Heart failure (HF) has a significant impact on patient muscle function and body composition and muscle loss is a strong predictor of frailty and reduced survival in patients with HF.
Nutritional recommendations for an older adult (>65 years) population propose an increase in daily protein intake, to 1.2–1.5 g/kg/day, preferably of high-quality protein containing large amounts of essential amino acids (EAAs) such as leucine.
The use of whey protein isolate (WPI), alongside exercise, has been shown to lead to increased muscle protein synthesis and skeletal muscle mass, as well as enhanced exercise recovery. However, many HF patients are unable to exercise due to physical restrictions.
Therefore, this study aimed to evaluate whether supplementation with WPI, compared to placebo, promotes changes in body composition, especially muscle mass, as well as skeletal muscle strength, in patients with chronic HF.
The 12-week single-blind, randomised, placebo-controlled clinical trial involving 25 patients (15 in WPI and 10 in placebo group) concluded that WPI supplementation promoted an improvement of body composition, evidenced by an increase in skeletal muscle mass and a decrease in body fat.
The team conclude: "WPI supplementation may be useful for these patients, who are frequently unable to exercise or are limited in their access to supervised exercise programs. The current results may help change the paradigm of the need for exercise during WPI supplementation, which is particularly useful in the specific population of HF patients."
The study
Participants were randomly allocated to receive supplementation with WPI (30 g/day [27 g protein; 120 kcal/serving]) or placebo (maltodextrin, 30 g/day [30 g carbohydrates; 120 kcal/ serving]). Patients were instructed to consume the supplements once a day for 12 weeks.
All patients had fasting blood biochemical evaluation, handgrip-strength assessment, and anthropometric and body composition evaluations before and after 12 weeks of supplementation.
Systolic blood pressure (SBP) and diastolic blood pressure (DBP) were evaluated using a sphygmomanometer. Blood sampling was performed to measure serum urea, creatinine, glycemia, triglycerides, total cholesterol, and high-density lipoprotein cholesterol.
The anthropometric evaluation included body weight and height, waist, and hip measurements, as well as body mass index (BMI) calculation. Sarcopenia was evaluated by calculating the skeletal muscle index (SMI).
The assessment of the patients’ dietary intake was performed by completing a 24-h dietary recall.
Resulting data revealed that, after 12 weeks of WPI supplementation, waist circumference, fat mass, and % fat mass decreased, while skeletal muscle mass and skeletal muscle index increased compared to placebo. Handgrip strength also showed a tendency towards increase (mean 25.7 kgf before and 28.1 kgf after WPI supplementation, p = 0.05) but this wasn't significant. Among patients who received the placebo, no significant change was observed.
Regarding dietary composition, the daily protein intake per kilogram of body weight was found to be below appropriate levels for patients with HF at baseline, even though the percentage of protein intake was within normal limits. The authors state that this reinforces the importance of routine dietary assessment of patients with HF, as nutritional deficits may go unnoticed.
The authors conclude: "With WPI, there was a significant increase in skeletal muscle mass (0.6 ± 0.7 kg) after 12 weeks. Prior studies had described the effects of WPI on muscle mass gain, but with associated exercise training.
"The current results are promising as they show results in terms of muscle gain irrespective of the addition of exercise, which may be viewed as a reality in many settings in which cardiac rehabilitation or other methods of supervised training are not available. It is worth noting that WPI did not result in a significant increase in muscle strength, measured by the handgrip."
They note a main limitation of the study is the small sample size and relatively high dropout rate, especially in the placebo group.
Source: Nutrients
https://doi.org/10.3390/nu15102320 (registering DOI)
"Effects of Whey Protein Isolate on Body Composition, Muscle Mass, and Strength of Chronic Heart Failure Patients: A Randomized Clinical Trial"
Authors: dos Santos, E.M.; Moreira, A.S.B.; Huguenin, G.V.B.; Tibiriça, E.; De Lorenzo, A.