Medical Costs per QALY of Statins Using the Swiss

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Medical Costs per QALY of Statins Using the Swiss
Medical Costs per QALY of Statins Using SMB assumptions
SGIM Annual Meeting 2015 (FM277): M. Romanens et al / www.varifo.ch
Medical Costs per QALY of Statins Using the
Swiss Medical Board (SMB) assumptions:
Observed Effects in Two Large Primary
Prevention Cohorts from Germany and
Switzerland
Michel Romanens1, Franz Ackermann1, Thomas Szucs2, Isabella
Sudano3, Ansgar Adams4
1
2
3
4
Vascular Risk Foundation (Varifo), Olten
European Centre of Pharmaceutical Medicine (ECPM), Basel
University Heart Center Cardiology, University Hospital Zürich, Zürich,
Switzerland,
Gesundheitsvorsorge und Sicherheitstechnik GmbH, Bonn, Germany
Medical Costs per QALY of Statins Using SMB assumptions
SGIM Annual Meeting 2015 (FM277): M. Romanens et al / www.varifo.ch
Background
- In June 2014 the SMB publishes a report showing costs per quality
adjusted life years (Costs/QALY) to be extremely unfavorable (210’000
SFr) for statins in primary care in subjects having an ESC risk of 0.9% in
5 years.
- As a consequence, in otherwise cardiovascular healthy subjects without
diabetes mellitus or familial hypercholesterolemia, the SMB recommends
statins in primary care only in subjects with a calculated ESC risk of
≥7.5% in 10 years.
- The rationale for this apparent gap warrants further elucidation.
- Further, costs/QALY at various cutoffs and it’s effect in cardiovascular
disease prevention at the primary care level have not yet been reported.
- The SMB Statin report is available at http://www.medicalboard.ch/fileadmin/docs/public/mb/Fachberichte/2014-0721_Bericht_Statine_Final_Anpassung.pdf
Medical Costs per QALY of Statins Using SMB assumptions
SGIM Annual Meeting 2015 (FM277): M. Romanens et al / www.varifo.ch
AIMS
- We aim to determine Costs/QALY for various cutoffs of ESC risk using
the SMB assumptions.
- We aim to determine, whether Costs/QALY at different ESC risk levels
correlate with the number needed to treat (NNT) in the SMB
assumptions.
- Based on various NNT, we aim to derive the ideal ESC risk cutoff for
costs/QALY, allowing an NNT of 25 to be adequate.
- We aim to test various ESC risk cutoffs in two large healthy populations
from Switzerland (CH) and Germany (DE) to detect a coronary risk
equivalents defined by the total carotid plaque burden, a highly sensitive
and specific marker of future fatal and nonfatal myocardial infarction.
Medical Costs per QALY of Statins Using SMB assumptions
SGIM Annual Meeting 2015 (FM277): M. Romanens et al / www.varifo.ch
METHODS (1)
- The EFFECT MODEL of the SMB to calculate costs/QALY is:
- for 1 fatal AMI, 4.5 nonfatal AMI occur
- relative risk reduction per 1 mmol/l LDL is 22%
- cost per fatal AMI is CHF 8'500, per nonfatal AMI is CHF 25'000 in
the first year and CHF 8'000 in subsequent years
- loss of QALY is 1.0 for fatal and 0.2 for nonfatal AMI
- annual preventive medical cost per individual including statin costs
CHF 470 SFr
- all AMI events occur uniformly after 50% of the total observation
time.
- The calculations are available at www.varifo.ch/QALYVarifo.xlsx
Medical Costs per QALY of Statins Using SMB assumptions
SGIM Annual Meeting 2015 (FM277): M. Romanens et al / www.varifo.ch
METHODS (2)
- We defined the numbers of subjects exhibiting a coronary risk equivalent
using carotid atherosclerotic plaque imaging and calculated the
sensitivity (SENS) and the specificity (SPEC) of various ESC cutoffs to
detect these subjects.
- SENS: sensitivity deals with the diseased subjects
- [true positives] / [true positives and false negatives]
- SPEC: specificity deals with the healthy subjects
- [true negatives] / [true negatives and false positives]
- NNT: 1 / absolute risk reduction
- Examples:
- 10% absolute risk reduction = 100/10 = NNT 10
- 1% absolute risk reduction = 100/1 = NNT 100
Medical Costs per QALY of Statins Using SMB assumptions
SGIM Annual Meeting 2015 (FM277): M. Romanens et al / www.varifo.ch
METHODS (3)
- Carotid imaging were obtained by ultrasound (linear probe 7-14 MHz)
- Imaging was performed with the identical imaging technique in CH and
DE
- Total Carotid Plaque Burden was determined from both carotid arteries
- Each carotid plaque was traced longitudinally and added together,
ending up with the total plaque area (TPA) in mm2.
- we used TPA ≥80 mm2 (TPA80) to define high long-term (≥20% in ≥10
years) coronary risk (Arterioscler Thromb Vasc Biol. 2014;34:226-230)
Medical Costs per QALY of Statins Using SMB assumptions
SGIM Annual Meeting 2015 (FM277): M. Romanens et al / www.varifo.ch
RESULTS (1)
- 1
Medical Costs per QALY of Statins Using SMB assumptions
SGIM Annual Meeting 2015 (FM277): M. Romanens et al / www.varifo.ch
RESULTS (1)
- 1
Medical Costs per QALY of Statins Using SMB assumptions
SGIM Annual Meeting 2015 (FM277): M. Romanens et al / www.varifo.ch
Results (2)
Sensitivity and specificity of ESC risk cutoffs the detect a
coronary risk equivalent defined by carotid plaque imaging
(TPA)
Population (N)
Female (%)
Mean age (years±SD)
TPA ≥80 mm2
SENS/SPEC ESC 1.8% 10 years
SENS/SPEC ESC 3.3% 10 years
SENS/SPEC ESC 5.0% 10 years
SENS/SPEC ESC 7.5% 10 years
CH
2203
1083 (49%)
57±7
22%
60/79
30/93
11/98
4/99
DE
2942
989 (34%)
46±10
15%
30/95
7/100
2/100
0.5/100
Medical Costs per QALY of Statins Using SMB assumptions
SGIM Annual Meeting 2015 (FM277): M. Romanens et al / www.varifo.ch
Discussion (1)
Costs/QALY
- Using the Costs/QALY assumptions of the SMB we find that the effect of
statins correlates with the NNT.
- Using a model with an ESC risk of 0.9% in 5 years, costs/QALY are
210’000 SFr. (NNT 91)
- Using a Model with an ESC risk of 7.5% in 10 years, costs/QALY are
2’089 SFr. (NNT 11)
- The middle way cutoff may be more suitable:
- Using a Model with an ESC risk of 3.3% in 10 years, costs/QALY are
40’261 SFr. (NNT 25)
NNT
Medical Costs per QALY of Statins Using SMB assumptions
SGIM Annual Meeting 2015 (FM277): M. Romanens et al / www.varifo.ch
Discussion (2)
- The conclusion of the SMB has to be questioned, since there is a gap
between the presented costs/QALY of 210’000 SFr and the
recommended cutoff of ESC 7.5% to treat with statins.
- Using the SMB cutoff of ESC 7.5% would leave near 100% of healthy
subjects with a coronary risk equivalent untreated with statins.
- Using the SMB cutoff of ESC 7.5% creates an obsolescence for
measuring Cholesterol in primary care.
Medical Costs per QALY of Statins Using SMB assumptions
SGIM Annual Meeting 2015 (FM277): M. Romanens et al / www.varifo.ch
Conclusion
- We find statins to have costs per 1 mmol/l of LDL reduction of CHF
40'000/QALY (NNT 25) for an ESC risk of 3.3%, when we use the SMB
assumptions.
- With ESC 7.5% (SMB guide), many subjects with confirmed high risk
atherosclerosis would presumably not be treated (SENS 4% in CH, 0.5%
in DE), creating a situation, where there is an obsolescence for
Cholesterol measurements (because high LDL would not be treated
anyway).
- Further studies are needed to test the SMB statin effect assumptions,
since the SMB assumptions have not been evidenced in reality.
- In the future, costs per QALY should be calculated with inclusion of
medical and social costs.
- In the mean time, we strongly recommend to adhere to the international
guidelines for initiation of statin treatments in healthy subjects.