INTRODUCTION: The diagnosis of sarcopenia relies on key indicators such as handgrip strength, walking speed and muscle mass. Developing a composite index that integrates these measures could enhance clinical evaluation in older adults. This study aimed to standardise and combine these metrics to establish a z score for the sarcopenia composite index (ZoSCI) tailored for the ageing population. Additionally, we explore the risk factors associated with ZoSCI to provide insights into early prevention and intervention strategies. METHOD: This retrospective study analysed data between January 2017 and December 2021 from an elderly health programme in Taiwan, applying the Asian Working Group for Sarcopenia criteria to assess sarcopenia. ZoSCI was developed by standardising handgrip strength, walking speed and muscle mass into z scores and integrating them into a composite index. Receiver operating characteristic (ROC) curve analysis was used to determine optimal cut-off values, and multiple regression analysis identified factors influencing ZoSCI. RESULTS: Among the 5047 participants, the prevalence of sarcopenia was 3.7%, lower than the reported global prevalence of 3.9-15.4%. ROC curve analysis established optimal cut-off points for distinguishing sarcopenia in ZoSCI: -1.85 (sensitivity 0.91, specificity 0.88) for males and -1.97 (sensitivity 0.93, specificity 0.88) for females. Factors associated with lower ZoSCI included advanced age, lower education levels, reduced exercise frequency, lower body mass index and creatinine levels. CONCLUSION This study introduces ZoSCI, a new compo-site quantitative indicator for identifying sarcopenia in older adults. The findings highlight specific risk factors that can inform early intervention. Future studies should validate ZoSCI globally, with international collaborations to ensure broader applicability.
Humans ; Sarcopenia/physiopathology* ; Male ; Aged ; Female ; Retrospective Studies ; Hand Strength ; Taiwan/epidemiology* ; ROC Curve ; Aged, 80 and over ; Risk Factors ; Walking Speed ; Geriatric Assessment/methods* ; Prevalence ; Muscle, Skeletal ; Middle Aged

BACKGROUND

Hand grip strength (HGS) is a tool to measure muscle strength, which is an important component in sarcopenia and frailty. Grip strength (GS) in midlife can predict physical disability in senior years and help evaluate a patient's overall health.

The general purpose of this study is to validate the HGS using an aneroid sphygmomanometer and Jamar dynamometer as a diagnostic tool for sarcpenia. The specific aims of this study are (a) to determine the concurrent criterion validity, (b) to determine the reliability, and (c) to measure the inter-rater agreement of the aneroid sphygmomanometer against the Jamar dynamometer in measuring HGS.

This prospective validation study measures HGS using an aneroid sphygmomanometer and Jamar dynamometer obtained from seventy participants 50 years old and above. Statistical methods used in data analysis include Spearman Rho, univariate linear regression analyses, intra-class correlation, inter-rater reliability, intra-rater reliability, Bland-Altman plots, and Lin’s concordance.

There was a significant correlation of HGS with the Jamar dynamometer and aneroid sphygmomanometer regardless of the rater [Spearman Rho (rs=0.762 to 0.778, p=0.001)]. Jamar GS is comparable to GS using a sphygmomanometer with the formula of [Jamar = 0.54 x sphygmomanometer (mmHg) - 45.12].

Aneroid sphygmomanometer can be used as an option to measure GS and has a valid value to predict the Jamar GS value. Hence, it can be an alternate tool for diagnosing sarcopenia.

BACKGROUND

Curcumin has been investigated as a potential natural solution to prevent or even treat skeletal muscle decline. There are a number of externally sourced finished products (ie, those imported from other countries) containing curcumin, but high cost limits their usage. The emerging research and development of locally sourced curcumin is an opportunity to produce high-quality oral supplements comparable to existing imported products.

The primary purpose of this study is to determine the effects of oral administration of a local curcumin formulation on skeletal muscle using an animal model that similarly demonstrated the course of human sarcopenia.

Purpose-bred 11- to 12-week-old female Sprague Dawley (SD) rats will be used in this study. SD rats are extensively used in animal models of human diseases and conditions such as diabetes, obesity and sarcopenia. Female rats have been selected because they do not demonstrate more temperature or activity variance and have more stable behavior compared to males. To simulate sarcopenia in this animal model, the tail suspension (TS) method was utilized. The TS method involves decreased hind limb function by suspending the animal’s tail for the duration of treatment. The laboratory animals will be randomized to receive any of the four treatments: (1) low-dose curcumin + vehicle; (2) high-dose curcumin + vehicle; (3) vehicle only; and (4) control (distilled water). The interventions will be subdivided into two: 2-week treatment and 4-week treatment. The gastrocnemius muscles on both sides will be excised and weighed, and the muscle tissues subjected to rapid freezing in acetone-dry ice and sliced into 10 μm-thick sections for staining. Examination of muscle architecture and computation of atrophy factors will be performed. The presence of connective tissue, fat tissue and number of atrophic muscle cells will be determined. Accurate quantitative detection of the rat total AMP (adenosine monophosphate)-Activated Protein Kinase will be performed in the gastrocnemius muscle tissue utilizing the enzyme-linked immunosorbent assay kit.

Stroke-associated sarcopenia is a serious post-stroke complication that can have a significant impact on patient’s functional recovery. However， currently available assessment tools for sarcopenia require specialized equipment and personnel， which are difficult to access in resource-limited settings. This article presents the role of biomarkers as an objective method in the pathogenesis， prevention， diagnosis， and prognostic assessment of stroke-associated sarcopenia， with the focus on neuromuscular， inflammatory， metabolic， and nutritional indicators.
Stroke ; Sarcopenia ; Biomarkers

Objective To investigate the incidence rate of sarcopenia and related risk factors in patients with stroke. Methods A retrospective analysis was performed for the patients with stroke who were admitted to the stroke center of a grade A tertiary hospital in Changchun， China， from March 2023 to June 2024. The method of bioelectrical impedance was used to perform body composition analysis for all patients on day（7.0±1.0）after admission， and the incidence rate of stroke-related sarcopenia was analyzed. A binary logistic regression analysis was used to investigate the risk factors for stroke-related sarcopenia. Results A total of 666 patients were included in the study， among whom 150（22.5%） developed sarcopenia （95%CI 0.193‒ 0.257）. Low body mass index， low phase angle， low triglyceride， advanced age， and low Barthel index were risk factors for the early onset of sarcopenia in patients with stroke. Conclusion There is a relatively high incidence rate of sarcopenia in stroke patients， with complex influencing factors. Medical staff should pay more attention to the elderly stroke patients， as well as those patients with emaciation， low phase angle， low triglyceride， and limited activities of daily living. Early nutritional supplementation and functional exercise can help to prevent the onset of stroke-related sarcopenia.
Stroke ; Sarcopenia

The increasing prevalence of aging has led to a rising incidence of comorbidity of sarcopenia and obesity, posing significant burdens on socioeconomic and public health. Current research has systematically explored the pathogenesis of each condition; however, the mechanisms underlying their comorbidity remain unclear. This study reviews the current literature on sarcopenia and obesity in the aging population, focusing on their shared biological mechanisms, which include loss of autophagy, abnormal macrophage function, mitochondrial dysfunction, and reduced sex hormone secretion. It also identifies metabolic mechanisms such as insulin resistance, vitamin D metabolism abnormalities, dysregulation of iron metabolism, decreased levels of nicotinamide adenine dinucleotide, and gut microbiota imbalances. Additionally, this study also explores the important role of genetic factors, such as alleles and microRNAs, in the co-occurrence of sarcopenia and obesity. A better understanding of these mechanisms is vital for developing clinical interventions and preventive strategies.
Humans ; Sarcopenia/physiopathology* ; Obesity/physiopathology* ; Aging/physiology* ; Autophagy/physiology* ; Insulin Resistance ; Comorbidity ; Vitamin D/metabolism* ; Gonadal Steroid Hormones/metabolism* ; Gastrointestinal Microbiome ; Mitochondria ; MicroRNAs

OBJECTIVE: To investigate the effects of sarcopenia on therapeutic response and prognosis of newly diagnosed acute myeloid leukemia (AML) patients, and reveal its predictive value for the clinical outcomes of AML patients. METHODS: A total of 122 AML patients who were initially diagnosed and treated with induction chemotherapy at the Department of Hematology in the Affiliated Hospital of Nantong University from January 2017 to December 2020 were included in this study. The sarcopenia was diagnosed by measuring body composition parameters with multifrequency bioelectrical impedance analyzer, and all AML patients were divided into sarcopenia and non-sarcopenia groups. Kaplan-Meier curves and log-rank test were used to compare the survival difference between the two groups. The relationship between sarcopenia and overall survival (OS) of AML patients was further determined by the univariate and multivariate Cox regression analysis. RESULTS: Among 122 AML patients, 46 (37.7%) were diagnosed with sarcopenia before induction chemotherapy. The body mass index (BMI) of patients with sarcopenia was significantly lower than that of non-sarcopenia patients ( t =4.258, P <0.001), and the complete response (CR) and partial response (PR) rates of sarcopenia patients after induction chemotherapy were significantly lower than those of nonsarcopenia patients (χ²=6.348, P =0.042). Kaplan-Meier curves showed that sarcopenic patients had a shorter OS than non-sarcopenic patients, and the median OS of the two groups were 20.7 (95%CI : 12.6-27.8) months and 27.8 (95%CI : 22.3-31.9) months, respectively (χ²= 5.659, P =0.017). Subgroup analysis indicated that the median OS of sarcopenic and non-sarcopenic AML patients who received standard induction chemotherapy were 12.2 (95%CI : 5.4-24.7) months and 26.1 (95%CI : 16.7-35.4) months, respectively (χ²=3.949, P =0.047). The multivariate Cox regression analysis revealed that sarcopenia (HR=1.671, 95%CI : 1.034-2.701, P =0.036) was an independent predictor for poor prognosis in AML patients. CONCLUSION Sarcopenia is significantly associated with low response rate of induction chemotherapy and poor prognosis in AML patients, and it might be an useful tool for predicting the clinical outcome of AML patients.
Humans ; Sarcopenia/complications* ; Leukemia, Myeloid, Acute/diagnosis* ; Prognosis ; Male ; Female ; Induction Chemotherapy ; Middle Aged ; Body Mass Index ; Kaplan-Meier Estimate

BACKGROUND AND AIM: The association between physical activity (PA) and sarcopenia has mostly been investigated in older people, with few studies focused on earlier life stages. The present study aimed to determine whether higher PA levels are associated with a lower sarcopenia risk in middle-aged and early older people. METHODS: This was an 8-year follow-up study. Participants were 6,500 community-dwelling adults aged 40-74 years who participated in the baseline questionnaire survey conducted in 2011-2014 in Japan. Levels of total and leisure-time PAs at baseline were assessed using validated metabolic equivalent scores. Multi-frequency bioelectrical impedance analysis and handgrip strength measurement were performed in 2021-2022, and participants with low height-adjusted appendicular lean mass (<20th percentile) and low grip strength were diagnosed as having sarcopenia (outcome). Covariates were demographics, body size, lifestyle, and disease history at baseline. RESULTS: The prevalence of sarcopenia was 137/2926 (4.7%) for men and 127/3574 (3.6%) for women. Higher total PA levels were associated with lower odds of sarcopenia (P for trend = 0.0278), with the second highest group having a significantly lower OR (0.51) than the lowest group (reference) in women, but not in men. Regarding leisure-time PA, those engaged in leisure-time vigorous PA had a lower OR of sarcopenia than those who did not (OR = 0.67, P = 0.0625). CONCLUSION Higher levels of total PA are associated with a lower risk of sarcopenia in women but not in men, suggesting a sex difference in this association. In addition, high levels of vigorous leisure-time PA may be effective for preventing sarcopenia.
Humans ; Sarcopenia/epidemiology* ; Japan/epidemiology* ; Male ; Female ; Middle Aged ; Aged ; Follow-Up Studies ; Independent Living/statistics & numerical data* ; Exercise ; Adult ; Prevalence ; Risk Factors ; Hand Strength ; East Asian People

BACKGROUND: Cardiovascular disease (CVD) is the predominant cause of mortality in China. However, the mechanisms linking sarcopenia to CVD remain poorly understood, particularly in normal-weight populations. Individuals with the absence of overweight or obesity may tend to experience missed opportunities for timely intervention. This study aimed to investigate the longitudinal association between sarcopenia and incidence of new-onset CVD in a normal-weight population, and to examine the mediating effect of functional limitation in this relationship. METHODS: We conducted a closed-cohort analysis using a nationwide sample of 4,147 middle-aged and older adults with normal weight in China. We performed Cox proportional hazards regression analysis to explore the associations of baseline sarcopenia with incident CVD. The difference method was applied to estimate the mediation proportion of functional limitation in this association. RESULTS: Over a mean follow-up period of 7.62 years, CVD occurred in 835 participants. In the multivariable-adjusted Cox model, individuals with sarcopenia exhibited a significantly higher likelihood of developing incident CVD compared to those without sarcopenia (adjusted hazard ratio [aHR] = 1.45, 95% confidence interval [CI]: 1.21-1.73, P < 0.001). Similar associations were observed for the incidence of heart disease and stroke. Functional limitation accounted for approximately 15.0% of the total effect of sarcopenia on incident CVD (P < 0.001). CONCLUSIONS Sarcopenia exerts both direct and indirect effects on incident CVD among middle-aged and older adults who are normal weight, with functional limitation serving as a significant mediator. Interventions targeting both sarcopenia and functional limitation may offer a promising strategy for enhancing cardiovascular health in this population.
Humans ; Sarcopenia/complications* ; China/epidemiology* ; Male ; Female ; Middle Aged ; Cardiovascular Diseases/etiology* ; Aged ; Incidence ; Cohort Studies ; Proportional Hazards Models ; Risk Factors ; Aged, 80 and over ; Longitudinal Studies

BACKGROUND: Exposure to air pollution and adherence to a healthy lifestyle have been identified to be related to sarcopenia. However, the interactive effects between these two factors remain insufficiently elucidated. The present study was designed to investigate the potential interaction exposure to air pollution with healthy lifestyle on the risk of developing sarcopenia. METHODS: In the retrospective cohort study, all data was extracted from China Health and Retirement Longitudinal Study. Household air pollution was assessed based on the utilization of solid fuels for cooking and heating. A lifestyle score was constructed comprising information on physical activity, smoking, drinking and sleeping time. Multivariate logistic regression model was used to assess the effects of household air pollution and healthy lifestyle score on sarcopenia, separately. We further explored the additive interaction between household air pollution and healthy lifestyle score to sarcopenia using the interaction table developed by T Anderson. Relative excess risk due to interaction (RERI), attributable proportion (AP), and synergy index (SI) were used to evaluate the additive interactive effect. RESULTS: 2,114 participants were included in this study. The result indicated that exposed to household air pollution [adjusted relative risk (RR) = 1.80, 95% confidence interval (CI): 1.15-2.94] and unhealthy lifestyle (adjusted RR = 1.46, 95%CI: 1.04-2.03) were both significantly associated with increased risk of sarcopenia. Furthermore, participants exposed to both household air pollution and an unhealthy lifestyle exhibited a significantly higher risk of sarcopenia relative to those without household air pollution exposure and maintaining a healthy lifestyle (adjusted RR = 2.44). But RERI, AP, and SI suggested that there is no statistically significant additive interaction between household air pollution exposure and healthy lifestyle factors in relation to sarcopenia risk. CONCLUSION Household air pollution in conjunction with an unhealthy lifestyle confers a significantly higher risk of sarcopenia compared to either factor in isolation, with no evidence of a significant additive interaction between these two risk factors.
Humans ; China/epidemiology* ; Male ; Sarcopenia/etiology* ; Female ; Longitudinal Studies ; Middle Aged ; Aged ; Air Pollution, Indoor/adverse effects* ; Retrospective Studies ; Healthy Lifestyle ; Risk Factors ; Environmental Exposure/adverse effects* ; Cooking ; Aged, 80 and over