Molecular Mechanism and Pathogenesis of Sarcopenia: An Overview

Higher CALLY index levels indicate lower sarcopenia risk among middle-aged and elderly community residents as well as hospitalized patients

The C-reactive protein-albumin-lymphocyte (CALLY) index, which integrates albumin, lymphocytes, and C-reactive protein levels, has emerged as a novel method to assess nutritional and inflammatory statuses in patients. This study examined the correlation between the CALLY index and sarcopenia risk using two cohorts: 1804 community dwellers from the NHANES database in the United States and 139 patients from the Department of Gerontology at Kunshan Hospital, China. In the US community cohort, RCS curve analysis was used to examine the non-linear relationship between inflammatory/nutritional markers and sarcopenia, subgroup analysis was also conducted. Logistic regression was employed to evaluate the association between the CALLY index and the risk of sarcopenia in both cohorts. Results demonstrated a significant non-linear relationship between the CALLY index and the risk of sarcopenia (P < 0.001). Elevated levels of the CALLY index are independently linked to a decreased risk of sarcopenia in both community residents (OR = 0.35, 95% CI 0.20-0.57, Q3 CALLY index and OR = 0.26, 95% CI 0.11-0.56, Q4 CALLY index) and hospitalized patients (OR = 0.35, 95% CI 0.12-0.96). This finding identified low CALLY index as a conveniently measurable parameter, serving as a nutritional and inflammatory risk factor for sarcopenia.

Effects and Mechanisms of Polyunsaturated Fatty Acids on Age-Related Musculoskeletal Diseases: Sarcopenia, Osteoporosis, and Osteoarthritis-A Narrative Review

Background: The process of the globally aging population has been accelerating, leading to an increasing social burden. As people age, the musculoskeletal system will gradually go through a series of degenerative and loss of function and eventually develop age-related musculoskeletal diseases, like sarcopenia, osteoporosis, and osteoarthritis. On the other hand, several studies have shown that polyunsaturated fatty acids (PUFAs) possess various important physiological functions on the health of muscles, bones, and joints. Objective: This narrative review paper provides a summary of the literature about the effects and mechanisms of PUFAs on age-related musculoskeletal diseases for the prevention and management of these diseases. Methods: Web of Science, PubMed, Science Direct, and Scopus databases have been searched to select the relevant literature on epidemiological, cellular, and animal experiments and clinical evidence in recent decades with keywords "polyunsaturated fatty acids", "PUFAs", "omega-3", "omega-6", "musculoskeletal diseases", "sarcopenia", "osteoporosis", "osteoarthritis", and so on. Results: PUFAs could prevent and treat age-related musculoskeletal diseases (sarcopenia, osteoporosis, and osteoarthritis) by reducing oxidative stress and inflammation and controlling the growth, differentiation, apoptosis, and autophagy of cells. This review paper provides comprehensive evidence of PUFAs on age-related musculoskeletal diseases, which will be helpful for exploitation into functional foods and drugs for their prevention and treatment. Conclusions: PUFAs could play an important role in the prevention and treatment of sarcopenia, osteoporosis, and osteoarthritis.

Dietary inflammatory index could increase the risk of sarcopenia in patients with chronic kidney disease

Using a system that incorporates a variety of food items rather than focusing on individual components can aid in assessing the inflammatory effects of a diet on disease outcomes such as chronic kidney disease (CKD). Therefore, we decided to investigate the association between dietary inflammatory index (DII) and the risk of protein-energy wasting (PEW) and sarcopenia in patients with CKD. In this cross-sectional study, 109 patients with CKD were selected from two clinics in Shiraz, Iran. The intake of individuals' diets was recorded using a validated 168-item food frequency questionnaire. Additionally, Asian Working Group for Sarcopenia (AWGS) guidelines were utilized to evaluate muscles' strength, mass, and function. Also, four International Society of Renal Nutrition and Metabolism (ISRNM) criteria (body mass index, intake of protein, albumin, and urine creatinine) were used  to diagnose PEW. Logistic regression was used to assess the association between DII and sarcopenia as well as PEW. The results showed that the intake of saturated fatty acids, trans fatty acids, niacin, beta-carotene, and vitamin C was significantly different between lower and higher DII groups. In the univariate model, higher odds of sarcopenia was observed by each unit increase in DII (odds ratio (OR) = 1.379, 95% confidence interval (CI): 1.042-1.824) and age (OR = 1.073, 95% CI: 1.017-1.132). Additionally, in the multivariate model, the association between DII and age with odds of sarcopenia remained significant (DII: OR = 1.379, 95% CI: 1.030-1.846 and age: OR = 1.063, 95% CI: 1.007-1.121). The current study suggests the possible role of pro-inflammatory foods in worsening muscle health, specifically sarcopenia, in CKD patients. Future longitudinal studies may reveal the causative nature of these correlations.

Underlying Mechanisms of the Protective Effects of Lifestyle Factors On Age-Related Diseases

The rise in life expectancy has significantly increased the occurrence of age-related chronic diseases, leading to escalating expenses for both society and individuals. Among the main factors influencing health and lifespan, lifestyle takes a forefront position. Specifically, nutrition, mental activity, and physical exercise influence the molecular and functional mechanisms that contribute to the prevention of major age-related diseases. Gaining deeper insights into the mechanisms that drive the positive effects of healthy lifestyles is valuable for creating interventions to prevent or postpone the development of chronic degenerative diseases. This review summarizes the main mechanisms that underlie the positive effect of lifestyle factors in counteracting the major age-related diseases involving brain health, musculoskeletal function, cancer, frailty, and cardiovascular diseases, among others. This knowledge will help to identify high-risk populations for targeted intervention trials and discover new biomarkers associated with healthy aging.

The Combination of Lactoferrin and Creatine Ameliorates Muscle Decay in a Sarcopenia Murine Model

BACKGROUND

Sarcopenia is an age-related condition characterized by progressive loss of muscle mass, strength, and function. The occurrence of sarcopenia has a huge impact on physical, psychological, and social health. Therefore, the prevention and treatment of sarcopenia is becoming an important public health issue.

METHOD

35 six-week-old male C57BL/6 mice were randomly divided into five groups, one of which served as a control group, while the rest of the groups were constructed as a model of sarcopenia by intraperitoneal injection of D-galactose. The intervention with lactoferrin, creatine, and their mixtures, respectively, was carried out through gavage for 8 weeks. Muscle function was assessed based on their endurance, hanging time, and grip strength. The muscle tissues were weighed to assess the changes in mass, and the muscle RNA was extracted for myogenic factor expression and transcriptome sequencing to speculate on the potential mechanism of action by GO and KEGG enrichment analysis.

RESULT

The muscle mass (lean mass, GAS index), and muscle function (endurance, hanging time, and grip strength) decreased, and the size and structure of myofiber was smaller in the model group compared to the control group. The intervention with lactoferrin and creatine, either alone or combination, improved muscle mass and function, restored muscle tissue, and increased the expression of myogenic regulators. The combined group demonstrated the most significant improvement in these indexes. The RNA-seq results revealed enrichment in the longevity-regulated pathway, MAPK pathway, focal adhesion, and ECM-receptor interaction pathway in the intervention group. The intervention group may influence muscle function by affecting the proliferation, differentiation, senescence of skeletal muscle cell, and contraction of muscle fiber. The combined group also enriched the mTOR-S6K/4E-BPs signaling pathway, PI3K-Akt signaling pathway, and energy metabolism-related pathways, including Apelin signaling, insulin resistance pathway, and adipocytokine signaling pathway, which affect energy metabolism in muscle.

CONCLUSIONS

Lactoferrin and creatine, either alone or in combination, were found to inhibit the progression of sarcopenia by influencing the number and cross-sectional area of muscle fibers and muscle protein synthesis. The combined intervention appears to exert a more significant effect on energy metabolism.

Associations of CBC-Derived inflammatory indicators with sarcopenia and mortality in adults: evidence from Nhanes 1999 ∼ 2006

BACKGROUND

It has been proposed that inflammation plays a role in the development of sarcopenia. This study aimed to investigate the links of complete blood cell count (CBC) parameters and CBC-derived inflammatory indicators with sarcopenia and mortality.

METHODS

Data pertaining to sarcopenia were extracted from the 1999-2006 National Health and Nutrition Examination Survey (NHANES), and mortality events were ascertained through the National Death Index up to December 31, 2019. The CBC-derived inflammatory indicators assessed in this study included the neutrophil-to-lymphocyte ratio (NLR), derived neutrophil-to-lymphocyte ratio (dNLR), monocyte-to-lymphocyte ratio (MLR), neutrophil-monocyte to lymphocyte ratio (NMLR), systemic inflammatory response index (SIRI), and systemic immune-inflammation index (SII). The prognostic significance of these CBC-derived inflammatory indicators was evaluated using the random survival forests (RSF) analysis.

RESULTS

The study encompassed a cohort of 12,689 individuals, among whom 1,725 were diagnosed with sarcopenia. Among individuals with sarcopenia, 782 experienced all-cause mortality, and 195 succumbed to cardiovascular causes. Following adjustment for confounding variables, it was observed that elevated levels of NLR, dNLR, NMLR, SIRI, and SII were associated with an increased prevalence of sarcopenia. Among participants with sarcopenia, those in the highest quartile of NLR (HR = 1.336 [1.095-1.631]), dNLR (HR = 1.274 [1.046-1.550]), MLR (HR = 1.619 [1.290-2.032]), NMLR (HR = 1.390 [1.132-1.707]), and SIRI (HR = 1.501 [1.210-1.862]) exhibited an elevated risk of all-cause mortality compared to those in the lowest quartile of these inflammation-derived indicators. These associations were similarly observed in cardiovascular mortality (HR = 1.874 [1.169-3.003] for MLR, HR = 1.838 [1.175-2.878] for SIRI). The RSF analysis indicated that MLR exhibited the highest predictive power for both all-cause and cardiovascular mortality among individuals with sarcopenia.

CONCLUSIONS

Our findings underscore the association between CBC-derived inflammatory indicators and mortality in adults with sarcopenia. Of note, MLR emerged as the most robust predictor of all-cause and cardiovascular mortality in this population.

Chimeric Cell Therapies as a Novel Approach for Duchenne Muscular Dystrophy (DMD) and Muscle Regeneration

Chimerism-based strategies represent a pioneering concept which has led to groundbreaking advancements in regenerative medicine and transplantation. This new approach offers therapeutic potential for the treatment of various diseases, including inherited disorders. The ongoing studies on chimeric cells prompted the development of Dystrophin-Expressing Chimeric (DEC) cells which were introduced as a potential therapy for Duchenne Muscular Dystrophy (DMD). DMD is a genetic condition that leads to premature death in adolescent boys and remains incurable with current methods. DEC therapy, created via the fusion of human myoblasts derived from normal and DMD-affected donors, has proven to be safe and efficacious when tested in experimental models of DMD after systemic-intraosseous administration. These studies confirmed increased dystrophin expression, which correlated with functional and morphological improvements in DMD-affected muscles, including cardiac, respiratory, and skeletal muscles. Furthermore, the application of DEC therapy in a clinical study confirmed its long-term safety and efficacy in DMD patients. This review summarizes the development of chimeric cell technology tested in preclinical models and clinical studies, highlighting the potential of DEC therapy in muscle regeneration and repair, and introduces chimeric cell-based therapies as a promising, novel approach for muscle regeneration and the treatment of DMD and other neuromuscular disorders.

Bibliometric and scientometric analysis on biomarkers and molecular mechanisms for physical frailty and sarcopenia

Introduction

The influence of physical frailty and sarcopenia (PFS) on the well-being of older people and continuous pressure on the healthcare systems has prompted a research on the pathophysiology and molecular mechanisms of these conditions. Nonetheless some biomarkers have been suggested as potential markers for PFS none of them have been shown to highlight the complex nature of PFS, which reveals that there is a need for an understanding of the possible biomarker candidates. The aim of this study was to identify the current research hotspots, status, and trends in the field of biomarkers and molecular mechanisms for PFS.

Methods

The bibliometric and scientometric analyses were performed using VOSviewer (version 1.6.18) and open source software platform Cytoscape v.3.9 (for visualizing and constructing a network of keywords). Data of publications (from 1997 to 2023) related to biomarkers and molecular mechanisms of PFS were obtained (in May 2023) from the database of Science Citation Index Expanded of Web of Science, Scopus, and PubMed. The keywords obtained from the Scopus database were used to perform a meaningful keyword analysis. A network of keyword relationships was build using Cytoscape.

Results

In this study, we present biomarker keywords for PFS in relation to other keywords potentially designating processes and mechanisms and reveal the biomarker identities and current contexts in which these biomarker identities are discussed.

Conclusions

Over recent years, scientific interest in the field of PFS has increased and focused on the inflammatory process and probably will be concentrated on myokines (such as cytokines and small proteins) that are synthetized and released by skeletal muscles in response to physical activity. Moreover, proteomic and genetic markers are deeply involved in PFS.

A bibliometric analysis of inflammation in sarcopenia from 2007 to 2022

OBJECTIVE

In recent years, the impact of inflammation regulation on the progression of sarcopenia has garnered significant attention in research. However, there has been a lack of bibliometric analysis on the literature pertaining to inflammation in sarcopenia. This study was designed for the purpose of exploring the current research trends in this field as well as general situations and hot spots through bibliometric analysis.

METHODS

Searches were performed on the Web of Science Core Collection for articles related to inflammation in sarcopenia from 2007 to 2022, and selected in compliance with PRISMA guidelines. A variety of data were analyzed and visualized using VOSviewer and CiteSpace, including countries, institutions, authors, keywords, journals, and publications.

RESULTS

1833 articles were obtained in the last 16 years in all. The number of publications and citations increased from 2007 to 2022, with a notable rise occurring after 2016. Based on the results, the United States, the University of Melbourne, Nutrients, and Marzetti Emanuele were the most productive countries, institutions, journals, and authors, respectively. The primary keywords were oxidative stress and insulin resistance, and the burst detection analysis of keywords found that there is a possibility that future research will focus on "Inflammatory Bowel Disease".

CONCLUSION

This is the first bibliometric analysis of inflammation in sarcopenia. The interaction between oxidative stress, insulin resistance and inflammation in sarcopenia is regarded as the current research priorities. As sarcopenia becomes more prevalent, a focus will be placed on determining the molecular mechanisms and therapeutic targets for regulating inflammation to intervene in sarcopenia.

Pretreatment Masseter Muscle Volume Predicts Survival in Locally Advanced Nasopharyngeal Carcinoma Patients Treated with Concurrent Chemoradiotherapy

BACKGROUND AND PURPOSE

Muscle loss is a significant indicator of cancer cachexia and is associated with a poor prognosis in cancer patients. Given the absence of comparable studies, the current retrospective study sought to examine the correlation between the total masseter muscle volume (TMMV) before treatment and the survival outcomes in locally advanced nasopharyngeal cancer (LA-NPC) patients who received definitive concurrent chemoradiotherapy (CCRT).

METHODS

A three-dimensional segmentation model was used to determine the TMMV for each patient by analyzing pre-CCRT magnetic resonance imaging. The optimal TMMV cutoff values were searched using receiver operating characteristic (ROC) curve analyses. The primary and secondary endpoints were the relationship between the pre-CCRT TMMV measures and overall survival (OS) and progression-free survival (PFS), respectively.

RESULTS

Ninety-seven patients were included in this study. ROC curve analyses revealed 38.0 cc as the optimal TMMV cutoff: ≤38.00 cc (n = 42) and >38.0 cc (n = 55). Comparisons between the two groups showed that the TMMV>38.0 cc group had significantly longer PFS [Not reached (NR) vs. 28; p < 0.01] and OS (NR vs. 71; p < 0.01) times, respectively. The results of the multivariate analysis demonstrated that the T-stage, N-stage, number of concurrent chemotherapy cycles, and TMMV were independent associates of PFS (p < 0.05 for each) and OS (p < 0.05 for each) outcomes, respectively.

CONCLUSION

The findings of the current retrospective research suggest that pretreatment TMMV is a promising indicator for predicting survival outcomes in LA-NPC patients receiving definitive CCRT.

Sex-Specific Associations between Serum IL-16 Levels and Sarcopenia in Older Adults

Epidemiological studies of older adults have suggested a differential sex-specific prevalence of sarcopenia, which is a condition characterized by a progressive loss of skeletal muscle mass and function. Recently, we collected serum samples from 80 fully evaluated older adults and identified CXCL12α as a sex-independent serum marker of sarcopenia. Here, we used this serum collection to find potential sex-specific serum markers via the simultaneous quantification of 34 inflammatory cytokines/chemokines. The appendicular skeletal muscle index (ASMI) was used as a decisive criterion for diagnosing sarcopenia. A Pearson correlation analysis revealed a negative correlation between ASMI and serum IL-16 in females only (p = 0.021). Moreover, women with sarcopenia exhibited significantly higher IL-16 (p = 0.025) serum levels than women in a control group. In contrast, males with sarcopenia had lower IL-16 (p = 0.013) levels than males in a control group. The further use of Fisher's exact test identified obesity (p = 0.027) and high serum levels of IL-16 (p = 0.029) as significant risk factors for sarcopenia in females. In male older adults, however, malnutrition (p = 0.028) and low serum levels of IL-16 (p = 0.031) were the most significant risk factors for sarcopenia. The differential sex-specific associations of IL-16 in older adults may contribute to the development of more precise regression models for future research and elucidate the role of IL-16 in the progression of sarcopenic obesity.

Mechanisms Underlying the Effects of the Green Tea Polyphenol EGCG in Sarcopenia Prevention and Management

Sarcopenia is prevalent among the older population and severely affects human health. Tea catechins may benefit for skeletal muscle performance and protect against secondary sarcopenia. However, the mechanisms underlying their antisarcopenic effect are still not fully understood. Despite initial successes in animal and early clinical trials regarding the safety and efficacy of (-)-epigallocatechin-3-gallate (EGCG), a major catechin of green tea, many challenges, problems, and unanswered questions remain. In this comprehensive review, we discuss the potential role and underlying mechanisms of EGCG in sarcopenia prevention and management. We thoroughly review the general biological activities and general effects of EGCG on skeletal muscle performance, EGCG's antisarcopenic mechanisms, and recent clinical evidence of the aforesaid effects and mechanisms. We also address safety issues and provide directions for future studies. The possible concerted actions of EGCG indicate the need for further studies on sarcopenia prevention and management in humans.

The effects of nutritional supplementation on older sarcopenic individuals who engage in resistance training: a meta-analysis

Objective

Sarcopenia is a typical age-related disorder characterized by loss of muscle mass, strength, and physical function. Resistance training has a noticeable effect on sarcopenia, but there is no consensus on whether nutritional supplements can boost this effect. We conducted a meta-analysis of relevant literature to investigate the therapeutic effect of resistance training combined with nutrition intervention on sarcopenia compared with resistance training alone.

Methods

Cochrane Library, PubMed, Web of Science, Embase, Sinomed, CNKI, VIP, and Wanfang Data were searched for relevant studies on resistance training combined with nutritional intervention for aging adults with sarcopenia. The retrieval period ranged from the inception of the databases to May 24, 2022. Literature screening and information extraction were performed by two researchers. The Physiotherapy Evidence Database (PEDro) scale was adopted for literature quality evaluation and Stata 15.0 software for analysis.

Results

Twelve clinical trials were included, involving 713 older adults diagnosed with sarcopenia, of whom 361 were assigned to the experimental group and 352 to the control group. Compared with the control group, grip strength of the experimental group was substantially elevated [WMD = 1.87, 95% CI (0.01, 3.74), P = 0.049]. Subgroup analysis demonstrated that vitamin D and protein increased grip strength and gait speed. There were no significant improvement in grip strength and gait speed in the protein and vitamin D free subgroup.

Conclusions

This meta-analysis demonstrated that resistance training combined with additional nutritional supplementation, especially compound nutritional supplements that included protein and vitamin D, might further enhance grip strength rather than muscle mass in older adults with sarcopenia.

Systematic review registration

https://www.crd.york.ac.uk/PROSPERO/, identifier: CRD42022346734.

Sarcopenia: Molecular regulatory network for loss of muscle mass and function

Skeletal muscle is the foundation of human function and plays a key role in producing exercise, bone protection, and energy metabolism. Sarcopenia is a systemic disease, which is characterized by degenerative changes in skeletal muscle mass, strength, and function. Therefore, sarcopenia often causes weakness, prolonged hospitalization, falls and other adverse consequences that reduce the quality of life, and even lead to death. In recent years, sarcopenia has become the focus of in-depth research. Researchers have suggested some molecular mechanisms for sarcopenia according to different muscle physiology. These mechanisms cover neuromuscular junction lesion, imbalance of protein synthesis and breakdown, satellite cells dysfunction, etc. We summarize the latest research progress on the molecular mechanism of sarcopenia in this review in order to provide new ideas for future researchers to find valuable therapeutic targets and develop relevant prevention strategies.

[Physical activity in sarcopenia: rehabilitation approaches in prevention and treatment of age-related muscle disorders]

Sarcopenia is a widespread condition in the elderly people, that occurs as a result of impaired muscle structure and function and is significantly associated with reduced quality and time of life. This review represents current approaches to the diagnosis of sarcopenia with reference to recent European and Asian consensus. They include rules for the evaluation of the main muscle strength and function tests (hand dynamometry, sit-to-stand test, 6-minute walk test, physical performance battery tests, etc.), physical and instrumental methods of muscle mass analysis (densitometry, bioimpedance analysis, magnetic resonance imaging). Furthermore, the pathogenetic relationship between the lack of physical activity and muscle dysfunction in elderly people is broached, including in particular the role of myostatin, interleukin-6, somatotropin and insulin resistance. The article represents possibilities of impact of aerobic, strength and neuromuscular physical exercises on prevention and correction of sarcopenic changes in different age groups based on the analysis of current clinical studies.

Exercise and mitochondrial mechanisms in patients with sarcopenia

Sarcopenia is a severe loss of muscle mass and functional decline during aging that can lead to reduced quality of life, limited patient independence, and increased risk of falls. The causes of sarcopenia include inactivity, oxidant production, reduction of antioxidant defense, disruption of mitochondrial activity, disruption of mitophagy, and change in mitochondrial biogenesis. There is evidence that mitochondrial dysfunction is an important cause of sarcopenia. Oxidative stress and reduction of antioxidant defenses in mitochondria form a vicious cycle that leads to the intensification of mitochondrial separation, suppression of mitochondrial fusion/fission, inhibition of electron transport chain, reduction of ATP production, an increase of mitochondrial DNA damage, and mitochondrial biogenesis disorder. On the other hand, exercise adds to the healthy mitochondrial network by increasing markers of mitochondrial fusion and fission, and transforms defective mitochondria into efficient mitochondria. Sarcopenia also leads to a decrease in mitochondrial dynamics, mitophagy markers, and mitochondrial network efficiency by increasing the level of ROS and apoptosis. In contrast, exercise increases mitochondrial biogenesis by activating genes affected by PGC1-ɑ (such as CaMK, AMPK, MAPKs) and altering cellular calcium, ATP-AMP ratio, and cellular stress. Activation of PGC1-ɑ also regulates transcription factors (such as TFAM, MEFs, and NRFs) and leads to the formation of new mitochondrial networks. Hence, moderate-intensity exercise can be used as a non-invasive treatment for sarcopenia by activating pathways that regulate the mitochondrial network in skeletal muscle.

Inflammaging: Implications in Sarcopenia

In a world in which life expectancy is increasing, understanding and promoting healthy aging becomes a contemporary demand. In the elderly, a sterile, chronic and low-grade systemic inflammation known as "inflammaging" is linked with many age-associated diseases. Considering sarcopenia as a loss of strength and mass of skeletal muscle related to aging, correlations between these two terms have been proposed. Better knowledge of the immune system players in skeletal muscle would help to elucidate their implications in sarcopenia. Characterizing the activators of damage sensors and the downstream effectors explains the inference with skeletal muscle performance. Sarcopenia has also been linked to chronic diseases such as diabetes, metabolic syndrome and obesity. Implications of inflammatory signals from these diseases negatively affect skeletal muscle. Autophagic mechanisms are closely related with the inflammasome, as autophagy eliminates stress signaling sent by damage organelles, but also acts with an immunomodulatory function affecting immune cells and cytokine release. The use of melatonin, an antioxidant, ROS scavenger and immune and autophagy modulator, or senotherapeutic compounds targeting senescent cells could represent strategies to counteract inflammation. This review aims to present the many factors regulating skeletal muscle inflammaging and their major implications in order to understand the molecular mechanisms involved in sarcopenia.

The Inverse Association of Sarcopenia and Protein-Source Food and Vegetable Intakes in the Korean Elderly: The Korean Frailty and Aging Cohort Study

The aging population contributes to increasing economic and social burden worldwide. Sarcopenia, an age-related degenerative disease and progressive disorder, is characterized by a reduction in skeletal muscle mass and function. This study aims to assess the association between dietary factors and sarcopenia in the Korean elderly using nationwide data. A total of 801 subjects aged 70–84 years were included in this analysis. Subjects were divided into two groups: sarcopenic and nonsarcopenic groups according to the sarcopenia criteria established by the Asian Working Group for Sarcopenia. Nutrient and food intakes were assessed using a 24-h recall method. Logistic regression analysis was used to assess the association between sarcopenia and food group and nutrient intakes. In the multivariable models, the meat/fish/egg/legume food group, vegetable group, and total food intake were inversely associated with the prevalence of sarcopenia. The high intakes of energy, carbohydrate, protein, fiber, zinc, carotene, and vitamin B₆ were associated with the lower prevalence of sarcopenia. Therefore, consuming sufficient nutrients through various protein source foods and vegetables will help prevent sarcopenia in the Korean elderly.

Sarcopenia and blood albumin: A systematic review with meta-analysis

Sarcopenia is characterized by loss of muscle mass during aging, which can have consequences for the individuals’ health. There are many ways to detect it, among them, with the use of blood biomarkers such as albumin, although the association between the two has not been confirmed yet. This review synthesizes the knowledge on the association between sarcopenia and serum albumin among elderly individuals through a systematic review and meta-analysis focused on the etiology and risk factors. We used the Joanna Briggs Institute software for the review and conducted a search in MEDLINE, Embase, CINAHL, and LILACS databases while two reviewers conducted an independent manual search. EpiDat, version 3.1 was used for the meta-analysis; mean differences with the albumin scores disaggregated by sarcopenia were analyzed by the random-effects model. The degree of heterogeneity was assessed with the DerSimonian and Laird Q test. We analyzed 630 articles and finally included 14 in the review. Higher blood albumin levels were found in the meta-analysis, which was statistically significant among the elderly adults who did not present sarcopenia compared to those who did. Although there are studies exploring the association between albumin and sarcopenia, there is a need to continue evaluating its association with biological markers and comparing them to verify which can be used to detect sarcopenia among the elderly.

Identifying and Managing Malnutrition, Frailty and Sarcopenia in the Community: A Narrative Review

Malnutrition, frailty and sarcopenia are becoming increasingly prevalent among community-dwelling older adults; yet are often unidentified and untreated in community settings. There is an urgent need for community-based healthcare professionals (HCPs) from all disciplines, including medicine, nursing and allied health, to be aware of, and to be able to recognise and appropriately manage these conditions. This paper provides a comprehensive overview of malnutrition, frailty and sarcopenia in the community, including their definitions, prevalence, impacts and causes/risk factors; and guidance on how these conditions may be identified and managed by HCPs in the community. A detailed description of the care process, including screening and referral, assessment and diagnosis, intervention, and monitoring and evaluation, relevant to the community context, is also provided. Further research exploring the barriers/enablers to delivering high-quality nutrition care to older community-dwelling adults who are malnourished, frail or sarcopenic is recommended, to inform the development of specific guidance for HCPs in identifying and managing these conditions in the community.