Low Muscle Mass Group Research Articles

Sex-Specific Association of Low Muscle Mass with Depression Status in Asymptomatic Adults: A Population-Based Study

Background: The objective of this study was to examine the correlation between low muscle mass (LMM) and depression, with a specific focus on identifying the sex-specific relationship between LMM and depression in a large sample. Methods: This population-based cross-sectional study involved 292,922 community-dwelling adults from 2012 to 2019. Measurements were taken using the Center for Epidemiological Studies Depression (CESD) scale and body composition analyses. Depression was defined as a CESD score ≥ 16, and severe depression as a CESD score ≥ 22. LMM was defined as an appendicular muscle mass/height2 below 7.0 kg/m2 in men and below 5.4 kg/m2 in women. Sex-based multivariable logistic regression analyzed the LMM–depression association, adjusting for confounders, with depression status and severe depression status as dependent variables. Results: Both men and women in the LMM group had an increased odds of depression (men, adjusted odds ratio = 1.13 [95% confidence interval = 1.03–1.12]; women, 1.07 [1.03–1.23]) and severe depression (men, 1.20 [1.05–1.36]; women, 1.10 [1.04–1.15]) compared to those in the control group. Men showed a stronger association between LMM and the presence of depression (p for interaction = 0.025) and the presence of severe depression (p for interaction = 0.025) compared to women. Conclusions: Decreased muscle mass was independently associated with increased chances of depression and severe depression in both sexes, with a significantly stronger association in men compared to women. This highlights the potential significance of LMM as a predictor of depression, particularly in men.

The coexistence of low muscle mass and obesity evaluated by dual energy X-ray absorptiometry, rather than low muscle mass or obesity alone, is associated with macrovascular but not microvascular complications in patients with type 2 diabetes mellitus.

The prevalence of the coexistence of low muscle mass and obesity is increasing, particularly with a rising trend observed in patients diagnosed with type 2 diabetes mellitus (T2DM). However, the association between the coexistence of low muscle mass and obesity and diabetic complications remains unclear. This study aimed to investigate these associations in patients with T2D. A retrospective study was conducted, including 2387 hospitalized patients with T2DM. Data on demographic characteristics, biochemical parameters, diabetic complications and body composition was from electronic health records. The participants were categorized as control, low muscle mass, obesity and the coexistence of the low muscle mass and obesity groups according to the body compositions evaluated by dual-energy X-ray absorptiometry. Multiple logistic regression models were applied to assess the associations between the pattern of body composition and complications of diabetes. After adjustment for potential confounders, compared with patients in the control group, the odds ratios [95% confidence intervals (CIs)] of macrovascular complications of diabetes were 0.62 (95% CI, 0.27-1.39) for those in the low muscle mass group, 1.12 (95% CI, 0.59-2.11) in the obesity group, and 2.43 (95% CI, 1.16-5.07) in the coexistence of the low muscle mass and obesity group, respectively; the odds ratios (95% CIs) of microvascular complications of diabetes were 0.86 (95% CI, 0.52-1.43) for those in the low muscle mass group, 0.82 (95% CI, 0.53-1.26) in the obesity group, and 1.21 (95% CI, 0.69-2.15) in the coexistence of the low muscle mass and obesity group, respectively. According to our findings, the coexistence of low muscle mass and obesity, rather than low muscle mass or obesity alone, was significantly associated with a higher prevalence of macrovascular complications in hospitalized patients with T2DM. This association was not observed for diabetic microvascular complications.

Computed tomography (CT)-based skeletal muscle vertebral-related index to assess low muscle mass in patients with non-small cell lung cancer.

Patients with lung cancer accompanied by sarcopenia may have a poor prognosis. Normally, low muscle mass associated with sarcopenia is assessed using the skeletal muscle index (SMI). It remains unclear whether the standardized skeletal muscle area (SMA) using 2-dimensional (2D) vertebral metrics (called the skeletal muscle vertebral related index, SMVI) could substitute for SMI when it is missing. The aim of this study was to investigate the feasibility of SMVI as an alternative to SMI, and their associations with overall survival (OS) in patients with non-small cell lung cancer (NSCLC). In this single-center study, a retrospective analysis was conducted on 433 NSCLC patients who underwent computed tomography (CT) scans. At the third lumbar vertebra (L3) level, measurements were taken for SMA, vertebral body area, transverse vertebral diameter (TVD), longitudinal vertebral diameter (LVD), and vertebral height (VH). The 4 SMVIs were skeletal muscle vertebral ratio (SMVR) (SMA/vertebral body area), skeletal muscle transverse vertebral diameter index (SMTVDI) (SMA/TVD2), skeletal muscle longitudinal vertebral diameter index (SMLVDI) (SMA/LVD2), and skeletal muscle vertebral height index (SMVHI) (SMA/VH2). The patients were categorized into low and high muscle mass groups based on SMI, and the differences in SMVIs between the 2 groups were compared to assess their correlation with SMI. Receiver operating characteristic (ROC) curves and the area under the curve (AUC) were utilized to assess the discriminatory ability. Kaplan-Meier curves were employed to compare the survival disparity between the 2 groups. We included 191 male and 242 female patients in this study. Compared to the high muscle mass group, patients in the low muscle mass group exhibited significantly lower SMVR, SMTVDI, SMLVDI, and SMVHI (all P<0.05). All 4 SMVIs showed a positive correlation with SMI, with Spearman correlation coefficients of 0.83, 0.76, 0.75, and 0.67, respectively (all P<0.001). The AUC for diagnosing low muscle mass was higher than 0.8 for all 4 SMVI parameters. The Kaplan-Meier curve revealed that the low-risk group had a better survival probability than the high-risk group in the SMVR, SMTVDI, and SMLVDI. The SMVI functions as an alternative metric for evaluating skeletal muscle mass in the assessment of NSCLC based on SMI.

Low skeletal muscle mass is associated with inferior preoperative and postoperative shoulder function in elderly rotator cuff tear patients

BackgroundThe age-related loss of skeletal muscle mass is an important characteristic of sarcopenia, an increasingly recognized condition with systemic implications. However, its association with shoulder function in elderly patients with rotator cuff tears (RCT) remains unknown. This study aimed to investigate the relationship between low skeletal muscle mass and shoulder function in elderly RCT patients.MethodsA retrospective analysis was conducted on RCT patients who underwent chest computed tomography (CT) scans for clinical evaluation. Preoperative CT scan images of the chest were used to calculate the cross-sectional area (CSA) of thoracic muscle at the T4 level. The medical records were reviewed. Shoulder function was assessed using the ASES score and CMS score both preoperatively and at the final follow-up. Data on the preoperative range of motion (ROM) for the affected shoulder, were collected for analysis. Subgroup analyses by sex were also performed.ResultsA total of 283 RCT patients, consisting of 95 males and 188 females, with a mean age of 66.22 ± 4.89(range, 60–95 years) years were included in this retrospective study. The low muscle mass group showed significantly higher level of c-reactive protein (CRP) and erythrocyte sedimentation rate (ESR) compared to the normal group(3.75 ± 6.64 mg/L vs. 2.17 ± 2.30 mg/L, p = 0.021; 19.08 ± 12.86 mm/H vs.15.95 ± 10.76 mm/H, p = 0.038; respectively). In the normal group, pre-operative passive ROM, including forward elevation, abduction, lateral rotation, and abductive external rotation, was significantly better than that in the low muscle mass group (127.18 ± 34.87° vs. 89.76 ± 50.61°; 119.83 ± 45.76° vs. 87.16 ± 53.32°; 37.96 ± 28.33° vs. 25.82 ± 27.82°; 47.71 ± 23.56° vs. 30.87 ± 27.76°, all p < 0.01, respectively). Similar results were found in the active ROM of the shoulder. The female low muscle mass group exhibited significantly poorer passive and active ROM (p < 0.05). The post-operative ASES scores and CMS scores of the female low muscle mass group were also statistically worse than those of the female normal group (p < 0.05).ConclusionsThe results of present study revealed that the low skeletal muscle mass is associated with inferior ROM of the shoulder and per- and post-operative shoulder function, especially for elderly female patients.

Factors associated with skeletal muscle mass in middle-aged men living with HIV.

Despite extensive research on muscle loss in people living with HIV (PLWH), the prevalence and contributing factors specifically among middle-aged men remain unclear. This study aimed to determine the prevalence of low muscle mass within this demographic and to identify associated factors. A total of 378 men living with HIV were enrolled in the study. They were classified into low muscle mass group if they displayed a skeletal muscle index (SMI) <7.00kg/m2 or fell within the lowest quintile of SMI based on the criteria established by the Asian Working Group for Sarcopenia 2019. Out of the 378 men living with HIV enrolled, 351 had normal muscle mass, while 27 (7.1%) had low muscle mass. Antiretroviral drugs Zidovudine (AZT) (OR=0.246, P=0.022) and higher serum albumin levels (OR=0.899, P=0.026) were found to be protective factors against low muscle mass according to quintile grouping. Strong positive associations between SMI and body mass index (BMI), nutritional risk index (NRI), oedema index and fat-free mass index (FFMI) (R>0.5, P<0.001) were observed. In addition, both BMI (sensitivity=0.741, specificity=0.906) and NRI (sensitivity=0.963, specificity=0.601) had high sensitivity and specificity in diagnosing low muscle mass, with critical values of 19.85 and 114.177 for BMI and NRI, respectively. The oedema index was the most effective measure of body composition in detecting abnormal fluid retention with high sensitivity (92.6%) and moderate specificity (71.8%) in identifying individuals with low muscle mass. Notably, PLWH with low muscle mass participants had a significantly higher prevalence (92.6%) of a high oedema index compared with those with normal muscle mass (28.2%). This observation indicates that individuals with HIV who experience reduced muscle mass is commonly accompanied with abnormal fluid retention within the body. Antiretroviral medication types, specifically Zidovudine, BMI and NRI can be independent risk factors for low muscle mass in men with HIV. These factors, along with BMI, could be used conveniently to predict low muscle mass. Furthermore, the association between the oedema index and muscle mass suggests that observing signs of oedema may indicate a risk of low muscle mass in PLWH.

Association of low muscle mass with cognitive function and mortality in USA seniors: results from NHANES 1999–2002

BackgroundSarcopenia and cognitive impairment have been linked in prior research, and both are linked to an increased risk of mortality in the general population. Muscle mass is a key factor in the diagnosis of sarcopenia. The relationship between low muscle mass and cognitive function in the aged population, and their combined impact on the risk of death in older adults, is currently unknown. This study aimed to explore the correlation between low muscle mass and cognitive function in the older population, and the relationship between the two and mortality in older people.MethodsData were from the National Health and Nutrition Examination Survey 1999–2002. A total of 2540 older adults aged 60 and older with body composition measures were included. Specifically, 17–21 years of follow-up were conducted on every participant. Low muscle mass was defined using the Foundation for the National Institute of Health and the Asian Working Group for Sarcopenia definitions: appendicular lean mass (ALM) (< 19.75 kg for males; <15.02 kg for females); or ALM divided by body mass index (BMI) (ALM: BMI, < 0.789 for males; <0.512 for females); or appendicular skeletal muscle mass index (ASMI) (< 7.0 kg/m2 for males; <5.4 kg/m2 for females). Cognitive functioning was assessed by the Digit Symbol Substitution Test (DSST). The follow-up period was calculated from the NHANES interview date to the date of death or censoring (December 31, 2019).ResultsWe identified 2540 subjects. The mean age was 70.43 years (43.3% male). Age-related declines in DSST scores were observed. People with low muscle mass showed lower DSST scores than people with normal muscle mass across all age groups, especially in the group with low muscle mass characterized by ALM: BMI (60–69 years: p < 0.001; 70–79 years: p < 0.001; 80 + years: p = 0.009). Low muscle mass was significantly associated with lower DSST scores after adjusting for covariates (ALM: 43.56 ± 18.36 vs. 47.56 ± 17.44, p < 0.001; ALM: BMI: 39.88 ± 17.51 vs. 47.70 ± 17.51, p < 0.001; ASMI: 41.07 ± 17.89 vs. 47.42 ± 17.55, p < 0.001). At a mean long-term follow-up of 157.8 months, those with low muscle mass were associated with higher all-cause mortality (ALM: OR 1.460, 95% CI 1.456–1.463; ALM: BMI: OR 1.452, 95% CI 1.448–1.457); ASMI: OR 3.075, 95% CI 3.063–3.088). In the ALM: BMI and ASMI-defined low muscle mass groups, participants with low muscle mass and lower DSST scores were more likely to incur all-cause mortality ( ALM: BMI: OR 0.972, 95% CI 0.972–0.972; ASMI: OR 0.957, 95% CI 0.956–0.957).ConclusionsLow muscle mass and cognitive function impairment are significantly correlated in the older population. Additionally, low muscle mass and low DSST score, alone or in combination, could be risk factors for mortality in older adults.

Exploring the Association between Elevated Anxiety Symptoms and Low Skeletal Muscle Mass among Asymptomatic Adults: A Population-Based Study in Republic of Korea.

Individuals with mental health problems are at higher risk of musculoskeletal diseases. However, the association between low muscle mass (LMM) and anxiety symptoms remains uninvestigated. This cross-sectional study enrolled 174,262 adults (73,833 women, 100,429 men), aged 18 to 89, who completed the anxiety scale and body composition analyses. Using bio-electrical impedance analysis, skeletal muscle mass index (SMI) was calculated based on appendicular skeletal muscle mass (ASM) (kg)/height (m2). LMM was defined as SMI < 7.0 kg/m2 in men and <5.4 kg/m2 in women. Anxiety symptoms were screened using the Clinical Useful Anxiety Outcome Scale (CUXOS) with cut-off scores of 20, 30, and 40. Multivariable logistic regression analyses were performed. LMM prevalence was 20.17% in women, 3.86% in men (p < 0.001). The prevalence of anxiety symptoms in LMM group decreased from mild (CUXOS > 20: women, 32.74%, men, 21.17%) to moderate (CUXOS > 30: 13.34%, 7.32%), to severe anxiety symptoms (CUXOS > 40: 4.00%, 1.73%). In multivariable-adjusted models, LMM was associated with mild (aOR (95% confidence interval)), women, 1.13 (1.08-1.17); men, 1.17 (1.08-1.27)), moderate (1.17 (1.11-1.24); 1.35 (1.19-1.53) and severe anxiety symptoms (1.18 (1.07-1.3), 1.36 (1.06-1.74)), demonstrating an increased risk of ORs with escalating anxiety severity. LMM was independently associated with a higher prevalence of anxiety symptoms.

Utilize multi-metabolic parameters as determinants for prediction of skeletal muscle mass quality in elderly type2 diabetic Chinese patients

BackgroundSarcopenia, an age-related disorder characterized by loss of skeletal muscle mass and function, is recently recognized as a complication in elderly patients with type 2 diabetes mellitus (T2DM). Skeletal muscles play a crucial role in glycemic metabolism, utilizing around 80% of blood glucose. Accordingly, we aimed to explore the relationship between glucose metabolism and muscle mass in T2DM.MethodsWe employed the AWGS 2019 criteria for diagnosing low muscle mass and 1999 World Health Organization (WHO) diabetes diagnostic standards. This study included data of 191 individuals aged 60 and above with T2DM of Shanghai Pudong Hospital from November 2021 to November 2022. Fasting C-peptide (FPCP), fasting plasma glucose (FPG), 2-hour postprandial plasma glucose (PPG) and postprandial 2-hour C-peptide (PPCP), glycated hemoglobin A1c (HbA1c), glycated albumin (GA), serum lipids spectrum, renal and hepatic function, hemoglobin, and hormone were measured. Based on the findings of univariate analysis, logistic regression and receiver operating characteristic (ROC) curves were established.ResultsParticipants with low muscle mass had significantly lower alanine and aspartate aminotransferase, and both FPCP and PPCP levels (P < 0.05). Compared with those without low muscle mass, low muscle mass group had significantly higher FPG, HbA1c, GA levels (P < 0.05). Body fat (BF, OR = 1.181) was an independent risk factor for low muscle mass. PPCP (OR = 0.497), BMI (OR = 0.548), and female (OR = 0.050) were identified as protective factors for low skeletal muscle. The AUC of BMI was the highest, followed by the PPCP, gender and BF (0.810, 0.675, 0.647, and 0.639, respectively), and the AUC of the combination of the above four parameters reached 0.895.ConclusionsIn this cross-sectional study, BMI, Female, and PPCP associated with T2DM were protective factors for low muscle mass. BF was associated with T2DM and risk factor for low muscle mass.

A baseline sarcopenia index based on creatinine/cystatin C for the prediction of stroke recurrence and mortality in older survivors of first ischemic strokes.

Older adults individuals have a higher risk of stroke recurrence, leading to high mortality and disability rates, which, in turn, hinders the achievement of healthy aging. This study aimed to assess the utility of a baseline sarcopenia index (SI) based on serum creatinine (Cr)/cystatin C (CysC) as a prognostic marker for the risk of stroke recurrence and mortality in first-ever ischemic stroke older survivors (ISOS). Data were obtained from an ischemic stroke cohort study. The baseline information was collected from medical records and face-to-face interviews with patients admitted between January 2010 and June 2016. Follow-up information was obtained from telephone interviews every 3 months to determine stroke recurrence and survival status. The SI was calculated from the Cr and CysC values in the medical records as Cr/CysC × 100. Using the first quantile of the SI as the cut-off value, the study participants were divided into the low muscle-mass group (low SI) and the high muscle-mass group (high SI). Cox regression analysis was used to assess the association between SI and recurrence and mortality. A total of 415 first-ever ISOS were enrolled, including 242 (58.31%) male and 173 (41.69%) female participants. In the high-SI group, the relapse and mortality rates were lower than those in the low-SI group (relapse: 20.58% vs. 30.77%; mortality:13.5% vs. 29.81%). After adjusting for confounding factors, the high-SI group was found to have a lower risk of relapse and mortality than the low-SI group (relapse: HR = 0.571; mortality: HR = 0.294). The SI was predictive of the long-term prognosis of IS recurrence and mortality in first-ever ISOS. After discharge, in addition to conventional medication, it is recommended that patients with low SI values actively receive treatment for sarcopenia to reduce the risk of stroke recurrence and mortality and promote healthy aging.

Prognostic value of low muscle mass at the 12th thoracic vertebral level in multiple myeloma treated with transplantation: CAREMM-2101 study.

Autologous hematopoietic stem cell transplantation (ASCT) has been introduced as a standard treatment for newly diagnosed multiple myeloma (NDMM) following novel agent-based induction chemotherapy. This study investigated whether pre-ASCT low muscle mass evaluated using the paraspinal muscle index (PMI) at the 12th thoracic vertebra (T12) level is a reliable prognostic marker in NDMM after chemotherapy. A multi-center registry database was retrospectively analyzed. Between 2009 and 2020, 190 patients with chest computed tomography images underwent frontline ASCT following induction therapy. The PMI was defined as the value of the paraspinal muscle area at the T12 level divided by the square of the patient's height. The cut-off value indicating a low muscle mass was sex-specific, using the lowest quintiles. Of the 190 patients, 38 (20%) were in the low muscle mass group. The low muscle mass group had a lower 4-year overall survival (OS) rate than the non-low muscle mass group (68.5% vs. 81.2%; P = 0.074). The median progression-free survival (PFS) in the low muscle mass group was significantly shorter compared with the non-low muscle mass group (23.3 months vs. 29.2 months; P = 0.029). The cumulative incidence of transplant-related mortality (TRM) was significantly higher in the low muscle mass group than in the non-low muscle mass group (4-year probability of TRM incidence, 10.6% vs. 0.7%; P < 0.001). In contrast, no significant difference in the cumulative incidence of disease progression was found between the two groups. Multivariate analysis revealed that low muscle mass was associated with significant negative outcomes for OS [(hazard ratio (HR): 2.14; P = 0.047], PFS (HR: 1.78; P = 0.012), and TRM (HR: 12.05; P = 0.025). Paraspinal muscle mass may have a prognostic role in NDMM patients who undergo ASCT. Patients with low paraspinal muscle mass have lower survival outcomes compared to non-low muscle mass group.

Nonlinear Association between Physical Function and Risk of Mild Cognitive Impairment in Older Women with Low Muscle Mass

PURPOSE: This study aimed to determine the nonlinear relationship between physical function and body composition in older women with mild cognitive impairment (MCI) and low muscle mass (LMM). Early prediction of sarcopenic MCI is important; however, it remains unclear whether improvements in physical function and cell health promote low rates of sarcopenic MCI in community settings.METHODS: A total of 120 older women were enrolled, and subsequently stratified into the LMM group (n=90) and MCI with LMM group (n=30). MCI was evaluated by a clinician based on global cognitive function and clinical findings.RESULTS: The results of hand grip strength (HGS), short-physical performance battery (SPPB), and 6-minute walk test (6 MWT) were found to be linearly associated with the risk of MCI. This result indicates that endurance capacity in the LMM with MCI group had an adjusted odds ratio of 3.69 (95% CI: 1.11–12.18). The nonlinearity of physical function on the risk of MCI was analyzed using the generalized additive models (GAM).CONCLUSIONS: Physical function and body composition is significantly associated with LMM and MCI risk in aging adults. It is expected that the evaluation and improvement of kinematic indicators, such as HGS, SPPB, endurance, and PhA, could contribute to the prediction and prevention of MCI.

Clinical muscle mass-related biomarkers that predict mortality in older patients with community-acquired pneumonia

ObjectiveCommunity-acquired pneumonia (CAP) is associated with elevated morbidity and mortality, and it usually occurs in older adults. Our goal here was to assess the efficacies of muscle mass-related biomarkers, such as, aspartate transaminase/alanine transaminase (AST/ALT) and creatinine/cystatin C*100 (Cr/CysC*100), in predicting 1-, 2-, and 3-year mortalities of older CAP patients.MethodsDesign: Retrospective cohort study. Setting and Participants: A teaching hospital in western China. Hospitalized CAP patients, aged≥60 years. We separated patients into a high or low muscle mass group, according to the median AST/ALT and Cr/CysC*100, respectively. We acquired data from medical records and local government mortality databases, as well as telephonic interviews. We analyzed the association between low muscle mass (AST/ALT and Cr/CysC*100) and all-cause mortality at 1, 2, and 3 years in older patients with CAP.ResultsWe enrolled 606 patients (58.58% male; median age: 81 years) for analysis. The 1-, 2-, and 3-year mortality in older patients with CAP in the low muscle mass group (AST/ALT) was higher than in the high muscle mass group (AST/ALT) (1-year: 51.16% vs. 36.96%, p < 0.001; 2-year: 54.46% vs. 41.25%, p = 0.001; 3-year: 54.79% vs. 42.9%, p = 0.003). Upon adjustment of potential confounding factors, we revealed, using cox regression analysis, that the low muscle mass group (AST/ALT) experienced enhanced mortality risk at the 1-, 2-, and 3-year follow-ups, compared to the high muscle mass group (AST/ALT) (1-year: hazard ratios (HR) = 1.46, 95% confidence interval (CI): 1.13–1.88; 2-year: HR = 1.39, 95% CI: 1.09–1.77; 3-year: HR = 1.35, 95% CI: 1.06–1.72). The 1-, 2-, and 3-year mortality of older CAP patients in the low muscle mass group (Cr/CysC*100) was also higher than the high muscle mass group (Cr/CysC*100) (1-year: 56.29% vs. 31.91%, p < 0.001; 2-year: 60.26% vs. 35.53%, p < 0.001; 3-year: 61.26% vs. 36.51%, p < 0.001). Compared to the high muscle mass group (Cr/CysC*100), the low muscle mass group (Cr/CysC*100) experienced enhanced mortality risk at the 1-, 2-, and 3-year follow ups (1-year: HR = 1.9, 95% CI: 1.46–2.48; 2-year: HR = 1.85, 95% CI: 1.44–2.39; 3-year: HR = 1.85, 95% CI: 1.44–2.37).ConclusionsLow muscle mass (AST/ALT and Cr/CysC*100) were associated with enhanced 1-, 2-, and 3-year mortality risk in older patients with CAP.

Association of lithocholic acid with skeletal muscle hypertrophy through TGR5-IGF-1 and skeletal muscle mass in cultured mouse myotubes, chronic liver disease rats and humans.

Hepatic sarcopenia is one of many complications associated with chronic liver disease (CLD) and has a high mortality rate; however, the liver-muscle axis is not fully understood. Therefore, few effective treatments exist for hepatic sarcopenia, the best of which being branched-chain amino acid (BCAA) supplementation to help increase muscle mass. Our aim was to investigate the molecular mechanism(s) of hepatic sarcopenia focused on bile acid (BA) composition. The correlation between serum BA levels and psoas muscle mass index (PMI) was examined in 73 CLD patients. Gastrocnemius muscle phenotype and serum BA levels were assessed in CLD rats treated with BCAA. Mouse skeletal muscle cells (C2C12) were incubated with lithocholic acid (LCA), G-protein-coupled receptor 5 (TGR5) agonist or TGR5 antagonist to assess skeletal muscle hypertrophy. In human CLD, serum LCA levels were the sole factor positively correlated with PMI and were significantly decreased in both the low muscle mass group and the deceased group. Serum LCA levels were also shown to predict patient survival. Gastrocnemius muscle weight significantly increased in CLD rats treated with BCAA via suppression of protein degradation pathways, coupled with a significant increase in serum LCA levels. LCA treated C2C12 hypertrophy occurred in a concentration-dependent manner linked with TGR5-Akt pathways based upon inhibition results via a TGR5 antagonist. Our results indicate LCA-mediated skeletal muscle hypertrophy via activation of TGR5-IGF1-Akt signaling pathways. In addition, serum LCA levels were associated with skeletal muscle mass in cirrhotic rats, as well as CLD patients, and predicted overall patient survival. This research was supported by JSPS KAKENHI Grant Number 22K08011 and 21H02892, and AMED under Grant Number JP21fk0210090 and JP22fk0210115. Maintaining cirrhotic rats were partially supported by Otsuka Pharmaceutical Company.

Association between lower parity and low muscle mass in postmenopausal women: data from KNHANES (2010-2011).

This study aimed to investigate whether parity is associated with the prevalence of low muscle mass in postmenopausal women. This study was performed using data from the 2010-2011 Korean National Health and Nutrition Examination Survey, which included 1,338 postmenopausal women aged 46 to 70 years. The association between parity and low muscle mass was analyzed after adjusting parity, multiparity, age, body mass index, diabetes mellitus, education level, and Homeostatic Model Assessment of Insulin Resistance and using weighted multiple logistic regression analysis. Modifiable risk factors were evaluated in a susceptible population. Low muscle mass was defined as an appendicular skeletal muscle mass index below 2 SDs with a cutoff value of 5.45 kg/m 2 . The low muscle mass group ( n = 343) had lower parity, lower body mass index, more frequent previous history of diabetes mellitus, higher Homeostatic Model Assessment of Insulin Resistance, and higher education level compared with the non-low muscle mass group ( n = 995). After adjusting for the confounding factors, parity with three births or more was associated with a significantly lower odds of postmenopausal low muscle mass than nulliparity (model 1: odds ratio, 0.32; 95% confidence interval, 0.12-0.87; P = 0.03; model 2: odds ratio, 0.27; 95% confidence interval, 0.11-0.67; P < 0.05). In the subgroup analysis of the lower parity group, moderate aerobic activity was associated with a lower low muscle mass prevalence. A lower parity is associated with increasing the odds of low muscle mass in postmenopausal Korean women. Moderate aerobic activity may be effective in lowering the odds of low muscle mass in postmenopausal women with lower parity.

Differences in the gut microbiome and reduced fecal butyrate in elders with low skeletal muscle mass

Despite animal studies revealing a causal link between the gut microbiota and skeletal muscle mass, the role of the gut microbiome and its metabolites in humans having low muscle mass remains unclear. Eighty-eight subjects older than 65 years were measured for sarcopenia-related parameters, including body composition, grip strength, gait speed and flexibility. Participants were divided into normal muscle mass group (NM, n=52) and low muscle mass group (LM, n=36) and fresh fecal samples were collected for metagenome and short chain fatty acids (SCFAs) analysis. The richness and evenness of gut microbiota diversity were significantly decreased in the subjects with low muscle mass, including observed ASVs, Shannon and Chao 1 index. A significant difference of gut microbiota profile was noted between NM group and LM group. The Firmicutes/Bacteroidetes ratio was significantly reduced in the LM group. A significant decrease in the abundance of a SCFA-producer, Marvinbryantia spp., whereas a remarkable enrichment of a flavonoid degrader, Flavonifractor spp., was observed in the LM elders. Comparing with the NM group, the fecal butyrate significantly diminished in the LM group and correlated with skeletal muscle mass index. This is the first study that demonstrates the reduced fecal butyrate in elders with low muscle mass and highlights the associated gut microbiome changes. The identified gut microbial features and fecal butyrate level may serve as potential biomarkers for early detection of sarcopenic patients.

Relationship between Muscle Mass of Limbs and aGVHD in Patients with Allogeneic Hematopoietic Stem Cell Transplantation

To explore the correlation of limb muscle mass and acute graft-versus-host disease. Clinical data from 144 patients treated by allo-HSCT in Guangzhou First People's Hospital were collected and analyzed retrospectively. The age, sex, diagnosis, donor age, sex of the donors, preparative regimen, ATG dose, HLA match, graft source, and number of infused stem cells of the patients were collected as baseline information. Meanwhile, bioelectrical impedance principle (BIA) was used to measure the limb muscle mass, body weight, body mass index (BMI), waist-to-hip ratio, upper arm muscle circumference, triceps skinfold thickness, and body fat rate of the patients before and after transplantation, so as to compare the changes of limb muscle mass and investigate its correlation with aGVHD. It was found that 61.11% of allo-HSCT patients showed muscle mass loss, and the proportion of male and female was 35.42% and 25.69%, respectively. There were reduction in the body weight, BMI, upper arm muscle circumference and muscle mass of limbs after transplantation as compared with those before transplantation (P<0.05). By comparing with the cumulative incidence of aGVHD between the patients in low muscle mass group and normal muscle mass group, it was found that the cumulative incidence of Ⅱ-Ⅳdegree aGVHD in patients with low muscle mass (30.38%) was higher than those with normal muscle mass (8.93%), which showed statistical difference (P<0.05). Univariate analysis showed that muscle mass, the sex of the donors, and preparative regimen were the influencing factors of aGVHD (P<0.05). Binary logistic regression showed that low muscle mass was the independent risk factor affecting aGVHD (P<0.05). Patients treated by allo-HSCT shows a decline in muscle mass after transplantation, and the incidence of aGVHD is high in patients with low muscle mass. Therefore, the assessment of muscle quality in early stage in patients with HSCT can facilitate earlier detection of aGVHD.

Difference in sarcopenia characteristics associated with physical activity and disability incidences in older adults.

BackgroundDeteriorated skeletal muscle condition, including sarcopenia, is a risk factor for disability in older adults. Promoting physical activity is a useful treatment for sarcopenia. However, optimal intensity of physical activity according to sarcopenia characteristics is unclear.MethodsThis longitudinal cohort study enrolled 2149 community‐dwelling older adults (women 55.7%, mean age: 75.5 ± 4.0 years). Five‐year disability incidence defined by Japanese long‐term care insurance certification and accelerometer‐measured physical activities (light‐intensity physical activity [LPA] and moderate‐to‐vigorous intensity physical activity [MVPA]), which were adjusted for potential confounders, was analysed using cox‐proportional hazard model stratified by sarcopenia characteristics based on the diagnostic algorithm by the Asian working group for sarcopenia (robust, low physical function, low muscle mass, and sarcopenia). The sarcopenia group was defined as low muscle mass and low physical function (weakness and/or slowness). The low muscle mass and low physical function groups were each defined by these characteristics alone. Muscle mass was analysed via bioelectrical impedance analysis. Each intensity of physical activity times was divided by median values.ResultsThe disability incidence rate was 15.4%, excluding those who could not be followed up. Mean LPA times were 43.8 ± 18.0, 45.6 ± 17.5, 45.4 ± 16.6, 40.8 ± 18.6, and 41.4 ± 18.5 min/day and MVPA times were 24.6 ± 17.6, 26.3 ± 18.3, 27.2 ± 17.3, 21.6 ± 16.3, and 21.5 ± 16.4 min/day in all participants, the robust, low muscle mass, low physical function, and sarcopenia groups, respectively. For all participants, higher MVPA was associated with disability incidence [hazard ratios (HR), 0.63; 95% confidence interval (95% CI), 0.49–0.81; P < 0.001], whereas higher LPA showed no association (HR, 0.86; 95% CI, 0.68–1.10; P = 0.22). Higher LPA was associated in the sarcopenia group (HR, 0.35; 95% CI, 0.15–0.85; P = 0.019), and MVPA was associated in the robust (HR, 0.58; 95% CI, 0.39–0.87; P = 0.008) and low physical function (HR, 0.66; 95% CI, 0.45–0.98; P = 0.040) groups. Both LPA and MVPA showed no association in the low muscle mass group. The P values for interactions between sarcopenia characteristics and physical activity were 0.017 for LPA and 0.014 for MVPA.ConclusionsThe LPA was associated with a lower risk of disability in older adults with sarcopenia, whereas MVPA was associated in subjects with robust and low physical function. Our findings indicate a need for individualized approaches to prevent disability based on muscle condition.

Differences in lower limb muscle strength and balance ability between sarcopenia stages depend on sex in community-dwelling older adults.

This study aimed to compare motor function between sarcopenia stages with respect to sex in community-dwelling older adults. The participants, comprising 2107 community-dwelling older adults (738 men and 1369 women), were classified into 4 groups and the groups were operationally defined-normal, low muscle mass, low physical function, and sarcopenia groups. Lower limb muscle strength and balance ability were assessed for evaluating motor function. To compare motor function between sarcopenia stages, an analysis of covariance adjusted for age and body mass index was performed. Lower limb muscle strengths were significantly lower not only in the sarcopenia group but also in the low muscle mass and low physical function groups than that in the normal group in both men and women. Low hip abductor muscle strength was observed in the low physical function group compared to the low muscle mass group in women, but not in men. Timed Up and Go test results in the sarcopenia and low function groups was lower than in the normal and low muscle mass groups for men and women. One-leg standing in the low physical function group was lower than that in the normal group, only for women. Reduced motor function was observed not only in older people with sarcopenia but also in older people with only low muscle mass or low physical function, and the decline in lower limb muscle strength and balance ability in the low function group were greater in older women than in older men.

Association between preoperative low muscle mass and psychological factors after surgery among patients with lumbar spinal stenosis: A longitudinal study

It remains controversial whether preoperative low muscle mass affects clinical outcomes after lumbar surgery. Previous studies evaluated outcomes such as pain, quality of life, and disability, but none investigated preoperative low muscle mass and psychological factors. The purpose of this study was to clarify the association between preoperative low muscle mass and postoperative psychological factors in lumbar spinal stenosis (LSS). A longitudinal analysis was performed in 85 consecutive preoperative patients with LSS. Demographic data, leg pain, low back pain, Japanese Orthopaedic Association score, Pain Catastrophizing Scale (PCS) score, Fear-Avoidance Beliefs Questionnaire on Physical Activity (FABQ-PA) score, Hospital Anxiety and Depression Scale (HADS) score, walking velocity, grip strength, and appendicular lean mass were assessed. Muscle mass was measured using bioelectrical impedance analysis. Patients were divided into two groups based on skeletal muscle mass index. These clinical outcomes were evaluated preoperatively and 1 year after surgery. In the 73 patients who were analyzed 1 year after surgery, the prevalence of preoperative low muscle mass was 21.9%. The normal muscle mass group showed significantly improved PCS, FABQ-PA, HADS-anxiety, and HADS-depression scores 1 year after surgery. The low muscle mass group did not demonstrate significantly improved PCS, FABQ-PA, or HADS-depression scores, and had a significantly smaller increase in the FABQ-PA score than the normal muscle mass group. Multivariate analysis showed that low muscle mass was significantly related to change in FABQ-PA score. Our results suggest that preoperative low muscle mass hinders improvement in fear-avoidance beliefs 1 year after surgery.

Pre-operative low muscle mass is associated with major complications and lower recurrence-free survival after gastric cancer surgery.

Low muscle mass (LMM) has been associated with post-operative morbidity. This study aimed to examine the relationship between pre-operative LMM and major post-operative complications and survival in patients undergoing curative resection for gastric cancer. A single-centre retrospective cohort study was conducted on consecutive patients who underwent surgical resection for gastric adenocarcinoma between 2008 and 2018. Patient demographics, radiological parameters, pathological data and complications were recorded. Skeletal muscle index was calculated using OsiriX software by manually measuring the cross-sectional skeletal muscle area at the third lumbar vertebra and correcting to the patient's height. Univariate and multivariate analyses were used to identify the risk factors associated with the outcomes. A total of 62 patients (36 males, mean age 68.3 ± 1.5 years) met the inclusion criteria. Twenty-six (41.9%) patients had LMM pre-operatively. Demographic data in the non-LMM and LMM groups were equally matched except for body mass index (27.6 ± 0.8 kg/m2 versus 24.3 ± 1.1 kg/m2 ; P = 0.012) and serum albumin (36.7 ± 0.7 g/L versus 33.8 ± 1.0 g/L; P = 0.017), which were higher in the non-LMM. LMM was associated with higher incidence of total (35.5% versus 64.5%; P = 0.006), minor (40% versus 60%; P = 0.030), major (9.1% versus 90.9%; P = 0.004) post-operative complications and decreased recurrence-free survival (hazard ratio 2.29; 95% confidence interval 1.10-4.77; P = 0.027). LMM is a significant independent risk factor for major post-operative complications and recurrence-free survival after gastrectomy. Pre-operative identification of LMM could be a useful tool for prognostication and may identify a group suitable for prehabilitation.