Nutritional interventions to improve muscle mass, muscle strength, and physical performance in older people: an umbrella review of systematic reviews and meta-analyses

Lack of evidence for Omega-3 fatty acid supplementation in enhancing lean mass, muscle strength, and physical function in healthy adults and clinical populations: An overview of reviews

BACKGROUND & AIMS

N-3 (omega-3) polyunsaturated fatty acids (n-3-PUFA) have been hypothesized to enhance/maintain skeletal muscle mass, strength, and physical function. We conducted an overview of reviews of n-3 fatty acid monotherapy supplementation and examined whether the evidence supports the effects in healthy young and old adults and clinical populations.

METHODS

In line with the PRISMA guidelines, a widely accepted framework for conducting and reporting systematic reviews, we conducted a comprehensive search for systematic reviews (OVID, Embase, Web of Science, SPORTDiscus) reporting the effect of n-3 fatty acid supplementation in our target populations. To ensure the reliability and validity of our findings, the methodological quality of the reviews was assessed using A Measurement Tool to Assess Systematic Reviews (AMSTAR) 1, a validated tool for appraising the methodological quality of systematic reviews.

RESULTS

Thirty-three systematic reviews met our inclusion criteria: 19 non-oncologic, 11 oncologic, and 3 mixed. In non-oncologic populations, 4 out of 16 reviews showed some evidence that n-3-PUFA supplementation benefitted lean mass, with 3 reviews focusing on older populations. For strength, 1 out of 14 reviews found sufficient evidence in favor, while 3 others reported some evidence of n-3-PUFA ingestion. For physical function, 1 out of 15 reviews found sufficient evidence, and 3 reported some evidence favoring n-3-PUFA use. In oncologic participants, only 1 out of 13 reviews found sufficient evidence that n-3-PUFA improved lean mass. No reviews found sufficient evidence for strength or physical function improvements.

CONCLUSIONS

Our analysis indicates limited evidence supporting the effectiveness of n-3-PUFA supplementation in both younger and older healthy adults, as well as clinical populations including oncologic patients, to improve or prevent loss of lean mass. Most systematic reviews concluded that n-3-PUFA supplementation did not significantly affect strength, or studies were inconclusive, and there was no consistent impact of n-3-PUFA supplementation on functional outcome measures. These findings underscore the need for further research to better understand the role of n-3-PUFA in muscle health and to guide clinical practice. Our analysis does not support n-3-PUFA monotherapy for lean mass gain/retention enhancing strength or function in healthy young and older persons, and oncologic populations.

Age-associated changes in the heart: implications for COVID-19 therapies

Cardiac aging involves progressive structural, functional, cellular, and molecular changes that impair heart function. This review explores key mechanisms, including oxidative stress, mitochondrial dysfunction, impaired autophagy, and chronic low-grade inflammation. Excess reactive oxygen species (ROS) damage heart muscle cells, contributing to fibrosis and cellular aging. Mitochondrial dysfunction reduces energy production and increases oxidative stress, accelerating cardiac decline. Impaired autophagy limits the removal of damaged proteins and organelles, while inflammation activates signaling molecules that drive tissue remodeling. Gender differences reveal estrogen's protective role in premenopausal women, with men showing greater susceptibility to heart muscle dysfunction and injury. After menopause, women lose this hormonal protection, increasing their risk of cardiovascular conditions. Ethnic disparities, particularly among underserved minority populations, emphasize how social factors such as access to care, environment, and chronic stress contribute to worsening cardiovascular outcomes. The coronavirus disease pandemic has introduced further challenges by increasing the incidence of heart damage through inflammation, blood clots, and long-term heart failure, especially in older adults with existing metabolic conditions like diabetes and high blood pressure. The virus's interaction with receptors on heart and blood vessel cells, along with a weakened immune response in older adults, intensifies cardiac aging. Emerging therapies include delivery of therapeutic extracellular vesicles, immune cell modulation, and treatments targeting mitochondria. In addition, lifestyle strategies such as regular physical activity, nutritional improvements, and stress reduction remain vital to maintaining cardiac health. Understanding how these biological and social factors intersect is critical to developing targeted strategies that promote healthy aging of the heart.

The use of protein supplements in children with cerebral palsy: A scoping literature review

The aim of this scoping review was to examine the literature regarding the use of protein supplements to improve macroscopic muscle properties in a pediatric population in general, and more specifically in children with cerebral palsy. Based on our prospectively registered protocol (https://doi.org/10.17605/OSF.IO/8DM9G), a systematic literature search was performed in five databases and two clinical registers. Studies were selected by two independent reviewers using predefined selection criteria, and data were summarized using a data extraction form. A broader search on adults with cerebral palsy and the general pediatric population was considered to be relevant due to the limited number of studies conducted in children with cerebral palsy. After deduplication, 5207 records were identified and screened. A total of 18 publications were included in the current review. Two studies were performed in individuals with cerebral palsy, eight in healthy children, two in children with respiratory problems, one in critically ill children, one in children with end-stage liver disease, one in children and adolescents undergoing treatment for a pediatric malignancy, one in children with Pompe disease and two in children with Duchenne muscular dystrophy. The different muscle parameters reported were muscle volume, muscle mass, fat-free mass and fat-free mass index, lean body mass and lean body mass percentage, arm muscle area and muscle cross-sectional area of the arm, thigh and calf. The heterogeneity of the included studies and their moderate quality level made it difficult to draw solid overall conclusions. More research is needed on the use of protein supplements in children with cerebral palsy. However, supplementation with branched-chain amino acids, in particular leucine, might be promising.

The Effects of Structured Prehabilitation on Postoperative Outcomes Following Total Hip and Total Knee Arthroplasty: An Overview of Systematic Reviews and Meta-analyses of Randomized Controlled Trials

OBJECTIVE: To evaluate the effects of prehabilitation on postoperative outcomes following total hip arthroplasty (THA) and total knee arthroplasty (TKA). DESIGN: Overview of systematic reviews and meta-analyses of randomized controlled trials. LITERATURE SEARCH: Guided by the PRIOR (Preferred Reporting Items for Overviews of Reviews) statement, a systematic search of MEDLINE, Embase, Web of Science, and Cochrane CENTRAL (Cochrane Register of Controlled Trials) was conducted using the following overarching topics: hip, knee, arthroplasty, and prehabilitation. STUDY SELECTION CRITERIA: Systematic reviews, meta-analyses, or meta-regressions of randomized controlled trials that investigated how postoperative outcomes differed between patients who underwent primary THA or TKA and engaged in a structured prehabilitation program (exclusively resistance training [RT]-focused or multimodal with RT) or non-RT exercising controls. DATA SYNTHESIS: THA and TKA data were analyzed separately, with results delineated based on RT components (ie, weekly sets, frequency, and load) and the follow-up period (ie, short term: 1-3 years; midterm: 5-7 years; and long term: ≥10 years). RESULTS: Three systematic reviews and 21 meta-analyses (19 THA randomized controlled trials, 1110 THA patients; 46 TKA randomized controlled trials, 3362 TKA patients) ranging from critically low- to moderate-quality evidence were included. Prehabilitation was favorable for reducing the rate of complications, improving strength, objective function, quality of life, and self-reported function in patients undergoing THA and TKA. Effects were attenuated over time and were generally confined to the first 6 months. RT volume did not affect postoperative outcomes in 2 meta-regressions. No analyses evaluated how the manipulation of RT components affected postoperative outcomes. CONCLUSION: Prehabilitation reduced complication rates and improved objective and subjective postoperative outcomes following THA and TKA, with effects generally confined to the first 6 months. J Orthop Sports Phys Ther 2025;55(5):1-22. Epub 3 April 2025. doi:10.2519/jospt.2025.13075.

Sarcopenia in Peritoneal Dialysis: Prevalence, Pathophysiology, and Management Strategies

Sarcopenia, defined as the loss of skeletal muscle mass, strength, and function, is a significant complication in patients with chronic kidney disease, particularly those undergoing peritoneal dialysis (PD). This review explores the prevalence, pathophysiology, diagnostic challenges, and management strategies of sarcopenia in the PD population. The multifactorial etiology of sarcopenia in PD, including protein-energy wasting, chronic inflammation, insulin resistance, and hormonal imbalances, underscores the complexity of its management. The prevalence of sarcopenia in patients treated with PD is influenced by age, duration of dialysis, and comorbid conditions, presenting a considerable variation across studies due to differing diagnostic criteria. Diagnostic challenges arise from fluid overload and the PD process, affecting the accuracy of muscle mass measurements. Intervention strategies focusing on nutritional supplementation and physical exercise have shown promise; however, the need for PD-specific diagnostic criteria and treatment protocols remains. This review highlights the critical effect of sarcopenia on functional status and survival in patients treated with PD, emphasizing the importance of addressing this condition to improve patient outcomes. Future directions call for comprehensive, longitudinal studies to better understand sarcopenia's progression in patients treated with PD and the development of tailored interventions.

Construction and Evaluation of a Novel Nomogram for Predicting Dual Dimensional Frailty in Older Maintenance Haemodialysis Patients

OBJECTIVE

To construct and evaluate a novel nomogram for predicting the risk of dual dimensional frailty (comorbidity between physical frailty and social frailty) in older maintenance haemodialysis.

METHODS

A cross-sectional investigation was conducted. A total of 386 older MHD patients were recruited between September and December 2024 from four haemodialysis centres in four tertiary hospitals in Sichuan Province, China. LASSO regression and binary logistic regression were employed to determine the predictors of dual dimensional frailty. The prediction performance of the model was evaluated by discrimination and calibration. The decision curve was utilised to estimate the clinical utility. Internal validation with 1000 bootstrap samples was conducted to minimise overfitting.

RESULTS

In the overall sample (386 cases), a total of 92 (23.8%) of patients exhibited dual dimensional frailty. Five relevant predictors, including physical activity, self-perceived health status, ADL impairment, malnutrition, and self-perceptions of aging, were identified for constructing the nomogram. Internal validation indicated excellent discriminatory power and calibration of the model, while the clinical decision curve demonstrated its remarkable clinical utility.

CONCLUSIONS

The novel nomogram constructed in this study holds promise for aiding healthcare professionals in identifying physical and social frailty risks among older patients on maintenance haemodialysis, potentially informing early and targeted interventions.

RELEVANCE TO CLINICAL PRACTICE

This nomogram enables nurses to efficiently stratify dual-dimensional frailty risk during routine assessments, facilitating early identification of high-risk patients. Its visual output can guide tailored interventions, such as exercise programmes, nutritional support, and counselling, while optimising resource allocation.

PATIENT OR PUBLIC CONTRIBUTION

Data were collected from self-reported conditions and patients' clinical information.

REPORTING METHOD

STROBE checklist was employed.

[Association between obesity and Long-Covid: A narrative review]

To analyze the evidence in the scientific literature that relates Long-Covid and obesity, a narrative review of articles published in English and Spanish in Medline and Embase in the last 5years has been carried out. Infection with the SARS-CoV-2 virus causes a systemic inflammatory state increasing nutritional demand that favors sarcopenia in Long-Covid syndrome. It also causes endothelial dysfunction and a prothrombotic state that favors the formation of microthrombi and tissue hypoxia. A healthy and balanced diet is essential to treat obesity in addition to modifying the microbiota in Long-Covid and promoting physical and mental well-being. Obesity is an independent risk factor that increases the need for hospitalization, cardiovascular risk and mortality, as well as susceptibility to Long-Covid. Adipose tissue is a good reservoir of the virus, enhancing the comorbidities associated with obesity (high blood pressure, diabetes mellitus, dyslipidemia or fatty liver). There is insufficient evidence to recommend nutritional supplements to improve Long-Covid symptoms.

Stay Active, Stay Healthy: A Cross-Sectional View of the Impact of Physical Activity Levels on Health Parameters of Older Adults Institutionalized in Nursing Homes of Barcelona

(1) Background: Institutionalized older adults represent a vulnerable population. It is important to understand that higher levels of physical activity in older adults are associated with less risk of cardiovascular diseases, better cognition, and lower inflammaging and sarcopenia levels. The main objective was to evaluate the differences in health parameters in institutionalized older adults who perform different levels of weekly physical activity. The secondary objective was to analyze if weekly physical activity levels are a predictor of health parameters. (2) Methods: A cross-sectional observational study was conducted in nursing homes with adults over 75 years of age. A total of 76 participants was divided into three groups based on their weekly physical exercise frequency (1 day/week, 2 days/week, and 3 days/week). We measured demographic and anthropometric variables, along with cognitive level through the Mini Exam of Lobo. Handgrip strength, leg muscle strength, and power were also evaluated, and C-reactive protein levels were assessed through blood tests. Physical performance was measured using the Short Physical Performance Battery and walking speed. (3) Results: Significant differences were found in body mass index (p < 0.01; ES = 0.96), muscular strength (p < 0.01; ES = 0.70), and power (p < 0.01; ES = 1.09), Short Physical Performance Battery (p < 0.01; ES = 1.46) and walking speed (p < 0.01; ES = 0.87), cognitive function (p < 0.01; ES = 1.21), and C-reactive protein levels (p < 0.01; ES = 1.73), favoring the group who performed 3 days/week of physical activity. (4) Conclusions: Institutionalized older adults with three days per week of physical activity have greater physical and muscle function and less cognitive decline. Three days of weekly physical activity is associated with systemic inflammation and better cognitive status in institutionalized older adults.

Multi-omic profiling of sarcopenia identifies disrupted branched-chain amino acid catabolism as a causal mechanism and therapeutic target

Sarcopenia is a geriatric disorder characterized by a gradual loss of muscle mass and function. Despite its prevalence, the underlying mechanisms remain unclear, and there are currently no approved treatments. In this study, we conducted a comprehensive analysis of the molecular and metabolic signatures of skeletal muscle in patients with impaired muscle strength and sarcopenia using multi-omics approaches. Across discovery and replication cohorts, we found that disrupted branched-chain amino acid (BCAA) catabolism is a prominent pathway in sarcopenia, which leads to BCAA accumulation and decreased muscle health. Machine learning analysis further supported the causal role of BCAA catabolic dysfunction in sarcopenia. Using mouse models, we validated that defective BCAA catabolism impairs muscle mass and strength through dysregulated mTOR signaling, and enhancing BCAA catabolism by BT2 protects against sarcopenia in aged mice and in mice lacking Ppm1k, a positive regulator of BCAA catabolism in skeletal muscle. This study highlights improving BCAA catabolism as a potential treatment of sarcopenia.

Daily Supplementation with Protein-Enriched Lacto-Vegetarian Soups and Muscle Health in Community-Dwelling Older Adults: A Randomized Controlled Trial

BACKGROUND

Dietary protein adequacy is crucial for muscle health in aging individuals, posing a particular challenge for vegetarian seniors. This randomized controlled trial (RCT) investigates the impacts of protein-enriched lacto-vegetarian soup supplementation on body composition, physical performance and muscle strength functional assessment as well as cardiometabolic and inflammatory biomarkers in older adults.

METHODS

We enrolled 100 participants ≥65 years at risk for malnutrition (MNA-SF ≤ 11) and at risk for sarcopenia (SARC-F ≥4 or SARC-CalF ≥11) in this RCT. Participants were randomized assigned to receive a daily protein-enriched lacto-vegetarian soup (24-30 g protein) or usual diet. Primary outcomes of interest including (1) body composition (anthropometric measurements and body composition measured by bioimpedance analysis (BIA)), (2) physical performance (Short Physical Performance Battery, SPPB) and muscle strength (hand grip strength), and (3) functional assessments (including sarcopenia risk scales and nutritional status) as well as secondary outcomes of interests including cardiometabolic and inflammatory biomarkers were assessed at baseline and the 12th week of follow-up.

RESULTS

Data of 97 participants (intervention: n = 48, control: n = 49) were analyzed. Despite no significant changes in body composition were observed in the intervention group, compared to the usual diet, those who received protein-enriched lacto-vegetarian soup supplementation had an improved physical performance including an increase in SPPB score (β = 0.83 [95% CI 0.15-1.51], p = 0.02), a decrease in time to complete the 5 times chair rise test (β = -2.25 [-4.04 to -0.44], p = 0.01). Some functional assessments, including improved sarcopenia risk scale (e.g., SARC-F score [β = -0.68, p = 0.04]) and nutritional status (e.g., MNA-SF score [β = 0.44, p = 0.03]) were also observed.

CONCLUSIONS

Daily supplementation with protein-enriched lacto-vegetarian soups enhanced physical performance and functional assessments (such as sarcopenia risk scale and nutritional status) among older adults at risk of malnutrition and sarcopenia. Further study is needed to explore the long-term benefits of protein-enriched lacto-vegetarian soup supplementation for healthy aging.

A Scoping Review of the Implications and Applications of Body Composition Assessment in Locally Advanced and Locally Recurrent Rectal Cancer

Background: A strong body of evidence exists demonstrating deleterious relationships between abnormal body composition (BC) and outcomes in non-complex colorectal cancer. Complex rectal cancer (RC) includes locally advanced and locally recurrent tumours. This scoping review aims to summarise the current evidence examining BC in complex RC. Methods: A literature search was performed on Ovid MEDLINE, EMBASE, and Cochrane databases. Original studies examining BC in adult patients with complex RC were included. Two authors undertook screening and full-text reviews. Results: Thirty-five studies were included. Muscle quantity was the most commonly studied BC metric, with sarcopenia appearing to predict mortality, recurrence, neoadjuvant therapy outcomes, and postoperative complications. In particular, 10 studies examined relationships between BC and neoadjuvant therapy response, with six showing a significant association with sarcopenia. Only one study examined interventions for improving BC in patients with complex RC, and only one study specifically examined patients undergoing pelvic exenteration. Marked variation was also observed in terms of how BC was quantified, both in terms of anatomical location and how cut-off values were defined. Conclusions: Sarcopenia appears to predict mortality and recurrence in complex RC. An opportunity exists for a meta-analysis examining poorer BC and neoadjuvant therapy outcomes. There is a paucity of studies examining interventions for poor BC. Further research examining BC specifically in patients undergoing pelvic exenteration surgery is also lacking. Pitfalls identified include variances in how BC is measured on computed tomography and whether external cut-off values for muscle and adipose tissue are appropriate for a particular study population.

Machine learning based on nutritional assessment to predict adverse events in older inpatients with possible sarcopenia

BACKGROUND

The accuracy of current tools for predicting adverse events in older inpatients with possible sarcopenia is still insufficient to develop individualized nutrition-related management strategies. The objectives were to develop a machine learning model based on nutritional assessment for the prediction of all-cause death and infectious complications.

METHODS

A cohort of older patients with possible sarcopenia (divided into training group [70%] and validation group [30%]) from 30 hospitals in 14 major cities in China was retrospectively analyzed. Clinical characteristics, laboratory examination, Nutritional risk Screening-2002 (NRS-2002) and mini-nutritional Assessment-Short form (MNA-SF) were used to construct machine learning models to predict in-hospital adverse events, including all-cause mortality and infectious complications. The applied algorithms included decision tree, random forest, gradient boosting machine (GBM), LightGBM, extreme gradient boosting and neural network. Model performance was assessed according to learning a series of learning metrics including area under the receiver operating characteristic curve (AUC) and accuracy.

RESULTS

Among 3 999 participants (mean age 75.89 years [SD 7.14]; 1 805 [45.1%] were female), 373 (9.7%) had adverse events, including 62 (1.6%) of in-hospital death and 330 (8.5%) of infectious complications. The decision tree model showed a better AUC of 0.7072 (95% CI 0.6558-0.7586) in the validation cohort, using the five most important variables (i.e., mobility, reduced food intake, white blood cell count, upper arm circumference, and hypoalbuminemia).

CONCLUSIONS

Machine learning prediction models are feasible and effective for identifying adverse events, and may be helpful to guide clinical nutrition decision-making in older inpatients with possible sarcopenia.

Effects of 12-month physical and cognitive training on sarcopenia determinants in older adults: a subgroup analysis of a randomised clinical trial

BACKGROUND

Low physical activity is a major risk for sarcopenia. Whether training according to physical activity guidelines accompanied with cognitive training is effective on sarcopenia, remains unclear.

AIMS

We investigated whether the effects of 12-month physical and cognitive training (PTCT) and physical training (PT) on grip and knee extension strength, muscle mass, and walking speed differed between older adults with and without sarcopenia.

METHODS

Community-dwelling older adults (N = 314, mean age 74.5 ± 3.8 years, 60% women) who did not meet physical activity guidelines were randomized to PTCT and PT groups. PT for both groups included supervised and home-based multicomponent physical training. Cognitive training (CT) included computer-based exercises for executive functioning. Sarcopenia was determined according to the European Working Group on Sarcopenia in Older People 2019 criteria. Generalized estimation equation analysis were conducted.

RESULTS

Compared to PT, PTCT had no additive effect on strength, muscle mass, or walking speed in participants with or without sarcopenia. In pooled data (PT + PTCT) change in the grip strength was greater in sarcopenia (n = 49) group compared to non-sarcopenia (n = 264) group (interaction, p =.014). Both groups improved knee extension strength, and walking speed, but no statistically significant difference between the groups were observed. Muscle mass did not change in either group.

CONCLUSION

Physical training according to physical activity recommendations improves muscle strength, walking speed, and maintains muscle mass in sarcopenia. Additional cognitive training had no benefits on these outcomes.

TRIAL REGISTRATION NUMBER

ISRCTN52388040 and date of registration 20/1/2017.

Prospects for the diagnosis and treatment of sarcopenia in the Philippines

Over the past decade, the elderly Filipino population has significantly increased, rising from 4.6 million seniors, which was approximately 6% of the total population in 2000, to 6.5 million, or around 6.9% of the population in 2010. Projections suggest that by 2030, the percentage of the population aged 60 and above will increase to between 10 and 19%, indicating a significant demographic shift toward an aging population. This shift from a predominantly young population to a rapidly growing elderly demographic underscores the urgent need for effective health promotion and management programs targeting older adults. Sarcopenia, a muscle-wasting disorder, represents a significant global health challenge, particularly affecting the elderly. In the Philippines, the impact of sarcopenia is expected to become more pronounced, potentially straining both individuals and the national healthcare system over the next 15 years, despite the country's relatively younger overall population. Despite the expanding research on sarcopenia in the Philippines, there remains an urgent need to raise awareness and implement proactive measures to address this escalating health issue.

Primary Roles of Branched Chain Amino Acids (BCAAs) and Their Metabolism in Physiology and Metabolic Disorders

Leucine, isoleucine, and valine are collectively known as branched chain amino acids (BCAAs) and are often discussed in the same physiological and pathological situations. The two consecutive initial reactions of BCAA catabolism are catalyzed by the common enzymes referred to as branched chain aminotransferase (BCAT) and branched chain α-keto acid dehydrogenase (BCKDH). BCAT transfers the amino group of BCAAs to 2-ketoglutarate, which results in corresponding branched chain 2-keto acids (BCKAs) and glutamate. BCKDH performs an oxidative decarboxylation of BCKAs, which produces their coenzyme A-conjugates and NADH. BCAT2 in skeletal muscle dominantly catalyzes the transamination of BCAAs. Low BCAT activity in the liver reduces the metabolization of BCAAs, but the abundant presence of BCKDH promotes the metabolism of muscle-derived BCKAs, which leads to the production of glucose and ketone bodies. While mutations in the genes responsible for BCAA catabolism are involved in rare inherited disorders, an aberrant regulation of their enzymatic activities is associated with major metabolic disorders such as diabetes, cardiovascular disease, and cancer. Therefore, an understanding of the regulatory process of metabolic enzymes, as well as the functions of the BCAAs and their metabolites, make a significant contribution to our health.

Exercise and nutrition benefit skeletal muscle: From influence factor and intervention strategy to molecular mechanism

Sarcopenia is a progressive systemic skeletal muscle disease induced by various physiological and pathological factors, including aging, malnutrition, denervation, and cardiovascular diseases, manifesting as the decline of skeletal muscle mass and function. Both exercise and nutrition produce beneficial effects on skeletal muscle growth and are viewed as feasible strategies to prevent sarcopenia. Mechanisms involve regulating blood flow, oxidative stress, inflammation, apoptosis, protein synthesis and degradation, and satellite cell activation through exerkines and gut microbiomes. In this review, we summarized and discussed the latest progress and future development of the above mechanisms for providing a theoretical basis and ideas for the prevention and treatment of sarcopenia.

Addressing Inflammaging and Disease-Related Malnutrition: Adequacy of Oral Nutritional Supplements in Clinical Care

BACKGROUND

Disease-related malnutrition, with or without inflammation, in older adults is currently emerging as a public health priority. The use of Foods for Special Medical Purposes, including Oral Nutritional Supplements, and supplements is crucial to support patients in achieving their nutritional needs. Therefore, this article aims to comprehensively provide an analysis of the adequacy of FSMPs in meeting the nutritional requirements of different age-related diseases and takes into account the emerging role of inflammation. Moreover, it provides an identikit of the ideal products, following the pathology-specific guidelines.

METHODS

Data on 132 products were gathered through face-to-face meetings with companies' consultants. Specifically, information on energy, macronutrient, and micronutrient contents were collected, as well as on texture and flavors, osmolarity, cost, and packaging.

RESULTS

Most FSMPs met the daily recommendations for energy and protein intake. Nonetheless, few products contained β-hydroxy-β-methylbutyrate, optimal Branched-Chain Amino Acids ratios, arginine, glutamine, and omega-3 fatty acids. Furthermore, a marked predominance of FSMPs with a high osmolarity (85.7%), sweet taste (72%), and only animal protein content (79.5%) was observed. Cost analysis of FSMPs revealed a mean cost of EUR 5.35/portion. Products were mostly adequate for cancer, neurodegenerative diseases, diabetes, inflammatory bowel disease, end-stage kidney disease, dysphagiam and chronic obstructive pulmonary disease. However, gaps have been found for sarcopenia and abdominal surgery.

CONCLUSION

In light of the current market landscape, there is a need for a comprehensive regulation that indicates the optimal composition of FSMPs and the production of such products to tackle disease-related malnutrition.

Types, design, implementation, and evaluation of nutrition interventions in older people in Africa: A scoping review protocol

INTRODUCTION

Africa's older population is increasing and this, necessitates the development of interventions to promote healthy ageing. Nutrition is a key determinant of healthy ageing and local contextual evidence is needed to inform nutritional intervention development in Africa. There are already reviews on nutritional status and food insecurity in older adults in Africa. However, a synthesis of nutrition interventions targeting older people specifically, is lacking. Therefore, this protocol describes a scoping review that aims to systematically synthesise current evidence on nutrition interventions for older people in Africa.

METHODS

The review will involve: a review of available reviews on nutrition in older people in Africa (Phase 1); a review of nutrition interventions developed or implemented among older people in Africa (Phase 2); and consultation with local nutrition stakeholders in Zimbabwe, and The Gambia to contextualise Phase 1 and 2 findings and solicit insights not in the published literature (Phase 3). Searches for Phases 1 and 2 will include bibliographic databases (MEDLINE, EMBASE, Web of Science, African Journals Online, African Index Medicus) and grey literature sources (i.e. relevant websites). Title, abstract, and full-text screening will be conducted in duplicate, data extracted using piloted tools and findings summarised using descriptive statistics and narrative text. Phase 3 will be conducted using hybrid workshops, audio-recorded, detailed notes taken, and findings combined with those from Phases 1 and 2.

CONCLUSION

The findings of this review will summarise current evidence on nutrition in older people in Africa and inform nutrition intervention development. The findings will be presented in conferences, meetings, and published open access.

TRIAL REGISTRATION

This scoping review has been registered in OSF, registration DOI: https://doi.org/10.17605/OSF.IO/FH74T.

Double-Edge Effects of Leucine on Cancer Cells

Leucine is an essential amino acid that cannot be produced endogenously in the human body and therefore needs to be obtained from dietary sources. Leucine plays a pivotal role in stimulating muscle protein synthesis, along with isoleucine and valine, as the group of branched-chain amino acids, making them one of the most popular dietary supplements for athletes and gym-goers. The individual effects of leucine, however, have not been fully clarified, as most of the studies so far have focused on the grouped effects of branched-chain amino acids. In recent years, leucine and its metabolites have been shown to stimulate muscle protein synthesis mainly via the mammalian target of the rapamycin complex 1 signaling pathway, thereby improving muscle atrophy in cancer cachexia. Interestingly, cancer research suggests that leucine may have either anti-cancer or pro-tumorigenic effects. In the current manuscript, we aim to review leucine's roles in muscle protein synthesis, tumor suppression, and tumor progression, specifically summarizing the molecular mechanisms of leucine's action. The role of leucine is controversial in hepatocellular carcinoma, whereas its pro-tumorigenic effects have been demonstrated in breast and pancreatic cancers. In summary, leucine being used as nutritional supplement for athletes needs more attention, as its pro-oncogenic effects may have been identified by recent studies. Anti-cancer or pro-tumorigenic effects of leucine in various cancers should be further investigated to achieve clear conclusions.

Associations between serum cystatin C and fall reports in an Elderly population

Fall is common in the elderly, and chronic kidney disease is considered a major risk factor. Serum creatinine (Cre) and cystatin C (Cys C) are commonly used biomarkers for renal function, while the ratio of Cre to Cys C, known as the sarcopenia index (SI), provides insights into muscle health. This study investigates the relationships between Cre, Cys C, estimated glomerular filtration rates (eGFR), SI, and self-reported falls using National Health and Nutrition Examination Survey (NHANES) data. We included 4,272 older adults with eGFR > 30mL/min/1.73m2 from NHANES (1999 to 2004) and divided them into the fall and non-fall groups based on the questionnaires. Correlations were assessed using restricted cubic spline, weighted generalized linear regression models. Multi-factor logistic regression analysis identified serum Cys C as significantly associated with falls (all participants: OR 1.16, 95% CI: 1.09 to 1.23, p < 0.001; participants with eGFR > 75 mL/min/1.73m2: OR 1.17, 95% CI: 1.05 to 1.30, p < 0.001,). In contrast, Cre and eGFR were not significant after adjustments; SI showed marginal significance (p = 0.045). Cys C is significantly associated with fall risk in older adults, demonstrating a positive linear relationship with self-reported falls.

Demographic risk factors of pro-inflammatory diet: a narrative review

While inflammation is a known beneficial mechanism, pro-inflammatory nutrients can lead to chronic inflammation. The energy-adjusted dietary inflammatory index (E-DII) has revealed positive associations with chronic inflammatory diseases. However, more evidence about the demographic risk factors for high E-DII is needed. Therefore, the present study reviewed the high-risk groups of people for high E-DII scores. Men had higher E-DII than women worldwide, which could be explained by the craving for energy induced by stress and higher physical activity. However, in some societies, women had higher consumption of a pro-inflammatory diet, which could be induced by compulsive eating and craving for more sweets and carbohydrates during menstruation and also can be seen among women with premenopausal syndrome. The pro-inflammatory diets were more common among elders in southern America, East Asia, and Arab countries, while some other studies had contradictory results. The proliferation of unhealthy foods, such as fast food and Western dietary patterns enriched with a pro-inflammatory diet, increased youth's E-DII and decreased the healthy eating index among older people. Also, smokers and alcoholics tended to consume a diet with a higher E-DII, which should be investigated in further studies. Black people consumed the most pro-inflammatory diets compared with White people, especially in pregnant women. Education had a negative association with E-DII, while socioeconomic status was positively associated with a pro-inflammatory diet. Therefore, E-DII consumption had no association with access to healthy foods but is more associated with knowledge and cultural dietary habits. Moreover, further nutritional interventions are required to educate the vulnerable populations and also provide better availability of healthy food enriched with anti-inflammatory nutrients in the future.

Nutritional strategies for improving sarcopenia outcomes in older adults: A narrative review

Sarcopenia is characterized by a decline in muscle strength, generalized loss of skeletal muscle mass, and impaired physical performance, which are common outcomes used to screen, diagnose, and determine severity of sarcopenia in older adults. These outcomes are associated with poor quality of life, increased risk of falls, hospitalization, and mortality in this population. The development of sarcopenia is underpinned by aging, but other factors can lead to sarcopenia, such as chronic diseases, physical inactivity, inadequate dietary energy intake, and reduced protein intake (nutrition-related sarcopenia), leading to an imbalance between muscle protein synthesis and muscle protein breakdown. Protein digestion and absorption are also modified with age, as well as the reduced capacity of metabolizing protein, hindering older adults from achieving ideal protein consumption (i.e., 1-1.5 g/kg/day). Nutritional supplement strategies, like animal (i.e., whey protein) and plant-based protein, leucine, and creatine have been shown to play a significant role in improving outcomes related to sarcopenia. However, the impact of other supplements (e.g., branched-chain amino acids, isolated amino acids, and omega-3) on sarcopenia and related outcomes remain unclear. This narrative review will discuss the evidence of the impact of these nutritional strategies on sarcopenia outcomes in older adults.

Associations between physical fitness, body composition, and heart rate variability during exercise in older people: exploring mediating factors

Background

Age-related changes in body composition affect physical fitness in older adults. However, whether the autonomic response is associated with body fat percentage and its implication for physical fitness is not fully understood.

Aim

To understand the association between physical fitness, body composition, and heart rate variability in older people and its mediating factors.

Methods

A cross-sectional study with 81 older adults was conducted, assessing Short Physical Performance Battery (SPPB), Two-minute Step Test (TMST), body composition, and cardiac autonomic response. Correlation and mediation analyses were performed.

Results

Body fat percentage negatively correlated with physical fitness (SPPB: r =  - 0.273, p = 0.015; TMST: r =  - 0.279, p = 0.013) and sympathetic activity (sympathetic nervous system (SNS) index: r =  - 0.252, p = 0.030), yet positively correlated with parasympathetic tone (root mean square of successive differences (RMSSD): r = 0.253, p = 0.029; standard deviation of NN intervals (SDNN): r = 0.269, p = 0.020). Physical fitness associated with sympathetic nervous system index (SPPB: r = 0.313, p = 0.006; TMST: r = 0.265, p = 0.022) and parasympathetic nervous system index (TMST: r =  - 0.344, p = 0.003). Muscle mass mediated body fat's impact on physical fitness, while physical fitness mediated body fat's impact on autonomic response.

Conclusion

Body composition and cardiac autonomic response to exercise are associated with physical fitness in older people, highlighting a possible protective effect of muscle mass against the decline in physical fitness associated with increased body fat.

Effects of Otago exercise program on physical function in older adults: A systematic review and meta-analysis of randomized controlled trials

BACKGROUND

Maintaining physical function is critical for older adults to achieve healthy aging. The Otago exercise program (OEP) has been widely used to prevent falls for older adults. However, the effects of OEP on physical function remain controversial and the possible effects modifiers have not been assessed.

OBJECTIVE

To evaluate the effects of OEP on physical function in older adults and to explore potential moderators underlying the effects of OEP.

METHODS

We searched five electronic databases and relevant systematic reviews to identify studies. We included randomized controlled trials (RCTs) evaluating the effects of OEP as a single intervention on physical function among older adults aged 65 and over. Meta-analysis was performed using the random-effects model. Standardized mean differences (SMD) for physical function changes, pertinent to balance, strength, and mobility, were outcome measures. Subgroup analyses on exercise protocol and participants' characteristics were performed.

RESULTS

Thirteen RCTs consisting of 2402 participants were included in this systematic review and meta-analysis. Results indicated a significant effect of OEP on balance (SMD = 0.59, 95 % CI: 0.22∼0.96), lower body strength (SMD = 0.93, 95 % CI: 0.31∼1.55), and mobility (SMD = -0.59, 95 % CI: -0.95∼-0.22) against control groups. No significant OEP effects were found on upper body strength (MD = 1.48, 95 % CI: -0.58∼3.55). Subgroup analysis revealed that the video-supported delivery mode was more effective for improving balance (P = 0.04) and mobility (P = 0.02) than the face-to-face mode. Session durations over 30 min was more effective on lower body strength (P < 0.001) and mobility (P < 0.001) than those 1-30 min. Program period of 13-26 weeks was more effective on mobility (P = 0.02) than those of 4-12 weeks. However, the effects of OEP on physical function were not associated with age groups, and baseline falling risks.

CONCLUSION

The OEP could improve physical function including balance, lower body strength, and mobility in older adults. Implementing the OEP in video-supported, more than 30 min per session and 4-12 weeks may be the most appropriate and effective exercise protocol for improving physical function among older adults. More RCTs with rigorous design and larger scale are needed to further assess the effectiveness of diverse OEP protocols and quantify the dose-effect relationship.

Exploring causal effects of sarcopenia on risk and progression of Parkinson disease by Mendelian randomization

Previous observational studies suggested that sarcopenia is associated with Parkinson disease (PD), but it is unclear whether this association is causal. The objective of this study was to examine causal associations between sarcopenia-related traits and the risk or progression of PD using a Mendelian randomization (MR) approach. Two-sample bidirectional MR analyses were conducted to evaluate causal relationships. Genome-wide association study (GWAS) summary statistics for sarcopenia-related traits, including right handgrip strength (n = 461,089), left handgrip strength (n = 461,026), and appendicular lean mass (n = 450,243), were retrieved from the IEU OpenGWAS database. GWAS data for the risk of PD were derived from the FinnGen database (4235 cases; 373,042 controls). Summary-level data for progression of PD, including progression to Hoehn and Yahr stage 3, progression to dementia, and development of levodopa-induced dyskinesia, were obtained from a recent GWAS publication on progression of PD in 4093 patients from 12 longitudinal cohorts. Significant causal associations identified in MR analysis were verified through a polygenic score (PGS)-based approach and pathway enrichment analysis using genotype data from the Parkinson's Progression Markers Initiative. MR results supported a significant causal influence of right handgrip strength (odds ratio [OR] = 0.152, 95% confidence interval [CI] = 0.055-0.423, adjusted P = 0.0036) and appendicular lean mass (OR = 0.597, 95% CI = 0.440-0.810, adjusted P = 0.0111) on development of levodopa-induced dyskinesia. In Cox proportional hazard analysis, higher PGSs for right handgrip strength (hazard ratio [HR] = 0.225, 95% CI = 0.095-0.530, adjusted P = 0.0019) and left handgrip strength (HR = 0.303, 95% CI = 0.121-0.59, adjusted P = 0.0323) were significantly associated with a lower risk of developing levodopa-induced dyskinesia, after adjusting for covariates. Pathway enrichment analysis revealed that genome-wide significant single-nucleotide polymorphisms for right handgrip strength were substantially enriched in biological pathways involved in the control of synaptic plasticity. This study provides genetic evidence of the protective role of handgrip strength or appendicular lean mass on the development of levodopa-induced dyskinesia in PD. Sarcopenia-related traits can be promising prognostic markers for levodopa-induced dyskinesia and potential therapeutic targets for preventing levodopa-induced dyskinesia in patients with PD.

Dietary Protein and Physical Exercise for the Treatment of Sarcopenia

Sarcopenia is a multifactorial age-related disorder that causes a decrease in muscle mass, strength, and function, leading to alteration of movement, risk of falls, and hospitalization. This article aims to review recent findings on the factors underlying sarcopenia and the strategies required to delay and counteract its symptoms. We focus on molecular factors linked to ageing, on the role of low-grade chronic and acute inflammatory conditions such as cancer, which contributes to the onset of sarcopenia, and on the clinical criteria for its diagnosis. The use of drugs against sarcopenia is still subject to debate, and the suggested approaches to restore muscle health are based on adequate dietary protein intake and physical exercise. We also highlight the difference in the amount and quality of amino acids within animal- and plant-based diets, as studies have often shown varying results regarding their effect on sarcopenia in elderly people. In addition, many studies have reported that non-pharmacological approaches, such as an optimization of dietary protein intake and training programs based on resistance exercise, can be effective in preventing and delaying sarcopenia. These approaches not only improve the maintenance of skeletal muscle function, but also reduce health care costs and improve life expectancy and quality in elderly people.

Crosstalk between skeletal muscle ratio and cholesterol metabolism disorders: a cross-section study

BACKGROUND

Dysfunction of cholesterol metabolism may be associated with low skeletal muscle mass.  This study aimed to explore the relationship between skeletal muscle mass and cholesterol metabolic disorders in adults.

METHODS

The data of a total of 5949 people with complete medical history data, biochemical data and body composition analysis were recruited. According to the serum cholesterol, low density lipoprotein (LDL), high density lipoprotein (HDL) and nonHDL, the population was divided into a disorder group and a normal group. Independent sample t tests, chi-square tests, Pearson's correlation analyses and binary logistic regression analyses were used to study the effect of body composition on abnormal cholesterol metabolism. According to BMI and sex, the population was divided into different subgroups, and binary logistic regression analysis was used to study the effect of the skeletal mass ratio on cholesteral metabolic disorders in different subgroups.

RESULTS

There were significant differences in sex, alcohol consumption, body weight, BMI, skeletal muscle mass index (SMI) [total skeletal muscle mass (kg)/height 2 (m2)] and skeletal muscle mass ratio (SMR) [total skeletal muscle mass (kg)/weight (kg) *100] between the disorder group (hypercholesterolemia, hyper-LDL, lower-HDL and hyper-nonHDL) and the normal group. Pearson correlation analysis revealed that the SMR was negatively correlated, while the SMI was positively correlated with cholesterol metabolic disorders in both sexes. The overweight group was older and had a greater SMI, abnormal cholesteral metabolism ratio and lower SMR than the normal-weight group. In the normal-weight group, the SMR was an independent protective factor against different kinds of cholesteral metabolic disorders in both sexes, while the SMI was a risk factor. In the overweight subgroup, the protective effect on HDL and nonHDL metabolism remained in the male subgroup but disappeared in the female subgroup. However, the SMI was an independent risk factor for different kinds of cholesteral metabolic disorders in both sexes.

CONCLUSIONS

SMR was an independent protective factor against cholesterol metabolic disorders in both males and females, especially in the normal weight group. SMI was an independent risk factor, especially in the overweight group.

Sarcopenia and aortic valve disease

Valvular heart disease, including calcific or degenerative aortic stenosis (AS), is increasingly prevalent among the older adult population. Over the last few decades, treatment of severe AS has been revolutionised following the development of transcatheter aortic valve replacement (TAVR). Despite improvements in outcomes, older adults with competing comorbidities and geriatric syndromes have suboptimal quality of life outcomes, highlighting the cumulative vulnerability that persists despite valve replacement. Sarcopenia, characterised by loss of muscle strength, mass and function, affects 21%-70% of older adults with AS. Sarcopenia is an independent predictor of short-term and long-term outcomes after TAVR and should be incorporated as a prognostic marker in preprocedural planning. Early diagnosis and treatment of sarcopenia may reduce morbidity and mortality and improve quality of life following TAVR. The adverse effects of sarcopenia can be mitigated through resistance training and optimisation of nutritional status. This is most efficacious when administered before sarcopenia has progressed to advanced stages. Management should be individualised based on the patient's wishes/preferences, care goals and physical capability. Exercise during the preoperative waiting period may be safe and effective in most patients with severe AS. However, future studies are needed to establish the benefits of prehabilitation in improving quality of life outcomes after TAVR procedures.

Advances in nutritional metabolic therapy to impede the progression of critical illness

With the advancement of medical care and the continuous improvement of organ support technologies, some critically ill patients survive the acute phase of their illness but still experience persistent organ dysfunction, necessitating long-term reliance on intensive care and organ support, known as chronic critical illness. Chronic critical illness is characterized by prolonged hospital stays, high mortality rates, and significant resource consumption. Patients with chronic critical illness often suffer from malnutrition, compromised immune function, and poor baseline health, which, combined with factors like shock or trauma, can lead to intestinal mucosal damage. Therefore, effective nutritional intervention for patients with chronic critical illness remains a key research focus. Nutritional therapy has emerged as one of the essential components of the overall treatment strategy for chronic critical illness. This paper aims to provide a comprehensive review of the latest research progress in nutritional support therapy for patients with chronic critical illness.

Long-Term Rehabilitation Therapy Is Effective for Physical Function in a Patient With Amyloid Light Chain Amyloidosis Complicated by Nephrotic Syndrome: A Case Report and Literature Review

We report on the rehabilitation of a patient with amyloid light chain (AL) amyloidosis complicated by nephrotic syndrome. Various symptoms produced by AL amyloidosis, including nephrotic syndrome, complicate rehabilitation therapy. In this case report, long-term physical therapy was initiated prior to autologous peripheral blood stem cell transplantation owing to the risk of further decline in physical function due to decreased mobility and physical activity. Patients were instructed on how to perform home exercise therapy. Furthermore, compliance was monitored using a checklist and regular face-to-face feedback. There was no increase in skeletal muscle mass, but improvements in grip strength, lower extremity muscle strength, and phase angle were observed after 24 weeks of physical therapy. Despite the absence of partial remission (urinary protein level of 3.5 g/gCre or higher), nephrotic syndrome demonstrated a trend toward improvement. Since the effectiveness of physical therapy in such patients has not yet been fully established, this report suggests that long-term rehabilitation therapy for physical function in patients with nephrotic syndrome complicated by persistent proteinuria may be effective.

Nutrition interventions for body composition, physical function, cognition in hospitalized older adults: A systematic review of individuals 75 years and older

BACKGROUND

Globally, the oldest old population is expected to triple by 2050. Hospitalization and malnutrition can result in progressive functional decline in older adults. Minimizing the impact of hospitalization on functional status in older adults has the potential to maintain independence, reduce health and social care costs, and maximize years in a healthy state. This study aimed to systematically review the literature to identify nutritional interventions that target physical function, body composition, and cognition in the older population (≥ 75 years).

METHODS

A systematic review was conducted to evaluate the efficacy of nutritional interventions on physical function, body composition, and cognition in adults aged ≥ 75 years or mean age ≥80 years. Searches of PubMed (National Institutes of Health, National Library of Medicine), Scopus (Elsevier), EMBASE (Elsevier), Cumulative Index to Nursing and Allied Health Literature (CINAHL) with Full Text (EBSCOhost), and PsycInfo (EBSCOhost) were conducted. Screening, data extraction, and quality assessment were performed in duplicate and independently (CRD42022355984; https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=355984).

RESULTS

Of 8311 citations identified, 2939 duplicates were excluded. From 5372 citations, 189 articles underwent full-text review leaving a total of 12 studies for inclusion. Interventions were food-based, protein-based, carbohydrate-based, personalized, or used parenteral nutrition. Ten studies monitored anthropometric or body composition changes with three showing maintenance or improvements in lean mass, body mass index, triceps skinfold, and mid-upper arm circumference compared with the control group. Six studies monitored physical function but only the largest study found a beneficial effect on activities of daily living. Two of three studies showed the beneficial effects of nutritional intervention on cognition.

CONCLUSION

There are few, high-quality, nutrition-based interventions in older adults ≥75 years. Despite heterogeneity, our findings suggest that large, longer-term (>2 weeks) nutritional interventions have the potential to maintain body composition, physical function, and cognition in adults aged 75 years and older during hospitalization.

Association between depressive symptoms and sarcopenia among middle-aged and elderly individuals in China: the mediation effect of activities of daily living (ADL) disability

BACKGROUND

Depressive symptoms and sarcopenia, often observed among middle-aged and elderly individuals, are significant health concerns in China, particularly given the country's rapidly aging population. Depressive symptoms, characterized by persistent feelings of sadness and loss of interest, can significantly impact quality of life. Little is known about the underlying pathway connecting these two conditions.

METHODS

The data for this study were derived from the China Health and Retirement Longitudinal Study (CHARLS). Depressive symptoms were evaluated using the Centre for Epidemiological Studies Depression (CSED) scale. Logistic regression analyses were employed to investigate the association between depressive symptoms, activities of daily living (ADL) disability, and sarcopenia, while adjusting for potential confounding factors. The selection of predictor variables, including social activity, chronic diseases, demographic factors, and lifestyle habits, was based on their known associations with mental health, physical functioning and sarcopenia. These variables were included to ensure a comprehensive adjustment for potential confounding factors and to provide a more accurate estimation of the relationship between depressive symptoms and sarcopenia. Additionally, mediation analysis was conducted to assess the mediating role of ADL disability in the relationship between depressive symptoms and sarcopenia.

RESULTS

A comprehensive study was conducted on a total of 8,238 participants aged 45 years and older, comprising 3,358 men and 4,880 women. Logistic regression analyses were conducted to identify significant associations between depressive symptoms (OR = 1.30, P = 0.0269,95%CI = 1.03-1.63), ADL disability (OR = 1.94, P < 0.001,95%CI = 1.37-2.75) and sarcopenia. The results revealed significant relationships among these variables. Furthermore, mediation effect analyses demonstrated that ADL disability partially mediated the association between depressive symptoms and sarcopenia (estimated indirect effect: 0.006, 95% CI: 0.003, 0.008, proportion of mediation effect: 20.00%).

CONCLUSIONS

The study underscores a significant association between depressive symptoms and sarcopenia among middle-aged and elderly individuals in China, with ADL disability acting as a mediator. These findings offer novel insights for targeted health interventions. Future interventions should effectively combat sarcopenia by integrating psychological support with muscle-strengthening exercise programs. By addressing both depressive symptoms and ADL disability, clinicians and public health professionals can enhance outcomes for this demographic. Collaborative efforts across disciplines are essential for providing comprehensive health management tailored to the needs of middle-aged and elderly individuals. Future research should longitudinally assess the impact of such integrated interventions on sarcopenia prevention and depressive symptom alleviation. Additionally, investigating the role of social and environmental factors in mediating this relationship is crucial for developing more effective health strategies for this vulnerable population.

Frontiers in sarcopenia: Advancements in diagnostics, molecular mechanisms, and therapeutic strategies

The onset of sarcopenia is intimately linked with aging, posing significant implications not only for individual patient quality of life but also for the broader societal healthcare framework. Early and accurate identification of sarcopenia and a comprehensive understanding of its mechanistic underpinnings and therapeutic targets paramount to addressing this condition effectively. This review endeavors to present a cohesive overview of recent advancements in sarcopenia research and diagnosis. We initially delve into the contemporary diagnostic criteria, specifically referencing the European Working Group on Sarcopenia in Older People (EWGSOP) 2 and Asian Working Group on Sarcopenia (AWGS) 2019 benchmarks. Additionally, we elucidate comprehensive assessment techniques for muscle strength, quantity, and physical performance, highlighting tools such as grip strength, chair stand test, dual-energy X-ray Absorptiometry (DEXA), bioelectrical impedance analysis (BIA), gait speed, and short physical performance battery (SPPB), while also discussing their inherent advantages and limitations. Such diagnostic advancements pave the way for early identification and unequivocal diagnosis of sarcopenia. Proceeding further, we provide a deep-dive into sarcopenia's pathogenesis, offering a thorough examination of associated signaling pathways like the Myostatin, AMP-activated protein kinase (AMPK), insulin/IGF-1 Signaling (IIS), and the nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) pathways. Each pathway's role in sarcopenia mediation is detailed, underscoring potential therapeutic target avenues. From a mechanistic perspective, the review also underscores the pivotal role of mitochondrial dysfunction in sarcopenia, emphasizing elements such as mitochondrial oxidative overload, mitochondrial biogenesis, and mitophagy, and highlighting their therapeutic significance. At last, we capture recent strides made in sarcopenia treatment, ranging from nutritional and exercise interventions to potential pharmacological and supplementation strategies. In sum, this review meticulously synthesizes the latest scientific developments in sarcopenia, aiming to enhance diagnostic precision in clinical practice and provide comprehensive insights into refined mechanistic targets and innovative therapeutic interventions, ultimately contributing to optimized patient care and advancements in the field.

The nutritional support to prevent sarcopenia in the elderly

Sarcopenia has been described as a muscle disease, with multiple adverse consequences on human health. Recommendations aimed at supporting awareness, prevention, early detection and treatment of this disease are needed. This review focuses on the epidemiology, pathophysiology and early detection of elderly sarcopenia. As far as treatment is concerned, physical activity and nutritional support are specifically evaluated. An individually tailored resistance exercise training program appears to be crucial for a positive outcome of the sarcopenia prevention and treatment. The nutritional intervention is mostly based on the supplementation with high-quality proteins (i.e., whey protein) in order to increase the intake of essential amino acids and in particular of leucine. In addition, of relevant importance appears to be the supplementation with vitamin D, with omega-3 fatty acids and probiotics. This review evaluates the results of the most qualified studies on the nutritional supplementation of sarcopenic elderly subjects and shows that promising results have been achieved in community elderly subjects, or subjects followed in rehabilitation centers and in nursing homes, with additional resistance exercise programs.

E-PROOF: E-intervention for protein intake and resistance training to optimize function: A study protocol

BACKGROUND

Accounting for more than 60% of cancer survivors, older (≥65 years) cancer survivors have a 2- to 5-fold risk of physical function impairment, compared to cancer-free peers. One strategy to improve physical function is dietary and resistance training interventions, which improve muscle strength and mass by stimulating muscle protein synthesis. The E-PROOF (E-intervention for Protein Intake and Resistance Training to Optimize Function) study will examine the feasibility, acceptability, and preliminary efficacy of a 12-week randomized controlled trial of an online, tailored nutritional and resistance training education and counseling intervention to improve physical function and associated health outcomes (muscle strength, health-related quality of life (HRQoL), self-efficacy, and weight management).

METHODS

In this study, 70 older cancer survivors will be randomized to one of two groups: experimental (receiving remote behavioral counseling and evidence-based education and resources), and control (general survivorship education). We will examine the intervention effects on physical function, muscle strength, HRQoL, self-efficacy, weight, and waist circumference during a 12-week period between the experimental and control groups. Three months following the end of the intervention, we will conduct a follow-up assessment to measure physical function, muscle strength, and HRQoL.

SIGNIFICANCE AND IMPACT

This study is the first synchronous, online protein-focused diet and resistance training intervention among older cancer survivors. This novel study advances science by promoting independent health behaviors among older cancer survivors to improve health outcomes, and provide foundational knowledge to further address this growing problem on a wider scale through online platforms.

Effect of Sustainably Sourced Protein Consumption on Nutrient Intake and Gut Health in Older Adults: A Systematic Review

Diet is integral to the healthy ageing process and certain diets can mitigate prolonged and deleterious inflammation. This review aims to assess the impact of diets high in sustainably sourced proteins on nutrient intake, gut, and age-related health in older adults. A systematic search of the literature was conducted on 5 September 2023 across multiple databases and sources. Studies assessing sustainably sourced protein consumption in community dwelling older adults (≥65 years) were included. Risk of bias (RoB) was assessed using 'RoB 2.0' and 'ROBINS-E'. Narrative synthesis was performed due to heterogeneity of studies. Twelve studies involving 12,166 older adults were included. Nine studies (n = 10,391) assessed habitual dietary intake and had some RoB concerns, whilst three studies (n = 1812), two with low and one with high RoB, conducted plant-based dietary interventions. Increased adherence to sustainably sourced diets was associated with improved gut microbial factors (n = 4640), healthier food group intake (n = 2142), and increased fibre and vegetable protein intake (n = 1078). Sustainably sourced diets positively impacted on gut microbiota and healthier intake of food groups, although effects on inflammatory outcomes and health status were inconclusive. Future research should focus on dietary interventions combining sustainable proteins and fibre to evaluate gut barrier function and consider inflammatory and body composition outcomes in older adults.

Novel dietary strategies to manage sarcopenia

PURPOSE OF REVIEW

Sarcopenia is a wasting disease, mostly age-related in which muscle strength and mass decline, such as physical performance. With aging, both lower dietary protein intake and anabolic resistance lead to sarcopenia. Moreover, aging and sarcopenia display low-grade inflammation, which also worsen muscle condition. In this review, we focused on these two main targets to study dietary strategies.

RECENT FINDINGS

The better understanding in mechanisms involved in sarcopenia helps building combined dietary approaches including physical activity that would slow the disease progression. New approaches include better understanding in the choice of quality proteins, their amount and schedule and the association with antioxidative nutrients.

SUMMARY

First, anabolic resistance can be countered by increasing significantly protein intake. If increasing amount remains insufficient, the evenly delivery protein schedule provides interesting results on muscle strength. Quality of protein is also to consider for decreasing risk for sarcopenia, because varying sources of proteins appears relevant with increasing plant-based proteins ratio. Although new techniques have been developed, as plant-based proteins display a lower availability, we need to ensure an adapted overall amount of proteins. Finally, specific enrichment with leucine from whey protein remains the dietary combined approach most studied and studies on citrulline provide interesting results. As cofactor at the edge between anabolic and antioxidative properties, vitamin D supplementation is to recommend. Antioxidative dietary strategies include both fibers, vitamins, micronutrients and polyphenols from various sources for positive effects on physical performance. The ω 3 -polyunsaturated fatty acids also display positive modifications on body composition. Gut microbiota modifiers, such as prebiotics, are promising pathways to improve muscle mass and function and body composition in sarcopenic patients. Nutritional interventions could be enhanced by combination with physical activity on sarcopenia. In healthy older adults, promoting change in lifestyle to get near a Mediterranean diet could be one of the best options. In sarcopenia adults in which lifestyle changes appears unprobable, specific enrichement potentialized with physical activity will help in the struggle against sarcopenia. Longitudinal data are lacking, which makes it hard to draw strong conclusions. However, the effects of a physical activity combined with a set of nutrition interventions on sarcopenia seems promising.

Digital Intervention (Keep-On-Keep-Up Nutrition) to Improve Nutrition in Older Adults: Protocol for a Feasibility Randomized Controlled Trial

BACKGROUND

Digital health tools can support behavior change and allow interventions to be scalable at a minimal cost. Keep-on-Keep-up Nutrition (KOKU-Nut) is a free, tablet-based app that focuses on increasing physical activity and improving the dietary intake of older adults based on UK guidelines. The intervention targets an important research area identified as a research priority reported by the James Lind Alliance priority setting partnership for malnutrition.

OBJECTIVE

This study aims to assess the feasibility of using the digital health tool KOKU-Nut among community-dwelling older adults to inform a future randomized controlled trial. The secondary aims are to determine the acceptability, usability, preliminary effect sizes, and safety of the study and the intervention (KOKU-Nut).

METHODS

This is a feasibility randomized controlled trial. We plan to recruit a total of 36 community-dwelling older adults using purposive sampling. Participants will be randomized 1:1 to either the intervention or the control group. The intervention group will be asked to engage with KOKU-Nut 3 times a week for 12 weeks. Participants in the control group will receive a leaflet promoting a healthy lifestyle. All study participants will complete questionnaires at baseline and the end of the 12 weeks. A sample of participants will be asked to participate in an optional interview. The study will collect a range of data including anthropometry (height and weight), dietary intake (3-day food diary), physical function (grip strength and 5-times sit-to-stand), perceived quality of life (EQ-5D), usability (System Usability Scale), and safety (adverse events).

RESULTS

Data collection commenced in March 2024, and the results will be ready for publication by January 2025. Feasibility will be determined on the basis of participants' self-reported engagement with the intervention, and recruitment and retention rates and will be summarized descriptively. We will also consider the amount of missing data and assess how outcomes are related to group assignment. Acceptability will be measured using the modified treatment evaluation inventory and one-to-one semistructured interviews. Transcripts from the interviews will be analyzed using NVivo (version 12; QSR International) software using framework analysis to understand any barriers to the recruitment process, the suitability of the assessment measures, and the acceptability of the intervention and study design.

CONCLUSIONS

The study aligns with guidelines developed by the Medical Research Council for developing a complex intervention by using qualitative and quantitative research to examine the barriers of the intervention and identify potential challenges around recruitment and retention. We anticipate that these results will inform the development of a future powered randomized controlled design trial to test the true effectiveness of KOKU-Nut.

TRIAL REGISTRATION

ClinicalTrials.gov NCT05943366; https://classic.clinicaltrials.gov/ct2/show/NCT05943366.

INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID)

PRR1-10.2196/50922.

Effect of whole-body vibration stimulation on plasma soluble TNF receptors in elderly with sarcopenia: a randomized controlled trial

Sarcopenia is a pathology resulting from a progressive and severe loss of muscle mass, strength, and function in the course of aging, which has deleterious consequences on quality of life. Among the most widespread studies on the issue are those focused on the effect of different types of physical exercise on patients with sarcopenia. This randomized controlled study aimed to compare the effects of a whole-body vibration exercise (WBV) session on the inflammatory parameters of non-sarcopenic (NSG, n=22) and sarcopenic elderly (SG, n=22). NSG and SG participants were randomly divided into two protocols: intervention (squat with WBV) and control (squat without WBV). After a one-week washout period, participants switched protocols, so that everyone performed both protocols. Body composition was assessed by dual-energy radiological absorptiometry (DXA) and function through the six-minute walk test (6MWD) and Short Physical Performance Battery (SPPB). Plasma soluble tumor necrosis factor receptors (sTNFR) were determined by enzyme-linked immunosorbent assay (ELISA) and measured before and immediately after each protocol. After exercise with WBV, there was an increase in sTNFR2 levels in the NSG (P<0.01; d=-0.69 (-1.30; -0.08) and SG (P<0.01, d=-0.95 (-1.57; -0.32) groups. In conclusion, an acute session of WBV influenced sTNFr2 levels, with sarcopenic individuals showing a greater effect. This suggested that WBV had a more pronounced impact on sTNFr2 in those with loss of muscle strength and/or physical performance. Additionally, WBV is gaining recognition as an efficient strategy for those with persistent health issues.

A Conceptual Study on Characterizing the Complexity of Nutritional Interventions for Malnourished Older Adults in Hospital Settings: An Umbrella Review Approach

INTRODUCTION

Malnutrition is a widespread and intricate issue among hospitalized adults, necessitating a wide variety of nutritional strategies to address its root causes and repercussions. The primary objective of this study is to systematically categorize nutritional interventions into simple or complex, based on their resource allocation, strategies employed, and predictors of intervention complexity in the context of adult malnutrition in hospital settings.

METHODS

A conceptual evaluation of 100 nutritional intervention studies for adult malnutrition was conducted based on data from a recent umbrella review (patient population of mean age > 60 years). The complexity of interventions was categorized using the Medical Research Council 2021 Framework for Complex Interventions. A logistic regression analysis was employed to recognize variables predicting the complexity of interventions.

RESULTS

Interventions were divided into three principal categories: education and training (ET), exogenous nutrient provision (EN), and environment and services (ES). Most interventions (66%) addressed two or more of these areas. A majority of interventions were delivered in a hospital (n = 75) or a hospital-to-community setting (n = 25), with 64 studies being classified as complex interventions. The logistic regression analysis revealed three variables associated with intervention complexity: the number of strategies utilized, the targeted areas, and the involvement of healthcare professionals. Complex interventions were more likely to be tailored to individual needs and engage multiple healthcare providers.

CONCLUSIONS

The study underlines the importance of considering intervention complexity in addressing adult malnutrition. Findings advocate for a comprehensive approach to characterizing and evaluating nutritional interventions in future research. Subsequent investigations should explore optimal balances between intervention complexity and resource allocation, and assess the effectiveness of complex interventions across various settings, while considering novel approaches like telehealth.

Ophiocephalus striatus Extract Supplementation Decreases Serum IL-6 Levels in Older People with Sarcopenia-A Single-Center Experience

Sarcopenia, a condition characterized by muscle loss and decreased function in older adults, is a growing public health concern. This study aimed to investigate the effects of Ophiocephalus striatus extract on insulin-like growth factor-1 serum, interleukin-6 serum levels, and sarcopenia-related parameters in older adults with sarcopenia. This double-blind randomized controlled trial included 80 older adults with sarcopenia. Participants were randomly assigned to receive Ophiocephalus striatus extract or a placebo for two weeks. The IGF-1 serum and IL-6 serum levels were assessed as primary outcomes. The Ophiocephalus striatus extract intervention resulted in a significant reduction in serum IL-6 levels. Although the IGF-1 levels did not show significant changes, there was an increase for the intervention group. This study demonstrated that a 2-week intervention with Ophiocephalus striatus extract positively impacted the serum IL-6 levels in older adults with sarcopenia. While the IGF-1 levels did not change significantly in this short intervention period, the observed improvements in IGF-1, calf circumference, muscle mass, and muscle strength are promising. The findings suggest that Ophiocephalus striatus extract may offer a valuable intervention for managing sarcopenia, particularly in regions with abundant Ophiocephalus striatus production, such as South Sumatera. This study was registered with trial number NCT05869383.

Mitochondrial involvement in sarcopenia

Sarcopenia lowers the quality-of-life for millions of people across the world, as accelerated loss of skeletal muscle mass and function contributes to both age- and disease-related frailty. Physical activity remains the only proven therapy for sarcopenia to date, but alternatives are much sought after to manage this progressive muscle disorder in individuals who are unable to exercise. Mitochondria have been widely implicated in the etiology of sarcopenia and are increasingly suggested as attractive therapeutic targets to help restore the perturbed balance between protein synthesis and breakdown that underpins skeletal muscle atrophy. Reviewing current literature, we note that mitochondrial bioenergetic changes in sarcopenia are generally interpreted as intrinsic dysfunction that renders muscle cells incapable of making sufficient ATP to fuel protein synthesis. Based on the reported mitochondrial effects of therapeutic interventions, however, we argue that the observed bioenergetic changes may instead reflect an adaptation to pathologically decreased energy expenditure in sarcopenic muscle. Discrimination between these mechanistic possibilities will be crucial for improving the management of sarcopenia.

Muscle strength and non-alcoholic fatty liver disease/metabolic-associated fatty liver disease

This editorial comments on an article published in a recent issue of World Journal of Gastroenterology, entitled "Association of low muscle strength with metabolic dysfunction-associated fatty liver disease: A nationwide study". We focused on the association between muscle strength and the incidence of non-alcoholic fatty liver disease (NAFLD) and metabolic-associated fatty liver disease (MAFLD), as well as the mechanisms underlying the correlation and related clinical applications. NAFLD, which is now redefined as MAFLD, is one of the most common chronic liver diseases globally with an increasing prevalence and is characterized by malnutrition, which may contribute to decreased muscle strength. Reduction of muscle strength reportedly has a pathogenesis similar to that of NAFLD/ MAFLD, including insulin resistance, inflammation, sedentary behavior, as well as insufficient vitamin D. Multiple studies have focused on the relationship between sarcopenia or muscle strength and NAFLD. However, studies investigating the relationship between muscle strength and MAFLD are limited. Owing to the shortage of specific medications for NAFLD/MAFLD treatment, early detection is essential. Furthermore, the relationship between muscle strength and NAFLD/MAFLD suggests that improvements in muscle strength may have an impact on disease prevention and may provide novel insights into treatments including dietary therapy, as well as tailored physical activity.

Obstacles to the Early Diagnosis and Management of Sarcopenia: Current Perspectives

Research in sarcopenia has grown exponentially over the last 15 years in geriatrics and gerontology, as well as other specialties, including oncology and hepatology. There is now strong evidence for the role of resistance exercise to prevent declines in muscle strength and function, especially when combined with nutritional optimization with protein supplementation. However, there remains a disparity between research evidence and clinical practice. There are multiple factors for this, which relate to the current diagnostic criteria for sarcopenia, practical and logistical aspects of diagnosis of sarcopenia, clinician knowledge of both diagnosis and management, and the availability of pathways for interventions. Sarcopenia is currently defined based on the identification of muscle strength, in combination with muscle size or quality, below cut-off thresholds at a single timepoint. This defines sarcopenia as a binary process of either present or not present, thus early diagnosis can be challenging. In this article, we summarize current obstacles to early diagnosis and management of sarcopenia in clinical practice, and make recommendations to how these might be overcome. This includes our recommendation of incorporation of handgrip strength measurement into standard care, to enable dynamic assessment and identification of early declines in handgrip strength, so that interventions can be implemented to prevent disability.

Association between endogenous plasma beta-hydroxy-beta-methylbutyrate levels and frailty in community-dwelling older people

BACKGROUND

Frailty is a key element in healthy ageing in which muscle performance plays a main role. Beta-hydroxy-beta-methylbutyrate (HMB) supplementation has shown favourable effects in modulating protein synthesis, improving muscle mass and function in interventional studies. Decreased age-related endogenous HMB levels have been shown in previous studies. The aim of the present study is to assess whether there is an association between endogenous plasma HMB levels and frailty.

METHODS

Data from 1290 subjects (56.98% women; mean ± standard deviation age 74.6 ± 5.95 years) from the Toledo Study for Healthy Aging were obtained. Participants had their frailty status qualified according to Fried's Frailty Phenotype (FFP) score and the Frailty Trait Scale in its 12-domain version (FTS-12). Plasma HMB levels were analysed by an ultrahigh-performance liquid chromatography tandem mass spectrometry. Differences between groups (frail vs. non-frail) were tested using Mann-Whitney U test, Kruskal-Wallis test and chi-squared test. The association between HMB and frailty was assessed by multivariate linear and logistic regressions when frailty was analysed as continuous and binary, respectively. Models were adjusted by age, gender, comorbidity, body composition and protein intake.

RESULTS

HMB levels were lower in those aged ≥75 years than in those aged 65-74 years, with an inverse linear relationship between age and HMB levels (β = -0.031; P = 0.018), mainly accounted by males (β = -0.062; P = 0.002). HMB levels were higher in men (0.238 ± 0.065 vs. 0.193 ± 0.051 ng/mL; P ≤ 0.001). HMB levels were significantly lower in frail than in non-frail individuals: 0.204 ± 0.058 versus 0.217 ± 0.063 ng/dL (P = 0.001) according to the FFP and 0.203 ± 0.059 versus 0.219 ± 0.063 ng/mL (P < 0.001) according to FTS-12. These differences showed a dose-dependent profile when we compared them by quintiles of HMB (P for trend: 0.022; 0.012 and 0.0004, respectively, for FFP, FTS-12 binary and FTS-12 continuous). Variables associated with low HMB levels were body mass index, strength, exhaustion and weight loss. Frailty was associated with HMB levels in all the adjusted models, including the fully adjusted ones, no matter the tool used (odds ratio: 0.45 [0.26, 0.77] for FFP and 0.36 [0.20, 0.63] for FTS-12 binary; β = -4.76 [-7.29, -2.23] for FTS-12 score). This association was also observed when the analyses were done by quintiles, showing such association since Q4 (FFP), Q2 (FTS-12 binary) and Q3 (FTS-12 score). The associations were observed in the whole sample and in each gender.

CONCLUSIONS

There is an inverse association between HMB levels and frailty status. These findings support the design of targeted clinical trials to evaluate the effect of HMB supplementation in older frail people with low HMB levels.

The influence of resistance exercise training prescription variables on skeletal muscle mass, strength, and physical function in healthy adults: An umbrella review

PURPOSE

The aim of this umbrella review was to determine the impact of resistance training (RT) and individual RT prescription variables on muscle mass, strength, and physical function in healthy adults.

METHODS

Following Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, we systematically searched and screened eligible systematic reviews reporting the effects of differing RT prescription variables on muscle mass (or its proxies), strength, and/or physical function in healthy adults aged >18 years.

RESULTS

We identified 44 systematic reviews that met our inclusion criteria. The methodological quality of these reviews was assessed using A Measurement Tool to Assess Systematic Reviews; standardized effectiveness statements were generated. We found that RT was consistently a potent stimulus for increasing skeletal muscle mass (4/4 reviews provide some or sufficient evidence), strength (4/6 reviews provided some or sufficient evidence), and physical function (1/1 review provided some evidence). RT load (6/8 reviews provided some or sufficient evidence), weekly frequency (2/4 reviews provided some or sufficient evidence), volume (3/7 reviews provided some or sufficient evidence), and exercise order (1/1 review provided some evidence) impacted RT-induced increases in muscular strength. We discovered that 2/3 reviews provided some or sufficient evidence that RT volume and contraction velocity influenced skeletal muscle mass, while 4/7 reviews provided insufficient evidence in favor of RT load impacting skeletal muscle mass. There was insufficient evidence to conclude that time of day, periodization, inter-set rest, set configuration, set end point, contraction velocity/time under tension, or exercise order (only pertaining to hypertrophy) influenced skeletal muscle adaptations. A paucity of data limited insights into the impact of RT prescription variables on physical function.

CONCLUSION

Overall, RT increased muscle mass, strength, and physical function compared to no exercise. RT intensity (load) and weekly frequency impacted RT-induced increases in muscular strength but not muscle hypertrophy. RT volume (number of sets) influenced muscular strength and hypertrophy.

Genetically Proxied Sarcopenia-Related Muscle Traits and Depression: Evidence from the FinnGen Cohort

BACKGROUND

Sarcopenia and depression are common and often coexist in the elderly. This study aims to determine the impact of sarcopenia-related muscle traits on depression.

METHODS

A two-sample Mendelian randomization (MR) study was performed on the summary-level data from the FinnGen cohort to estimate the causal association of appendicular lean mass (ALM), walking pace, or low hand grip strength with depression. Additionally, multivariable MR (MVMR) was performed to assess the dependence of each muscle trait in the causality and adjust the effect of body mass index (BMI). Supplementary backward MR analyses were performed to estimate the effect of depression on sarcopenia-related muscle traits.

RESULTS

Univariable MR analyses demonstrated that there were causal associations of ALM (odds ratio [OR]: 0.94; 95% confidence interval [CI]: 0.88-0.99), walking pace (OR: 0.53; 95% CI: 0.32-0.88), and low hand grip strength (OR: 1.20; 95% CI: 1.05-1.38) with depression. MVMR analyses showed that ALM was the only trait that had a significant causal relationship with depression (OR: 0.91; 95% CI: 0.85-0.98) after accounting for the other two muscle traits. Moreover, the independent association of ALM with depression remained (OR: 0.92; 95% CI: 0.85-0.99) after being adjusted by BMI. The backward MR analyses showed no causal associations of depression with any sarcopenia-related muscle traits.

CONCLUSION

Low muscle mass independently increases the risk of depression. This study determined the muscle-related risk factors of depression, which may help establish the causality between sarcopenia and depression and provide evidence-based recommendations for improving mental health in the elderly.