to VL that are unlikely to have entered into the thinking of people in the source wage/risk studies should not be netted out (e.g. publicly financed health spending, care provided voluntarily). The results after netting out are presented in Table 5–4. 91 The cost of vision loss in Canada TABLE 5–4: NET COST OF LOST WELLBEING, $MILLION, 2007 Gross cost of wellbeing Less health costs borne out-of-pocket Less individual production losses net of tax Less other indirect costs borne out-of-pocket Plus transfers to people with VL Net cost of lost wellbeing The estimated net cost of lost wellbeing from VL is $11.7 billion in 2007. 92 15,200 1,499 2,847 61 917 11,710 The cost of vision loss in Canada 6. SUMMARY In 2007, the financial cost of VL was $15.8 billion (Table 6–1). Of this: $8.6 billion (54.6%) was direct health system expenditure; $4.4 billion (28.0%) was productivity lost due to lower employment, absenteeism and premature death of Canadians with VL; $1.8 billion (11.1%) was the DWL from transfers including welfare payments and taxation forgone; $0.7 billion (4.4%) was the value of the care for people with VL; and $305 million (1.9%) was other indirect costs such as aids and home modifications and the bring-forward of funeral costs. Additionally, the value of the lost wellbeing (disability and premature death) was a further $11.7 billion. TABLE 6–1: VL, TOTAL COSTS BY TYPE OF COST AND BEARER, 2007 Individuals Family/ Friends Federal Government Provincial Governments Society/ Other Employers Total Total cost ($ million) Burden of disease Health system costs Productivity costs Carer costs Other Indirect costs Deadweight losses Transfers Total financial costs Total costs including burden of disease 11,710 1,499 2,847 0 61 0 -917 3,490 15,200 0 0 0 413 62 0 0 474 0 388 886 218 0 0 917 2,409 0 5,670 619 0 61 0 0 6,350 0 0 80 0 61 0 0 141 0 1,081 0 62 61 1,757 0 2,960 11,710.4 8,637.9 4,431.4 692.8 304.9 1,757.0 0 15,824 474 2,409 6,350 141 2,960 27,534 Cost per person with visual impairment ($) 14,334 0 0 0 0 0 14,334 Health system costs 1,835 0 475 6,941 0 1,323 10,573 Productivity costs Carer costs Other Indirect costs Deadweight losses Transfers Total financial costs Total costs including burden of disease 3,485 0 74 0 -1,122 4,272 0 505 76 0 0 581 1,084 267 0 0 1,122 2,948 757 0 74 0 0 7,773 98 0 74 0 0 172 0 76 74 2,151 0 3,624 5,424 848 373 2,151 0 19,370 18,606 581 2,948 7,773 172 3,624 33,704 Burden of disease In per capita terms, this amounts to a financial cost of $19,370 per person with VL per annum. Including the value of lost wellbeing, the cost is $33,704 per person per annum. The shares by each type of financial cost are illustrated in Figure 6-1, while the financial cost shares by bearer are shown in Figure 6-2. 93 The cost of vision loss in Canada FIGURE 6-1: FINANCIAL COSTS OF VL, BY TYPE OF COST (% TOTAL) DWL 11.1% Indirect Costs 1.9% Carer Costs 4.4% Productivity Costs 28.0% Health System Costs 54.6% Individuals with VL bear 22.1% of the financial costs, and their families and friends bear a further 3.0%. Federal government bears 15.2% of the financial costs (mainly through taxation revenues forgone and welfare payments). Provincial governments bear 40.1% of the costs, reflecting the nature of Canada’s Federal system, while employers bear 0.9% and the rest of society bears the remaining 18.7%. If the burden of disease (lost wellbeing) is included, individuals bear 55.2% of the costs and Provincial governments bear 23.1% while the Federal government bears a lesser 8.7%, with family and friends 1.7%, employers 0.5% and others in society 10.8%. FIGURE 6-2: FINANCIAL COSTS OF VL, BY BEARER (% TOTAL) Society/Other 18.7% Individuals 22.1% Employers 0.9% Family/Friends 3.0% Federal Government 15.2% Provincial Governments 40.1% 94 The cost of vision loss in Canada As well as cost information, an important finding from this analysis was the observation that, for an advanced Western nation, Canada has a serious deficiency in eye health data. CNIB’s Health Economic Statement (http://www.costofblindness.org/media/health-state.asp) observes that, with respect to blindness and vision loss, there is ‘strong argument for saying that Canada has the worst record of supporting research of all the G8 countries’. The importance of good eye health to Canadians is shown from survey data in the same document revealing that two-thirds of Canadians would cash in all their savings or sell everything they owned to save their eyesight. With a rapidly aging population, it is high time for a Canadian population eye health study to monitor incidence, prevalence and morbidity outcomes and economic impacts more robustly in the future. 95 The cost of vision loss in Canada APPENDIX A: EDPRG PREVALENCE TABLES Recognizing the need for national estimates of VL, Prevent Blindness America and the National Eye Institute invited the principal investigators of several population-based vision studies to a meeting in Fort Lauderdale, Florida, in May 2001, to standardize disease definitions and methods of data reporting so that available data from many of these studies might be analysed together. Prevalence of eye disease and associated blindness and low vision were calculated based on studies from the US, Western Europe, the West Indies and Australia. The number of individuals with each disease and the total number in the respective populations were provided in five year age increments by age, gender and ethnicity for the adult population from each of the studies. Prevalence rates were then combined using a meta-analysis technique for reducing the overall variance of the pooled rate. TABLE A-1: SOURCE STUDIES FOR EDRPG DATA Study and location Baltimore Eye Survey, US Barbados Eye Studies, West Indies Beaver Dam Eye Study, US BMES, Australia MVIP, Australia Proyecto Vision Evaluation Research, US Rotterdam Eye Study, The Netherlands Salisbury Eye Evaluation Project, US B/VL RE BW BW W W W H W BW W H W AMD Cataract DR Glaucoma BW B W W W B W W W BW W BW BW B W W W H W W W H W Note: B = Black, H = Hispanic, W = White, B/VL = Blindness / VL Source: Congdon et al (2004a). TABLE A-2: PREVALENCE OF AMD BY AGE, GENDER AND WHITE/BLACK (% POPULATION) Age White Female White Male Black Female Black Male 50-54 55-59 60-64 65-69 70-74 75-79 80-84 85+ 0.2 0.2 0.4 0.7 1.5 3.2 6.8 13.6 0.3 0.4 0.6 1.1 2.1 3.9 6.9 12.0 0.9 1.1 1.4 1.7 2.1 2.5 2.9 3.3 0.2 0.4 0.6 0.9 1.5 2.4 3.8 5.9 96 The cost of vision loss in Canada TABLE A-3: PREVALENCE OF CATARACT BY AGE, GENDER AND WHITE/BLACK (% POPULATION) Age White Female White Male Black Female Black Male 40-49 50-54 55-59 60-64 65-69 70-74 75-79 80+ 1.8 5.0 9.4 16.8 27.5 40.8 54.5 72.9 2.8 4.9 8.2 13.8 22.4 34.0 47.2 67.2 2.2 7.3 12.8 20.0 28.5 37.4 46.1 58.2 1.7 4.5 7.6 11.9 17.5 24.1 31.3 43.3 TABLEA-4: PREVALENCE OF DR BY AGE, GENDER AND WHITE/BLACK (% POPULATION) Age White Female White Male Black Female Black Male 18-39 40-49 50-64 65-74 75+ 1.1 1.9 3.3 5.3 5.2 0.7 1.5 4.2 7.6 5.3 0.8 1.9 6.3 6.8 5.8 0.6 1.9 4.3 4.2 4.9 TABLE A-5: PREVALENCE OF GLAUCOMA BY AGE, GENDER AND WHITE/BLACK (% POPULATION) Age White Female White Male Black Female Black Male 40-49 50-54 55-59 60-64 65-69 70-74 75-79 80+ 0.8 0.9 1.0 1.2 1.6 2.2 3.3 6.9 0.4 0.6 0.8 1.2 1.7 2.3 3.2 5.5 2.3 3.0 3.5 4.1 4.8 5.6 6.5 8.3 1.5 2.2 2.9 3.7 4.8 6.2 7.9 11.6 97 The cost of vision loss in Canada TABLE A-6: PREVALENCE OF MYOPIA BY AGE, GENDER AND WHITE/BLACK (% POPULATION) Age White Female White Male Black Female Black Male 40-49 50-54 55-59 60-64 65-69 70-74 75-79 80+ 46.4 30.3 23.7 19.4 16.8 15.5 15.2 16.8 37.0 26.2 22.0 19.4 17.9 17.5 18.0 21.1 18.4 13.2 11.4 10.3 9.8 9.9 10.4 12.7 22.5 16.3 13.1 10.4 8.1 6.3 4.9 3.1 TABLE A-7: PREVALENCE OF HYPEROPIA BY AGE, GENDER AND WHITE/BLACK (% POPULATION) Age White Female White Male Black Female Black Male 40-49 50-54 55-59 60-64 65-69 70-74 75-79 80+ 3.7 7.4 10.5 14.1 17.9 21.6 24.7 28.0 3.6 6.4 8.7 11.4 14.2 17.1 19.9 23.5 3.1 5.4 7.1 8.9 10.6 12.0 13.1 13.6 2.2 3.3 3.8 3.9 3.8 3.3 2.6 1.5 TABLE A-8: PREVALENCE OF ALL VL BY AGE, GENDER AND WHITE/BLACK (% POPULATION) Age 40- 49 50-54 55-59 60-64 65-69 70-74 75-79 80 + 98 White Female White Male Black Female Black Male 0.3 0.4 0.5 0.7 1.2 2.3 4.8 24.1 0.3 0.3 0.4 0.6 1.0 1.9 4.0 20.2 0.1 0.4 0.7 1.3 2.4 4.2 7.0 15.1 0.3 0.7 1.2 2.2 3.8 6.4 10.4 23.7 The cost of vision loss in Canada TABLE A-9: PREVALENCE OF MILD VL BY AGE, GENDER AND WHITE/BLACK (% POPULATION) Age White Female White Male Black 40-49 50-54 55-59 60-64 65-69 70-74 75-79 80 + 0.2 0.2 0.3 0.4 0.7 1.3 2.8 12.3 0.1 0.2 0.2 0.3 0.6 1.0 2.2 9.5 0.0 0.1 0.3 0.6 1.2 2.3 3.8 7.7 TABLE A-10: PREVALENCE OF MODERATE VL BY AGE, GENDER AND WHITE/BLACK (% POPULATION) Age White Female White Male Black 40-49 50-54 55-59 60-64 65-69 70-74 75-79 80 + 0.1 0.1 0.1 0.2 0.3 0.5 1.1 4.9 0.1 0.1 0.1 0.1 0.2 0.4 0.9 3.8 0.0 0.1 0.1 0.3 0.5 0.9 1.5 3.1 TABLE A-11: PREVALENCE OF BLINDNESS BY AGE, GENDER AND WHITE/BLACK (% POPULATION) Age White Female White Male Black Female Black Male 40-49 50-54 55-59 60-64 65-69 70-74 75-79 80 + 0.1 0.1 0.1 0.2 0.2 0.4 0.9 6.8 0.1 0.1 0.1 0.2 0.2 0.4 0.9 6.8 0.1 0.2 0.3 0.4 0.7 1.1 1.7 4.2 0.3 0.5 0.8 1.3 2.0 3.2 5.1 12.8 99 The cost of vision loss in Canada APPENDIX B: PREVALENCE PROJECTIONS BY AGE, GENDER AND DISEASE TABLE B-1: ALL VL BY AGE AND GENDER, 2007-2032 SELECTED YEARS (PEOPLE) 0-4 5-9 10-14 15-19 20-24 25-29 30-34 35-39 40-44 45-49 50-54 55-59 60-64 65-69 70-74 75-79 80-84 85-89 90+ Total males % of males % of total prevalence 0-4 5-9 10-14 15-19 20-24 25-29 30-34 35-39 40-44 45-49 50-54 55-59 60-64 65-69 70-74 75-79 80-84 85-89 90+ Total females % of females % of total prevalence 0-4 5-9 10-14 15-19 20-24 25-29 30-34 35-39 40-44 45-49 50-54 55-59 60-64 65-69 70-74 75-79 80-84 85-89 90+ Total persons % of total population 100 2007 2010 2015 2020 2025 2032 0 0 0 0 0 0 0 0 0 86 24 24 87 9,577 5,028 16,924 28,842 22,096 36,555 38,920 59,237 60,526 42,877 19,296 340,097 2.1% 41.6% 0 0 0 0 49 347 345 205 9,469 5,166 17,390 29,942 23,148 37,979 44,041 75,270 94,066 85,336 54,101 476,854 2.9% 58.4% 0 0 0 93 26 26 94 8,465 5,090 18,076 30,861 25,511 41,772 40,874 60,658 65,860 49,695 22,356 369,458 2.2% 42.0% 0 0 0 0 53 381 377 223 8,388 5,202 18,376 32,271 26,902 43,143 46,199 75,476 96,399 95,603 60,609 509,602 3.0% 58.0% 0 0 0 108 31 30 108 8,009 4,278 18,808 35,009 28,515 54,331 50,178 64,591 72,030 61,082 27,469 424,576 2.5% 42.8% 0 0 0 0 61 442 435 256 7,904 4,429 18,850 36,151 30,400 56,520 56,063 79,852 99,527 108,488 68,785 568,162 3.2% 57.2% 0 0 0 124 35 35 125 8,056 4,076 15,672 36,928 32,472 61,212 65,545 80,323 78,328 70,652 31,774 485,355 2.7% 43.3% 0 0 0 0 70 512 502 295 7,997 4,239 15,750 37,614 34,116 64,140 73,219 97,566 106,756 117,435 74,469 634,679 3.5% 56.7% 0 0 0 143 41 40 144 8,194 4,128 14,856 32,110 34,337 70,126 74,498 106,150 98,929 80,104 36,029 559,828 3.0% 43.7% 0 0 0 0 81 589 579 340 8,149 4,343 14,869 32,816 35,531 72,227 83,586 128,058 131,653 128,081 81,229 722,129 3.8% 56.3% 0 0 0 172 49 48 174 7,903 4,200 15,155 31,493 29,488 71,676 89,502 130,352 140,017 113,655 51,054 684,941 3.6% 43.7% 0 0 0 0 98 712 701 413 7,902 4,471 15,320 32,127 30,500 71,940 97,684 156,188 183,910 170,860 108,336 881,162 4.5% 56.3% 0 0 0 0 135 371 369 292 19,046 10,193 0 0 0 0 147 407 403 318 16,853 10,292 0 0 0 0 169 473 465 364 15,912 8,707 0 0 0 0 195 547 537 420 16,053 8,315 0 0 0 0 224 630 619 484 16,342 8,470 0 0 0 0 270 762 749 587 15,806 8,672 34,315 58,784 45,245 74,534 82,961 134,507 154,591 128,212 73,397 816,951 2.49% 36,452 63,132 52,413 84,915 87,073 136,134 162,258 145,298 82,965 879,059 2.63% 37,658 71,159 58,915 110,851 106,241 144,443 171,557 169,570 96,254 992,738 2.86% 31,421 74,541 66,587 125,352 138,764 177,889 185,084 188,087 106,243 1,120,033 3.10% 29,725 64,925 69,868 142,353 158,084 234,208 230,582 208,185 117,258 1,281,957 3.43% 30,475 63,620 59,987 143,616 187,186 286,541 323,928 284,515 159,390 1,566,103 4.01% The cost of vision loss in Canada TABLE B-2: VL FROM AMD BY AGE AND GENDER, 2007-2032 SELECTED YEARS (PEOPLE) 2007 2010 2015 2020 2025 2032 0-4 5-9 10-14 15-19 20-24 25-29 30-34 35-39 40-44 45-49 50-54 55-59 60-64 65-69 70-74 75-79 80-84 85-89 90+ Total males % of males % of total prevalence 0 0 0 0 0 0 0 0 0 0 0 0 0 519 1,232 6,787 6,161 10,577 6,210 31,486 0.2% 35.4% 0 0 0 0 0 0 0 0 0 0 0 0 0 591 1,304 6,973 6,712 12,251 7,195 35,027 0.2% 35.9% 0 0 0 0 0 0 0 0 0 0 0 0 0 762 1,591 7,462 7,377 15,051 8,841 41,084 0.2% 37.1% 0 0 0 0 0 0 0 0 0 0 0 0 0 861 2,044 9,249 8,061 17,411 10,226 47,853 0.3% 38.4% 0 0 0 0 0 0 0 0 0 0 0 0 0 987 2,327 12,148 10,115 19,743 11,596 56,917 0.3% 39.3% 0 0 0 0 0 0 0 0 0 0 0 0 0 1,027 2,799 14,909 14,179 27,961 16,435 77,309 0.4% 40.1% 0-4 5-9 10-14 15-19 20-24 25-29 30-34 35-39 40-44 45-49 50-54 55-59 60-64 65-69 70-74 75-79 80-84 85-89 90+ Total females % of females % of total prevalence 0 0 0 0 0 0 0 0 0 0 0 0 0 589 1,427 8,402 9,190 20,702 17,227 57,536 0.3% 64.6% 0 0 0 0 0 0 0 0 0 0 0 0 0 666 1,511 8,441 9,436 23,193 19,300 62,546 0.4% 64.1% 0 0 0 0 0 0 0 0 0 0 0 0 0 857 1,826 8,951 9,777 26,315 21,889 69,615 0.4% 62.9% 0 0 0 0 0 0 0 0 0 0 0 0 0 977 2,341 10,926 10,513 28,477 23,675 76,908 0.4% 61.6% 0 0 0 0 0 0 0 0 0 0 0 0 0 1,104 2,675 14,304 12,938 31,053 25,806 87,880 0.5% 60.7% 0 0 0 0 0 0 0 0 0 0 0 0 0 1,140 3,144 17,443 18,004 41,440 34,465 115,636 0.6% 59.9% 0-4 5-9 10-14 15-19 20-24 25-29 30-34 35-39 40-44 45-49 50-54 55-59 60-64 65-69 70-74 75-79 80-84 85-89 90+ Total persons % of total population 0 0 0 0 0 0 0 0 0 0 0 0 0 1,108 2,659 15,189 15,351 31,279 23,437 89,022 0.27% 0 0 0 0 0 0 0 0 0 0 0 0 0 1,257 2,815 15,414 16,148 35,445 26,495 97,573 0.29% 0 0 0 0 0 0 0 0 0 0 0 0 0 1,619 3,416 16,413 17,155 41,366 30,730 110,700 0.32% 0 0 0 0 0 0 0 0 0 0 0 0 0 1,839 4,385 20,175 18,574 45,888 33,901 124,761 0.35% 0 0 0 0 0 0 0 0 0 0 0 0 0 2,092 5,003 26,452 23,053 50,796 37,402 144,797 0.39% 0 0 0 0 0 0 0 0 0 0 0 0 0 2,167 5,943 32,351 32,183 69,402 50,900 192,945 0.49% 101 The cost of vision loss in Canada TABLE B-3: VL FROM CATARACT BY AGE AND GENDER, 2007-2032 SELECTED YEARS (PEOPLE) 2007 2010 2015 2020 2025 2032 0-4 5-9 10-14 15-19 20-24 25-29 30-34 35-39 40-44 45-49 50-54 55-59 60-64 65-69 70-74 75-79 80-84 85-89 90+ Total males % of males % of total prevalence 0 0 0 0 0 0 0 0 0 0 0 980 141 1,102 4,434 9,319 14,164 10,462 7,344 47,945 0.3% 35.8% 0 0 0 0 0 0 0 0 0 0 0 1,055 160 1,254 4,711 9,564 15,420 12,121 8,505 52,789 0.3% 36.3% 0 0 0 0 0 0 0 0 0 0 0 1,205 183 1,608 5,727 10,217 16,903 14,893 10,446 61,183 0.4% 37.3% 0 0 0 0 0 0 0 0 0 0 0 1,295 210 1,821 7,298 12,678 18,421 17,227 12,084 71,034 0.4% 38.3% 0 0 0 0 0 0 0 0 0 0 0 1,196 230 2,087 8,316 16,687 23,197 19,534 13,704 84,952 0.5% 39.1% 0 0 0 0 0 0 0 0 0 0 0 1,237 234 2,190 10,005 20,483 32,688 27,680 19,393 113,910 0.6% 39.8% 0-4 5-9 10-14 15-19 20-24 25-29 30-34 35-39 40-44 45-49 50-54 55-59 60-64 65-69 70-74 75-79 80-84 85-89 90+ Total females % of females % of total prevalence 0 0 0 0 0 0 0 0 0 0 0 967 138 1,371 5,892 12,651 22,914 21,170 20,788 85,891 0.5% 64.2% 0 0 0 0 0 0 0 0 0 0 0 1,046 158 1,547 6,301 12,810 23,614 23,716 23,288 92,480 0.5% 63.7% 0 0 0 0 0 0 0 0 0 0 0 1,180 182 1,969 7,581 13,715 24,641 26,949 26,457 102,673 0.6% 62.7% 0 0 0 0 0 0 0 0 0 0 0 1,247 207 2,251 9,534 16,672 26,616 29,233 28,689 114,448 0.6% 61.7% 0 0 0 0 0 0 0 0 0 0 0 1,139 225 2,550 10,912 21,597 32,627 31,930 31,328 132,307 0.7% 60.9% 0 0 0 0 0 0 0 0 0 0 0 1,163 226 2,692 12,897 26,318 45,067 42,468 41,688 172,519 0.9% 60.2% 0 0 0 0 0 0 0 0 0 0 0 1,947 279 2,473 10,325 21,970 37,077 31,632 28,133 133,836 0.41% 0 0 0 0 0 0 0 0 0 0 0 2,101 318 2,800 11,012 22,374 39,034 35,836 31,793 145,268 0.44% 0 0 0 0 0 0 0 0 0 0 0 2,385 365 3,577 13,308 23,932 41,544 41,841 36,903 163,856 0.47% 0 0 0 0 0 0 0 0 0 0 0 2,542 417 4,071 16,831 29,351 45,037 46,459 40,773 185,482 0.51% 0 0 0 0 0 0 0 0 0 0 0 2,335 455 4,637 19,228 38,284 55,824 51,464 45,032 217,259 0.58% 0 0 0 0 0 0 0 0 0 0 0 2,400 460 4,882 22,902 46,801 77,754 70,148 61,081 286,428 0.73% 0-4 5-9 10-14 15-19 20-24 25-29 30-34 35-39 40-44 45-49 50-54 55-59 60-64 65-69 70-74 75-79 80-84 85-89 90+ Total persons % of total population 102 The cost of vision loss in Canada TABLE B-4: VL FROM DR BY AGE AND GENDER, 2007-2032 SELECTED YEARS (PEOPLE) 2007 2010 2015 2020 2025 2032 0-4 5-9 10-14 15-19 20-24 25-29 30-34 35-39 40-44 45-49 50-54 55-59 60-64 65-69 70-74 75-79 80-84 85-89 90+ Total males % of males % of total prevalence 0 0 0 0 86 24 24 87 87 55 933 1,740 1,717 1,472 869 2,125 2,138 886 318 12,560 0.1% 42.0% 0 0 0 0 93 26 26 94 94 60 998 1,883 1,957 1,665 933 2,212 2,330 1,023 367 13,763 0.1% 42.3% 0 0 0 0 108 31 30 108 108 69 1,045 2,164 2,225 2,096 1,124 2,411 2,566 1,254 449 15,786 0.1% 42.8% 0 0 0 0 124 35 35 125 124 79 889 2,362 2,551 2,389 1,397 2,953 2,807 1,451 519 17,840 0.1% 43.0% 0 0 0 0 143 41 40 144 143 91 856 2,292 2,772 2,740 1,596 3,789 3,516 1,647 590 20,400 0.1% 43.1% 0 0 0 0 172 49 48 174 173 110 888 2,467 2,706 2,977 1,923 4,639 4,913 2,310 822 24,373 0.1% 43.1% 0-4 5-9 10-14 15-19 20-24 25-29 30-34 35-39 40-44 45-49 50-54 55-59 60-64 65-69 70-74 75-79 80-84 85-89 90+ Total females % of females % of total prevalence 0 0 0 0 49 347 345 205 206 232 1,112 1,997 1,971 1,544 937 2,643 3,237 1,706 829 17,360 0.1% 58.0% 0 0 0 0 53 381 377 223 223 252 1,184 2,177 2,255 1,738 1,006 2,704 3,334 1,911 929 18,746 0.1% 57.7% 0 0 0 0 61 442 435 256 254 289 1,245 2,493 2,595 2,196 1,208 2,931 3,474 2,174 1,057 21,112 0.1% 57.2% 0 0 0 0 70 512 502 295 293 333 1,123 2,719 2,954 2,515 1,507 3,545 3,749 2,363 1,149 23,630 0.1% 57.0% 0 0 0 0 81 589 579 340 338 384 1,122 2,697 3,198 2,854 1,726 4,529 4,599 2,585 1,257 26,877 0.1% 56.9% 0 0 0 0 98 712 701 413 410 465 1,217 2,946 3,197 3,057 2,045 5,514 6,362 3,428 1,667 32,230 0.2% 56.9% 0-4 5-9 10-14 15-19 20-24 25-29 30-34 35-39 40-44 45-49 50-54 55-59 60-64 65-69 70-74 75-79 80-84 85-89 90+ Total persons % of total population 0 0 0 0 135 371 369 292 293 287 2,045 3,737 3,688 3,015 1,805 4,769 5,376 2,591 1,147 29,920 0.09% 0 0 0 0 147 407 403 318 317 312 2,182 4,060 4,212 3,403 1,940 4,917 5,664 2,934 1,296 32,509 0.10% 0 0 0 0 169 473 465 364 362 358 2,290 4,658 4,820 4,292 2,333 5,342 6,039 3,428 1,506 36,897 0.11% 0 0 0 0 195 547 537 420 417 413 2,012 5,081 5,505 4,904 2,904 6,497 6,556 3,814 1,669 41,471 0.11% 0 0 0 0 224 630 619 484 481 475 1,978 4,989 5,970 5,594 3,322 8,318 8,115 4,231 1,847 47,277 0.13% 0 0 0 0 270 762 749 587 584 575 2,104 5,413 5,903 6,034 3,968 10,153 11,275 5,738 2,489 56,603 0.15% 103 The cost of vision loss in Canada TABLE B-5: VL FROM GLAUCOMA BY AGE AND GENDER, 2007-2032 SELECTED YEARS (PEOPLE) 104 2007 2010 2015 2020 2025 2032 0-4 5-9 10-14 15-19 20-24 25-29 30-34 35-39 40-44 45-49 50-54 55-59 60-64 65-69 70-74 75-79 80-84 85-89 90+ Total males % of males % of total prevalence 0 0 0 0 0 0 0 0 0 0 0 0 0 1,288 1,410 1,364 3,928 1,611 605 10,206 0.1% 40.9% 0 0 0 0 0 0 0 0 0 0 0 0 0 1,460 1,506 1,402 4,276 1,865 701 11,211 0.1% 41.7% 0 0 0 0 0 0 0 0 0 0 0 0 0 1,855 1,824 1,502 4,689 2,291 860 13,020 0.1% 42.9% 0 0 0 0 0 0 0 0 0 0 0 0 0 2,107 2,297 1,860 5,112 2,650 995 15,021 0.1% 43.7% 0 0 0 0 0 0 0 0 0 0 0 0 0 2,417 2,621 2,441 6,435 3,005 1,129 18,047 0.1% 44.2% 0 0 0 0 0 0 0 0 0 0 0 0 0 2,584 3,155 2,996 9,062 4,251 1,593 23,641 0.1% 44.5% 0-4 5-9 10-14 15-19 20-24 25-29 30-34 35-39 40-44 45-49 50-54 55-59 60-64 65-69 70-74 75-79 80-84 85-89 90+ Total females % of females % of total prevalence 0 0 0 0 0 0 0 0 0 0 0 0 0 1,099 1,194 1,853 5,828 3,119 1,639 14,731 0.1% 59.1% 0 0 0 0 0 0 0 0 0 0 0 0 0 1,245 1,260 1,880 5,965 3,495 1,836 15,680 0.1% 58.3% 0 0 0 0 0 0 0 0 0 0 0 0 0 1,614 1,525 2,018 6,145 3,965 2,083 17,349 0.1% 57.1% 0 0 0 0 0 0 0 0 0 0 0 0 0 1,836 1,971 2,450 6,581 4,290 2,253 19,381 0.1% 56.3% 0 0 0 0 0 0 0 0 0 0 0 0 0 2,072 2,251 3,165 8,126 4,677 2,457 22,749 0.1% 55.8% 0 0 0 0 0 0 0 0 0 0 0 0 0 2,109 2,639 3,857 11,379 6,243 3,280 29,507 0.1% 55.5% 0-4 5-9 10-14 15-19 20-24 25-29 30-34 35-39 40-44 45-49 50-54 55-59 60-64 65-69 70-74 75-79 80-84 85-89 90+ Total persons % of total population 0 0 0 0 0 0 0 0 0 0 0 0 0 2,386 2,605 3,217 9,755 4,730 2,244 24,937 0.08% 0 0 0 0 0 0 0 0 0 0 0 0 0 2,705 2,766 3,282 10,241 5,360 2,537 26,891 0.08% 0 0 0 0 0 0 0 0 0 0 0 0 0 3,469 3,348 3,520 10,834 6,255 2,943 30,368 0.09% 0 0 0 0 0 0 0 0 0 0 0 0 0 3,944 4,268 4,311 11,693 6,940 3,248 34,403 0.10% 0 0 0 0 0 0 0 0 0 0 0 0 0 4,489 4,872 5,607 14,561 7,683 3,585 40,797 0.11% 0 0 0 0 0 0 0 0 0 0 0 0 0 4,692 5,794 6,852 20,441 10,494 4,873 53,147 0.14% The cost of vision loss in Canada TABLE B6: VL FROM RE BY AGE AND GENDER, 2007-2032 SELECTED YEARS (PEOPLE) 2007 2010 2015 2020 2025 2032 0-4 5-9 10-14 15-19 20-24 25-29 30-34 35-39 40-44 45-49 50-54 55-59 60-64 65-69 70-74 75-79 80-84 85-89 90+ Total males % of males % of total prevalence 0 0 0 0 0 0 0 0 9,490 4,973 15,991 26,122 20,239 32,174 30,975 39,642 34,134 19,342 4,819 237,900 1.5% 44.1% 0 0 0 0 0 0 0 0 8,371 5,030 17,078 27,923 23,395 36,802 32,419 40,506 37,121 22,435 5,589 256,668 1.6% 44.5% 0 0 0 0 0 0 0 0 7,901 4,209 17,763 31,639 26,108 48,010 39,912 42,999 40,495 27,594 6,873 293,503 1.7% 45.1% 0 0 0 0 0 0 0 0 7,932 3,997 14,783 33,271 29,711 54,033 52,508 53,583 43,927 31,913 7,949 333,606 1.9% 45.5% 0 0 0 0 0 0 0 0 8,051 4,037 14,000 28,622 31,334 61,895 59,638 71,084 55,665 36,174 9,011 379,511 2.1% 45.6% 0 0 0 0 0 0 0 0 7,730 4,090 14,268 27,788 26,547 62,898 71,620 87,326 79,176 51,454 12,812 445,709 2.3% 45.6% 0-4 5-9 10-14 15-19 20-24 25-29 30-34 35-39 40-44 45-49 50-54 55-59 60-64 65-69 70-74 75-79 80-84 85-89 90+ Total females % of females % of total prevalence 0 0 0 0 0 0 0 0 9,264 4,934 16,278 26,978 21,039 33,378 34,592 49,720 52,897 38,638 13,617 301,336 1.8% 55.9% 0 0 0 0 0 0 0 0 8,165 4,950 17,193 29,048 24,489 37,948 36,121 49,641 54,050 43,288 15,256 320,149 1.9% 55.5% 0 0 0 0 0 0 0 0 7,649 4,140 17,605 32,477 27,623 49,883 43,923 52,237 55,491 49,086 17,299 357,414 2.0% 54.9% 0 0 0 0 0 0 0 0 7,704 3,905 14,626 33,647 30,954 56,561 57,867 63,972 59,297 53,073 18,703 400,310 2.2% 54.5% 0 0 0 0 0 0 0 0 7,811 3,959 13,748 28,979 32,108 63,647 66,021 84,462 73,363 57,836 20,381 452,316 2.4% 54.4% 0 0 0 0 0 0 0 0 7,492 4,007 14,103 28,018 27,077 62,943 76,960 103,057 103,099 77,281 27,235 531,271 2.7% 54.4% 0-4 5-9 10-14 15-19 20-24 25-29 30-34 35-39 40-44 45-49 50-54 55-59 60-64 65-69 70-74 75-79 80-84 85-89 90+ Total persons % of total population 0 0 0 0 0 0 0 0 18,753 9,907 32,269 53,100 41,278 65,552 65,567 89,362 87,032 57,980 18,436 539,236 1.64% 0 0 0 0 0 0 0 0 16,536 9,980 34,270 56,971 47,884 74,750 68,540 90,147 91,171 65,724 20,845 576,817 1.73% 0 0 0 0 0 0 0 0 15,551 8,349 35,368 64,116 53,731 97,893 83,835 95,236 95,986 76,680 24,172 650,917 1.87% 0 0 0 0 0 0 0 0 15,636 7,902 29,409 66,918 60,665 110,594 110,376 117,555 103,224 84,986 26,652 733,916 2.03% 0 0 0 0 0 0 0 0 15,862 7,996 27,748 57,601 63,443 125,542 125,659 155,547 129,029 94,010 29,391 831,827 2.23% 0 0 0 0 0 0 0 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