Sarcopenia among the Elderly Population: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

Plant-based alternative proteins-are they nutritionally more advantageous?

BACKGROUND

The transition towards sustainable nutrition as well as the exploration of alternative sources of protein have been at the forefront of thinking in the 21st century. However, further research is required to ascertain if a diet composed of alternative plant-based proteins has similar nutritional advantages to a plant-based diet. This study aims to model the replacement of a diet consisting of animal-based proteins with plant-based alternatives (PBA), in a group of Asians.

METHODS

A 4-day food record was collected from 50 individuals residing in Singapore and nutrient profiles were generated for each individual. Food records were analysed, and meat, dairy, and seafood ingredients were substituted gram-for-gram with their PBA. The original and replaced nutrient profiles were compared against each other and the differences in macro and micronutrients were analysed.

RESULTS

A significant increase in carbohydrates, dietary fibre, as well as in micronutrients such as sodium and calcium was observed. Conversely, there was a significant decreased intake in overall energy, protein and fat (p < 0.005).

CONCLUSIONS

The significant nutritional impact of substituting animal-based proteins for PBA may present benefits for bone health and individuals on a caloric restriction diet. However, higher sodium levels may be undesirable for individuals with cardiovascular conditions and hypertension, and the low bioavailability of iron in plant-based sources may present issues for iron deficient populations. Bearing some of these key findings in mind, researchers and manufacturers need to consider these when developing alternative protein products to meet consumer demands for palatable and nutritious plant-based products.

Depression and risk of sarcopenia: a national cohort and Mendelian randomization study

Background

Depression and the increased risk of sarcopenia are prevalent among the elderly population. However, the causal associations between these factors remain unclear. To investigate the potential association between depression and the risk of sarcopenia in older adults, this study was performed.

Methods

In the baseline survey, a total of 14,258 individuals aged 40 and above from the China Health and Retirement Longitudinal Study (2015) participated. We initially described the baseline prevalence of the disease. Then, logistic regression and restricted cubic spline (RCS) regression were conducted to assess the relationship between depression and sarcopenia. Subgroup analysis was performed to validate the robustness of the findings. Additionally, we conducted Mendelian randomization analysis using the inverse variance weighting estimator to assess the causal relationship between depression and sarcopenia. Furthermore, we adopted six methods, including MR-Egger, simple median, weighted median, maximum likelihood, robust adjusted profile score (RAPS), and MR Pleiotropy Residual Sum and Outlier (MR-PRESSO), for sensitivity analyses.

Results

Depression patients exhibited higher risks of sarcopenia in all five models adjusting for different covariates (P < 0.05). The RCS analysis demonstrated a linear relationship between depression and sarcopenia (P < 0.05). In the subgroup analysis, increased risk was observed among participants aged 60-70, married or cohabiting individuals, non-smokers, non-drinkers, those with less than 8 h of sleep, BMI below 24, and individuals with hypertension (all P < 0.05). Mendelian randomization results revealed that genetically proxied depression led to a reduction in appendicular skeletal muscle mass (all P < 0.05).

Conclusion

Our study provides observational and causal evidences that depression can lead to sarcopenia. This finding emphasizes the importance of timely identification and management of depression, as well as implementing targeted educational programs as part of comprehensive strategies to prevent sarcopenia.

The Impact of Whey Protein Supplementation on Sarcopenia Progression among the Elderly: A Systematic Review and Meta-Analysis

We conducted a systematic literature review and meta-analysis to investigate the role of whey protein supplementation in the functioning of the elderly with sarcopenia. The aim was to investigate the available scientific evidence and determine the best recommendations with respect to whey protein supplementation in sarcopenic patients. Methods: Databases, including CINAHL, Embase PubMed, and Web of Science, were searched from database inception until 31 December 2022 for randomised controlled trials (RCTs) comparing the efficacy of whey protein supplementation in the elderly with sarcopenia. Data on study design, risk of bias, patient, illness, and treatment characteristics from each study were independently extracted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA). The tool "assessing risk of bias" from the Cochrane Handbook was used to evaluate the quality of the included papers. Results: The search identified 629 records; 590 articles were excluded as duplicates or after evaluation at the title or abstract level. Out of 39 full-text articles that were reviewed, 29 were excluded for not fulfilling the inclusion criteria. There is some evidence that whey protein supplementation combined with age-appropriate physical exercise might improve muscle mass and lower limb function in the elderly with sarcopenia. The present meta-analysis demonstrated overall that whey supplementation does not improve any of the tested sarcopenia-linked parameters. However, we found that study duration (weeks) and age significantly affect the handgrip strength rate and the chair and stand test rate, respectively, so consideration should be given to oral supplementation combined with the age of participants and an appropriate physical activity as a form of sarcopenia prevention in the high-risk group.

Chair-Stand Exercise Improves Sarcopenia in Rehabilitation Patients after Stroke

Currently, there is a lack of evidence to show that exercise therapy improves sarcopenia in older patients in clinical practice. We therefore conducted a retrospective cohort study to clarify the effects of chair-stand exercise on improving sarcopenia among patients diagnosed with sarcopenia undergoing convalescent rehabilitation after stroke. According to the latest Asian criteria, sarcopenia was diagnosed when both skeletal muscle mass index (SMI) and handgrip strength (HGS) were low. Patients were asked to perform a repeated chair-stand exercise as whole-body resistance training, in addition to the rehabilitation program. Outcomes included sarcopenia rates, SMI, HGS, and physical function at hospital discharge. Multivariate analyses were used to examine whether the frequency of daily chair-stand exercise was independently associated with the outcomes after adjustment for potential confounders. After enrollment, 302 patients with sarcopenia (mean age: 78.6 years; 46.4% male) were analyzed. Overall, sarcopenia prevalence decreased by 21.9%, from 100% at admission to 78.1% at discharge. Multivariate analyses showed that the frequency of the exercise was significantly associated with the presence of sarcopenia (odds ratio: 0.986, p = 0.010), SMI (β = 0.181, p < 0.001), and HGS (β = 0.101, p = 0.032) at discharge, respectively. The chair-standing exercise was effective in improving sarcopenia in these patients.

Effects of branched-chain amino acid-rich supplementation on EWGSOP2 criteria for sarcopenia in older adults: a systematic review and meta-analysis

PURPOSE

According to criteria recommended by the European Working Group on Sarcopenia in Older People 2 (EWGSOP2), we analyzed the effects of branched-chain amino acid (BCAA)-rich supplements on muscle strength, muscle mass, and physical performance in older people.

METHODS

We searched PubMed, Embase, Cochrane Library, and CINAHL from inception until March 2021. Randomized controlled trials that examined the effect of BCAA-rich supplements on older people were included. Random-effects meta-analyses and sensitivity analyses were performed. Subgroup analyses were stratified by participant and supplementation characteristics. Meta-regression analyses were performed to examine the effect of continuous variables.

RESULTS

Thirty-five studies were included in this meta-analysis. Quality assessment revealed that 14 of 35 RCTs had some potential bias. The overall standardized mean difference (SMD) in muscle strength, muscle mass, and physical performance between the supplement and control groups was 0.35 (95% CI = [0.15, 0.55], P = 0.0007), 0.25 (95% CI = [0.10, 0.40], P = 0.0008), and 0.29 (95% CI = [0.00, 0.57], P = 0.05), respectively. Subgroup analysis revealed that essential amino acid supplementation improved handgrip strength more significantly than whey protein supplementation in older people. Meta-regression analysis revealed a significant linear relationship between improvements in handgrip strength and body mass index.

CONCLUSIONS

BCAA-rich supplementation by older people may have beneficial effects on muscle mass and strength. However, the included studies had high heterogeneity, and the results must be interpreted with caution.

PROSPERO REGISTRATION NUMBER

CRD42020206674.

Nutrition in Patients with Type 2 Diabetes: Present Knowledge and Remaining Challenges

Unhealthy behaviours, including diet and physical activity, coupled with genetic predisposition, drive type 2 diabetes (T2D) occurrence and severity; the present review aims to summarise the most recent nutritional approaches in T2D, outlining unmet needs. Guidelines consistently suggest reducing energy intake to counteract the obesity epidemic, frequently resulting in sarcopenic obesity, a condition associated with poorer metabolic control and cardiovascular disease. Various dietary approaches have been proposed with largely similar results, with a preference for the Mediterranean diet and the best practice being the diet that patients feel confident of maintaining in the long term based on individual preferences. Patient adherence is indeed the pivotal factor for weight loss and long-term maintenance, requiring intensive lifestyle intervention. The consumption of nutritional supplements continues to increase even if international societies do not support their systematic use. Inositols and vitamin D supplementation, as well as micronutrients (zinc, chromium, magnesium) and pre/probiotics, result in modest improvement in insulin sensitivity, but their use is not systematically suggested. To reach the desired goals, patients should be actively involved in the collaborative development of a personalised meal plan associated with habitual physical activity, aiming at normal body weight and metabolic control.