Renal Nutrition News – Karolinska Institutet Advanced Renal

Renal Nutrition
News
Karolinska Institutet Advanced Renal
Nutrition Conference 2013, Stockholm
March 2013
Highlights from the 5th Karolinska
Institutet Advanced Renal
Nutrition Conference
• Protein-energy wasting (PEW) in people with chronic kidney disease (CKD) includes aspects of undernutrition and increased catabolism (p 2).
• The prevalence of PEW is high: 15
to 18% in CKD stages 3 and 4,
and up to 50% in patients on
dialysis (p 4).
• In management of patients
with CKD, Dr Kalantar-Zadeh
emphasizes that monitoring and
preserving nutritional status should
be a high priority (p 5).
• Tools for screening and assessment
of malnutrition are evaluated for
their relevance to CKD (p 6).
• What daily protein and energy intake targets are advised for people with renal disease (p 7)?
• Giving oral nutritional supplements
(ONS) during hemodialysis is a
rational strategy to prevent or
treat PEW, and is associated with
improved patient survival (p 9).
• With a recent algorithm, experts
guide practitioners through logical
steps for managing the nutritional
needs of CKD patients (p 10).
• Close the nutrition gap to prevent
PEW. Dr Nikolina Basic Jukic
(Croatia) stated, “At our dialysis
center, all patients receive ONS to
prevent PEW” (p 11).
The 5th Karolinska Institutet Advanced Renal Nutrition Conference took place in Stockholm, Sweden on
March 13-15, 2013. The bust of Alfred Nobel stands outside the Nobel Forum where the 2013 confer­
ence was held. Organizers, Dr Peter Stenvinkel and Dr Juan-Jesús Carrero, remarked that this confer­
ence originated 5 years ago as a way to bridge the gap between science and clinical practice in renal
nutrition.
The 5th Karolinka Advanced Renal Nutrition Conference convened on March
13, 2013, with a record-breaking 110 participants from 18 different countries.
Drs Peter Stenvinkel and Juan-Jesús Carrero, of the Karolinska Institutet
Division of Renal Medicine, led the conference.
People with chronic kidney disease (CKD) remain at high risk for nutritional
shortfall and protein-energy wasting (PEW). Kidney disease patients often
eat poorly due to the highly restrictive kidney-specific diet and to disease­
related anorexia. Wasting is caused in part by persistent inflammation, which
results from kidney disease and from its treatment (dialysis). Together, these
conditions set the stage for the program of the Advanced Renal Nutrition
Conference. This issue of Renal Nutrition News summarizes the lectures
and discussions by leading renal nutrition researchers and educators on the
nutrition-related condition of protein-energy wasting (PEW) with CKD.
This meeting was sponsored by Abbott Nutrition and endorsed by the
International Society of Renal Nutrition and Metabolism (ISRNM), the European
Renal Association-European Dialysis and Transplantation Association (ERA­
EDTA), the Spanish Society of Nephrology (SEN), and the Centre for Gender
Medicine.
The 5th Karolinska
Conference
makes kidney
nutrition come
alive
The 5th Karolinska Advanced Renal Nutrition Conference
focused on four key topics in renal nutrition: (1) the
pathophysiology of PEW in CKD, (2) tools for nutrition
screening and assessment, (3) nutrition management
for people with CKD, and (4) selected topics: roles
of exercise, dietary fat, vegetarian foods, and fiber in
nutritional management for CKD patients. In addition, the
conference highlighted country-specific challenges and
solutions for managing CKD in Brazil, Croatia, Panama,
Japan, and India.
Pathophysiology,
consequences,
and prevalence
of PEW
People with CKD are at high risk of undernutrition, which
can progress to PEW if it is not diagnosed and treated.
Dr Juan-Jesús Carrero defined PEW as a condition of
decreased body stores of protein and energy, or simply
stated, reduced muscle and fat mass.1 Due to this high
risk for PEW, nutrition plays a key role in managing
patients with kidney disease.
Dr Juan-Jesús Carrero, Karolinska Institutet, Stockholm, Sweden
Pathophysiology: undernutrition
Protein-energy wasting or PEW is a relatively new term
that is aptly applied to the combination of nutritional
and metabolic disturbances present in CKD. PEW is
considered a single pathological entity, yet it includes
elements of both undernutrition and increased
catabolism.
It has long been recognized that spontaneous protein
intake declines with progression of CKD; inadequate
intake of dietary protein and energy becomes particularly
severe in patients with end-stage renal disease and on
dialysis. Dr Carrero advised, “About half of all patients on
hemodialysis report loss of appetite.”2
Anorexia leads to inadequate dietary intake.3 Many
factors contribute to anorexia—retention of uremic toxins,
metabolic acidosis, and increased inflammation due to
kidney, cardiovascular, and other diseases. Additionally,
conditions associated with CKD—depression, physical
inactivity, and the dialysis procedure per se—can worsen
anorexia and accelerate PEW.4
Protein-energy wasting (PEW)
Undernutrition
Wasting/catabolism
Inadequate
diet, anorexia
Inflammation:
cytokines and
adipokines
Metabolic acidosis,
reduced anabolic drive,
insulin resistance,
dialysis, sedentary
lifestyle
2
Pathophysiology: wasting
Reduced anabolic drive. Dr Ikizler advised, “Dialysis
is a lifesaving procedure,
but it is non-physiological
and stressful. Dialysis
itself leads to protein
loss.” Protein synthesis
is limited by the reduced
availability of amino acids
but can be at least partly
restored by consuming
protein or amino acids.7
Intradialytic oral nutrition
is well recognized as a
way to improve protein
homeostasis in dialysis
patients, and to provide
Dr Alp Ikizler (USA)
a longer anabolic effect
post-dialysis compared to
intradialytic total parenteral nutrition (IDPN).8
Drs Peter Stenvinkel
(Sweden) and Alp
Ikizler (USA) provided
an overview of the
physiologic mechanisms
contributing to muscle
loss in PEW: increased
energy expenditure and
catabolism along with
decreased anabolism.4, 5
According to Dr
Stenvinkel, having
CKD “is like getting
old.” Both conditions
Dr Peter Stenvinkel (Sweden)
have many features in common: atherosclerosis, osteoporosis, sarcopenia, poor wound healing, hypogonadism, skin atrophy, depression, and frailty.6
Increased inflammation and inadequate dietary intake are factors that are common in many of these conditions. In addition, metabolic acidosis in patients on
hemodialysis often alters protein metabolism by
enhancing degradation; however, correction of acidosis
with bicarbonate treatment helps restore protein
homeostasis. A sedentary lifestyle coupled with CKD
may also blunt anabolic responses. Exercise, therefore,
may play a key role in preventing or delaying PEW,
although the best type and duration of exercise is still
unknown.
Increased energy expenditure. Reduction in kidney function is associated with an inflammatory response in both mild and advanced CKD. In CKD, inflammation is a major contributor to the development of PEW and the associated loss of muscle. Persistent inflammation is associated with the production of cytokines and adipokines, e.g., C-reactive protein (CRP), interleukin-6 (IL-6), and tumor necrosis factor alpha (TNF-α), which promote increased energy expenditure.4
Mechanisms of muscle loss due to
increased inflammation and catabolism
in CKD5
Direct and indirect catabolic effects. Direct catabolic effects of CKD occur when the inflammatory mediator TNF-related weak inducer of apoptosis (TWEAK) activates protein degradation by way of nuclear factor-κB (NF-κB) and the ubiquitin-proteasome pathway. To make matters worse, elevated levels of myostatin and/or corticosteroids support catabolism indirectly by inhibiting the usual anabolic responses to insulin. CKD also promotes catabolism indirectly by way of abnormalities in the excretion, synthesis, and action of many hormones—a consequence of the kidneys’ role as an endocrine organ. Thus, the usual anabolic actions of insulin, insulin-like growth factor-1 (IGF-1), growth hormone, and testosterone are reduced. Such effects result in lowered muscle synthesis, which can progress to PEW if untreated. Further studies on replacement of anabolic hormones in CKD are needed. Effect
Mechanisms and
mediators of muscle loss
Increased
energy
expenditure
• Production of inflammatory
cytokines; CRP, IL-6, and
TNF-α
Direct catabolic
effects
Indirect
catabolic
effects
Reduced
anabolic
drive
3
• Protein degradation via
TWEAK, NF-κB, and the
ubiquitin-proteasome
pathway
• Insulin deficiency, increased
levels of myostatin or
corticosteroids
• Lowered responses to
insulin, IGF-1, growth
hormone, lowered
testosterone
• Limited supplies of protein/
amino acids
• Metabolic acidosis
• Sedentary lifestyle
Consequences of PEW in CKD
on kidney function. Further, low intakes of micronutrients
also associate with CVD;14 deficiencies of vitamins A,
C, D and K exacerbate inflammation, oxidative stress,
and vascular calcification. Subclinical hypothyroidism is
also common among those with CKD and PEW. With
starvation, the body compensates by reducing thyroid
hormone production to reduce energy expenditure
and minimize protein catabolism. In the short term,
these changes are beneficial. In CKD, however, long­
term reduction of thyroid activity results in subclinical
hypothyroidism/low T3 syndrome, which increases the
risk of CVD mortality.15
Metabolic and physical changes resulting from PEW
have serious negative consequences on physical
functionality, quality of life, survival, and cardiovascular
health.
Poor quality of life, reduced functionality,
increased risk of death
PEW increases the risk of poor outcomes for CKD
patients. These outcomes include poor quality of life,
reduced physical and mental function, and increased
risk of death.
Prevalence of PEW is high with CKD
• 15 to 18% in CKD stages 3 and 4
• 35 to 50% in patients on hemo- or
peritoneal dialysis
• 30% in post-transplant patients
The link between nutritional status and quality of
life is well supported. Hemodialysis patients with
lower serum albumin levels perceive a poorer
quality of life.9 Poor quality of life in turn predicts a
higher risk for mortality in hemodialysis patients.9
Furthermore, hemodialysis patients (n=809) with the
worst malnutrition-inflammation scores (MIS) had
significantly lower quality of life in terms of general
health, physical role and functionality, and emotional
and mental health.10 In CKD patients not on dialysis, low
serum albumin levels likewise predict mortality.11
Prevalence
Dr Carrero noted, “The reported prevalence of PEW
in CKD patients varies widely and depends on the
method of measurement, selected cutoff points, and
geographical location.” For example, when different
diagnostic criteria were used, the prevalence of
malnutrition in peritoneal dialysis patients ranged
between 24% (body mass index < 23 kg/m2) and 65%
(Subjective Global Assessment score 2-5).16 In his
review of the available studies, Dr Carrero found that
the prevalence of PEW is 15% to 18% in stages 3 and
4 patients; 35% to 50% in patients on hemodialysis or
peritoneal dialysis; and 30% in post-transplant patients.
Since studies typically enroll stable patients, these are
likely low estimates.
The only surprise is an association between obesity
and increased CKD survival, which has been called
the “obesity paradox.”12 Being overweight or obese
is protective in CKD patients, unlike in the general
population. CKD patients are more at risk from the
short-term consequences of PEW; they do not live long
enough to die of the adverse effects associated with
obesity.
Cardiovascular disease
It is well known that CKD patients with PEW are at
increased risk of cardiovascular disease (CVD). Dr JuanJesús Carrero made a case for how PEW promotes CVD
risk. In his view, patients with kidney disease and PEW
are at increased risk of CVD because they experience
nutritional deficiencies, excessive catabolism and
inflammation, and hypothyroidism.
Undernutrition and catabolism of protein­
energy wasting in CKD can lead to
cardiovascular disease.
The undernutrition and catabolism of PEW in CKD can
lead to heart disorders.1, 13 In severe starvation, the
heart muscle is catabolized, reducing its ability to handle
fluid challenges, which results in significant edema and
oxidative stress. Such changes promote cardiovascular
disease, and low cardiac output in turn puts more strain
4
do conventional risk factors (obesity, hypertension, and
high serum cholesterol).10, 12, 17 Among biomarkers of
nutritional status, low serum albumin is by far
the strongest predictor of poor survival in dialysis
patients, and serum prealbumin may be even more
sensitive.18, 19 A nutritional intervention that can increase
serum albumin by as little as 0.2 g/dL can have an
important positive impact on survival of CKD patients.
Dr Kalantar-Zadeh reminded us that new International
Society of Nutrition and Metabolism (ISRNM) guidelines
will soon be released and will emphasize the prevention
and treatment of PEW and malnutrition.20
Diagnosis of PEW: criteria
and tools
Dr Kamyar Kalantar-Zadeh, University of California Irvine, USA
Dr Carrero discussed PEW diagnostic criteria from
the ISRNM.1 He reported that these multiple criteria
emphasize the multifaceted nature of PEW. However, Dr
Carrero stated that debate continues about how many
categories must have positive test results in order to
support a PEW diagnosis. He advised that PEW is likely
to be under-diagnosed if a single category/test is used.1
For example, serum albumin is a good predictor of
survival in CKD,11, 18 but measurement of albumin alone
is insufficient to define nutritional status. On the other
hand, a requirement for a positive test in 3 of the 4
categories appears to be too strict a cutoff. Dr Carrero
stressed that these criteria can be used for patient
monitoring, but no specific combination has yet proven
definitive for diagnosis. Clinical judgment remains key.
PEW awareness: a call
to action
The CKD population is unique in that their likelihood
of becoming malnourished is predictable. For care of
patients with CKD, including those in early stages of
disease, Dr Kamyar Kalantar-Zadeh (USA) emphasized
that the highest priority should go to assesssing and
improving nutritional status.
Dr Kalantar-Zadeh pointed out, “Regular nutritional
surveillance in patients with kidney disease facilitates
the diagnosis of wasting before frank PEW is evident.”
The importance of nutrition is clear. Measures of
nutritional status better correlate with CKD mortality than
ISRNM criteria for the clinical diagnosis of PEW in people with kidney disease1
Category
Test
Serum chemistry
• Serum albumin <3.8 g/dL (Bromocresol Green)
• Serum prealbumin (transthyretin) <30 mg/dL (for maintenance dialysis patients
only; levels may vary according to GFR level for patients with CKD stages 2–5)
• Serum cholesterol <100 mg/dL
Body mass
• BMI <23 kg/m2
• Unintentional weight loss over time: 5% over 3 months or 10% over 6 months
• Total body fat percentage <10%
Muscle mass
• Muscle wasting: muscle mass reduced by 5% over 3 months or 10% over
6 months
• Reduced mid-arm muscle circumference area (reduction >10% in relation to 50th
percentile of reference population)
• Creatinine appearance
Dietary intake
• Unintentionally low DPI <0.80 g/kg BW/day for at least 2 months for dialysis
patients or <0.6 g/kg BW/day for patients with CKD stages 2–5
• Unintentionally low DEI <25 kcal/kg BW/day for at least 2 months
Abbreviations: BMI=body mass index; DEI= dietary energy intake; DPI=dietary protein intake; GFR=glomerular filtration rate
5
Tools for nutrition screening
and assessment
Since CKD patients are at high risk for malnutrition and
have an associated risk for death, it is important to
screen for and quantify these risks. Dr Alison Steiber
(USA) reviewed screening and assessment tools for
their relevance and applicability to CKD.
Dr Alison Steiber, Academy of Nutrition and Dietetics, Chicago, USA
Screening Tools
MUST and MST.21 Of all screening tools available,
Dr. Steiber recommends using either MUST or MST to
screen all CKD patients, as these screening tools are
widely used in renal patients.
Handgrip strength.22 Clinicians are increasingly called
upon to measure parameters and predict outcomes
that matter to patients, such as strength and physical
function. Handgrip strength is an easy-to-use screening
instrument for malnutrition and inflammation in patients
on maintenance hemodialysis. Lower hand grip strength
values were independently associated with higher
inflammation and malnutrition among patients on
maintenance hemodialysis.23
MIS.10 The malnutrition-inflammation score (MIS) is a
composite scoring tool that uses 7 components from the
SGA and 3 additional components: body mass index (BMI,
in kg/m2); serum albumin; and total iron–binding capacity
(TIBC). Notably, both BMI and serum albumin are PEW
diagnostic criteria.
Can nephrologists learn from hibernating
bears?
Since muscle loss is prevalent in people with reduced renal
function, nephrologists have long sought ways to prevent
this serious complication. Dr Peter Stenvinkel suggested
that renal researchers take a closer look at a remarkable
natural model of reduced kidney function—the hibernating
black bear.27 Hibernating bears have a 70% reduced
glomerular filtration rate (GRF) and anuria because kidney
filtrate is almost completely resorbed by the body. Following
the winter hibernation, black bears show no signs of
muscle loss even though they did not move, eat, drink, or
urinate for 6 months. On awakening in the spring, the bears
return to near-normal physical function within minutes;
mobility, strength and endurance are intact.27 By contrast,
prolonged bed rest in humans causes profound loss of
muscle strength and function. Why are hibernating bears
so different from bedridden humans? Two features of
bear metabolism explain why there is little or no rise
in blood urea nitrogen (azotemia) and minimal loss of
muscle (sarcopenia) during hibernation: (1) nitrogenous
waste levels are very low because the bear primarily
metabolizes fat, and (2) the majority of urea that is
generated is recycled back into protein, thus bears are
protected from muscle loss.
Further studies are needed to reveal the regulatory
mechanisms responsible for the metabolic switches that
protect hibernating bears from azotemia and sarcopenia,
and to determine if such insights can benefit people
with CKD.
How is your appetite? Dr Carrero explained that
asking the dialysis patient ‘How is your appetite?’
actually has predictive value. For patients who report
a poor appetite, the survival rate is significantly worse
than for patients who report having a good appetite.24
Assessment Tools
SGA.25 The 7-point Subjective Global Assessment
(SGA) tool is recognized to distinguish different degrees
of PEW associated with increasing risks of mortality
in chronic hemodialysis patients.26 With this scoring
system, 7=normal nutritional status, and 1=severe PEW.
Dr Rafael Perez-Carillo (Panama), Dr Georgi Abraham (India), and
Dr Takefumi Mori (Japan)
6
Nutritional management for CKD
Dr Allison Steiber summarized, “Research results, though
limited, have shown vegetarian diets to be safe and
without negative impact on nutritional status of people
with CKD.”
Nutritional needs of renal patients
Dr Kalantar-Zadeh specifically addressed protein needs of
patients with kidney disease. Before dialysis, people with
poor kidney function are advised to reduce protein intake
to avoid over-working the impaired kidney. With advancing
failure and the use of dialysis, higher levels of protein and
other calories are needed to overcome shortfalls driven
by catabolic disease and by dialysis-related losses. He
cited the “magic numbers” recommended for protein
intake as 0.6-0.8 g protein/kg of body weight (BW)/day for
patients not on dialysis and more than 1.2 g/kg BW/day
for those on dialysis.
What is a renal diet?
Dr Alison Steiber noted that the diet for people
with CKD is one the most restrictive for any patient
group, including guidelines that contradict current
recommendations for healthy eating.28 Kidney patients
are intolerant of high fluid volume, and they must also
limit intake of electrolytes such as phosphorus,
potassium, sodium, and calcium. The typical CKD
diet is low in certain fruits and vegetables due to high
potassium content, low in whole grains due to high
phosphorus, and low in dairy due to high phosphorus
and calcium. Such a diet is deficient in micronutrients
and low in fiber.
“Magic numbers” for protein intake by
people with renal disease are:
• 0.6-0.8 g/kg /day for non-dialyzed patients
• > 1.2 g/kg /day for patients on dialysis
Dr Daniel Teta
(Switzerland) advised,
“We need to close the
nutrition gap in order to
prevent PEW.” For CKD
patients on dialysis,
he recommended an
energy intake of 30-35
kcal/kg BW/day with >
1.2 g protein/kg ideal
body weight (IBW)/
day. He advised that
some micronutrient
Dr Daniel Teta, University Hospital
supplementation may be
of Lausanne, Switzerland
required, including the B
vitamins, vitamins C and E, and trace elements such as
zinc and selenium.
The CKD diet is one the most restrictive
for any patient group, including limits that
contradict current recommendations for
healthy eating.
Despite the importance of dietary compliance, a recent
US study found that 88% of CKD patients who started
on hemodialysis had never seen a dietitian;29 however,
those who had seen a dietitian were less likely to have
low serum albumin levels and less likely to die within the
first year of dialysis.29
Given the risk for cardiovascular disease in people with
CKD, a diet containing heart-healthy fats is particularly
important. For maintaining heart health, the American
Heart Association recommends fats derived from foods
rich in the essential fatty acids: linoleic acid (omega-6)
and alpha-linolenic acid (omega 3), as found in seeds
and nuts.30
Dr Teta recommended other specific strategies to prevent
or treat PEW:
• Ensure adequacy of dialysis dose, particularly for
unstable patients who are malnourished.
Vegetarian diet: is there a role in CKD?
Vegetarian diets have been used in some cultures for
centuries and are now resurging in Western culture
as a more healthy option. Concerns have been
expressed about vegetarian diets for people with CKD
because some fruits, vegetables and legumes have
high potassium and phosphorus content. On the other
hand, plant-based foods are generally high in fiber and
antioxidants, and lower in saturated fats. In fact, results
of a very recent study showed that plant-based diets
with nuts and olive oil can reduce risk of heart disease
by 30%.31
• Treat metabolic acidosis with bicarbonate to offset
negative effects of uremia on food intake.
• Offer regular nutritional follow-up and dietary
counseling.
• Recommend oral nutrition supplements (ONS) if
spontaneous nutrient intake is low.
• Encourage regular physical activity or formal exercise
sessions to maintain lean body mass.
7
Dr Denis Fouque
(France) discussed
the strategies of giving
supplemental ONS or
intradialytic parenteral
nutrition for patients
on dialysis. With ONS,
study results show
a wide range of
nutritional measures
that can be improved:
energy and protein
intake, serum albumin,
SGA, and quality of life
scores.32, 33 In addition,
a late evening meal or ONS can reduce the length of
nocturnal starvation and the associated breakdown
of endogenous protein and fat stores.34 When enteral
nutrition is not possible, e.g., with swallowing difficulties,
intradialytic parenteral nutrition (glucose + fat emulsions +
amino acids) can be used, as needed, to reach nutritional
objectives.
Dr Fouque used a case study to underscore his
messages on nutrition and kidney disease.
A late evening meal or ONS can reduce
the length of nocturnal starvation and the
associated breakdown of endogenous
protein and fat stores.
Dr Denis Fouque, University Claude
Bernard, Lyon, France
Question: Why do hemodialysis patients lose weight, especially lean body mass, and how can this
risk be treated?
Case example: A 48-year-old man has been on hemodialysis (3-times per week) for 2 years due to kidney
damage from high blood pressure and nephroangiosclerosis. Laboratory findings showed that his serum albumin
was 3.9 g/dL, serum creatinine was 11 mg/dL, and urea was 150 mg/dL. Over the past 9 months, the patient
has lost 15% of body weight (down to 65 kg) and now has a body mass index (BMI) of 22.5 kg/m2. His SGA
nutrition score is 6 on a 7-point scale, and he complains of appetite loss, nausea, and vomiting.
Answer: This patient is experiencing anorexia and may be showing early evidence of protein-energy wasting
(PEW). It is possible that the patient may have gastrointestinal dysfunction, but his poor appetite and wasting
are likely resulting from poor kidney function. As kidney function declines, urea and other waste products build
up in the blood. This uremic condition, in turn, increases degradation of muscle proteins (elevated creatinine),
hypoalbuminemia, and anorexia. The dialysis procedure itself also contributes to PEW; dialysis removes amino
acids from the blood and can also cause inflammation. With depletion of the amino acid pool, muscle is broken
down to replete the pool.
Intervention 1 and results: Order gastroscopy to review gastrointestinal function, and order a 3-day food
recall to assess his level of spontaneous intake. Gastroscopy findings were normal. Based on the food recall,
the patient consumed only 25 kcal/kg/day of energy (including 0.9 g/kg/day protein) on non-dialysis days, and
22 kcal/kg/day of energy (including 0.7 g/kg/day protein) on dialysis days. Over the next 3 months, weight loss
continued (65 kg), and BMI fell further (20.8 kg/m2), while creatinine (9.0 mg/dL) and urea (100 mg/dL) levels were
slightly lowered.
Intervention 2 and results: Recommend increasing food intake (more small meals per day; snack during
dialysis; increased energy density of preferred foods) and prescribe 2 ONS daily after main meals (targeting a
total of 35 kcal/kg BW/day including 1.2 g/kg/day protein). Recheck nutrition parameters and kidney function
tests in a month. Weight loss continued (58kg), as did BMI (20.0 kg/m2) and serum albumin lowering (3.5 g/dL).
Intervention 3 and results: Because the patient was unable to follow your general nutritional advice, order
addition of at least 2 kidney-disease-specific ONS for patients on dialysis (high energy, high protein, low
potassium, low phosphorus) each day, possibly delivered as small servings at 3 to 5 snacks. Recheck nutritional
and kidney parameters in one month. After a month, you finally see modest evidence of weight gain (58.5 kg)
and increasing BMI (20.5 kg/m2) and serum albumin (3.7 g/dL). Recheck nutritional status regularly.
Take-home messages: PEW advances insidiously over time, so it is important to be aware of risk and
advise frequent check-ups. Dietary support should be enforced, and oral nutrition is preferable over parenteral
whenever possible. Increasing dietary intake can correct PEW for many patients.
8
Let them eat during dialysis: an opinion
from Dr Kalantar-Zadeh35
ONS: an intervention that
improves survival
In-center high-protein meals or oral nutritional
supplements during hemodialysis is a new
but rational and patient-friendly strategy to
prevent or treat PEW, despite concerns such
as infection control and hygiene, dialysis staff
burden, and phosphorus control.
New evidence shows marked improvement in survival for
hemodialysis patients when they consumed oral nutrition
supplements. Clinicians have known for some time that
oral supplements can improve nutritional markers38 and
SGA scores39 in dialysis patients, yet evidence linking ONS
to improved survival was lacking.
If severe hypoalbuminemia (<3.0 g/dL) cannot
be reversed by oral interventions, then
parenteral interventions such as intradialytic
parenteral nutrition can be considered.
Given the fact that meals and supplements
during hemodialysis represent a very small
fraction of the total cost of dialysis, this strategy
also makes good economic sense.
Results of a new study by Lacson and colleagues
showed that consuming ONS during dialysis was indeed
associated with increased survival.40 In an ‘as-treated’
analysis, the research team found that hemodialysis
patients had a 34% reduced risk for one-year mortality
when they regularly consumed ONS during dialysis visits
over a one-year interval.
ONS consumption during dialysis over a 1
year interval was associated with a 34%
reduced risk of mortality.
Nutritional considerations for patients
with diabetic nephropathy
Reduction of protein intake to 0.8–1.0 g/kg body
weight/day in earlier stages of CKD and lowering
to 0.8 g/kg body weight/day in later stages of CKD
may help lower urine albumin excretion and slow
the decrease in glomerular filtration. However, it
is essential to ensure adequate energy intake.
Malnutrition and decreased muscle strength can
result from reduced energy intake and low-protein
diets.
1.0
0.8
0.6
Survival
Dr Rosa Sánchez
Hernández (Spain)
began her presentation
by noting that risk for
kidney disease is 4
times higher in people
with type 2 diabetes
compared to those
without.36 Nutritional
recommendations
vary according to CKD
severity.37 For people
Dr Rosa Sánchez Hernández,
with diabetes who are
Segovia General Hospital, Spain
overweight or obese,
weight loss is recommended; either low­
carbohydrate, low-fat calorie-restricted, or
Mediterranean diets may be effective.
1:1 ‘As-treated’ matched cohort
0.4
Without Nutritional Supplementation
With Nutritional Supplementation
0.2
0.0
0
60
120
180
240
300
Time (days) to death
360
420
Debate: Is there a role for a low­
protein diet in non-dialyzed CKD
stages 3 to 5?
Drs Denis Fouque and Alp Ikizler genially debated the
“pros” and “cons” of a low-protein diet in people with
kidney disease. On the ”pro” side, Dr Fouque reviewed a
longstanding and traditional history of limiting protein intake
to slow the worsening of kidney function. This practice is
supported in terms of metabolic parameters, i.e. lowered
acidosis and phosphorus levels and improved lipid profiles.
However, results of a recent meta-analysis (n=2,000
subjects) showed that reducing protein intake in patients
significantly lowers the occurrence of renal death by 32%,
as compared with higher or unrestricted protein intake.41
9
On the “con” side, Dr Ikizler expressed concern over
limited findings from a low-protein diet in full-scale
clinical studies. He questioned why overall effects
of a low- protein diet on kidney function were less
than expected compared to strong animal data and
early studies. According to Dr Ikizler, further well­
controlled studies are needed to show that metabolic
benefits of the low-protein diet translate into delaying
CKD progression, especially studies using hard
clinical outcomes such as time to initiation of dialysis,
cardiovascular events, and survival. On the other
hand, Dr Ikizler reported that evidence of harm from a
low-protein diet does not exist.
A middle-ground strategy seems rational—a protein­
restricted diet that meets individualized needs and is
carefully monitored to ensure adequate caloric intake
and prevention of PEW in each person. For a stage
3-5 CKD patient who is not dialysis-dependent, the
recommendation is to consume 0.6 to 0.8 g protein/
kg/day for most patients.20 If other disease is present,
protein needs may be higher, so protein intake up to
1.0 g/kg/day is justified.20
An algorithm for nutritional management of
CKD patients.
Periodic nutritional and dietary counseling
• Dry weight, lab values (serum albumin) & scores
(SGA, MIS)
• Dietary counseling and high protein meals during
hemodialysis
An algorithm for
CKD nutrition
Dr Kalantar-Zadeh (USA) and colleagues created
an algorithm for the nutritional management of non­
dialyzed and dialyzed CKD patients.18 He described the
importance of periodic assessment and counseling of
patients, and discussed how to use renal-specific oral
nutrition supplements (ONS) as a first choice for patients
at nutritional risk. Specifically, this management algorithm
recommends ONS for CKD patients with any one of these
indicators:
• serum albumin < 4.0 g/dL
• poor appetite or poor oral intake
• unintentional weight loss (dry weight)
• MIS score ≥ 5 or SGA score in malnutrition range
(B or C).
Exercise: does it matter?
Physical activity is very low among patients new to
dialysis, and it often declines with duration of dialysis.42
In advancing CKD, low physical functioning is associated
with poor outcomes, such as frailty and death. According
to Dr Alp Ikizler, exercise is an anabolic intervention that
represents an attractive strategy to improve muscle mass.
However, studies have not yet shown remarkable benefits
of exercise alone on body composition or physical
functioning over the long-term in CKD dialysis patients.
Indications for nutritional intervention
•
•
•
•
Poor appetite and/or poor oral intake
Unintentional loss of dry weight
Serum albumin level < 4.0g/dL
MIS ≥ 5 or SGA in malnourished range
Start oral nutritional supplementation 1-2 servings/day
• Non-dialyzed patients: Moderately low protein +/- amino acid or keto-analogs
• Dialysis patients: Moderate to high protein supplements, including during dialysis Rx
Monthly assessment
Improvement
• Monitior nutritional status for changes
in appetite, food intake, weight status,
serum albumin level and MIS/SGA
No improvement
or deterioration
Maintenance oral therapy
Adjunct pharmacologic
therapies
Intensified therapy or
additional interventions
• If serum albium reaches 4.0 g/
dL, continue meals and/or oral
supplements on dialysis
• Consider liquid oral supplement
with pill intake to reduce water
•
•
•
•
Appetite stimulators
Anti-depressant
Anti-inflammatory and/or anti-oxidative
Anabolic and/or muscle enhancing
MIS=Malnutrition inflammation; SGA=Subjective Global Assessment.
10
• Increase quality of oral therapy
• Enteral feeding
• Parenteral feeding
(if albumin <3.0g/dL)
Global
perspectives on
kidney nutrition
Because kidney care
varies considerably
around the world, the
Conference provided
country-specific
snapshots of nutrition
problems and solutions in
kidney care.
Dr Nikolina Basic Jukic, University Hospital Zagreb, Croatia, stated,
“All dialysis patients in our center receive ONS to prevent PEW.”
India. Dr Georgi
Abraham explained that
end-stage renal disease
develops in more than
200 people per million
Dr Georgi Abraham, Madras Medical
per year in India43 or at
Mission Hospital, Chennai, India
least 200,000 individuals
in a population of 1 billion. Yet there are only 1000 kidney
specialists to care for them. Dr Abraham reported that
many end-stage renal patients die within months of
diagnosis because they have no nephrologist and cannot
afford treatment, especially dialysis. Use of renal-specific
nutritional supplements to increase compliance with
the low-protein diet can help improve nutritional status,
prolong survival, and contain costs.
maintained at about 50% of their usual dialysis dose.
Individuals who were on peritoneal dialysis fared better
in the post-earthquake days because they self-managed
care. As a result, use of peritoneal dialysis is now
being expanded in Japan. Also, where food shortages
existed, the widely used food condiment mayonnaise
was identified as a perfect emergency food for kidney
patients; mayonnaise is high in calories and low in
protein, potassium, and phosphorus.
Croatia. Dr Nikolina Basic Jukic, Vice-President of the
Croatian Society of Nephrology, discussed Croatia’s
unique strategy for managing patients with renal
disease—quick transition to transplant. Of patients with
end-stage renal disease, a striking 35% are given kidney
transplants. This remarkable transplant rate represents
one of the highest in the world. Patients remaining on
dialysis are typically older and are not good candidates
for the transplant procedure.
Dr. Basic stated that all dialysis patients in her center
receive ONS to prevent PEW.
Brazil. According to Dr Miguel Riella, almost 100,000
Brazilians are now on dialysis. While these patients could
clearly benefit from renal-specific nutritional supplements,
few can afford them, and the government health care
does not pay. He sees greater access to nutritional
supplements as a promising approach to improving
kidney care in Brazil.
Panama. Dr Rafael Perez-Carillo stated that the
government health system only pays for kidney­
specific nutritional supplements if patients already have
evidence of malnutrition. Such a limitation may represent
missed opportunities to save money and lives by using
nutritional supplements to help prevent PEW.
Japan. Dr Takefumi Mori described lessons learned by
nephrologists following Japan’s 2012 earthquake and
tsunami. Because of shortages in hemodialysis supplies
and equipment, many hemodialysis patients were
Meeting faculty
Name
Country Name
Georgi Abraham, MD, PhD
India
Rosa Sánchez Hernández, MD, PhD Spain
Juan Jesús Carrero, MD, PhD
Sweden
Alison L. Steiber, PhD, RD, LD
USA
Denis Fouque, MD, PhD
France
Peter Stenvinkel, MD, PhD
Sweden
Alp Ikizler, MD, PhD
USA
Daniel Teta, MD, PhD
Switzerland
Kamyar Kalantar-Zadeh, MD, MPH, PhD USA
11
Country
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