Prevalence, incidence, and clinical impact of sarcopenia: facts, numbers, and epidemiology-update 2014

Predictors of Sarcopenia in an Obese Asian Population

Sarcopenia is associated with obesity and might also be responsible for other disorders. Here, we investigated the prevalence of sarcopenia and its predictors in obese subjects. Subjects who underwent a medical health checkup and living-related liver donors were recruited. Obesity was defined as body mass index (BMI) ≥25 kg/m2. Muscle mass was assessed using computed tomography at the 3rd lumbar vertebra. The lowest quartile of the lumbar skeletal muscle index (LSMI) was considered sarcopenia. Among 466 obese subjects, 53 (11.4%) had sarcopenia. Subjects with sarcopenia were significantly older (mean 66.6 vs. 53.3 years) and had a significantly higher prevalence of hypertension (62.3 vs. 46.0%) and diabetes (45.3 vs. 31.0%), higher fibrosis-4 (FIB-4) index (mean 1.57 vs. 1.16), and higher atherosclerotic cardiovascular disease (ASCVD) risk score (mean 22.86% vs. 11.15%), whereas they had a significantly lower prevalence of female gender (13.2% vs. 27.8%), lower BMI (mean 26.4 vs. 27.4 kg/m2), and lower LSMI (mean 43 vs. 56 cm2/m2) than subjects without sarcopenia (all P < 0.05). On multivariate analysis, higher BMI (odd ratio [OR] = 0.599, P = 0.001) was independently associated with a reduced risk of sarcopenia, whereas higher ASCVD risk scores (OR = 1.045, P < 0.001) were independently associated with an increased risk of sarcopenia. Sarcopenia is significantly associated with lower BMI and higher cardiovascular risk in an obese Asian population.

The long-term prognostic factors in hemodialysis patients with acute coronary syndrome: perspectives from sarcopenia and malnutrition

Hemodialysis (HD) patients tend to have sarcopenia and malnutrition, and both conditions are related to poor prognosis in the cardiovascular disease that often accompanies HD. However, the impact of sarcopenia or malnutrition on the long-term prognosis of HD patients undergoing percutaneous coronary intervention (PCI) for acute coronary syndrome (ACS) remains unclear. We analyzed 1,605 consecutive patients with ACS who had undergone PCI at a single center between January 2009 and December 2014. We evaluated all-cause mortality and prognosis-associated factors, including sarcopenia/malnutrition-related factors such as the Geriatric Nutritional Risk Index (GNRI), and Skeletal Muscle Mass Index (SMI). After exclusions, 1461 patients were enrolled, and 58 (4.0%) were on HD. The HD group had lower levels of SMI and GNRI than non-HD group, and had worse in-hospital prognosis. Moreover, HD group had a significant higher mortality in the long-term follow-up [median follow-up period: 1219 days; Hazard Ratio (HR) = 4.09, p < 0.001]. After adjusting the covariates, SMI and GNRI were the factors associated with all-cause mortality in all patients [SMI: adjusted HR (aHR) = 2.39, p = 0.036; GNRI: aHR = 2.21, p = 0.006]; however, these findings were not observed among HD patients with ACS, and only diabetes was significantly associated with all-cause mortality (diabetes: aHR = 3.50, p = 0.031). HD patients with ACS had a significantly higher rate of in-hospital and long-term mortality than non-HD patients. Although sarcopenia and malnutrition were related to mortality and were more common in HD patients, sarcopenia and malnutrition had a lower impact than diabetes on the long-term prognosis of HD patients with ACS.

Sarcopenia prevalence and associated factors among older Chinese population: Findings from the China Health and Retirement Longitudinal Study

Sarcopenia a recognised geriatric syndrome. This study aims to evaluate the prevalence of possible sarcopenia, sarcopenia and severe sarcopenia among older Chinese adults and to identify any associated factors for possible sarcopenia according to the updated diagnostic criteria of the Asian Working Group for Sarcopenia 2019 (AWGS 2019). We used data from the China Health and Retirement Longitudinal Study (CHARLS). The main outcome of this study was possible sarcopenia. Handgrip strength was measured via a dynamometer. The muscle mass was estimated by anthropometric measures. Physical performance was measured by 5-time chair stand test and gait speed test. A multivariate logistic regression model with stepwise method was employed to identify factors associated with possible sarcopenia. A total of 6172 participants aged 60-94 years were included. The prevalence of possible sarcopenia, sarcopenia and severe sarcopenia was 38.5%, 18.6%, and 8.0%, respectively. Age, rural area, falls, higher C-reactive protein (CRP), and chronic diseases (including hypertension, chronic lung diseases, heart disease, psychiatric disease and arthritis) were associated with a higher risk of possible sarcopenia. Conversely, alcohol consumption, higher gait speed and high levels of hemoglobin were associated with decreased risk of possible sarcopenia. However, the associations between possible sarcopenia with alcohol consumption, heart disease, psychiatric disease and hemoglobin were not significant after Bonferroni correction. Our study reported a relatively high prevalence of sarcopenia among older Chinese population, and identified a range of factors associated with sarcopenia. We also found rural elders are more vulnerable to sarcopenia than urban elders. Additionally, we discovered systemic inflammation might be one of the contributing factors between sarcopenia and related comorbidities. We believe the findings of this study would help to identify individuals at high risk of sarcopenia early and therefore implement the prevention and treatment strategies to reduce the disease burden in China.

Vitamin D Deficiency is Associated with Handgrip Strength, Nutritional Status and T2DM in Community-Dwelling Older Mexican Women: A Cross-Sectional Study

The aim of this study was to evaluate the association between handgrip strength, nutritional status and vitamin D deficiency in Mexican community-dwelling older women. A cross sectional study in women ≥ 60 years-old was performed. Plasma 25-hydroxyvitamin D (25(OH)D) concentrations were measured by a quantitative immunoassay technique. Handgrip strength was assessed using a dynamometer, while nutritional status was assessed through the Full Mini Nutritional Assessment (Full-MNA). A total of 116 women participated in the study, their mean age was 70.3 ± 5.8 years; 49.1% of the study group had plasma 25(OH)D levels lower than 40 nmol/L [16 ng/mL]. Meanwhile, 28.45% of participants had low handgrip strength (<16 kg), and 23.1% were identified at risk of malnutrition/malnourished according with Full-MNA score. Women with 25(OH)D deficiency (<40 nmol/L [16 ng/mL]) were more likely to have low handgrip strength (OR = 2.64, p = 0.025) compared with those with higher 25(OH)D values. Additionally, being malnourished or at risk of malnutrition (OR = 2.53, p = 0.045) or having type 2 diabetes mellitus (T2DM) (OR = 2.92, p = 0.044) was also associated with low 25(OH)D. The prevalence of low plasma 25(OH)D concentrations was high among Mexican active older women. Low handgrip strength, being at risk of malnutrition/malnourished, or diagnosed with T2DM was also associated with Vitamin D deficiency.

Sarcopenia in Inflammatory Bowel Disease: A Narrative Overview

Malnutrition is a common condition encountered in patients with inflammatory bowel disease (IBD) and is often associated with sarcopenia (the reduction of muscle mass and strength) which is an ever-growing consideration in chronic diseases. Recent data suggest the prevalence of sarcopenia is 52% and 37% in Crohn's disease and ulcerative colitis, respectively, however it is challenging to fully appreciate the prevalence of sarcopenia in IBD. Sarcopenia is an important consideration in the management of IBD, including the impact on quality of life, prognostication, and treatment such as surgical interventions, biologics and immunomodulators. There is evolving research in many chronic inflammatory states, such as chronic liver disease and rheumatoid arthritis, whereby interventions have begun to be developed to counteract sarcopenia. The purpose of this review is to evaluate the current literature regarding the impact of sarcopenia in the management of IBD, from mechanistic drivers through to assessment and management.

A Novel Magnetic Resonance Imaging-based Lumbar Muscle Grade to Predict Health-related Quality of Life Scores Among Patients Requiring Surgery

STUDY DESIGN

Retrospective cross-sectional cohort.

OBJECTIVE

The aim of this sudy was to determine whether muscle health measurements are associated with health-related quality of life scores (HRQOLs) for patients with lumbar spine pathology.

SUMMARY OF BACKGROUND DATA

Poor muscle health has been implicated as a source of pain/dysfunction for patients with lumbar spine pathology. Our aim was to quantify the relationship using muscle health measurements and HRQOLs.

METHODS

Three hundred and eight patients were included (mean age 57.7 ± standard deviation 18.2 years' old). We randomly selected patients into a derivation cohort (200) and validation cohort (108) to create our muscle health grade. We measured muscle health by the lumbar indentation value (LIV), goutallier classification (GC), and ratio of paralumbar muscle cross-sectional area over body mass index (PL-CSA/BMI). A muscle health grade was derived based on whether a measurement showed a statistically significant impact on visual analog scale back and leg pain (VAS-leg and VAS-leg), Oswestry Disability Index (ODI), short-form 12 physical health score (SF-12 PHS), short-form 12 mental health score (SF-12 MHS) and Patient-reported Outcomes Measurement Information System (PROMIS). A variety of statistical tools were used to determine whether there was a relationship between a measurement and HRQOLs.

RESULTS

In the derivation cohort, a muscle health grade was created based on the GC and PL-CSA/BMI ratio. For patients with a GC ≤2, one point was given. For patients with a PL-CSA/BMI ≥130, one point was given. Patients with 2 points were graded as "A" and 0 or 1 point were graded "B." Within the validation cohort of patients, there was a statistically significant higher PROMIS (mean 34.5 ± standard deviation 12.6 vs. 27.6 ± 14.0, P = 0.002), ODI (38.8 ± 18.3 vs. 45.8 ± 18.1, P = 0.05) and SF-12 PHS (34.7 ± 11.3 vs. 29.1 ± 6.3, P = 0.002) for patients with a good muscle health grade of "A."

CONCLUSION

This study offers an objective measurement of muscle health that correlates with HRQOLs for patients with lumbar spine pathology.Level of Evidence: 3.

Prevalence and Related Factors of Sarcopenia in Community-dwelling Elderly with Long-term Care Insurance

BACKGROUND AND OBJECTIVE

The purpose of this investigation was to examine the prevalence, related factors, and cut-off value of body mass index for sarcopenia in community-dwelling elderly covered by long-term care insurance.

METHODS

Design was a cross-sectional study, in which113 consecutive community-dwelling elderly with long-term care insurance who underwent rehabilitation at a daycare center in Japan from January 2016 to January 2018, those who were aged ≥65 years old and could walk were included. Those in whom skeletal muscle mass index could not be measured were excluded. The determination of sarcopenia was made according to the criteria of the Asian Working Group for Sarcopenia. We analyzed the data with the unpaired t-test, χ² test, logistic regression analysis, and receiver operating characteristic curves.

RESULTS

The 99 elderly meeting the criteria were included and divided into the sarcopenia group (n=36) and no sarcopenia group (n=63). The prevalence was 36.4%. The sarcopenia group was significantly older and had lower body mass index, skeletal muscle mass index, and grip strength than the group without sarcopenia (p <0.05). Age and body mass index were extracted as significant sarcopenia- related factors (p <0.05). The cut-off value of body mass index for sarcopenia was 22.6 kg/m².

CONCLUSION

The prevalence of sarcopenia in the elderly in the long-term care insurance region was 36.4%, and age and body mass index were extracted as sarcopenia-related factors. The cut-off value of body mass index for sarcopenia was 22.6 kg/m².

Associations between Physical Function, Bone Density, Muscle Mass and Muscle Morphology in Older Men with Sarcopenia: A Pilot Study

Background and Objectives: It is thought that muscle and bone interact only on a biomechanical level, however, some research is now emerging that links bone and muscle on a cellular level. The aim of this study was to explore associations between physical function, muscle mass and bone density in community-dwelling elderly men with sarcopenia. A secondary goal was to analyze if muscle morphology was associated with bone density and physical functioning. Materials and Methods: Body composition was measured by dual-energy X-ray absorptiometry (DXA). Bone density was evaluated according to WHO criteria. Sarcopenia was diagnosed according to European Working Group on Sarcopenia in Older People (EWGSOP) criteria: low muscle mass and low muscle strength or low physical performance. Microbiopsy of musculus vastus lateralis was performed with a disposable muscle microbiopsy system. The perimeter and cross-sectional area of muscle fibers were calculated using image analysis software in whole slide images; type of fibers and their distribution were evaluated as well. Results: A total of 151 men, 60 years or older were included in this study. Mean age of the subjects was 72.9 ± 8.02 years. Sarcopenia was diagnosed in 45 (29.8%) men. Multiple significant correlations were found between bone mineral density, lean mass, appendicular lean mass, arm and leg lean mass, gait speed, balance test and handgrip strength in sarcopenic men. Lean mass was associated with femoral neck BMD (bone mineral density; r = 0.418, p = 0.006) and handgrip strength (r = 0.553, p < 0.001). In the sarcopenia group, 25 muscle biopsies were examined. In 9 sarcopenic men with T-scores equal or below -2.5, the muscle fiber area had a significant correlation with the balance test (r = 0.73, p = 0.025). Conclusions: In men with sarcopenia, low lean muscle mass was associated with low femoral neck BMD and low muscle strength. In sarcopenic men with osteoporosis, low muscle fiber area was associated with low scores in a balance test.

The longitudinal associations between bone mineral density and appendicular skeletal muscle mass in Chinese community-dwelling middle aged and elderly men

Background

The present study aimed to investigate longitudinal associations between bone mineral densities (BMDs) and appendicular skeletal muscle (ASM) mass in different regions of the body using three different indicators, in Chinese community-dwelling middle-aged and elderly men.

Methods

A total of 1,343 men aged ≥ 40 years from a Chinese community were assessed at baseline (2014-2016), one-year follow-up (2016-2017; n = 648), two-year follow-up (2017-2018; n = 407), and three-year follow up (2018-2019; n = 208). At all the four time-points, measurements included ASM mass and BMDs for all regions of the body using dual-energy X-ray absorptiometry. A questionnaire was completed by patients and biochemical markers were assessed. We applied three different indicators to define ASM mass or lean mass respectively, including the appendicular skeletal muscle index (ASM adjusted by height, ASMI, according to the Asian Working Group for Sarcopenia), skeletal muscle index (ASM adjusted by weight, SMI, according to the International Working Group on Sarcopenia), and the appendicular skeletal muscle/body mass index (ratio of ASM and Body mass index (BMI), ASM/BMI, according to the Foundation for the National Institutes of Health). After adjusting for potential confounders, the generalized additive mixed model (GAMM) was used to analyze the trend in ASM mass over time, and to test the association between ASM mass and regional and whole-body BMDs.

Results

The incidence of low lean mass was 8.2% defined by ASMI, 16.3% defined by SMI, and 8.3% defined by ASM/BMI. There was a linear relationship between BMDs and ASM mass, and ASMI, ASM/BMI, and SMI gradually decreased with time. After adjusting for covariances, GAMM analysis determined longitudinal associations between BMDs and ASM mass by three indicators respectively: the skull BMD was negatively associated with ASM mass. For each unit increase in skull BMD, ASMI decreased by 0.28 kg/m² (95% confidence interval (CI) [-0.39 to -0.16]), ASM/BMI decreased by 0.02 m² (95% CI [-0.03 to -0.00]), and SMI decreased by 0.01% (95% CI[-0.01 to -0.00]). The remaining parameters (including whole-body mean BMD, thoracic spinal BMD, lumbar spinal BMD, hip BMD, femoral neck BMD, pelvic BMD, left arm BMD, right arm BMD, left leg BMD, right leg BMD) were positively correlated with ASM mass. The ASMI increased by 3.07 kg/m²for each unit increase in the femoral neck BMD (95% CI [2.31-3.84]). The ASM/BMI increased by 0.22 m²for each unit increase in the left arm BMD (95% CI [0.12-0.33]), and the SMI increased by 0.05% per unit increase in the left arm BMD (95% CI [0.02-0.08]).

Conclusions

Compared to ASMI and ASM/BMI, SMI was more sensitive to screen for the low lean mass. Skull BMD was negatively associated with ASM mass, while BMDs throughout the rest of the body were positively correlated with ASM mass among the middle-aged and elderly Chinese men.

Sarcopenia in patients after an episode of acute decompensated heart failure: An underdiagnosed problem with serious impact

BACKGROUND & AIMS

Sarcopenia is a multifactorial syndrome resulting in a decrease in both muscle mass and function. Little is known about the prevalence and prognostic impact of sarcopenia in patients with acutely decompensated chronic heart failure (ADHF). We aimed to evaluate the prevalence (main endpoint) and impact of sarcopenia on ADHF patients.

METHODS

140 ADHF patients were enrolled between November 2014 and September 2018 in a multicenter prospective longitudinal study. A similar, independent multi-departmental cross-sectional study in 165 ADHF patients was used for external validation of prevalence data. All subjects were assessed on the European Working Group on Sarcopenia criteria.

RESULTS

Ninety-one patients (65%) had sarcopenia (vs. 53.6% in the external replication regional cohort). Patients with sarcopenia were older and more likely to have eGFR <60 ml/min/1.73 m² (p < 0.001 and p = 0.002). Sarcopenia was associated with impaired functional status [lower 6 min walking test (220 ± 108 vs. 279 ± 170, p = 0.03) and 4 m gait speed (0.56 ± 0.24 vs. 0.80 ± 0.37, p < 0.001)] and autonomy [Instrumental activities of daily living: 6.7 ± 1.4 vs. 7.3 ± 1.2, p = 0.005]. Over up to 4 years' follow-up, 30 cardiovascular (CV) deaths and 42 non-CV deaths occurred. In a multivariable analysis, sarcopenia was associated with time to first non-CV hospitalization (hazard ratio 1.93; 95% confidence interval 1.14-3.24; p = 0.014) but not with any other hospitalization, any mortality endpoint, or a composite endpoint of CV death and HF hospitalization.

CONCLUSIONS

The prevalence of sarcopenia in ADHF patients is high and associated with greater risk of non-CV hospitalizations, highlighting the importance of identifying and managing the condition in a multidisciplinary approach.

CLINICAL TRIAL REGISTRATION

NCT03153774.

Role of hormones in sarcopenia

Aging involves numerous changes in body composition that include a decrease in skeletal muscle mass. The gradual reduction in muscle mass is associated with a simultaneous decrease in muscle strength, which leads to reduced mobility, fragility and loss of independence. This process called sarcopenia is secondary to several factors such as sedentary lifestyle, inadequate nutrition, chronic inflammatory state and neurological alterations. However, the endocrine changes associated with aging seem to be of special importance in the development of sarcopenia. On one hand, advancing age is associated with a decreased secretion of the main hormones that stimulate skeletal muscle mass and function (growth hormone, insulin-like growth factor 1 (IGFI), testosterone and estradiol). On the other hand, the alteration of the IGF-I signaling along with decreased insulin sensitivity also have an important impact on myogenesis. Other hormones that decline with aging such as the adrenal-derived dehydroepiandrosterone, thyroid hormones and vitamin D seem to also be involved in sarcopenia. Adipokines released by adipose tissue show important changes during aging and can affect muscle physiology and metabolism. In addition, catabolic hormones such as cortisol and angiotensin II can accelerate aged-induced muscle atrophy, as they are involved in muscle wasting and their levels increase with age. The role played by all of these hormones and the possible use of some of them as therapeutic tools for treating sarcopenia will be discussed.

Can physical activity levels and relationships with energy expenditure change the clinical aspects of sarcopenia and perceptions of falls among elderly women? Observational cross-sectional study

BACKGROUND

Physical activity (PA) is an effective strategy for managing sarcopenia in the elderly, but few studies have addressed PA levels regarding age-related changes.

OBJECTIVE

To ascertain the effects of elderly women's PA levels on sarcopenia, physical performance, handgrip strength and perception of the risk of falling, and their relationship with energy expenditure.

DESIGN AND SETTING

Observational cross-sectional study conducted in the southern region of the city of São Paulo, Brazil.

METHODS

Forty-seven elderly women were evaluated and divided into three groups: low PA (n = 13); moderate PA (n = 16); and high PA (n = 18). Their PA levels were investigated through the International Physical Activity Questionnaire (IPAQ); sarcopenia index, through dual-energy radiological absorptiometry; physical performance through the Timed Up & Go test; handgrip strength, using a digital dynamometer; and perception of the risk of falling, through the Fall Risk Awareness Questionnaire.

RESULTS

High PA level indicated higher skeletal muscle mass index, physical performance and IPAQ score, compared with low and moderate PA levels. Multiple linear regression analysis showed that higher IPAQ energy expenditure at high and moderate PA levels was a good predictor of higher physical performance and increased perception of the risk of falling.

CONCLUSION

Elderly women classified as having high PA level showed improvements in sarcopenia, handgrip strength, physical performance and perception of the risk of falling. The IPAQ energy expenditure of the elderly women with high and moderate PA levels was a good predictor of physical performance and improved perception of the risk of falling.

Skeletal Muscle Health and Cognitive Function: A Narrative Review

Sarcopenia is the loss of skeletal muscle mass and function with advancing age. It involves both complex genetic and modifiable risk factors, such as lack of exercise, malnutrition and reduced neurological drive. Cognitive decline refers to diminished or impaired mental and/or intellectual functioning. Contracting skeletal muscle is a major source of neurotrophic factors, including brain-derived neurotrophic factor, which regulate synapses in the brain. Furthermore, skeletal muscle activity has important immune and redox effects that modify brain function and reduce muscle catabolism. The identification of common risk factors and underlying mechanisms for sarcopenia and cognition may allow the development of targeted interventions that slow or reverse sarcopenia and also certain forms of cognitive decline. However, the links between cognition and skeletal muscle have not been elucidated fully. This review provides a critical appraisal of the literature on the relationship between skeletal muscle health and cognition. The literature suggests that sarcopenia and cognitive decline share pathophysiological pathways. Ageing plays a role in both skeletal muscle deterioration and cognitive decline. Furthermore, lifestyle risk factors, such as physical inactivity, poor diet and smoking, are common to both disorders, so their potential role in the muscle-brain relationship warrants investigation.

Calf Circumference as an Optimal Choice of Four Screening Tools for Sarcopenia Among Ethnic Chinese Older Adults in Assisted Living

Introduction

Sarcopenia is highly prevalent among residents of assisted-living facilities. However, the optimal screening tools are not clear. Therefore, we compared the performance of four recommended screening tools for predicting sarcopenia.

Methods

The study recruited 177 people over 65 years of age in assisted-living facilities. Appendicular muscle mass index was measured using bioelectrical impedance analysis. Calf circumference (CC), handgrip, six-meters walking speed, and screening questionnaires including SARC-CalF, SARC-F and 5-item Mini Sarcopenia Risk Assessment (MSRA-5) were evaluated. The diagnosis criteria for sarcopenia were based on the Asian Working Group for Sarcopenia 2019 consensus. The area under the receiver operating characteristic curves (AUC) was used to contrast the diagnostic accuracy of screening tools.

Results

The prevalence of sarcopenia was 52.7% among men and 51.2% among women. After adjusting for age, sex, body mass index and SARC-CalF score, CC remained significantly associated with sarcopenia in logistic regression analysis. The prediction model for sarcopenia based on CC alone had the highest accuracy compared to SARC-CalF, MSRA-5 and SARC-F (AUC, 0.819 vs 0.734 vs 0.600 vs 0.576; sensitivity/specificity, 80.4%/71.8% vs 38.0%/80.0% vs 60.7%/54.2% vs 10.9%/91.8%). Differences in AUCs between the prediction models were statistically significant (CC vs. SARC-CalF, P = 0.0181; SARC-CalF vs. MSRA-5, P = 0.0042). Optimal cutoff values for predicting sarcopenia were CC <34 cm in men and <33 cm in women.

Conclusion

To predict sarcopenia based on low CC alone is accurate, easy and inexpensive for use in assisted-living facility settings. Further validation studies in different populations are suggested.

The Interplay between Mitochondrial Morphology and Myomitokines in Aging Sarcopenia

Sarcopenia is a chronic disease characterized by the progressive loss of skeletal muscle mass, force, and function during aging. It is an emerging public problem associated with poor quality of life, disability, frailty, and high mortality. A decline in mitochondria quality control pathways constitutes a major mechanism driving aging sarcopenia, causing abnormal organelle accumulation over a lifetime. The resulting mitochondrial dysfunction in sarcopenic muscles feedbacks systemically by releasing the myomitokines fibroblast growth factor 21 (FGF21) and growth and differentiation factor 15 (GDF15), influencing the whole-body homeostasis and dictating healthy or unhealthy aging. This review describes the principal pathways controlling mitochondrial quality, many of which are potential therapeutic targets against muscle aging, and the connection between mitochondrial dysfunction and the myomitokines FGF21 and GDF15 in the pathogenesis of aging sarcopenia.

The endocrinology of sarcopenia and frailty

Sarcopenia describes low muscle mass and strength associated with ageing, whilst reduced physical performance indicates the severity of the condition. It can happen independently of other medical conditions and can be a key feature of the frailty phenotype. Frailty is a syndrome of increased vulnerability to incomplete resolution of homeostasis, following a stressor event. Researchers have described the implications of hypothalamic pituitary dysregulation in the pathogenesis of both entities. This review summarizes the recent evidence in this area as well as other endocrine factors such as insulin resistance and vitamin D status and outlines current research priorities. We conducted searches to PubMed and Embase databases for articles, reviews and studies reporting new data on the interaction between hormones of the endocrine system and frailty and/ or sarcopenia in the last 5 years. Interventional studies, cohort studies, case-control studies and animal studies were included. Clinical trials register was also searched to identify ongoing relevant studies. Studies have given us insights into the complex relationships between factors such as anabolic hormones, glucocorticoids and vitamin D on muscle strength and performance and their involvement in ageing phenotypes. However, robust randomized controlled trials are needed to consolidate existing evidence in humans and inform clinical practice. Current evidence supports hormone replacement in patients with confirmed deficiencies, to optimize health and prevent complications. Hormone replacement has limited use for age-related conditions. Current interest is focused on muscle/bone/fat interactions and health outcomes in "sarcopenic obesity." A life-course approach to improving 'health-span' is advocated. Lifestyle factors such as nutrition and physical activity have important interactions with body composition, physical function and metabolic outcomes. Large-scale clinical trials will determine the efficacy and long-term safety of hormone supplementation in the management of sarcopenia and frailty.

Nutrition interventions implemented in hospital to lower risk of sarcopenia in older adults: A systematic review of randomised controlled trials

AIM

There is no standardised interventional approach to preventing or treating sarcopenia in older adults in hospital. The aim of this review was to systematically identify and synthesise the effects of nutritional interventions on markers of sarcopenia in hospitalised patients aged 65 years and older.

METHODS

Four databases were searched using terms for intervention, population and setting. Eligibility screening of title and abstract and then full-text papers was competed in duplicate, independently. The final included papers were assessed for quality, and outcome data extracted independently and in duplicate. Outcome data were synthesised by meta-analysis, where possible, or narratively.

RESULTS

Seven hundred and thirty-two articles were screened for eligibility yielding six studies for inclusion. All studies provided oral nutritional support that aimed to increase protein intake ranging from an additional 10 to 40 g/d, each with a unique formulation of amino acids and/or micronutrients; three studies combined nutritional intervention with an enhanced physical activity program. Five studies measured hand grip strength, the mean difference was 1.97 kg (95% CI 0.55-3.39, P = .006) greater in the intervention group (n = 166) compared with control group (n = 165). Assessment of muscle mass and activities of daily living were heterogeneous and the changes inconsistent between studies.

CONCLUSIONS

Few studies inform nutritional management of inpatients with sarcopenia or at risk of sarcopenia. High quality, large intervention trials are needed urgently to identify the optimal nutrition and physical activity intervention combinations to manage sarcopenia in older hospitalised adults. These studies need to include outcome measures of physical function and muscle quality.

Reference Values for Handgrip Strength in the Basque Country Elderly Population

Strength training is currently the most recommended primary therapeutic strategy to prevent and reverse the decline of muscle mass, strength, and functional deterioration associated with age. The aim is to provide reference values of handgrip strength (HGS) in the Basque Country population and compare the values with other populations. A total of 1869 subjects from the health-promoting programme for adults and older adults run by the Bilbao City Council were assessed using HGS with a digital dynamometer and anthropometric data measured by Tanita to obtain the mean values according to age distribution. From the 1869 subjects, 87.5% were women and 12.5% men. The HGS was higher among men than women, 32.4 ± 6.6 versus 20.1 ± 4.7 kg, respectively, p < 0.001 at all ages. Weak HGS cut-off points by age groups ranged from 31.0 to 23.8 and from 18.9 to 12.4 in men and women, respectively. The sample data were compared (d, t, and α) with those of other populations in all age groups (group > 60 years at 95% df, p < 0.05). A health-promoting programme appears to be effective in the general population in obtaining better values in the HGS test as age increases.

Prevalence and risk factors of primary sarcopenia in community-dwelling outpatient elderly: a cross-sectional study

No previous study has investigated the prevalence and risk factors for primary sarcopenia in outpatient setting. This study aims to evaluate the prevalence and factors associated with primary sarcopenia in outpatient elderly. Additionally, we compared the severity of sarcopenia based on the 2014 and 2019 Asian Working Group for Sarcopenia (AWGS) criteria. This cross-sectional study was performed in 330 subjects aged over 60 years in an outpatient setting. The muscle strength, muscle performance and muscle mass were assessed using the handheld dynamometer, 6-m gait speed, and bioelectrical impedance analysis, respectively. The prevalence of sarcopenia was 10% as per the 2014 and 2019 AWGS criteria. The development of sarcopenia was positively correlated with the age with an odds ratio (OR) of 6.87 [95% confidence interval (CI) 1.63-28.88] in the middle-old group (70-79 years), and 13.71 (95%CI 3.66-51.41; p = 0.009) in the very old group (≥ 80 years). Prefrailty and low physical activity were significantly associated with sarcopenia with an OR of 4.75 (95%CI 1.90-11.89) in prefrailty, 15.35 (95%CI 1.69-139.47) in the middle activity group, and 17.99 (95%CI 1.95-165.73) in the lowest activity group. In conclusion, primary sarcopenia was found in one-tenth of outpatient elderly. Age, prefrailty, and low activity were independent factors associated with sarcopenia.

Instrumented Analysis of the Sit-to-Stand Movement for Geriatric Screening: A Systematic Review

The Sit-to-Stand (STS) is a widely used test of physical function to screen older people at risk of falls and frailty and is also one of the most important components of standard screening for sarcopenia. There have been many recent studies in which instrumented versions of the STS (iSTS) have been developed to provide additional parameters that could improve the accuracy of the STS test. This systematic review aimed to identify whether an iSTS is a viable alternative to a standard STS to identify older people at risk of falling, frailty, and sarcopenia. A total of 856 articles were found using the search strategy developed, with 12 articles retained in the review after screening based on the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Six studies evaluated the iSTS in fallers, five studies in frailty and only one study in both fallers and frailty. The results showed that power and velocity parameters extracted from an iSTS have the potential to improve the accuracy of screening when compared to a standard STS. Future work should focus on standardizing the segmentation of the STS into phases to enable comparison between studies and to develop devices integrated into the chair used for the test to improve usability.

Sarcopenia in Type 2 Diabetes Mellitus: A Cross-Sectional Observational Study

BACKGROUND

The aim of this study was to compare the prevalence of low muscle mass and sarcopenia in patients with type 2 diabetes mellitus (T2DM) versus paired controls (control group, CG) and the association between sarcopenia and chronic diabetes complications.

METHODS

Men and women ≥50 years with T2DM (T2DM group, T2DMG) were recruited during routine outpatient visits. Total body densitometry and handgrip strength (HGS) were evaluated in the T2DMG and CG, while the T2DMG was also evaluated for the physical performance using the gait speed (GS) test. Sarcopenia was diagnosed according to the criteria of the Foundation for the National Institutes of Health Sarcopenia Project (FNIH).

RESULTS

The study included 177 individuals in the T2DMG and 146 in the CG. The mean HGS value was lower in the T2DMG (24.4 ± 10.3 kg) compared with the CG (30.9 ± 9.15 kg), p < 0.001, with low HGS in 46 (25.9%) and 10 (9%) in the T2DMG and CG, respectively (p < 0.001). The prevalence of sarcopenia defined according to the FNIH criteria was higher in the T2DMG 23 (12.9%) compared with the CG 8 (5.4%), p < 0.03. The presence of albuminuria increased the odds of sarcopenia (odds ratio (OR) 2.84, 95% confidence interval (CI) 1.07-7.68, p=0.04) and osteoporosis (OR 3.38, 95% CI 1.12-9.89, p=0.03), even in patients with mild to moderate nephropathy. The body composition analysis showed increased odds of sarcopenia with increased percentage of total fat (%TF) in women (OR 1.18, 95% CI, 1.03-1.43, p=0.03) and men (OR 1.31, 95% CI, 1.10-1.75, p=0.01).

CONCLUSION

Patients with T2DM presenting with albuminuria, osteoporosis, and increased %TF were more likely to have sarcopenia. This finding emphasizes the need for patients with T2DM to be evaluated for sarcopenia to allow for early implementation of measures to prevent or treat this disorder.

Diagnostic and Therapeutic Challenges in the Management of Intermediate and Frail Elderly Multiple Myeloma Patients

Multiple myeloma (MM) mostly affects elderly patients, which represent a highly heterogeneous population. Indeed, comorbidities, frailty status and functional reserve may vary considerably among patients with similar chronological age. For this reason, the choice of treatment goals and intensity is particularly challenging in elderly patients, and it requires a multidimensional evaluation of the patients and the disease. In recent years, different tools to detect patient frailty have been developed, and the International Myeloma Working Group frailty score currently represents the gold standard. It identifies intermediate-fit and frail patients requiring gentler treatment approaches compared to fit patients, aiming to preserve quality of life and prevent toxicities. This subset of patients is underrepresented in clinical trials, and studies exploring frailty-adapted approaches are scarce, making the choice of therapy extremely challenging. Treatment options for intermediate-fit and frail patients might include dose-adapted combinations, doublets, and less toxic combinations based on novel agents. This review analyzes the available tools for the assessment of frailty and possible strategies to improve the discriminative power of the scores and expand their use in real-life and clinical trial settings. Moreover, it addresses the main therapeutic challenges in the management of intermediate-fit and frail MM patients at diagnosis and at relapse.

Cachexia, muscle wasting, and frailty in cardiovascular disease

The last several years have seen increasing interest in understanding cachexia, muscle wasting, and physical frailty across the broad spectrum of patients with cardiovascular illnesses. This interest originally started in the field of heart failure, but has recently been extended to other areas such as atrial fibrillation, coronary artery disease, peripheral artery disease as well as to patients after cardiac surgery or transcatheter aortic valve implantation. Tissue wasting and frailty are prevalent among many of the affected patients. The ageing process itself and concomitant cardiovascular illness decrease lean mass while fat mass is relatively preserved, making elderly patients particularly prone to develop wasting syndromes and frailty. The aim of this review is to provide an overview of the available knowledge of body wasting and physical frailty in patients with cardiovascular illness, particularly focussing on patients with heart failure in whom most of the available data have been gathered. In addition, mechanisms of wasting and possible therapeutic targets are discussed.

Prevalence of sarcopenia in community-dwelling older adults using the updated EWGSOP2 definition according to kidney function and albuminuria : The Screening for CKD among Older People across Europe (SCOPE) study

Background

Loss of muscle mass and function may be more pronounced in older adults with chronic kidney disease (CKD) and with albuminuria. Thus, we investigated the prevalence of sarcopenia among community-dwelling older adults according to kidney function and grade of albuminuria. We also explored differences in the prevalence of sarcopenia according to three different equations for the estimation of glomerular filtration rate (eGFR).

Methods

A cross-sectional analysis of 1420 community-dwelling older adults (≥75 years old) included in the SCOPE study, a multicenter prospective cohort study, was conducted. Comprehensive geriatric assessment including short physical performance battery (SPPB), handgrip strength test and bioelectrical impedance analysis (BIA) was performed. Sarcopenia was defined using the updated criteria of the European Working Group on Sarcopenia in Older People (EWGSOP2). eGFR was calculated using Berlin Initiative Study (BIS), Chronic Kidney Disease Epidemiological Collaboration (CKD-EPI) and Full Age Spectrum (FAS) equations, and urinary albumin-to-creatinine ratio (ACR) was collected to categorize CKD according to Kidney Disease Improving Global Outcomes guidelines.

Results

Median age was 79.5 years (77.0–83.0), 804 (56.6%) were women. Using EWGSOP2 definition, 150 (10.6%) participants met diagnostic criteria for sarcopenia. Moreover, 85 (6%) participants had severe sarcopenia. Sarcopenia was more prevalent in participants with more advanced stages of CKD according to BIS eq. (9.6% in stages 1 and 2 and 13.9% in stages 3a, 3b and 4, p = 0.042), and also according to CKD-EPI (9.8% vs. 14.2%, p = 0.042) and FAS although not reaching statistical signification (9.8% vs. 12.7%, p = 0.119). Thus, differences in prevalence are observed among CKD categories as estimated by different equations. Prevalence of sarcopenia was also higher with increasing albuminuria categories: 9.3% in normoalbuminuric, 13.2% in microalbuminuric and 16.8% in macroalbuminuric participants, (p = 0.019).

Conclusions

Sarcopenia is common among community-dwelling older adults, especially among those with more advanced CKD categories, with prevalence estimates differing slightly depending on the equation used for the estimation of eGFR; as well as among those with higher albuminuria categories.

A subset of microRNAs in the Dlk1-Dio3 cluster regulates age-associated muscle atrophy by targeting Atrogin-1

BACKGROUND

The microRNAs (miRNAs) down-regulated in aged mouse skeletal muscle were mainly clustered within the delta-like homologue 1 and the type III iodothyronine deiodinase (Dlk1-Dio3) genomic region. Although clustered miRNAs are coexpressed and regulate multiple targets in a specific signalling pathway, the function of miRNAs in the Dlk1-Dio3 cluster in muscle aging is largely unknown. We aimed to ascertain whether these miRNAs play a common role to regulate age-related muscle atrophy.

METHODS

To examine anti-atrophic effect of miRNAs, we individually transfected 42 miRNA mimics in fully differentiated myotubes and analysed their diameters. The luciferase reporter assay using target 3' untranslated region (UTR) and RNA pull-down assay were employed to ascertain the target predicted by the TargetScan algorithm. To investigate the therapeutic potential of the miRNAs in vivo, we generated adeno-associated virus (AAV) serotype 9 expressing green fluorescent protein (GFP) (AAV9-GFP) bearing miR-376c-3p and infected it into the tibialis anterior muscle of old mice. We performed morphometric analysis and measured ex vivo isometric force using a force transducer. Human gluteus maximus muscle tissues (ages ranging from 25 to 80 years) were used to investigate expression levels of the conserved miRNAs in the Dlk1-Dio3 cluster.

RESULTS

We found that the majority of miRNAs (33 out of 42 tested) in the cluster induced anti-atrophic phenotypes in fully differentiated myotubes with increasing their diameters. Eighteen of these miRNAs, eight of which are conserved in humans, harboured predicted binding sites in the 3' UTR of muscle atrophy gene-1 (Atrogin-1) encoding a muscle-specific E3 ligase. Direct interactions were identified between these miRNAs and the 3' UTR of Atrogin-1, leading to repression of Atrogin-1 and thereby induction of eIF3f protein content, in both human and mouse skeletal muscle cells. Intramuscular delivery of AAV9 expressing miR-376c-3p, one of the most effective miRNAs in myotube thickening, dramatically ameliorated skeletal muscle atrophy and improved muscle function, including isometric force, twitch force, and fatigue resistance in old mice. Consistent with our findings in mice, the expression of miRNAs in the cluster was significantly down-regulated in human muscle from individuals > 50 years old.

CONCLUSIONS

Our study suggests that genetic intervention using a muscle-directed miRNA delivery system has therapeutic efficacy in preventing Atrogin-1-mediated muscle atrophy in sarcopenia.

Feasibility of computed tomography-based assessment of skeletal muscle mass in hemodialysis patients

BACKGROUND

Sarcopenia is a major health issue especially in patients on maintenance hemodialysis. Low skeletal muscle mass is included in the diagnostic criteria for sarcopenia. The skeletal muscle mass is usually evaluated by modalities such as bioimpedance analysis (BIA) or dual-energy X-ray absorptiometry, however the assessment of skeletal muscle mass using computed tomography (CT) images has not been established. The purpose of the study was to investigate the feasibility of the assessment of skeletal muscle mass using CT images in hemodialysis patients.

METHODS

Skeletal muscle mass index (SMI) was measured by BIA and psoas muscle index (PMI) was measured by cross-sectional CT images in 131 patients. The relationship between SMI and PMI and the diagnostic ability of PMI for low muscle mass were evaluated. Furthermore, the patients were followed up and long-term survival in patients with low and high PMI were compared.

RESULTS

PMI measured at the L3 vertebral level was strongly correlated with SMI (r = 0.597, p < 0.001). Age, sex, and SMI were the influencing factors for PMI. Patients with low PMI showed higher incidence rates of mortality during the follow up.

CONCLUSIONS

PMI assessed by CT image can be an alternative to BIA in patients on hemodialysis.

A Critical Appraisal of the Definition of Sarcopenia in Patients with Non-Alcoholic Fatty Liver Disease: Pitfall of Adjusted Muscle Mass by Body Weight

Traditionally, sarcopenia has defined as amount of absolute muscle mass adjusted by height in the elderly people. However, relative muscle mass adjusted by weight has been used extensively in most non-alcoholic fatty liver disease (NAFLD) studies. Here, we attempted to investigate the pitfall of adjusted muscle mass by weight to evaluate association between sarcopenia and NAFLD. Adult subjects (n = 1343) who underwent a health check-up were finally included for analysis. The weight-adjusted skeletal muscle mass index (wSMI) and height-adjusted SMI (hSMI) calculated by dividing the total appendicular skeletal muscle (ASM) by weight or the square of height, respectively. Prevalence of sarcopenia defined by wSMI in the NAFLD group was significantly higher than in the control group (1.3% vs. 8.8%, p < 0.001). However, there was no difference in the prevalence of sarcopenia defined by hSMI between the control and NAFLD groups (2.0% vs. 0.8%, p = 0.055). Since body weight was the most potent independent risk factor for NAFLD in multivariable logistic regression analysis, abnormal rates (<-1 SD) of almost all parameters increased in the NAFLD population, after weight adjustment. However, abnormal rates of non-metabolic parameter did not increase in NAFLD, after height adjustment. Only metabolic parameters showed relationship with NAFLD, after height adjustment. As NAFLD is highly associated with body weight, careful attention should be given in the case of studying the relationship of NAFLD with sarcopenia adjusted by body weight.

DNA methylation across the genome in aged human skeletal muscle tissue and muscle-derived cells: the role of HOX genes and physical activity

Skeletal muscle tissue demonstrates global hypermethylation with age. However, methylome changes across the time-course of differentiation in aged human muscle derived cells, and larger coverage arrays in aged muscle tissue have not been undertaken. Using 850K DNA methylation arrays we compared the methylomes of young (27 ± 4.4 years) and aged (83 ± 4 years) human skeletal muscle and that of young/aged heterogenous muscle-derived human primary cells (HDMCs) over several time points of differentiation (0, 72 h, 7, 10 days). Aged muscle tissue was hypermethylated compared with young tissue, enriched for; pathways-in-cancer (including; focal adhesion, MAPK signaling, PI3K-Akt-mTOR signaling, p53 signaling, Jak-STAT signaling, TGF-beta and notch signaling), rap1-signaling, axon-guidance and hippo-signalling. Aged cells also demonstrated a hypermethylated profile in pathways; axon-guidance, adherens-junction and calcium-signaling, particularly at later timepoints of myotube formation, corresponding with reduced morphological differentiation and reductions in MyoD/Myogenin gene expression compared with young cells. While young cells showed little alterations in DNA methylation during differentiation, aged cells demonstrated extensive and significantly altered DNA methylation, particularly at 7 days of differentiation and most notably in focal adhesion and PI3K-AKT signalling pathways. While the methylomes were vastly different between muscle tissue and HDMCs, we identified a small number of CpG sites showing a hypermethylated state with age, in both muscle tissue and cells on genes KIF15, DYRK2, FHL2, MRPS33, ABCA17P. Most notably, differential methylation analysis of chromosomal regions identified three locations containing enrichment of 6–8 CpGs in the HOX family of genes altered with age. With HOXD10, HOXD9, HOXD8, HOXA3, HOXC9, HOXB1, HOXB3, HOXC-AS2 and HOXC10 all hypermethylated in aged tissue. In aged cells the same HOX genes (and additionally HOXC-AS3) displayed the most variable methylation at 7 days of differentiation versus young cells, with HOXD8, HOXC9, HOXB1 and HOXC-AS3 hypermethylated and HOXC10 and HOXC-AS2 hypomethylated. We also determined that there was an inverse relationship between DNA methylation and gene expression for HOXB1, HOXA3 and HOXC-AS3. Finally, increased physical activity in young adults was associated with oppositely regulating HOXB1 and HOXA3 methylation compared with age. Overall, we demonstrate that a considerable number of HOX genes are differentially epigenetically regulated in aged human skeletal muscle and HDMCs and increased physical activity may help prevent age-related epigenetic changes in these HOX genes.

Prevalence of sarcopenia and its associated factors in patients attending geriatric clinics in Vietnam: a cross-sectional study

OBJECTIVES

This study aims to investigate the prevalence of sarcopenia and its associated factors in patients attending geriatric clinics in Vietnam.

DESIGN AND SETTING

A cross-sectional study was conducted in consecutive patients aged ≥60 visiting outpatient clinics of the National Geriatric Hospital in Hanoi, Vietnam, from January 2018 to October 2018. Handgrip strength was measured with a hand dynamometer. Whole-body dual-energy X-ray absorptiometry was applied to measure the appendicular skeletal muscle mass. Sarcopenia was defined by the criteria proposed by the Asian Working Group for Sarcopenia (AWGS 2019) and by the Foundation for the National Institutes of Health (FNIH) Sarcopenia Project.

RESULTS

There were 600 participants, mean age 70.0±8.0, 60.8% female. The prevalence of sarcopenia was 54.7% according to AWGS 2019 criteria and 40.5% according to FNIH. In multivariate logistic regression, age (adjusted OR 1.08, 95% CI 1.05 to 1.11), male (adjusted OR 2.03, 95% CI 1.29 to 3.21), underweight (adjusted OR 2.32, 95% CI 1.22 to 4.41), being malnourished (adjusted OR 3.77, 95% CI 1.19 to 11.91), chronic lung diseases (adjusted OR 3.48, 95% CI 2.10 to 5.77) and lower physical activity were significantly associated with sarcopenia defined by AWGS 2019 criteria. With FNIH definition, the significantly associated factors were age (adjusted OR 1.07, 95% CI 1.04 to 1.11), male (adjusted OR 6.78, 95% CI 4.12 to 11.17), low education (adjusted OR 2.15, 95% CI 1.27 to 3.63), being malnourished (adjusted OR 3.35, 95% CI 1.28 to 8.76), chronic lung diseases (adjusted OR 2.58, 95% CI 1.56 to 4.28) and lower physical activity level.

CONCLUSION

The prevalence of sarcopenia in patients attending geriatric clinics was high. Further studies are needed to examine the impact of sarcopenia on adverse outcomes in this population.

Preserving Mobility in Older Adults with Physical Frailty and Sarcopenia: Opportunities, Challenges, and Recommendations for Physical Activity Interventions

One of the most widely conserved hallmarks of aging is a decline in functional capabilities. Mobility loss is particularly burdensome due to its association with negative health outcomes, loss of independence and disability, and the heavy impact on quality of life. Recently, a new condition, physical frailty and sarcopenia, has been proposed to define a critical stage in the disabling cascade. Physical frailty and sarcopenia are characterized by weakness, slowness, and reduced muscle mass, yet with preserved ability to move independently. One of the strategies that have shown some benefits in combatting mobility loss and its consequences for older adults is physical activity. Here, we describe the opportunities and challenges for the development of physical activity interventions in people with physical frailty and sarcopenia. The aim of this article is to review age-related physio(patho)logical changes that impact mobility in old age and to provide recommendations and procedures in accordance with the available literature.

Mobility in Older Community-Dwelling Persons: A Narrative Review

Due to the demographic changes and the increasing awareness of the role of physical function, mobility in older age is becoming an important topic. Mobility limitations have been reported as increasingly prevalent in older persons affecting about 35% of persons aged 70 and the majority of persons over 85 years. Mobility limitations have been associated with increased fall risk, hospitalization, a decreased quality of life, and even mortality. As concepts of mobility are multifactorial and complex, in this narrative review, definitions, physical factors, and their age-related changes associated with mobility will be presented. Also, areas of cognitive decline and their impact on mobility, as well as neuromuscular factors related to mobility will be addressed. Another section will relate psychological factors such as Fall-related psychological concerns and sedentary behavior to mobility. Assessment of mobility as well as effective exercise interventions are only shortly addressed. In the last part, gaps and future work on mobility in older persons are discussed.

Where Two Common Conditions of Aging Meet: Osteoarthritis and Sarcopenia

Osteoarthritis and sarcopenia are the most frequently described musculoskeletal disorders in older persons but the intertwining of these conditions and of their functional and cellular causes is complex. This narrative review aims to identify the links between osteoarthritis and sarcopenia described 1-in clinical studies, 2-in in vitro studies, and 3-the available treatment strategies for both conditions. Electronic databases were used for the literature search of all studies investigating the relationship between sarcopenia and the presence of concomitant osteoarthritis. This review identified a limited number of clinical and morphometric studies on the complex relationship between osteoarthritis and sarcopenia. Studies present a number of methodological limitations due to definition and assessment of both entities. Low lean mass is one of the main actors of this cross-talk between muscle and bone, and adipose tissue plays a major role that had been underestimated. Bone Morphogenetic Proteins and myostatin pathways are key mediators and play an important role in both muscle and bone homeostasis. Common therapeutic recommendations are still missing. There is a need for good quality prospective studies on concomitant sarcopenia and osteoarthritis, more translational research, and pharmacological and non-pharmacological therapies in order to identify common denominators for the management of sarcopenia, osteoarthritis, and their comorbidities.

Protein for Community-Dwelling Older People: Aspects That Influence the Perception of Commercially Available Protein Drinks

In an aging population, support for independent living is increasingly critical for older generations. Currently, sarcopenia is a major cause of frailty, which increases the risk of decreased mobility, falls, morbidity, and mortality and leads to dependence on third parties. Sarcopenia is preventable by consumption of adequate protein. However, many older people do not meet the recommended daily allowance of protein, thereby supporting dependence rather than independent living. Current literature indicates that a protein drink could be an appropriate product for older peoples' protein consumption. We were interested in autonomous persons whose nutritional decisions were still self-determined and thus could preventively influence their personal health. This study evaluated three commercially available protein drinks in three focus groups (n = 25) to gain insight into which aspects influence the perception of commercial protein drinks on community-dwelling older people (age, 76.8 ± 4.9). Findings from the focus groups revealed only aspects, which influenced the perception of commercial protein drinks negatively. Most importantly, the drinks did not comply with relevant aspects when buying (healthy) foods, which where naturalness, freshness, locally grown ingredients, and trust. Furthermore, the target group did not see a need for additional protein consumption. Thus, we identify important aspects to be considered for the development of a target-group-specific protein drink as well as more suitable communication to prevent distrust in order to support independent living for community-dwelling older people.

Association between ultrasound quadriceps muscle status with premorbid functional status and 60-day mortality in mechanically ventilated critically ill patient: A single-center prospective observational study

BACKGROUND & AIMS

In critically ill patients, direct measurement of skeletal muscle using bedside ultrasound (US) may identify a patient population that might benefit more from optimal nutrition practices. When US is not available, survey measures of nutrition risk and functional status that are associated with muscle status may be used to identify patients with low muscularity. This study aims to determine the association between baseline and changing ultrasound quadriceps muscle status with premorbid functional status and 60-day mortality.

METHODS

This single-center prospective observational study was conducted in a general ICU. Mechanically ventilated critically ill adult patients (age ≥18 years) without pre-existing systemic neuromuscular diseases and expected to stay for ≥96 h in the ICU were included. US measurements were performed within 48 h of ICU admission (baseline), at day 7, day 14 of ICU stay and at ICU discharge (if stay >14 days). Quadriceps muscle layer thickness (QMLT), rectus femoris cross sectional area (RFCSA), vastus intermedius pennation angle (PA) and fascicle length (FL), and rectus femoris echogenicity (mean and standard deviation [SD]) were measured. Patients' next-of-kin were interviewed by using established questionnaires for their pre-hospitalization nutritional risk (nutrition risk screening-2002) and functional status (SARC-F, clinical frailty scale [CFS], Katz activities of daily living [ADL] and Lawton Instrumental ADL).

RESULTS

Ninety patients were recruited. A total of 86, 53, 24 and 10 US measures were analyzed, which were performed at a median of 1, 7, 14 and 22 days from ICU admission, respectively. QMLT, RFCSA and PA reduced significantly over time. The overall trend of change of FL was not significant. The only independent predictor of 60-day mortality was the change of QMLT from baseline to day 7 (adjusted odds ratio 0.95 for every 1% less QMLT loss, 95% confidence interval 0.91-0.99; p = 0.02). Baseline measures of high nutrition risk (modified nutrition risk in critically ill ≥5), sarcopenia (SARC-F ≥4) and frailty (CFS ≥5) were associated with lower baseline QMLT, RFCSA and PA and higher 60-day mortality.

CONCLUSIONS

Every 1% loss of QMLT over the first week of critical illness was associated with 5% higher odds of 60-day mortality. SARC-F, CFS and mNUTRIC are associated with quadriceps muscle status and 60-day mortality and may serve as a potential simple and indirect measures of premorbid muscle status at ICU admission.

Sarcopenia in Autoimmune and Rheumatic Diseases: A Comprehensive Review

Sarcopenia refers to a decrease in skeletal muscle mass and function. Because sarcopenia affects mortality, and causes significant disability, the clinical importance of sarcopenia is emerging. At first, sarcopenia was recognized as an age-related disease but, recently, it has been reported to be prevalent also in younger patients with autoimmune diseases. Specifically, the association of sarcopenia and autoimmune diseases such as rheumatoid arthritis has been studied in detail. Although the pathogenesis of sarcopenia in autoimmune diseases has not been elucidated, chronic inflammation is believed to contribute to sarcopenia, and moreover the pathogenesis seems to be different depending on the respective underlying disease. The definition of sarcopenia differs among studies, which limits direct comparisons. Therefore, in this review, we cover various definitions of sarcopenia used in previous studies and highlight the prevalence of sarcopenia in diverse autoimmune diseases including rheumatoid arthritis, spondyloarthritis, systemic sclerosis, inflammatory bowel disease, and autoimmune diabetes. In addition, we cover the pathogenesis and treatment of sarcopenia in autoimmune and rheumatic diseases. This review provides a comprehensive understanding of sarcopenia in various autoimmune diseases and highlights the need for a consistent definition of sarcopenia.

Vitamin D Inhibits Myogenic Cell Fusion and Expression of Fusogenic Genes

Vitamin D, a fat-soluble vitamin, is an important nutrient for tissue homeostasis and is recently gaining attention for its role in sarcopenia. Although several studies have focused on the role of vitamin D in muscle homeostasis, the molecular mechanism underlying its action on skeletal muscle remains unclear. This study investigated the role of vitamin D in myogenesis and muscle fiber maintenance in an immortalized mouse myogenic cell line. A high concentration of active vitamin D, 1α,25(OH)₂D₃, decreased the expression of myogenic regulatory factors (MRFs), myf5 and myogenin in proliferating myoblasts. In addition, high concentration of vitamin D reduced myoblast-to-myoblast and myoblast-to-myotube fusion through the inhibition of Tmem8c (myomaker) and Gm7325 (myomerger), which encode muscle-specific fusion-related micropeptides. A similar inhibitory effect of vitamin D was also observed in immortalized human myogenic cells. A high concentration of vitamin D also induced hypertrophy of multinucleated myotubes by stimulating protein anabolism. The results from this study indicated that vitamin D had both positive and negative effects on muscle homeostasis, such as in muscle regeneration and myofiber maintenance. Elderly individuals face a higher risk of falling and suffering fractures; hence, administration of vitamin D for treating fractures in the elderly could actually promote fusion impairment and, consequently, severe defects in muscle regeneration. Therefore, our results suggest that vitamin D replacement therapy should be used for prevention of age-related muscle loss, rather than for treatment of sarcopenia.

Suspension training vs. traditional resistance training: effects on muscle mass, strength and functional performance in older adults

PURPOSE

We compared the effects of suspension training (ST) with traditional resistance training (TRT) on muscle mass, strength and functional performance in older adults.

METHODS

Forty-two untrained older adults were randomized in TRT, ST (both performed 3 sets of whole body exercises to muscle failure) or control group (CON). Muscle thickness (MT) of biceps brachii (MT_BB) and vastus lateralis (MT_VL), maximal dynamic strength test (1RM) for biceps curl (1RM_BC) and leg extension exercises (1RM_LE), and functional performance tests (chair stand [CS], timed up and go [TUG] and maximal gait speed [MGS]) were performed before and after 12 weeks of training.

RESULTS

MT_BB increased significantly and similarly for all training groups (TRT 23.35%; ST 21.56%). MT_VL increased significantly and similarly for all training groups (TRT 13.03%; ST 14.07%). 1RM_BC increased significantly and similarly for all training groups (TRT 16.06%; ST 14.33%). 1RM_LE increased significantly and similarly for all training groups (TRT 14.89%; ST 18.06%). MGS increased significantly and similarly for all groups (TRT 6.26%; ST 5.99%; CON 2.87%). CS decreased significantly and similarly for all training groups (TRT - 20.80%; ST - 15.73%). TUG decreased significantly and similarly for all training groups (TRT - 8.66%; ST - 9.16%).

CONCLUSION

Suspension training (ST) promotes similar muscle mass, strength and functional performance improvements compared to TRT in older adults.

The Utility of Psoas Muscle Assessment in Predicting Frailty in Patients Undergoing Transcatheter Aortic Valve Replacement

Background

The rise in an ageing population has resulted in an increase in the prevalence of aortic stenosis. With the advent and rapid expansion in the use of transcatheter aortic valve replacements (TAVRs), patients with severe aortic stenosis, traditionally thought too high risk for surgical intervention, are now being treated with generally favourable results. Frailty is an important factor in determining outcome after a TAVR, and an assessment of frailty is fundamental in the identification of appropriate patients to treat.

Objective

The objective of the study was to identify if the psoas muscle area is associated with frailty in TAVR patients and outcome after intervention.

Method

In this prospective study, we measured outcomes of 62 patients who underwent TAVR procedures against the psoas muscle area and the Reported Edmonton Frail Scale (REFS). Our aim was to assess if psoas muscle assessment can be used as a simple method to predict frailty in our population group.

Results

A total of 60 patients met the study criteria. Mean psoas-lumbar vertebral index was 0.61, with a lower value in the frail group. There was not a statistically significant correlation between the psoas measures, REFS score (indicative of frailty), and mortality. However, there was a statistically significant relationship between the psoas size and REFS score (p=0.043).

Conclusion

Psoas assessment can be useful in providing additional information when planning for patients to undergo a TAVR and can be used as a screening tool to help identify frail patients within this high-risk group.

Prognostic significance of low pectoralis muscle mass on preoperative chest computed tomography in localized non-small cell lung cancer after curative-intent surgery

OBJECTIVES

The impact of sarcopenia on the outcome in patients following resection of non-small cell lung cancer is yet to be fully determined. This study aimed to evaluate the clinical utility of a computed tomography-based pectoralis muscle assessment, which reflects sarcopenia, to predict the risk of postoperative outcomes.

MATERIALS AND METHODS

This retrospective study included 347 consecutive patients undergoing curative-intent resection of non-small cell lung cancer from 2009 to 2013. The pectoralis muscle index (pectoralis muscle area/body mass index) was assessed at the level of the fourth thoracic vertebra on chest axial images. The primary outcomes were compared between the lowest gender-specific quintile (sarcopenia) and the other quintiles according to the index. The prognostic significance of low pectoralis muscle index was calculated by the Cox proportional hazards regression model. A propensity score matching analysis was performed to adjust the differences in clinical characteristics.

RESULTS

Sixty-nine patients were identified with sarcopenia according to the lowest gender-specific quintile of pectoralis muscle index. Patients with sarcopenia exhibited worse 5-year overall survival rate compared with patients without sarcopenia (64.2 % vs. 86.7 %, P < 0.001). Even in stage I non-small cell lung cancer, the rate of 5-year overall survival in the sarcopenia group was lower than that in the non-sarcopenia group (74.2 % vs. 92.4 %, P = 0.001). Multivariate analysis revealed that low pectoralis muscle index was independently associated with adverse overall survival (hazard ratio: 2.09, 95 % confidence interval: 1.20-3.62, P = 0.009). After propensity score matching, the prognostic impact of sarcopenia based on low pectoralis muscle index was also robust for overall survival (hazard ratio: 3.23, 95 % confidence interval: 1.38-7.60, P = 0.007).

CONCLUSIONS

Low pectoralis muscle index was significantly associated with poor long-term outcomes in patients with localized non-small cell lung cancer after curative surgery. This may help assist preoperative risk stratification and longitudinal management after surgery.

Risk Factors for Low Muscle Mass in a Population-based Prospective Cohort of Brazilian Community-dwelling Older Women: The São Paulo Ageing & Health (SPAH) Study

INTRODUCTION

Sarcopenia is characterized by progressive loss of skeletal muscle mass, which results in decreased muscle strength, functional impairment, and increased risk of death. Few studies have performed a concomitant evaluation of clinical, laboratory, and body composition variables to accurately determine the contribution of each parameter to low muscle mass (LMM) in older subjects. This study aimed to identify risk factors (clinical, laboratory parameters, BMD, and body composition by DXA including visceral fat) for LMM in a prospective cohort of older Brazilian women.

METHODS

A total of 408 women aged ≥65 yr from the São Paulo Ageing & Health study were evaluated with clinical data, laboratory bone tests, BMD, and body composition by DXA using Hologic QDR 4500A equipment. Risk factors were measured at baseline (2005-2007). After a follow-up of 4.3 ± 0.8 yr, subjects were classified according to the LMM definition of the Foundation for the National Institutes of Health criteria. LMM was defined when appendicular lean mass divided by body mass index was less than 0.512. Multivariate logistic regression models were used to identify independent risk factors for LMM.

RESULTS

At the end of follow-up, 116 women (28.4%) had LMM. Age averages were 73.3 ± 4.9 yr in the LMM group and 72.5 ± 4.5 yr in the normal group (p = 0.11). Mean BMI was 30.6 ± 5.2 kg/m² in the LMM group and 28.1 ± 4.7 kg/m² in the normal group (p < 0.001). In multivariate analyses, predictors of LMM were: falls (OR = 1.14, p = 0.016), TSH levels (OR = 1.08, p = 0.018, per 1 μUI/L-increase), serum creatinine levels (OR = 11.11, p < 0.001, per 1 mg/dL-decrease), and visceral adipose tissue (VAT) mass (OR = 1.17, p < 0.001, per 100 g increase).

CONCLUSIONS

Falls, high TSH, low creatinine, and high VAT were risk factors for LMM in older women. More attention should be paid to these factors, since they are potentially reversible with adequate intervention.

Emerging molecular mediators and targets for age-related skeletal muscle atrophy

The age-associated decline in muscle mass has become synonymous with physical frailty among the elderly due to its major contribution in reduced muscle function. Alterations in protein and redox homeostasis along with chronic inflammation, denervation, and hormonal dysregulation are all hallmarks of muscle wasting and lead to clinical sarcopenia in older adults. Reduction in skeletal muscle mass has been observed and reported in the scientific literature for nearly 2 centuries; however, identification and careful examination of molecular mediators of age-related muscle atrophy have only been possible for roughly 3 decades. Here we review molecular targets of recent interest in age-related muscle atrophy and briefly discuss emerging small molecule therapeutic treatments for muscle wasting in sarcopenic susceptible populations.

Identification of Sarcopenia Components That Discriminate Slow Walking Speed: A Pooled Data Analysis

BACKGROUND

The Sarcopenia Definitions and Outcomes Consortium (SDOC) sought to identify cut points for muscle strength and body composition measures derived from dual-energy x-ray absorptiometry (DXA) that discriminate older adults with slow walking speed. This article presents the core analyses used to guide the SDOC position statements.

DESIGN

Cross-sectional data analyses of pooled data.

SETTING

University-based research assessment centers.

PARTICIPANTS

Community-dwelling men (n = 13,652) and women: (n = 5,115) with information on lean mass by DXA, grip strength (GR), and walking speed.

MEASUREMENTS

Thirty-five candidate sarcopenia variables were entered into sex-stratified classification and regression tree (CART) models to agnostically choose variables and cut points that discriminate slow walkers (<0.80 m/s). Models with alternative walking speed outcomes were also evaluated (<0.60 and <1.0 m/s and walking speed treated continuously).

RESULTS

CART models identified GR/body mass index (GRBMI) and GR/total body fat (GRTBF) as the primary discriminating variables for slowness in men and women, respectively. Men with GRBMI of 1.05 kg/kg/m2 or less were approximately four times more likely to be slow walkers than those with GRBMI of greater than 1.05 kg/kg/m2 . Women with GRTBF of less than 0.65 kg/kg were twice as likely to be slow walkers than women with GRTBF of 0.65 kg/kg or greater. Models with alternative walking speed outcomes selected only functions of GR as primary discriminators of slowness in both men and women. DXA-derived lean mass measures did not consistently discriminate slow walkers.

CONCLUSION

GR with and without adjustments for body size and composition consistently discriminated older adults with slowness. CART models did not select DXA-based lean mass as a primary discriminator of slowness. These results were presented to an SDOC Consensus Panel, who used them and other information to develop the SDOC Position Statements. J Am Geriatr Soc 68:1419-1428, 2020.

Muscle strength and gait speed rather than lean mass are better indicators for poor cognitive function in older men

We aimed to examine muscle strength, function and mass in relation to cognition in older men. This cross-sectional data-set included 292 men aged ≥60 yr. Handgrip strength (kg) was measured by dynamometry, gait speed by 4-metre walk (m/s) and appendicular lean mass (kg) by dual-energy x-ray absorptiometry. Cognition was assessed across four domains: psychomotor function, attention, visual learning and working memory. Composite scores for overall cognition were calculated. Bivariate analyses indicated that handgrip strength and gait speed were positively associated with cognitive function. After accounting for confounders, positive associations between individual muscle (or physical) measures and cognitive performance were sustained for handgrip strength and psychomotor function, gait speed and psychomotor function, gait speed and attention, handgrip strength and overall cognition, and gait speed and overall cognition. In multivariable models, handgrip strength and gait speed independently predicted psychomotor function and overall cognition. No associations were detected between lean mass and cognition after adjusting for confounders. Thus, low muscle strength and slower gait speed, rather than low lean mass, were associated with poor cognition in older men.

The effect of vitamin D on sarcopenia depends on the level of physical activity in older adults

OBJECTIVE

Sarcopenia in older adults is closely related to vitamin D deficiency and reduced levels of physical activity, but little has been reported on the interaction between physical activity and the positive effects of vitamin D. The purpose of this study was to explore the interactive effect of vitamin D and physical activity on muscle mass and function through animal experiments and population surveys.

METHODS

Male 4-week-old C57BL/6J mice were fed different purified diets: a vitamin D-deficient diet (with increased calcium and phosphorus to prevent the effects of abnormal mineral levels on muscle) or a 1,25-dihydroxyvitamin D3 (1,25D)-supplemented diet. After 24 weeks on the assigned diets, the mice were immobilized. The level of skeletal muscle atrophy in the mice was determined by grip strength, gastrocnemius (GA) muscle mass and muscle fiber cross-sectional area (CSA); additionally, the protein expression levels of FOXO3a and the E3 ubiquitin ligases MuRF1 and MAFbx were detected. A cross-sectional study included data from 4139 older adults (64.9% women, 67.9 ± 6.7 years) as part of a survey in Shenyang, Northeast China. The associations of serum 25(OH)D3 and physical activity with timed up and go test (TUG) performance, handgrip strength, calf circumference, and body muscle mass were assessed by a linear regression analysis that was adjusted for covariates.

RESULTS

In activity-limited mice, vitamin D deficiency accelerated the decrease in GA muscle weight, muscle fiber CSA, and grip strength and increased the protein expression of MuRF1, MAFbx, and FOXO3a (all P < 0.05). In addition, 1,25D supplementation may inhibit the grip-strength reduction induced by limited activity (P = 0.069). Serum 25(OH)D3 and physical activity were linearly related to TUG time (P < 0.001) and handgrip strength (P < 0.05) after adjustment for sex, age, body mass index (BMI), education level, smoking status, and serum calcium level. Serum 25(OH)D3 and physical activity had interactive effects on TUG (P < 0.001) and handgrip strength (P < 0.05) but not calf circumference or body muscle mass in older adults.

CONCLUSIONS

The effect of vitamin D on muscle strength and physical performance depends on physical activity level in the elderly. It is recommended that older adults strive to avoid both physical inactivity and vitamin D deficiency. Because physical inactivity and vitamin D deficiency may exacerbate muscle atrophy, the biological mechanism may involve synergistic effects of vitamin D and physical activity on the promotion of muscle protein ubiquitination and degradation.

Abnormalities of Skeletal Muscle, Adipocyte Tissue, and Lipid Metabolism in Heart Failure: Practical Therapeutic Targets

Chronic diseases, including heart failure (HF), are often accompanied with skeletal muscle abnormalities in both quality and quantity, which are the major cause of impairment of the activities of daily living and quality of life. We have shown that skeletal muscle abnormalities are a hallmark of HF, in which metabolic pathways involving phosphocreatine and fatty acids are largely affected. Not only in HF, but the dysfunction of fatty acid metabolism may also occur in many chronic diseases, such as arteriosclerosis, as well as through insufficient physical exercise. Decreased fatty acid catabolism affects adenosine triphosphate (ATP) production in mitochondria, via decreased activity of the tricarboxylic acid cycle; and may cause abnormal accumulation of adipose tissue accompanied with hyperoxidation and ectopic lipid deposition. Such impairments of lipid metabolism are in turn detrimental to skeletal muscle, which is hence a chicken-and-egg problem between skeletal muscle and HF. In this review, we first discuss skeletal muscle abnormalities in HF, including sarcopenia; particularly their association with lipid metabolism and adipose tissue. On the other hand, the precise mechanisms involved in metabolic reprogramming and dysfunction are beginning to be understood, and an imbalance of daily nutritional intake of individuals has been found to be a causative factor for the development and worsening of HF. Physical exercise has long been known to be beneficial for the prevention and even treatment of HF. Again, the molecular mechanisms by which exercise promotes skeletal muscle as well as cardiac muscle functions are being clarified by recent studies. We propose that it is now the time to develop more “natural” methods to prevent and treat HF, rather than merely relying on drugs and medical interventions. Further analysis of the basic design of and molecular mechanisms involved in the human body, particularly the inextricable association between physical exercise and the integrity and functional plasticity of skeletal and cardiac muscles is required.

Effects of the Combination of β-Hydroxy-β-Methyl Butyrate and R(+) Lipoic Acid in a Cellular Model of Sarcopenia

: Sarcopenia is a clinical problem associated with several pathological and non-pathological conditions. The aim of the present research is the evaluation of the pharmacological profile of the leucine metabolite β-hydroxy-β-methyl butyrate (HMB) associated with the natural R(+) stereoisomer of lipoic acid (R(+)LA) in a cellular model of muscle wasting. The C2C12 cell line is used as myoblasts or is differentiated in myotubes, sarcopenia is induced by dexamethasone (DEX). A Bonferroni significant difference procedure is used for a post hoc comparison. DEX toxicity (0.01-300 µM concentration range) is evaluated in myoblasts to measure cell viability and caspase 3 activation after 24 h and 48 h; cell incubation with 1 µM DEX for 48 h is chosen as optimal treatment for decreasing cell viability and increasing caspase 3 activity. R(+)LA or HMB significantly prevents DEX-induced cell mortality; the efficacy is improved when 100 µM R(+)LA is combined with 1 mM HMB. Regarding myoblasts, this combination significantly reduces DEX-evoked O2- production and protein oxidative damage. During the early phase of myotube formation, the mixture preserves the number of myogenin-positive cells, whereas it completely prevents the DEX-dependent damage in a later phase of myotube differentiation (7 days), as evaluated by cell diameter and percentage of multinucleated cells. R(+)LA in association with HMB is suggested for sarcopenia therapy.