Sarcopenia and Predictors of Skeletal Muscle Mass in Elderly Men With and Without Obesity

Sex-Specific Sarcopenia Prevalence and Risk Factors in the Korean Population: A Cross-Sectional Epidemiological Study

Background and Objective: This study aimed to identify the incidence of sarcopenia and disease risk factors in Korean adults and to provide data for sarcopenia prevention. Materials and Methods: Based on the Korea National Health and Nutrition Survey, 2008-2011, we selected 14,185 adults over the age of 20 who participated in sarcopenia diagnostic tests and health surveys. We analyzed sarcopenia risk factors using complex sample multi-logistic regression analysis. Results: The prevalence of sarcopenia in Korea was 31.3%, with 20.2% in men and 40.4% in women. In men, there was a higher risk of sarcopenia in those of older age, without a spouse, with a low body mass index (BMI), who never engage in resistance exercise, or who do mid-level intensity resistance exercises. In women, sarcopenia risk was higher in those in their 20s compared to those in their 60s, and risk factors included a low BMI, high-density lipoprotein cholesterol and waist circumference measurements, alcohol consumption, aerobic exercise, and resistance exercise. Conclusions: Interventions and lifestyle improvements will help prevent the onset of sarcopenia in elderly men and young women with risk factors such as a low BMI.

Relationship between muscle mass and muscle strength with physical performance in older adults: A systematic review

Background

Declining muscle mass is not always accompanied by declining muscle strength in older adults, challenging the notion that low muscle mass is the sole criterion for diagnosing sarcopenia.

Objective

This review aims to find out the relationships between muscle mass and muscle strength with physical performance in older adults.

Design

This article was a systematic review using Preferred Reporting Items for Systematic Reviews and Meta-Analysis guidelines.

Data Sources and Methods

We do a systematic search of observational studies that are published between 2013 and August 2023 in PubMed, ScienceDirect, Sage journal, Tripdatabase, Cochrane Library, Embase, and CINAHL. Two reviewers selected and extracted data independently and an association measure was recorded from included studies.

Results

The review analyzed 17 observational studies conducted between 2013 and September 2023. The findings suggest that while declining muscle mass is often associated with sarcopenia, it may not always correspond to declining muscle strength in older individuals. The most common method used to measure muscle mass was bioelectrical impedance analysis, while handgrip strength was the predominant measure of muscle strength. Tests such as timed up and go and gait speed were used to assess physical performance.

Conclusions

Physical performance in older adults is significantly related to muscle strength, whereas the relationship between muscle mass and physical performance is either weak or negligible. Therefore, when evaluating physical performance in older individuals, focusing on muscle strength is more important than muscle mass alone.

The Use of Practical Measures to Determine Body Composition of Older People

Background

Older adults frequently experience body composition changes-decreased lean body mass (LBM) and bone mineral content (BMC), along with increased body fat mass (FM)-which affect their health and independence. However, the need for standard complex and costly imaging modalities could delay the detection of these changes and retard treatment effectiveness. Thus, this study explored the ability of practical measures, including simple muscle strength tests and demographic data, to determine the body composition of older adults.

Methods

Participants (n = 111, with an average age of 77 years old) were cross-sectionally assessed for the outcomes of the study, including upper limb loading during a seated push-up test (ULL-SPUT), hand grip (HG) strength test and body composition.

Results

The ULL-SPUT significantly correlated with body composition (r or rs, = 0.370-0.781; P < 0.05), particularly for female participants and was higher than that found for the HG strength test (rs = 0.340-0.614; P < 0.05). The ULL-SPUT and HG strength test, along with gender and body mass index (BMI), could accurately determine the LBM and BMC of the participants up to 82%.

Conclusion

The ULL-SPUT along with gender and BMI can be used as a practical strategy to detect the LBM and BMC of older adults in various settings. Such a strategy would facilitate timely managements (i.e. standard confirmation or appropriate interventions) in various settings.

Myostatin and its Regulation: A Comprehensive Review of Myostatin Inhibiting Strategies

Myostatin (MSTN) is a well-reported negative regulator of muscle growth and a member of the transforming growth factor (TGF) family. MSTN has important functions in skeletal muscle (SM), and its crucial involvement in several disorders has made it an important therapeutic target. Several strategies based on the use of natural compounds to inhibitory peptides are being used to inhibit the activity of MSTN. This review delivers an overview of the current state of knowledge about SM and myogenesis with particular emphasis on the structural characteristics and regulatory functions of MSTN during myogenesis and its involvements in various muscle related disorders. In addition, we review the diverse approaches used to inhibit the activity of MSTN, especially in silico approaches to the screening of natural compounds and the design of novel short peptides derived from proteins that typically interact with MSTN.

Hand-grip strength as a screening tool for sarcopenia in males with decompensated cirrhosis

BACKGROUND

Skeletal muscle index (SMI), the gold standard for sarcopenia, cannot measure muscle strength and requires specialized software and training. Hand-grip strength (HGS) measurement is cheap, requires minimal training and directly reflects muscle strength. We assessed the performance of HGS as a screening tool for sarcopenia in male patients with decompensated cirrhosis (DC).

METHODS

Consecutive male DC patients (n=155) were enrolled. Baseline liver functions, etiologic work-up and anthropometric measurements were done. SMI was determined from computed tomography (CT) images at L3 level using ImageJ software. Sarcopenia was diagnosed using SMI cut-off <42 cm²/m² as suggested by the Indian National Association for Study of the Liver. HGS was assessed using a hand-grip dynamometer. Diagnostic performance of HGS for discriminating sarcopenia was described using receiver operating characteristic (ROC) analysis. Diagnostic performance of different HGS cut-offs was assessed. Findings were internally validated using bootstrapping.

RESULTS

Mean HGS and SMI were 25.73 ± 5.94 kg and 47.72 ± 8.71 cm²/m², respectively. HGS showed modest correlation with SMI (tau: 0.31, p <0.001). Sarcopenia was seen in 41 (26.5%) patients. Age and HGS were independent predictors of sarcopenia on multivariate analysis. Area under the ROC curve (AUROC) of HGS for detecting sarcopenia was 0.73 (p<0.001). Optimal cut-off for using HGS as a screening tool was ≤31 kg (sensitivity: 37/41 [90.2%]; specificity: 29/114 [25.4%]; positive predictive value [PPV] : 37/122 [30.3%]; and negative predictive value [NPV]: 29/33 [87.9%]).

CONCLUSION

Prevalence of sarcopenia in Indian male patients with DC is 26.5%. HGS is an independent predictor of sarcopenia and can be used as a screening tool to stratify the need for confirmatory CT-based assessment of sarcopenia.

Sex differences in association between body composition and frailty or physical performance in community-dwelling older adults

Frailty is a common geriatric condition due to aging, defined as a decrease in the functional reserve to maintain the homeostasis. As part of the aging process, body composition changes occur. This study investigated the relationship between body composition and frailty in a community-dwelling elderly Korean population.This cross-sectional cohort study analyzed data of 2,385 elderly participants (aged 70-84 years, 1131 males and 1254 females) of the Korean Frailty and Aging Cohort Study from 2016 to 2017. Body composition, including total and trunk fat masses and fat-free mass, were measured with dual-energy X-ray absorptiometry. Fat mass index (FMI), trunk fat mass index, and fat-free mass index (FFMI) represented total fat mass, trunk fat mass, and fat-free mass according to height. Based on the frailty index developed by Fried, we compared the frail and non-frail groups. Poor physical performance assessed with the short physical performance battery score of < 9 is considered frailty. To evaluate the relationship between the variables, simple and fully adjusted multivariable logistic regression analyses were performed according to sex.Among the participants, 462 (19.3%) were defined as the frail group, with a significantly high mean age of 77.9 ± 4.0 years. In the logistic regression analysis of frailty based on body mass index (BMI) categories, underweight (BMI < 18 kg/m2) participants showed a high incidence of frailty in both sexes. BMI showed an association with frailty only in males. Lower FFMI was associated with a higher incidence of frailty in both sexes, which was statistically significant in the fully adjusted models. In the female, fat-related indexes including body fat percentage, FMI, and trunk fat mass index showed a significant association with poor physical performance. In contrast, males with low FFMI only showed a significant association with poor physical performance.Frailty was closely correlated with lower FFMI in both sexes. The poor physical performance associated with frailty correlated with fat-related body composition in females and fat-free mass in males, owing to the difference in body composition between the sexes. In the assessment of frailty, body composition and sex-related differences should be analyzed.

Impact of Gait Speed on the Obesity Paradox in Older Patients With Cardiovascular Disease

PURPOSE

The purpose of this study was to determine whether gait speed affects the obesity paradox in older patients with cardiovascular disease.

METHODS

The study population consisted of 2224 patients ≥60 years old with cardiovascular disease admitted to hospital between May 1, 2006, and January 31, 2018. Body mass index (BMI) and gait speed before hospital discharge were determined, and patients were divided into two groups: slow and preserved gait speed (≤0.8 and >0.8 m/s, respectively), according to the algorithm for sarcopenia diagnosis. The slow and preserved gait speed groups were also further subdivided according to BMI: <18.5 kg/m², 18.5-24.9 kg/m², and BMI ≥25.0 kg/m². The study endpoint was all-cause mortality.

RESULTS

The study population (male: 66.7%) had a mean age of 73.1 ± 7.6 years. Over a median follow-up period of 1.69 years (interquartile range 0.67-3.67 years), 283 patients died. Higher BMI was associated with favorable prognosis in the group with preserved gait speed but not in the group with slow gait speed after adjusting for other prognostic factors. Adding BMI to the clinical model significantly increased the area under the receiver operating characteristic curve in the group with preserved gait speed (0.744 vs 0.726, P = 0.028) but not in the group with slow gait speed (0.716 vs 0.716, P = 0.789).

CONCLUSIONS

Higher BMI was consistently associated with favorable prognosis in patients with cardiovascular disease and preserved gait speed but not in those with slow gait speed. These findings indicated that physical frailty influences the obesity paradox in older patients with cardiovascular disease.

Association between asymmetry in lower extremity lean mass and functional mobility in older adults living in the community: Results from the Korean Frailty and Aging Cohort Study

The asymmetry in lower extremity strength is known to be related to the functional mobility in older adults living in the community. However, little is known about the association between lower extremity lean mass asymmetry and functional mobility in this patient group. Hence, this study aimed to determine whether asymmetry in lower extremity muscle mass has a significant relationship with functional mobility in older adults living in the community.This cross-sectional study analyzed the pre-existing data from the Korean Frailty and Aging Cohort Study. A total of 435 older people (aged 70-84 years) were divided into the following groups according to their Limb Asymmetry Index (LAsI): low, intermediate, and high asymmetric groups. LAsI is calculated using lower extremity lean mass, and comparisons between groups were conducted. The participants were also further divided into better and worse mobility groups based on their physical performance test results (Timed Up and Go and Short Physical Performance Battery), and comparisons between groups were conducted. Comparisons between fallers and non-fallers were also conducted. In addition, this study investigated the factors that had a significant effect on gait speed and fall experience within the past year among older adults living in the community.The LAsI was significantly associated with gait speed in older adults living in the community. Older adults in the highest tertile of the LAsI had a slower gait speed than those in the lowest tertile of the LAsI. However, no significant difference was observed in the LAsI between the better mobility group and worse mobility group. Moreover, the LAsI was not a significant predictor of falls.Asymmetry in lower extremity lean mass was significantly associated with gait speed in older adults living in the community.

Chronic vitamin D insufficiency impairs physical performance in C57BL/6J mice

Vitamin D insufficiency (serum 25-OH vitamin D < 30 ng/ml) affects 70-80% of the general population, yet the long-term impacts on physical performance and the progression of sarcopenia are poorly understood. We therefore followed 6-month-old male C57BL/6J mice (n=6) consuming either sufficient (STD, 1000 IU) or insufficient (LOW, 125 IU) vitamin D3/kg chow for 12 months (equivalent to 20-30 human years). LOW supplemented mice exhibited a rapid decline of serum 25-OH vitamin D levels by two weeks that remained between 11-15 ng/mL for all time points thereafter. After 12 months LOW mice displayed worse grip endurance (34.6 ± 14.1 versus 147.5 ± 50.6 seconds, p=0.001), uphill sprint speed (16.0 ± 1.0 versus 21.8 ± 2.4 meters/min, p=0.0007), and stride length (4.4 ± 0.3 versus 5.1 ± 0.3, p=0.002). LOW mice also showed less lean body mass after 8 months (57.5% ± 5.1% versus 64.5% ± 4.0%, p=0.023), but not after 12 months of supplementation, as well as greater protein expression of atrophy pathway gene atrogin‑1. Additionally, microRNA sequencing revealed differential expression of mIR‑26a in muscle tissue of LOW mice. These data suggest chronic vitamin D insufficiency may be an important factor contributing to functional decline and sarcopenia.

Frailty syndrome in the elderly in elderly with chronic diseases in Primary Care

OBJECTIVE

To evaluate the frailty syndrome in the elderly nursing diagnosis in elderly with chronic diseases of a health district of the Federal District.

METHOD

A quantitative, descriptive, cross-sectional study was conducted with elderly patients served at the Basic Health Units, who presented arterial hypertension and/or diabetes mellitus. The following were used: a sociodemographic questionnaire, the Mini-Mental State Examination, anthropometric data, evaluation of sarcopenia (measured by body composition), muscle strength and functional capacity, and the identification of NANDA-I nursing diagnosis. A statistical software was used for data analysis.

RESULTS

Participation of 78 elderly people, of which 93.6% of had Impaired memory, 93.6% had Impaired physical mobility, 82.1% had Fatigue, 76.9% had Impaired ambulation, 53.8% had Dressing self-care deficit, 43.6% had Activity Intolerance, 35.9% had Social Isolation, 30.8% had Hopelessness, 29.5% had Feeding self-care deficit, 29.5% had Bathing self-care deficit, 12.8% had Toileting self-care deficit, and 10.3% had Decreased cardiac output.

CONCLUSION

The nursing diagnosis Frailty Syndrome in the Elderly allows a multidimensional view of the elderly. Since one factor can cause health problems in several health fields, nurses must intervene early, plan and implement actions in the short and long term.

Muscle quality as a complementary prognostic tool in conjunction with sarcopenia assessment in younger and older individuals

PURPOSE

This pilot study investigated differences in lean tissue mass, muscle strength, muscle quality (strength per unit of muscle mass; MQ), and functional performance in healthy younger and older individuals. The most robust predictors of appendicular lean mass (ALM) were then determined in each group.

METHODS

Fifty younger (18-45 years) and 50 older (60-80 years) participants completed tests of upper and lower body strength alongside body composition by dual-energy X-ray absorptiometry from which upper- and lower-body MQ were estimated. Available cut-points for older people were used to determine low upper-body MQ in both groups. Low lower-body MQ was determined as at least two standard deviations below the mean of the younger group. Functional performance was assessed by gait speed. Sarcopenia was identified using two established definitions.

RESULTS

Upper and lower body strength, ALM, lower-body MQ and gait speed were significantly higher in the younger group (all p < 0.002). Sarcopenia was identified in 2-4% of the older group. Low upper-body MQ was evident in 32% and 42% of the younger and older group, respectively. Low lower-body MQ was observed in 4% of younger participants, and 50% of older participants. In both groups, the most robust predictors of ALM were upper and lower body strength (young R2 = 0.74, 0.82; older R2 = 0.68, 0.72).

CONCLUSIONS

Low MQ despite low prevalence rates of sarcopenia in both groups suggests a need for age-specific MQ cut-points. Muscle quality assessments might be useful complementary prognostic tools alongside existing sarcopenia definitions.

Sarcopenia of the Psoas Muscles Is Associated With Poor Outcomes Following Lung Transplantation

BACKGROUND

Sarcopenia, a known component of frailty, defined by diminished cross-sectional area of the psoas muscles, is associated with poor outcomes after a range of surgical procedures. However, little is known of the relationship between sarcopenia of the psoas muscles (SPM) and long-term survival, decline in pulmonary function, and graft failure after lung transplantation.

METHODS

We reviewed patients who underwent primary lung transplantation at our institution from 2011 to 2014. Cross-sectional areas of the psoas muscles at the L4 vertebral level were measured using preoperative computed tomography. Gender-based cutoff values for sarcopenia were generated and validated. The primary outcomes were 1-, 2-, and 3-year all-cause mortality, forced expiratory volume in 1 second values, and graft function. Adjusted logistic regression and survival analysis was used to analyze outcomes.

RESULTS

Ninety-five patients were included in this study; 39 (41.1%) patients were considered sarcopenic. SPM was significantly associated with short-term and midterm mortality on multivariate analysis (1 year: odds ratio [OR], 8.7, p = 0.017; 2 years: OR, 12.7, p < 0.01; 3 years: OR, 13.4, p < 0.01). Survival analysis showed significantly decreased survival in sarcopenic patients at 3 years (35.9% versus 76.8%; p < 0.01). SPM is also associated with decreased forced expiratory volume in 1 second (coefficient, -17.3; p = 0.03). Adjusted Cox analysis showed an increased hazard for all-cause mortality (hazard ratio, 5.8, p < 0.01) and graft failure (hazard ratio, 14.7, p < 0.01) in sarcopenic patients.

CONCLUSIONS

This study demonstrates a significant association between SPM and death, pulmonary function, and graft failure in patients receiving a lung transplant. Determining SPM preoperatively may be a useful component of frailty assessment and a predictor of survival in this patient population.

Single Physical Performance Measures Cannot Identify Geriatric Outpatients with Sarcopenia

Background

Sarcopenia is highly prevalent in the older population and is associated with several adverse health outcomes. Equipment to measure muscle mass and muscle strength to diagnose sarcopenia is often unavailable in clinical practice due to the related expenses while an easy physical performance measure to identify individuals who could potentially have sarcopenia is lacking.

Objectives

This study aimed to assess the association between physical performance measures and definitions of sarcopenia in a clinically relevant population of geriatric outpatients.

Design, setting and participants

A cross-sectional study was conducted, consisting of 140 community-dwelling older adults that were referred to a geriatric outpatient clinic. No exclusion criteria were applied.

Measurements

Physical performance measures included balance tests (sideby- side, semi-tandem and tandem test with eyes open and -closed), four-meter walk test, timed up and go test, chair stand test, handgrip strength and two subjective questions on mobility. Direct segmental multi-frequency bioelectrical impedance analysis was used to measure muscle mass. Five commonly used definitions of sarcopenia were applied. Diagnostic accuracy was determined by sensitivity, specificity and area under the curve.

Results

Physical performance measures, i.e. side-by-side test, tandem test, chair stand test and handgrip strength, were associated with at least one definition of sarcopenia. Diagnostic accuracy of these physical performance measures was poor.

Conclusions

Single physical performance measures could not identify older individuals with sarcopenia, according to five different definitions of sarcopenia.

Is there a social gradient of sarcopenia? A meta-analysis and systematic review protocol

INTRODUCTION

Sarcopenia (or loss of muscle mass and function) is a relatively new area within the field of musculoskeletal research and medicine. Investigating whether there is a social gradient, including occupation type and income level, of sarcopenia, as observed for other diseases, will contribute significantly to the limited evidence base for this disease. This new information may inform the prevention and management of sarcopenia and widen the evidence base to support existing and future health campaigns.

METHODS AND ANALYSIS

We will conduct a systematic search of the databases PubMed, Ovid, CINAHL, Scopus and EMBASE to identify articles that investigate associations between social determinants of health and sarcopenia in adults aged 50 years and older. Eligibility of the selected studies will be determined by two independent reviewers. The methodological quality of eligible studies will be assessed according to predetermined criteria. Established statistical methods to identify and control for heterogeneity will be used, and where appropriate, we will conduct a meta-analysis. In the event that heterogeneity prevents numerical synthesis, a best evidence analysis will be employed. This systematic review protocol adheres to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses Protocols reporting guidelines and will be registered with the International Prospective Register of Systematic Reviews (PROSPERO).

ETHICS AND DISSEMINATION

This systematic review will use published data, thus ethical permissions will not be required. In addition to peer-reviewed publication, our results will be presented at (inter)national conferences relevant to the field of sarcopenia, ageing and/or musculoskeletal health and disseminated both electronically and in print.

PROSPERO REGISTRATION NUMBER

CRD42017072253.

Sarcopenia: prevalence and prognostic implications in elderly patients with cardiovascular disease

BackgroundSarcopenia has recently been given an ICD-10 code. However, there have been no systematic investigations regarding the prevalence or prognostic value of sarcopenia in cardiovascular disease (CVD) according to the international consensus definition. The present study was performed to investigate the prevalence and prognostic value of sarcopenia in elderly patients with CVD.MethodsThe study population consisted of 1603 admitted patients aged ≥ 65 years (74.4 ± 6.2 years, 1049 men) with CVD. Sarcopenia was defined according to the recommended diagnostic algorithm of the Asia Working Group for Sarcopenia. The endpoint for the study was all-cause mortality.ResultsThe overall sarcopenia prevalence rate was 29.7% (19.6% in men and 48.7% in women). The prevalence rates of sarcopenia across major diagnostic categories were as follows: acute coronary syndrome, 17.8%; post-cardiac surgery, 31.8%; and heart failure, 35.2%. During the 2.3 ± 2.1-year follow-up period, 175 deaths occurred. Patients with sarcopenia showed higher risk of all-cause mortality compared with non-sarcopenic patients (adjusted hazard ratio: 1.46; 95% confidence interval: 1.03 – 2.08; P = 0.036).ConclusionsSarcopenia is highly prevalent among elderly patients with CVD and is associated with increased mortality risk.