Age-related and disease-related muscle loss: the effect of diabetes, obesity, and other diseases

Bidirectional association between sarcopenia and depression: A systematic review and meta-analysis

PURPOSE

Recent research has reported a potential bidirectional association between sarcopenia and depression, yet systematic evidence supporting this relationship is still lacking. This study evaluated the bidirectional association of sarcopenia with depression to provide reliable evidence for the development of specific prevention and control strategies.

METHODS

Relevant articles were extracted from PubMed, Embase, Cochrane, and Web of Science from inception to July 4, 2024. Quality was assessed using the Newcastle-Ottawa Scale (NOS) for cohort and case-control studies, and the Joanna Briggs Institute (JBI) Critical Appraisal Checklist for cross-sectional studies. Changes in the association between sarcopenia and depression were compared across different study designs, sources of study subjects, and sarcopenia diagnostic criteria by subgroup analyses. Meta-analysis was conducted using R 4.4.1.

RESULTS

Thirty-three original studies involving 119,421 subjects were incorporated into this review. Pooled analysis revealed a significant reciprocal relationship between sarcopenia and depression in community populations. The risk of depression increased when sarcopenia was the exposure factor [OR = 2.40(95 % CI: 1.87, 3.08)]. Conversely, the risk of sarcopenia significantly increased when depression was the exposure factor [OR = 1.90(95 % CI: 1.44, 2.50)]. Additionally, there was a markedly increased risk of sarcopenia when depressive symptoms were the exposure factor [OR = 1.38(95 % CI: 1.25, 1.53)]. Similar conclusions were obtained in patients with other diseases.

CONCLUSIONS

The significant bidirectional association between sarcopenia and depression enhances the prevention, screening, diagnosis, and treatment of depression, thereby improving quality of life and outcomes.

Role of brain-derived neurotrophic factor in frailty: From mechanisms to interventions

Frailty is a common medical syndrome which largely increases the risk of disability, depression, falls, hospitalization and mortality. An increasing number of research suggests that frailty is reversible by medical interventions at its early stage. Therefore, efficient detection is utterly important for frail population. Since numerous biological processes have been indicated in frail population, the critical regulators in these biological processes could provide biomarkers for early detection or treatment for frailty. The brain-derived neurotrophic factor (BDNF) has been associated with several biological process ranging from cognitive function to inflammation, therefore it could be an important regulator for frailty. In this review, we would discuss the mechanism association between different indicators of frailty and BDNF. Furthermore, we summarize the approaches to interfere with BDNF in healthy and pathologic condition, which could lead to identification of potential interventional strategies for frailty.

High fat diet induces differential age- and gender-dependent changes in neuronal function in Drosophila linked to redox stress

The prevalence of neurodegenerative diseases, such as Alzheimer's and Parkinson's disease, is steadily increasing, thus posing significant challenges to global healthcare systems. Emerging evidence suggests that dietary habits, particularly consumption of high-fat diets, may play a pivotal role in the development and progression of neurodegenerative disorders. Moreover, several studies have shed light on the intricate communication between the gut and the brain, linking gut health with neuroinflammation and its involvement in neurodegenerative processes. This study aims to assess the effects of a high-fat dietary intake on various aspects of neuronal function during aging in a gender specific manner to help understand the potential contributions of diet to neuronal function. To investigate the effects of a high-fat diet, Drosophila melanogaster was used and exposed to a standard normal food diet (NF) and a high-fat diet (HF). Adults were grouped at 10 and 45 days of age in male and female flies reared under the same conditions starting the HF diet at 5 days of age with data showing differential gender- and HF diet-induced phenotypes. Malondialdehyde (MDA) levels were higher in males at 10 and 45 days (p < 0.05), caspase-3 expression increased at 45 days (p < 0.01) implicating apoptosis induction and a reduced climbing activity at 10 and 45 days was apparent in females only (p < 0.01). Adult lifespan under both dietary conditions was unchanged when reared at 18°C but odour-associated learning ability was reduced in larvae reared in a HF diet throughout their development (p < 0.05). This is the first study to characterise effects of a HF diet on neuronal phenotypes in an age- and gender-specific manner in a Drosophila model. Our findings suggest a HF diet induces differential effects of neuronal dysfunction with age and sex-specific outcomes, characterised by enhanced oxidative stress and cell death impacting on behaviour.

Effect of olive oil consumption on diabetes risk: a dose-response meta-analysis

BACKGROUND

Diabetes is a common metabolic disease worldwide, is also a global major public health problem. We carried out this meta-analysis to evaluate the effects of olive oil(OO) consumption on diabetes.

METHODS

PubMed, Embase, Scopus, Web of Science and Cochrane Library databases were systematically searched until October 2024. Heterogeneity among studies was examined using Q and I2 statistics. Combined risk ratio (RR) with their 95% confidence interval (CI) were calculated by using a random effects model. Also dose-response analysis and subgroup analysis were performed.

RESULTS

10 studies (4 cohorts and 6 RCT) involved more than 50,0000 subjects and 2,0000 individuals with diabetes were included in the meta-analysis. A 13% (RR = 0.87, 95%CI = 0.83 - 0.92, P < 0.01) decreased risk of diabetes was shown in Cohort study and 22% (RR = 0.78, 95%CI = 0.70 - 0.88, P < 0.01) decreased risk in RCT study for the highest vs. lowest olive oil consumption. Subgroup analysis results showed that there was a better effect on reducing diabetes risk in age > 50 years(RR = 0.77, 95%CI = 0.70 - 0.89, P < 0.01), Europe(RR = 0.81, 95%CI = 0.72 - 0.86, P < 0.01) and extra virgin olive oil ( RR = 0.75, 95%CI = 0.65-0.87, P < 0.01). Dose-response analysis showed a significant nonlinear association of diabetes risk with OO intake(Pnon-linearity < 0.05) and when 10-20 g of olive oil is consumed daily, the effect amount is statistically significant, while more than 20 g there was not statistically significant. Begg's and Egger's regression test results indicated that there was no publication bias and the results were reliable.

CONCLUSIONS

Evidence from this meta-analysis suggested that OO consumption is associated with a decreased risk of diabetes, especially, 10-20 g OO daily may be beneficial for prevention and management of diabetes.

Higher prognostic nutritional index is associated with lower incidence of sarcopenia

Sarcopenia is a syndrome of progressive, generalized decline in skeletal muscle function and muscle mass. As one of the key factors affecting sarcopenia, nutritional status plays an important role in the occurrence and development of sarcopenia. Therefore, this study selected the National Health and Nutrition Examination Survey (NHANES) database to study the effect of prognostic nutritional index (PNI) on sarcopenia. A total of 8058 adults were included in this study. In multiple linear regression analysis, PNI levels were significantly negatively associated with sarcopenia [0.89 (0.85,0.93)]; The risk of sarcopenia was reduced by 52% in the highest quartile of PNI compared with the lowest quartile [0.48 (0.31,0.74)]; This negative association was sustained in stratified subgroups. According to the generalized additive model and the results of smooth curve fitting, PNI was negatively associated with sarcopenia. Higher PNI was associated with a lower incidence of sarcopenia.

Sirt2 deficiency aggravates intramuscular adipose tissue infiltration and impairs myogenesis with aging in male mice

Sarcopenia, closely associated with other diseases such as diabetes, metabolic syndrome, and osteoporosis, significantly impacts aging populations. It is characterized by muscle atrophy, increased intramuscular adipose tissue, impaired myogenesis, chronic low-grade inflammation, and reduced muscle function. The mechanisms behind aging muscle remain incompletely understood. This study aims to elucidate the role of Sirt2 in the aging process of skeletal muscles and enhance our understanding of the underlying mechanisms. Sirt2 expression was reduced in aging muscle of male mice by 40%, compared to young muscle. Aged male Sirt2 knockout mice exhibit increased intramuscular adipose tissue infiltration by 8.5-fold changes. Furthermore, the deletion of Sirt2 exacerbated myogenesis impairment in aged muscle by decreasing the expression of Pax7 (50%) and NogoA (80%), compared to age- and sex- matched counterparts, emphasizing the role of Sirt2 in pathology of aging muscle. Additionally, long-term Sirt2 deletion affected other Sirtuin subfamily members, with decreased expressions of Sirt1 (65%), Sirt4 (94%), and Sirt5 (71%), and increased expressions of Sirt6 (4.6-fold) and Sirt7 (2.8-fold) in old male Sirt2 knockout mice, while there was no difference of these gene expression in young male mice. This study underscores the critical need for a deeper investigation into Sirt2, promising new insights that could lead to targeted therapies for sarcopenia, ultimately improving the quality of life in the elderly.

Prevalence and coexistence of locomotive syndrome with reduced mobility and metabolic syndrome: a cross-sectional study of 35,059 Japanese adults

Metabolic syndrome (MetS), marked by visceral obesity, hypertension, hyperglycemia, and dyslipidemia, elevates cardiovascular risk. Locomotive syndrome (LS), characterized by age-related mobility decline, often precedes frailty and sarcopenia. We investigated the prevalence and association between MetS and LS among Japanese middle-aged and older adults. This retrospective cross-sectional study was conducted using clinical records of 35,059 Japanese adults who underwent health check-ups between April 2021 and March 2022. MetS was diagnosed using the modified National Cholesterol Education Program Adult Treatment Panel III criteria, and LS was assessed using the LS risk test, which includes the stand-up test, two-step test, and the 25-question Geriatric Locomotive Function Scale. Among the participants, 2640 (7.5%) were diagnosed with MetS, and 5265 (15.0%) were classified as LS-positive. The prevalence of LS was significantly higher in individuals with MetS. The association between MetS and LS remained significant after adjusting for age and sex. We found that LS prevalence was higher in women than in men, though the primary association between MetS and LS remained consistent across both sexes. This large-scale real-world analysis emphasizes the need for integrating LS screening into routine check-ups to detect and manage MetS, aiding in the prevention of functional decline in aging populations.

Visceral adiposity index, premature mortality, and life expectancy in US adults

IMPORTANCE

Visceral adiposity index (VAI) vividly reflects body fat distribution through comprehensively integrating body mass index, sex, waist circumference, triglycerides, and high-density lipoprotein cholesterol. While VAI is an established predictor of various clinical outcomes, its relationship with premature mortality and life expectancy remains unclear.

OBJECTIVE

To explore the association between VAI and premature mortality or life expectancy in a nationally representative cohort of US adults.

METHODS

This study included adults who participated in the National Health and Nutrition Examination Survey (NHANES) from 1999 to 2018, linked to the National Death Index through December 31, 2019. Data were analyzed from August to October, 2024. VAI was categorized into quartiles from the lowest Q1 to the highest Q4. Primary endpoints were premature mortality (death before 80 years of age) and life expectancy.

RESULTS

A total of 43,672 participants (women: 22,164; men: 21,508) aged > 20 years were included. Over a median follow-up of 9.2 years (IQR: 4.9-13.8), 3,187 premature deaths were documented. Higher VAI quartiles were significantly associated with increased multi-adjusted premature mortality risk compared to Q1 (Q3 vs. Q1: hazard ratio [HR], 95% confidence interval [CI]: 1.30, 1.05 to 1.61; Q4 vs. Q1: 1.68, 1.34 to 2.11). This association was particularly pronounced in women (Q3 vs. Q1: 1.53, 1.01 to 2.30; Q4 vs. Q1: 2.36, 1.52 to 3.68), with significant linear trends (P < 0.001). Estimated life expectancy at age 40 years was 41.45 (95% CI: 41.24 to 41.66), 41.32 (41.11 to 41.53), 40.55 (40.35 to 40.75), and 39.26 (39.08 to 39.45) years in Q1, Q2, Q3, and Q4 of VAI, respectively. By sex, estimated life expectancy at age 40 in Q4 was reduced by 3.33 years in women and 1.24 years in men, compared to Q1. By race and ethnicity, it was shortened by 3.90 years in Black participants and 1.68 years in White participants in Q4 group, compared to Q1.

CONCLUSIONS

In this nationwide cohort study, higher VAI was significantly associated with an increased risk of premature mortality and reduced life expectancy at age 40 among US adults. These associations we heterogeneous by sex, race and ethnicity, more pronounced in women and Black participants.

Association of Dietary Inflammation Index with sarcopenia in adult women with nonalcoholic fatty liver disease: based on the National Health and Nutrition Examination Survey Database

BACKGROUND

A higher Dietary Inflammatory Index (DII) is linked with an elevated risk of sarcopenia, but the relationship between the two in adult female patients with nonalcoholic fatty liver disease (NAFLD) remains uncertain.

OBJECTIVE

The project was designed to probe into the relationship between DII and the risk of sarcopenia in adult female NAFLD patients.

METHODS

As a cross-sectional study, this study used NAFLD data for adult women from the 2017 to 2018 National Health and Nutrition Examination Survey (NHANES) Database, with DII as the independent variable and sarcopenia as the dependent variable. The relationship between DII and sarcopenia was examined by utilizing weighted logistic regression. Restricted cubic splines (RCS) and threshold effect models were further employed to explore the nonlinear relationship between the two.

RESULTS

We included 469 NAFLD patients, of whom 65 (10.2%) were sarcopenic. In adult female NAFLD patients, a great positive correlation of DII with the risk of sarcopenia was observed in the weighted logistics regression model [odds ratio (OR): 1.459, 95% confidence interval (CI): 1.013-2.103, P  = 0.045]. The RCS curve manifested a linear correlation between the two ( Pnonlinear  = 0.751). The threshold analysis demonstrated that when DII > 0, DII was positively linked with an elevated risk of sarcopenia (OR: 1.328, 95% CI: 1.030-1.722, P  = 0.030).

CONCLUSION

In adult female NAFLD patients, DII is positively linked with the risk of sarcopenia. Future research should further explore the mechanism of influence of DII on sarcopenia in NAFLD patients and evaluate whether improving eating habits can effectively reduce the occurrence of sarcopenia in women with NAFLD.

Urinary titin as a biomarker of sarcopenia in diabetes: a propensity score matching analysis

PURPOSE

Measuring urinary titin levels is expected to be useful in screening for muscle damage or injury in various diseases. We evaluated whether urinary titin levels were elevated in individuals with type 2 diabetes mellitus (T2DM) and how urinary titin levels were associated with the diagnosis of sarcopenia in T2DM.

METHODS

We performed a cross-sectional analysis of 114 controls and 515 patients with T2DM. Multivariate-adjusted models were used to determine the odds ratios (OR) of urinary titin cutoff values for diagnosing sarcopenia.

RESULTS

Urinary titin levels were higher in the T2DM group than in the non-diabetes group after propensity score matching (median [IQR] 3.2 [2.3, 4.6] vs. 4.4 [2.7, 6.9] pmol/mg·creatinine). T2DM was associated with high titin levels after correction for comorbidities (odds ratio 2.46, 95% confidence interval (CI) 1.29-4.70, P = 0.006) but not after correction for sarcopenia-associated factors. Urinary titin levels above the cutoff value showed an odd ratio of 6.61 (age- and body mass index-adjusted, 1.26-34.6, P = 0.021) for the diagnosis of sarcopenia in men with T2DM aged ≥ 75 years.

CONCLUSION

Results indicated that T2DM was associated with a high-titin state and that the urinary titin cutoff value could be useful for identifying candidates at high risk for sarcopenia, such as elderly men.

The association between sedentary lifestyle and the prevalence of sarcopenia with the mediation role of systematic inflammation index, 25-hydroxyvitamin D, and testosterone: A nationwide cross-sectional study

BACKGROUND

While there is some evidence of the association between sedentary behavior and sarcopenia risk, it remains unclear whether systematic inflammation index (SII), 25(OH)D, and testosterone can mediate this association. This study aims to investigate whether sedentary behavior is associated with the prevalence of sarcopenia in the US population and further examine its potential mediators which have not been thoroughly explored, thereby presenting a novel approach to understanding the mechanism between sedentary behavior and sarcopenia.

METHODS

We conducted a cross-sectional study involving a representative sample of the US national population of 9902 adults aged 18 years or older from the National Health and Nutrition Examination Survey (NHANES) 2011-2018. The participants with sarcopenia were identified by Dual-energy X-ray (DXA) absorptiometry. Weighted multivariable logistic regressions based on the complex survey designs were used to explore the associations between a sedentary lifestyle and the risk of sarcopenia and restricted cubic spline (RCS) regression was used to examine the non-linear association. Causal mediation analysis using the quasi-Bayesian Monte Carlo method was applied to identify the mediating role of SII, 25(OH)D, and testosterone as potential mediators.

RESULTS

A total of 358 participants (3.6 %) had sarcopenia. Compared to those in the lowest quartile of sedentary time, participants in the highest quartile had a hazard ratio of 1.631 (95 % CI: 1.162 to 2.289) for the prevalence of sarcopenia. A non-linear relationship (P for non-linearity <0.001) between sedentary time and the risk of sarcopenia was observed using the RCS method. The odds ratio for sarcopenia was highest (OR = 3.427) when the sedentary time was 1080 min daily. Furthermore, SII, 25(OH)D, and testosterone showed a significant mediation in the association between sedentary time and sarcopenia risk, with a mediation effect of 3.39 %, 10.3 %, and 8.56 %, respectively.

CONCLUSIONS

This study demonstrated novel findings of the association between sedentary behavior and sarcopenia in the US population. Our study found that sedentary time was associated with the prevalence of sarcopenia. Vitamin D, SII, and testosterone served as mediating factors in the association of sedentary time with the risk of sarcopenia.

Impact of Bariatric and Metabolic Surgery on Sarcopenia-Related Parameters According to the EWGSOP2 Consensus Criteria in Persons Living with Obesity

Although bariatric and metabolic surgery (BS) has proved effective in the treatment of obesity based on the reduction in fat mass and the remission of comorbidities, there is also loss of lean mass after BS which could compromise muscle functionality. According to the European Working Group on Sarcopenia in Older People (EWGSOP), sarcopenia is a disease associated with loss of muscle mass, strength, and function. Through a comprehensive review of the literature, we identified a range of studies focusing on evaluating sarcopenia-related parameters according to the EWGSOP2 consensus criteria, before and after BS. Although most studies reported reductions in skeletal muscle mass and absolute muscle strength after surgery, improvements in muscle functionality were generally achieved, independent of the type of BS.

Low appendicular skeletal muscle mass is associated with the risk of mortality among adults in the United States

Low skeletal muscle mass has been shown to be a predictor of mortality, but very few studies have focused on the association between appendicular skeletal muscle mass and mortality risk in a large sample. This study aimed to determine the associations of low appendicular skeletal muscle mass with all-cause and cause-specific mortality in an adult population in the United States. Data were retrieved from 21,938 participants aged 20-85 years from the National Health and Nutrition Examination Survey (NHANES) (1999-2006 and 2011-2018) and merged with the Public-use Linked Mortality File of 2018. The appendicular skeletal muscle mass index (kg/m2) was determined by the skeletal muscle mass in the arms and legs (in kg) and divided by the square of the height (in meters) 2 (kg/m2). Sex-specific quintiles were then used to categorize the appendicular skeletal muscle mass index. The major outcome in this study was mortality from all causes, and the secondary outcome was mortality from heart disease or cancer. Cox proportional hazards models were used to calculate hazard ratios, and 95% confidence intervals for all-cause and competing risk regression analyses were performed to analyze heart disease mortality and cancer mortality. During a 10.9-year median follow-up, 1632 males and 1253 females died. Compared with those of the 5th quintile of the skeletal muscle index, the fully adjusted HRs (95% CIs) of all-cause mortality were 0.81 (0.72-0.92), 0.63 (0.52-0.76), 0.52 (0.43-0.63), and 0.65 (0.52-0.81) for the 1st, 2nd, 3rd, and 4th quintiles of the skeletal muscle index, respectively. A 20-percentile increase in the appendicular skeletal muscle index was associated with a lower risk of all-cause mortality (HR, 0.86; 95% CI, 0.81-0.91) (P < 0.001 for trend) and a lower risk of cancer mortality (HR, 0.87; 95% CI, 0.78-0.96) (P = 0.009 for trend). High appendicular skeletal muscle mass was associated with decreased all-cause mortality and cancer mortality in adults, and interventions aimed at maintaining appropriate appendicular skeletal muscle mass may help prevent premature death.

Nutritional Approach to Diabetic Sarcopenia: A Comprehensive Review

PURPOSE OF THE REVIEW

The aim of this review is to discuss and evaluate diabetic sarcopenia (DS) and its relationship with nutrition by discussing the mechanisms of diabetic sarcopenia in detail and comprehensively reviewing the literature.

RECENT FINDINGS

Type 2 diabetes (T2DM) affects approximately 25% of people aged 50 years and over and indicates a significant the cost of health for the elderly. Nutrition is an important part of these treatment approaches, and in this review, the literature was comprehensively reviewed, focusing on understanding the mechanisms of DS and discussing its relationship with nutrition. A comprehensive search was conducted on Web of Science, Google Scholar, Scopus, Science Direct, and PubMed from inception up to July 2024. The aim of nutritional treatment for DS is to improve muscle mass, muscle strength and physical performance while improving diabetes-related metabolic risk and glucose levels. In this context, it is important to determine energy intake in individuals with DS according to calorie intake exceeding 30 kcal/kg. For these individuals, a protein intake of at least 1-1.2 g/kg/day is recommended, with an emphasis on the number and timing of meals and a nutritional pattern rich in branched chain amino acids (BCAA). In addition, it is important to adopt a diet rich in antioxidants and to choose diet patterns that contain sufficient levels of macro and micronutrients. The Mediterranean diet model can be a good diet option for individuals with DS. Comprehensive studies in this field are needed so that clinicians can make specific dietary recommendations for DS.

Amelioration of aging-induced muscular decline by black soybean (Rhynchosia nulubilis) and black rice (Oryza sativa L.) extracts

Aging leads to a decline in the mass and function of skeletal muscles, a condition known as sarcopenia. It was previously reported that aging-related alterations in protein degradation, chronic inflammation, and deterioration of mitochondrial metabolism affect the acceleration of muscle atrophy in the elderly. However, the detailed mechanism or substantial causes for age-related muscle loss are still lacking, yet exercise or an increment in dietary protein intake are suggested as effective approaches to mitigate muscle atrophy. This study aims to investigate the regulatory effect of black soybean (Rhynchosia nulubilis) and black rice (Oryza sativa L.) mixture extract (BBME), which are rich in protein and bioactive compounds, in 12-month-old aged mice and L6 myotubes. BBME was orally administered at 300 and 600 mg/kg/day (low and high doses) for 12 weeks, and its effects on systemic glucose homeostasis and skeletal muscle metabolism were evaluated. Consequently, BBME at a high dose marginally ameliorated muscle loss and significantly improved glucose metabolism. BBME also reduced cellular senescence markers and enhanced mitochondrial biogenesis in aged skeletal muscles. Additionally, BBME exerted insulin-like activity by promoting glucose metabolism in L6 myotubes. These findings suggest the potential of BBME as a functional food ingredient in alleviating aging-induced muscle loss by modulating mitochondrial activity and glucose metabolism.

Frailty incidence by diabetes treatment regimens in older adults with diabetes mellitus in the ASPirin in Reducing Events in the Elderly Study

Diabetes mellitus is a major risk factor for frailty in older adults, and studies suggest that frailty risk may differ by diabetes treatment regimen. To investigate the association between diabetes medication use and frailty, we conducted an observational cohort analysis of older adults with diabetes enrolled in the ASPirin in Reducing Events in the Elderly (ASPREE) study. Diabetes at baseline (N = 2045) was defined as self-reported diabetes, fasting blood glucose levels > 125 mg/dL, or use of diabetes medication. Diabetes medication exposure at baseline was categorized as use of metformin only (monotherapy) (N = 545), metformin combined with other diabetes medications (N = 420), other diabetes medications only (N = 200), or no diabetes medications (N = 880). Frailty was defined using a modified Fried frailty phenotype (presence of ≥ 3 of 5 criteria) and a deficit accumulation frailty index (FI, score > 0.21/1.00). Mixed effects ordinal logistic regression models revealed the odds of frailty at baseline were highest for the other diabetes medications only group, but this difference remained consistent over follow-up. After adjustment for covariates, including baseline pre-frailty, no differences in the rates of Fried or FI frailty were observed among the diabetes medication exposure groups. These findings suggest that diabetes medication exposure in older adults with diabetes does not directly impact frailty risk.

Risk factors and an optimized prediction model for urosepsis in diabetic patients with upper urinary tract stones

To identify independent risk factors for urosepsis in diabetic patients with upper urinary tract stones (UUTS) and develop a prediction model to facilitate early detection and diagnosis, we retrospectively reviewed medical records of patients admitted between January 2020 and June 2023. Patients were divided based on the quick Sequential Organ Failure Assessment (qSOFA) score. The least absolute shrinkage and selection operator (LASSO) regression analysis was used for variable selection to form a preliminary model. The model was optimized and validated using the receiver operating characteristic (ROC) curve, the Hosmer-Lemeshow test and calibration curve, and decision curve analysis (DCA). A nomogram was constructed for visualization. A total of 434 patients were enrolled, with 66 cases and 368 controls. Six optimal predictors were identified: underweight, sarcopenia, poor performance status, midstream urine culture, urinary leukocyte count, and albumin-globulin ratio (AGR). The midstream urine culture was excluded due to its inability to provide rapid results. The final model demonstrated good prediction accuracy and clinical utility, with no significant difference in performance compared to the initial model. The study developed a prediction model for urosepsis risk in diabetic patients with UUTS, presenting a convenient tool for timely diagnosis, particularly in non-operated patients.

Association of sarcopenia index, based on serum creatinine and cystatin C, with incident diabetes mellitus

BACKGROUND

Sarcopenia, characterized by loss of muscle mass and strength, has been linked to various health outcomes, including diabetes mellitus. This study aims to investigate the association of sarcopenia index, based on serum creatinine and cystatin C levels, with incident diabetes mellitus in middle-aged and older adults in China.

METHODS

This study extracted data from 2015 to 2020 China Health and Retirement Longitudinal Study (CHARLS), including age ≥ 45-year adults without diabetes mellitus at baseline. Sarcopenia index was calculated based on serum creatinine and cystatin C levels, and incident diabetes mellitus was assessed through follow-up surveys. Cox proportional hazards regression models were used to analyze the association between sarcopenia index and incident diabetes mellitus, adjusting for potential confounders, with hazard ratio (HR) with 95% confidence interval (95% CI) reported.

RESULTS

During a mean follow-up period of 5.0 years, a total of 501 new cases of diabetes were recorded. A total of 7718 participants were included in the analysis. The median age was 60 years, and 46.2% were male. During a mean follow-up period of 5.0 years, 501 cases of incident diabetes mellitus were identified. After adjusting for covariates, Compared with participants in the lowest quartile, the corresponding diabetes HRs (95% CIs) for participants in the second, third, and fourth quartiles were 0.930 (95% CI 0.724-1.193; P = 0.567); 0.892 (95% CI 0.685-1.162; P = 0.398), 0.869 (95% CI 0.657-1.150; P = 0.327). Restricted cubic spline curves revealed that incident rate decreased with increase in sarcopenia index.

CONCLUSIONS

This study provides national longitudinal evidence in China on the association of sarcopenia index, based on serum creatinine and cystatin C levels, with incident diabetes mellitus in middle-aged and older adults. Our findings suggest that sarcopenia index may be a useful biomarker for predicting the risk of diabetes mellitus in this population.

A study of trends in body morphology, overweight, and obesity in Chinese adults aged 40-59 years

OBJECTIVE

To reveal the changing pattern of anthropometry of middle-aged adults aged 40-59 in China from 2000-2020, and to predict the development trend in the next decade, to provide a reference basis for curbing the prevalence of overweight and obesity in them.

METHODS

A grey GM(1,1) prediction model was established for the cross-sectional data on anthropometric measures of 422,851 adults obtained from five series of national physical fitness surveillance in China.

RESULTS

1) From 2000 to 2020, all anthropometric indicators of middle-aged people aged 40-59 years in China maintained growth, with waist circumference increasing at the highest rate, weight at the second highest rate, and height at the slowest rate; 2) Overweight and obesity rates are increasing rapidly, with an average annual increase of 0.37 percentage points and 0.30 percentage points, with a greater increase for men than for women.

CONCLUSION

Without stronger interventions, overweight and obesity rates among middle-aged adults are likely to continue to increase in the future, and coordinated efforts are needed to slow down the obesity epidemic and improve the physical health of middle-aged adults.

Decellularized Extracellular Matrix-Derived Hydrogels: a Powerful Class of Biomaterials for Skeletal Muscle Regenerative Engineering Applications

Purpose

The extracellular matrix (ECM) is a complicated milieu consisting of structural and functional molecules secreted by the resident cells that provides an optimal microenvironmental niche for enhanced cell adhesion, growth, differentiation, and tissue formation and maturation. For decades, ECM bio-scaffolds prepared from decellularized tissues have been used to promote skeletal muscle regeneration; however, it was recently discovered that these decellularized ECM (dECM) materials can be further processed into hydrogels, thus expanding the potential applications of dECM materials in skeletal muscle regenerative engineerisng (SMRE). This review article highlights the recent advances in dECM-derived hydrogels toward skeletal muscle regeneration and repair.

Method

We screened articles in PubMed and bibliographic search using a combination of keywords. Relevant and high-cited articles were chosen for inclusion in this narrative review.

Results

Here, we discuss the skeletal muscle ECM's structure, function, and biochemical composition with emphasis on the role of the ECM during skeletal muscle embryogenesis, growth, development, and repair. Furthermore, we review various hydrogels used to promote skeletal muscle regeneration. We also review the current applications of dECM-derived hydrogels toward SMRE. Finally, we discuss the clinical translation potential of dECM-derived hydrogels for skeletal muscle regeneration and repair and their potential clinical considerations in the future.

Conclusion

Although much progress has been made in the field of dECM-derived hydrogels toward SMRE, it is still in its nascent stage. We believe improving and standardizing the methods of decellularization, lowering the immunogenicity of dECMs, and carrying out in vivo investigations in large animal models would advance their future clinical applications.

Lay Summary

Researchers have discovered an effective way to turn tissue materials into jelly-like substances known as extracellular matrix (ECM)-derived hydrogels. These ECM-derived hydrogels can help muscles heal better after serious injuries. They can be injected into gaps or used to guide muscle growth in the lab or body. This review article explains how these ECM-derived hydrogels are made and how they can be used to improve muscle healing. It also discusses their possible use in clinics and what needs to be considered before using them for medical treatments.

FRET-Based Sensor Zebrafish Reveal Muscle Cells Do Not Undergo Apoptosis in Starvation or Natural Aging-Induced Muscle Atrophy

Muscle atrophy occurs during natural aging and under disease conditions. Muscle cell apoptosis is considered one of the main causes of muscle atrophy, while several recent studies argued that muscle cells do not die during muscle atrophy. Here, sensor zebrafish are generated to visualize muscle cell apoptosis and the engulfment of dead muscle cells by macrophages. Using these sensor zebrafish, starvation, and natural aging-induced muscle atrophy models are established. The data showed that the diameters of muscle cells decreased in both models; however, muscle cell apoptosis is not found in the process of muscle atrophy. In starvation-induced muscle atrophy, it also showed that the number of nuclei in muscle cells remained constant, and there is no increase in the number of macrophages in muscle tissues, both of which further confirmed that muscle cells do not die. In both models, transcriptional analysis showed that the apoptosis pathway is down-regulated, and autophagy and protein degradation pathways are up-regulated. All these data indicated that although there is a great reduction of muscle mass during starvation or aging-induced muscle atrophy, muscle cells do not die by apoptosis. These findings provide new insights into muscle atrophy and can benefit the treatments for muscle atrophy-related diseases.

The Roles of myomiRs in the Pathogenesis of Sarcopenia: From Literature to In Silico Analysis

Senile sarcopenia is a condition of age-associated muscular disorder and is a significant health issue around the world. In the current review, we curated the information from the NCBI, PubMed, and Google Scholar literature and explored the non-genetic and genetic causes of senile sarcopenia. Interestingly, the myomiRs such as miR-1, miR-206, miR-133a, miR-133b, miR-208b, and miR-499 are skeletal muscle's critical structural and functional regulators. However, very scattered information is available regarding the roles of myomiRs in different skeletal muscle phenotypes through a diverse list of known target genes. Therefore, these pieces of information must be organized to focus on the conserved target genes and comparable effects of the myomiRs in regulating senile sarcopenia. Hence, in the present review, the roles of pathogenetic factors in regulating senile sarcopenia were highlighted. The literature was further curated for the roles of myomiRs such as hsa-miR-1-3p/206, hsa-miR-27-3p, hsa-miR-146-5p, and hsa-miR-499-5p and their target genes. Additionally, we used different bioinformatics tools and predicted target genes of the myomiRs and found the most critical target genes, shared pathways, and their standard functions in regulating muscle structure and functions. The information gathered in the current review will help the researchers to explore their possible therapeutic potential, especially the use of the myomiRs for the treatment of senile sarcopenia.

Clinical Relevancies of Sarcopenic Obesity in Patients with Metabolic Dysfunction-Associated Fatty Liver Disease (MASLD)

AIM

Sarcopenic obesity (SO) is associated with adverse outcomes in diseased patients. This study aimed to examine the prevalence and risks associated with SO, with a focus on the impact of SO on cardiovascular risk in patients with MASLD.

MATERIALS AND METHODS

In this cross-sectional study, patients with MASLD were prospectively enrolled. Through dual-energy X-ray absorptiometry (DXA) scans, their body compositions were analyzed to identify who had SO and osteopenia/osteoporosis. The primary aim is to investigate risks associated with SO, followed by analyzing the association between SO and cardiovascular disease (CVD).

RESULTS

Two hundred and twenty-three patients with MASLD were enrolled. The prevalence of SO was 47.1%, respectively. Patients coexisted with MASLD and SO had increased visceral adipose tissue (VAT), higher fatty liver index (FLI) and fibrosis 4 (FIB-4) score. Regression analysis revealed higher FLI and FIB-4 score, as well as history of hypertension, were risks associated with SO. The 10-year atherosclerotic cardiovascular disease (ASCVD) risk score was higher in patients coexisted with MASLD and SO compared to those without (10.1% vs. 7.3%, p = 0.006). Regression analysis showed that increased VAT and FIB-4 score were associated with raised risk of ASCVD.

CONCLUSION

Prevalence of SO in MASLD patients is considerable. The presence of SO also linked to higher risk of ASCVD. Therefore, the recognition of SO in patients with MASLD is important in clinical care.

Prospective associations between muscle strength and genetic susceptibility to type 2 diabetes with incident type 2 diabetes: a UK Biobank study

BACKGROUND

This study explored whether the prospective associations between muscle strength and incident type 2 diabetes (T2D) differ by varying levels of genetic susceptibility to T2D.

METHODS

This study included 141,848 white British individuals from the UK Biobank. Muscle strength was expressed as the relative value of grip strength (measured by a hand dynamometer) divided by fat-free mass (measured via bioelectrical impedance analysis). Three categories of muscle strength (low, medium and high) were generated based on the sex- and age-specific tertiles. Genetic risk of T2D was estimated using a weighted polygenic risk score based on 138 independent single-nucleotide polymorphisms for T2D. During a median 7.4-year follow-up, 4,743 incident T2D cases were accrued. Cox regression with age as the underlying timescale was fit.

RESULTS

High muscle strength was associated with a 44% lower hazard of T2D (HR:0.56, 95%CI:0.52-0.60), compared with low muscle strength, after adjustment for genetic risk of T2D. The inverse association between muscle strength and incident T2D was weaker in individuals with high genetic susceptibility. There was evidence of interaction between muscle strength and genetic susceptibility to T2D (p-additive = 0.010, p-multiplicative = 0.046). The estimated 8-year absolute risk of T2D was lower for high genetic risk-high muscle strength (2.47%), compared with low (2.89%) or medium (4.00%) genetic risk combined with low muscle strength.

CONCLUSIONS

Higher muscle strength was associated with lower relative risk of developing T2D, irrespective of genetic susceptibility to T2D, while such association was weaker in the high genetic risk group. Individuals at high genetic risk of T2D but with high muscle strength may have a lower 8-year absolute risk of developing T2D, compared with those at low or medium genetic risk but with low muscle strength. Our findings inform future clinical trials to prevent or delay the onset of T2D by implementing muscle-strengthening interventions among individuals of varying levels of genetic susceptibility to T2D, including those with high genetic risk.

Adherence to a healthy dietary pattern mitigates the detrimental associations between osteosarcopenic adiposity and both all-cause mortality and life expectancy: a cohort study

Background and aims: To determine the associations between osteosarcopenic adiposity (OSA) and both all-cause mortality and life expectancy, and to investigate whether adherence to a healthy diet can modify these associations. Methods: Utilizing data obtained from 201 223 UK Biobank participants, we assessed body composition for OSA and a healthy diet score was used to assess dietary quality. Results: Compared to participants with no body composition abnormality, the adjusted HRs (95% CIs) of all-cause mortality for those with 1, 2, and 3 (OSA) abnormalities were 1.13 (1.08, 1.18), 1.28 (1.21, 1.35), and 2.01 (1.58, 2.56) after adjustments, respectively. Compared with participants with no body composition abnormality, OSA patients with poor dietary patterns had a higher risk of all-cause mortality (HR = 2.92, 95% CI: 1.96, 4.36) than those with medium (HR = 1.73, 95% CI: 1.27, 2.37) and healthy dietary patterns (HR = 1.39, 95% CI: 0.34, 5.60). Specifically, a lower intake of fish and a higher intake of processed meat contributed to such different associations. Compared with participants without body composition abnormality, those with 1, 2, and 3 (OSA) body composition abnormalities had 0.31 (95% CI: -0.07, 0.69), 0.62 (95% CI: 0.16, 1.09) and 3.03 (95% CI: 1.05, 5.00) years of reduced life expectancy at age 45 years. Conclusions: Body composition abnormality, particularly OSA, is associated with both increased risk of all-cause mortality and reduced life expectancy. Nevertheless, it is noteworthy that adopting a healthy dietary pattern appears to mitigate these associations.

Relationship of monocyte to high-density lipoprotein ratio (MHR) and other inflammatory biomarkers with sarcopenia: a population-based study

OBJECTIVES

In previous studies, several inflammatory biomarkers derived from complete blood cell counts (CBC), such as systemic immune inflammation index (SII), neutrophil-to-lymphocyte ratio (NLR), and non‑high‑density lipoprotein cholesterol to high‑density lipoprotein cholesterol ratio (NHHR) have been identified as predictors of sarcopenia. However, whether Monocyte to High-Density Lipoprotein Cholesterol Ratio (MHR) can predict the development of sarcopenia has not yet been established. The research first attempts to investigate the association between MHR and low muscle mass and to compare the predictive abilities of MHR, SII, NLR, and NHHR for low muscle mass risk.

METHODS

The study comprised 10,321 participants aged 20 years and above from the United States. Multiple logistic regression was performed to explore the association between ln-transformed MHR, SII, NLR, NHHR and low muscle mass. Additionally, AUC values and ROC curves were used to assess the predictive effectiveness of ln MHR and other markers (ln SII, ln NLR, ln NHHR, ln MHR + ln SII, ln MHR + ln NHHR, and ln MHR + ln NLR). The bootstrap estimated 95% Cl was shown with the AUC.

RESULTS

In the fully adjusted model, ln SII, ln NLR, ln NHHR, ln MHR, ln MHR + ln SII, ln MHR + ln NHHR, and ln MHR + ln NLR were positively associated with low muscle mass (ln SII: OR = 1.59 [1.37-1.84]; ln NLR: OR = 1.35 [1.13-1.60]; ln NHHR: OR = 1.49[1.27-1.75]; ln MHR: OR = 1.98 [1.68-2.33]; ln MHR + ln SII: OR = 1.61 [1.46-1.79]; ln MHR + ln NHHR: OR = 1.42 [1.29-1.56]; ln MHR + ln NLR: OR = 1.58 [1.41-1.78]). Compared to the lowest quartile of ln MHR, higher quartiles were significantly associated with increased odds of low muscle mass (P for trend < 0.0001). In ROC analysis, ln MHR + ln SII had a higher AUC value than other indicators (AUC = 0.608).

CONCLUSION

Ln-transformed MHR, SII, NLR, and NHHR were positively associated with low muscle mass. MHR outperforms SII, NLR, and NHHR in predicting sarcopenia.

Muscle Dysfunction and Physical Recovery After Critical Illness

During critical illness, patients experience significant and rapid onsets of muscle wasting and dysfunction with loss of strength, mass, and power. These deficits often persist long after the ICU, leading to impairments in physical function including reduced exercise capacity and increased frailty and disability. While there are numerous studies describing the epidemiology of impaired muscle and physical function in the ICU, there are significantly fewer data investigating mechanisms of prolonged and persistent impairments in ICU survivors. Additionally, while several potential clinical risk factors associated with poor physical recovery have been identified, there remains a dearth of interventions that have effectively improved outcomes long-term among survivors. In this article, we aim to provide a thorough, evidence-based review of the current state of knowledge regarding muscle dysfunction and physical function after critical illness with a focus on post-ICU and post-hospitalization phase of recovery.

Association Between Relative Grip Strength, Insulin Resistance, and Nonalcoholic Fatty Liver Disease Among Middle-Aged and Older Adults: A Prospective Cohort Study

Introduction: This study aims to investigate the combined association between insulin resistance (IR) levels, relative grip strength (RGS), and the incidence of nonalcoholic fatty liver disease (NAFLD), stratified by sex, using longitudinal data. Methods: The study included 1702 adult participants aged 51-88 years who completed surveys in both 2013-2014 and during a subsequent follow-up in 2019-2020. NAFLD was assessed using the hepatic steatosis index, and RGS was measured using the JAMA-5030J1 equipment (SAEHAN, Korea). To assess the interaction between RGS and IR levels and their impact on NAFLD risk, we employed a proportional hazards Cox regression model. Hazard ratios (HR) and 95% confidence intervals (95% CI) were calculated for NAFLD incidence. Results: After adjusting for various confounding variables, we observed a significant decrease in NAFLD risk in the middle RGS group (HR = 0.70, 95% CI = 0.53-0.93) and high RGS group (HR = 0.31, 95% CI = 0.22-0.44) compared to the low RGS group. In addition, significant sex differences were noted in the relationship between IR, RGS levels, and NAFLD incidence across different groups. Conclusions: This study highlights that higher RGS levels are independently associated with a reduced risk of developing NAFLD. Notably, RGS emerges as a predictive indicator for assessing NAFLD risk.

Cross-sectional and longitudinal associations between glycaemic measures and grip strength in people without diabetes in the UK Biobank cohort study

PURPOSE

To investigate associations between glycaemic measures (HbA1c, random glucose), and grip strength (GS) in adults without prevalent diabetes.

METHODS

We included 381,715 UK Biobank participants aged 38-73 years without diabetes (any type) with complete baseline measures for GS and HbA1c (main analyses), and glucose (supplementary analyses). Cross-sectional sex- and age-stratified associations between each glycaemic measure, GS, and probable sarcopenia (low GS) were examined with regression analyses. Changes in GS over 8.9 years were classified into four groups (decline, stable low, stable high, or reference (increase or maintained within the normal range)) in 36,228 participants and associations with baseline glycaemic measures explored using multinomial regression.

RESULTS

Higher HbA1c (mmol/mol) was associated with weaker mean GS (kg) (regression coefficient and 95% confidence intervals (CI): - 0.08 (- 0.09, - 0.07)), and increased odds of probable sarcopenia (odds ratio (OR) and 95% CIs: 1.02 (95% CI: 1.01, 1.02)) in males and across the age groups. In females, higher HbA1c was associated with weaker mean GS only in mid-life (e.g., 50-59 years: - 0.06 (- 0.07, - 0.05)). In males, but not in females with repeated GS, higher HbA1c was associated with decreased odds of stable high (0.97 (0.96, 0.99) and increased odds of stable low (1.03 (1.01, 1.04)) GS pattern (0.98 (0.97, 0.980)) over the follow-up. The results for glucose in supplementary analyses were mixed, especially in females.

CONCLUSIONS

The associations between HbA1c and GS in people without diabetes warrant replication and consideration of the effect on muscle strength when interventions to promote normoglycaemia are trialled.

Medical Nutrition Therapy and Physical Exercise for Acute and Chronic Hyperglycemic Patients with Sarcopenia

A wide range of factors contribute to the overlap of hyperglycemia-acute or chronic-and sarcopenia, as well as their associated adverse consequences, which can lead to impaired physical function, reduced quality of life, and increased mortality risk. These factors include malnutrition (both overnutrition and undernutrition) and low levels of physical activity. Hyperglycemia and sarcopenia are interconnected through a vicious cycle of events that mutually reinforce and worsen each other. To explore this association, our review compiles evidence on: (i) the impact of hyperglycemia on motor and muscle function, with a focus on the mechanisms underlying biochemical changes in the muscles of individuals with or at risk of diabetes and sarcopenia; (ii) the importance of the clinical assessment and control of sarcopenia under hyperglycemic conditions; and (iii) the potential benefits of medical nutrition therapy and increased physical activity as muscle-targeted treatments for this population. Based on the reviewed evidence, we conclude that a regular intake of key functional nutrients, together with structured and supervised resistance and/or aerobic physical activity, can help maintain euglycemia and improve muscle status in all patients with hyperglycemia and sarcopenia.

Enhancement of Lower Limb Muscle Strength and Reduction of Inflammation in the Elderly: A Randomized, Double-Blind Clinical Trial Comparing Lacticaseibacillus paracasei PS23 Probiotic with Heat-Treated Supplementation

Background: As individuals age, there is a gradual loss of muscle mass and strength, which not only impairs physical functionality but also heightens the risk of falls and diminishes independence among older adults. Probiotics have emerged as a focus of recent research due to their potential role in enhancing muscle health via the gut-muscle axis. This study evaluates the effects of live and heat-treated Lacticaseibacillus paracasei PS23 (PS23) supplementation on muscle strength and mass in the elderly. Methods: This study recruited 119 participants, aged 65-85 years, and randomly assigned them to receive a placebo (0 × 1010 CFU/day), L-PS23 (live PS23, 2 × 1010 CFU/day), or HT-PS23 (heat-treated PS23, 2 × 1010 cells/day) for a duration of 12 weeks. Assessments of blood pressure, body composition, muscle strength, functional physical fitness, and biochemical parameters were conducted at baseline, 6 weeks, and 12 weeks. Results: Among the 100 subjects who completed the trial, supplementation with both L-PS23 and HT-PS23 significantly enhanced lower limb muscle strength and endurance compared to the placebo (p < 0.05), although no significant differences were observed in muscle mass or upper limb muscle strength across the groups. Additionally, while most muscle anabolism-related markers showed no significant changes, both supplements effectively decreased inflammatory markers related to aging-C-reactive protein (CRP: L-PS23, p = 0.016; HT-PS23, p = 0.013) and interleukin-6 (IL-6: L-PS23, p = 0.003; HT-PS23, p < 0.001)-and increased interleukin-10 levels (L-PS23, p = 0.014; HT-PS23, p = 0.005). Notably, only the HT-PS23 group demonstrated a significant increase in testosterone levels (p = 0.029). Conclusions: 12 weeks of supplementation with L-PS23 and HT-PS23 improved lower limb muscle strength and endurance but did not significantly enhance muscle mass in older adults. Both supplements also proved effective in reducing inflammatory markers and elevating testosterone levels. HT-PS23, administered as a heat-treated probiotic, provided more pronounced benefits to the elderly compared with its probiotic counterpart, L-PS23.

Long-term burden of body mass index since childhood and impaired physical performance in midlife

BACKGROUND

The impact of long-term burden of body mass index (BMI) since childhood on physical performance in midlife remains unclear. We aimed to investigate the association between cumulative exposure to BMI since childhood and midlife physical performance by using data from the Bogalusa Heart Study (BHS).

METHODS

This longitudinal study consisted of 749 participants (aged 37.6 to 56.7 years at follow-up) who had been examined at least four times during childhood, with 39.3 years of follow-up.

RESULTS

BMI in childhood, adulthood, as a cumulative burden of BMI in childhood, or as a cumulative burden from childhood to adulthood were inversely associated with midlife Short Physical Performance Battery (SPPB) scores, 4-m gait speed, and 6-min walking distance. Individuals with higher BMI as adults but not as children did not have lower SPPB scores (OR,1.67; 95% CI, 0.85-3.27), while individuals with consistently high BMI from childhood to adulthood (2.13 1.18-3.82) and individuals with high childhood BMI (2.12 [1.10-4.10]) but low adult BMI had significantly increased risk compared with individuals with low child and low adult BMI.

CONCLUSION

Cumulative burden of BMI from childhood to midlife associated with worse midlife physical performance. Maintaining a healthy body weight throughout life may play a role in preventing or delaying the onset of functional decline.

IMPACT

We examined the impact of long-term burden of body mass index (BMI) since childhood on subsequent physical performance in midlife. We found that ①BMI in childhood and cumulative burden of BMI since childhood were associated with poor physical function in midlife; ② Individuals with high childhood BMI but low adult BMI have poor midlife physical performance; ③ Subjects with both high childhood and adulthood BMI have worse midlife physical performance. Our findings have important implications for active monitoring BMI from childhood and turning the focus of functional decline prevention to primary and primordial prevention.

Association between sarcopenia and weight-adjusted waist index in male patients with type 2 diabetes

BACKGROUND

The Weight-adjusted-waist index (WWI) has emerged as a predictive factor for a range of metabolic disorders. To date, the predictive value of the WWI in relation to sarcopenia in individuals with diabetics has not been extensively explored. This study aims to investigate the impact of the WWI on the prevalence of sarcopenia among patients with type 2 diabetes mellitus (T2DM).

METHOD

In this study, we enrolled 417 patients with T2DM from the Second Affiliated Hospital and Yuying Children's Hospital of Wenzhou Medical University between Dec. 2023 and Apr. 2024. The relationship between the WWI and the prevalence of sarcopenia in T2DM patients was evaluated using multivariate logistic regression, subgroup analysis, restricted cubic spline (RCS) analysis, and receiver operating characteristic (ROC) curve analysis.

RESULTS

Among the 417 patients with T2DM, 76 (18.22%) were identified as having sarcopenia. The prevalence of sarcopenia across the WWI quartile categories, from the first to the fourth quartile, was 8.65%, 8.57%, 20.19% and 8.65% respectively. Multivariate logistic regression analysis revealed that, after adjusting for covariates, a higher WWI was an independent risk factor for sarcopenia in male T2DM patients (OR = 1.836, 95% CI: 1.216-2.772, P = 0.004). This association was not observed in female patients. Subgroup analysis further revealed a stronger correlation between WWI and sarcopenia among male patients with higher HbA1c levels. In males, RCS regression demonstrated a non-linear positive correlation, with an inflection point at a WWI of 10.42 cm/√kg. Finally, the area under the ROC curve (AUC) for the WWI was 0.612.

CONCLUSIONS

WWI emerges as a robust and independent risk factor for sarcopenia in male patients with T2DM. WWI may serve as an accessible and cost-effective tool for identify sarcopenia in patients with diabetes.

The mediating role of body surface area-adjusted basal metabolic rate: effects of low muscle mass and central obesity on cognitive impairment in Chinese patients with type 2 diabetes mellitus

Background

This study investigates the relationship between basal metabolic rate (BMR), body composition, obesity indices, and cognitive impairment (CI) in middle-aged and older type 2 diabetes mellitus (T2DM) patients, assessing their potential role in CI screening.

Methods

A cross-sectional study included 1243 T2DM patients over 45 years old. CI was assessed using the Montreal Cognitive Assessment. BMR and body composition indices were measured through bioelectrical impedance analysis. The associations and predictions related to CI were explored using multivariable-adjusted logistic regression, restricted cubic spline (RCS) models, and receiver operating characteristic (ROC) curve analyses. Mediation analysis explored the role of BMR adjusted by body surface area (BMR/BSA) in CI risk.

Results

Patients with CI showed significantly lower BMR, BMR adjusted for height squared (BMR/Height²), BMR/BSA, appendicular skeletal muscle mass (ASM), and fat-free mass (FFM), alongside higher waist circumference (WC) and percentage of body fat. Logistic regression showed that participants in the fourth quartile of BMR, BMR/Height2, and BMR/BSA had approximately a 54% reduced risk of CI (odds ratio range 0.457 to 0.463). RCS analysis indicated a linear decrease in CI risk with increasing BMR metrics. ROC analysis indicated high predictive efficacy for CI with combined indicators, particularly BMR and FFM (area under the curve 0.645). Mediation analysis suggested that BMR/BSA played a significant mediating role in WC, ASM and FFM on CI risk, with a mediation proportion ranging from 45.73% to 50.87%.

Conclusion

Low energy expenditure assessed by BMR/BSA is an independent risk factor for increased CI risk in middle-aged and elderly T2DM patients. Central obesity, low muscle mass, and low energy expenditure significantly elevate CI risk in this population.

A lower atherogenic index of plasma was associated with a higher incidence of sarcopenia

Sarcopenia is an age-related muscle senescence disease that leads to functional limitations, physical disability and premature death in older adults. Atherogenic index of plasma (AIP) is a novel indicator of atherosclerotic status based on triglycerides and high-density lipoprotein cholesterol. The aim of this study was to investigate the association between AIP and new-onset sarcopenia and its components among middle-aged and older adults in a Chinese community. This cohort study included 7,992 participants who were free of sarcopenia in 2011 in the China Health and Retirement Longitudinal Study and were followed up in 2013 and 2015. Sarcopenia was assessed using the recommendations of the Asian Working Group for Sarcopenia 2019. Longitudinal associations between AIP and sarcopenia and its components were assessed using Cox proportional risk regression modeling. The results showed that AIP was negatively associated with sarcopenia [HR and 95% CI: 0.73 (0.62-0.86)]; with muscle mass [β and 95%CI: 0.49 (0.4-0.57)], skeletal muscle mass index [β and 95%CI: 0.17 (0.15-0.2)], and grip strength [β and 95% CI: 0.17 (0.15-0.2)] being positively correlated. A lower AIP was associated with a lower muscle mass and handgrip strength and higher incidence of sarcopenia. Regular measurement of AIP in the middle-aged and older population in the community can help in the early diagnosis and intervention of sarcopenia.

Association of Skeletal Muscle Mass with Habitual Exercise, Mealtime and Sleep in Middle-Aged Men: Cross-Sectional Study

Objective: To investigate the cross-sectional association between skeletal muscle mass and lifestyles including exercise, mealtime, and sleep habits in adult men aged under 64. Materials and Methods: A total of 101 Japanese men aged under 64 who underwent "Anti-aging Health Checkups" were enrolled in the study. Cross-sectional analyses were conducted using the subjects' data such as body mass index, skeletal muscle mass index (SMI), and self-reported lifestyle information. The physical activity (PA) value of habitual exercise per week (metabolic equivalent hr/week) was categorized into three groups. Mealtime combination of breakfast and dinner time was categorized into five groups. A multiple regression analysis demonstrated how each PA group has an association with SMI. Moreover, an analysis of covariance was performed to investigate the association between "mealtime combined with PA" and SMI levels by comparison and to investigate the association between "sleep duration or satisfaction combined with PA" and SMI levels, respectively. Results: The subjects with "breakfast before 8 a.m." had a significant positive association between SMI and PA levels; in addition, among the subjects from the "dinner before 8 p.m." group, as the PA level was higher, the SMI level increased. Consequently, the SMI level increased as the PA level was higher among the subjects who had "breakfast before 8 a.m. and dinner before 8 p.m." Furthermore, sufficient sleep such as more than 6 hr and satisfied sleep had positive associations with SMI as PA levels increased. Conclusion: These findings suggest a potential benefit of habitual exercise with breakfast before 8 a.m., dinner before 8 p.m., and sufficient sleep for maintaining skeletal muscle mass among middle-aged men.

Inflammation mediates the association between muscle mass and accelerated phenotypic aging: results from the NHANES 2011-2018

Background

Muscle mass plays a pivotal role in health maintenance, yet its connection to biological aging remains underexplored. This study investigates the association between appendicular skeletal muscle mass index (ASMI) and phenotypic age(PhenoAge), while examining the mediating role of systemic inflammation.

Methods

The analysis included 7,440 participants from the NHANES 2011-2018. Phenotypic Age Acceleration (PhenoAgeAccel) was calculated as the residuals from regressing PhenoAge on chronological age. Multivariable linear regression analyses were performed to assess the association between ASMI and PhenoAgeAccel. Mediation analysis was conducted to quantify the extent to which systemic inflammation contributes to this association.

Results

Our analysis revealed that higher ASMI is linked to slower biological aging, as evidenced by lower PhenoAgeAccel (β = -0.48, 95% CI: -0.66 to -0.29, p = 0.0001). Systemic inflammation partially mediated this effect, with a mediation proportion of 35.1%. The association varied notably across demographic and health-related subgroups, being particularly significant in females, individuals with obesity, and those with lower physical activity.

Conclusion

These findings highlight the critical importance of muscle mass in slowing biological aging, with systemic inflammation emerging as a key biological mediator. The public health implications are substantial, suggesting that targeted interventions-such as resistance training, anti-inflammatory diets, and personalized medical approaches-could play a pivotal role in decelerating biological aging and improving long-term health outcomes.

Association of body mass index with disability in activities of daily living in older adults: a systematic review of the literature based on longitudinal data

BACKGROUND

The influence of Body Mass Index (BMI) on the functional capacity for daily activities in older adults is a significant concern. Our study is designed to delineate the longitudinal relationship between BMI and the ability of daily living activities among older adults.

METHODS

Two researchers conducted a comprehensive literature search and independent screening of articles in PubMed, Embase, Web of Science, China National Knowledge Infrastructure (CNKI), the Database for Chinese Technical Periodicals (VIP), and Wanfang, covering the period from January 2000 to May 2024. Studies were selected based on predefined inclusion and exclusion criteria, and relevant data were extracted for subsequent meta-analysis using the Cochrane Collaboration's Review Manager 5.3 software.

RESULTS

After rigorous selection, four longitudinal studies were incorporated into our meta-analysis. The findings indicated that underweight older adults exhibited a higher likelihood of experiencing difficulties with basic activities of daily living (BADL) (odds ratio [OR] = 1.33, 95% confidence interval [CI]: [1.03, 1.72]; P = 0.03). Conversely, overweight older adults were found to have a reduced likelihood of BADL (odds ratio [OR] = 0.81, 95% confidence interval [CI]: [0.79, 0.83]; P < 0.001). However, overweight and obese older adults demonstrated an increased likelihood of challenges with Instrumental Activities of Daily Living (IADL) (odds ratio [OR] = 1.58, 95% confidence interval [CI]: [1.25, 2.00]; P < 0.01).

CONCLUSIONS

Our longitudinal meta-analysis substantiates the correlation between underweight status and the impairment of BADL in older adults, irrespective of gender. It also reveals that overweight older adults have a lower risk of BADL difficulties, yet a higher risk of IADL challenges, which is further exacerbated in obesity. The early identification and management of BMI in this population could be instrumental in preventing a decline in ADL. Recognizing the role of BMI categories in this context is essential for developing targeted preventative strategies for the elderly, while also accounting for other modifiable risk factors such as pain and depression.

Diacylglycerol kinase δ is required for skeletal muscle development and regeneration

Diacylglycerol kinase δ (DGKδ) phosphorylates diacylglycerol to produce phosphatidic acid. Previously, we demonstrated that down-regulation of DGKδ suppresses the myogenic differentiation of C2C12 myoblasts. However, the myogenic roles of DGKδ in vivo remain unclear. In the present study, we generated DGKδ-conditional knockout mice under the control of the myogenic factor 5 (Myf5) gene promoter, which regulates myogenesis and brown adipogenesis. The knockout mice showed a significant body weight reduction and apparent mass decrease in skeletal muscle, including the tibialis anterior (TA) muscle. Moreover, the thickness of a portion of the myofibers was reduced in DGKδ-deficient TA muscles. However, DGKδ deficiency did not substantially affect brown adipogenesis, suggesting that Myf5-driven DGKδ deficiency mainly affects muscle development. Notably, skeletal muscle injury induced by a cardiotoxin highly up-regulated DGKδ protein expression, and the DGKδ deficiency significantly reduced the thickness of myofibers, the expression levels of myogenic differentiation markers such as embryonic myosin heavy chain and myogenin, and the number of newly formed myofibers containing multiple central nuclei during muscle regeneration. DGKδ was strongly expressed in myogenin-positive satellite cells around the injured myofibers and centronucleated myofibers. These results indicate that DGKδ has important roles in muscle regeneration in activated satellite cells. Moreover, the conditional knockout mice fed with a high-fat diet showed increased fat mass and glucose intolerance. Taken together, these results demonstrate that DGKδ plays crucial roles in skeletal muscle development, regeneration, and function.

The prognostic value of pre-treatment sarcopenia in overall survival in head and neck cancer patients: a systematic review

The aim of this study was to determine the prognostic value of pre-treatment sarcopenia, defined radiologically (cervical (C3) or lumbar (L3) region), in adult head and neck cancer (HNC) patients undergoing treatment with curative intent. A systematic search of the PubMed and Scopus databases was performed up to March 2024. Inclusion criteria were adult patients with locally advanced HNC, sarcopenia defined radiologically at the C3 and/or L3 level, and patients receiving primary treatment with curative intent. Risk of bias was assessed using the ROBINS-I tool non-randomised studies. Thirty studies involving a total of 6924 adult patients with HNC were included in this review. Pre-treatment sarcopenia was significantly associated with worse overall survival outcomes in 26 of the 30 studies (87%), across all treatment modalities with curative intent. The most frequent sex-specific SMI cut-off values were <52.4 cm2/m2 for males and <38.5 cm2/m2 for females. The findings of this review suggest that sarcopenia is a strong prognostic factor of overall survival in HNC patients undergoing primary curative treatment. Sarcopenia evaluation appears to be a good prognostic marker in the HNC population. Future nutritional interventional studies might focus on reversing the muscle loss and improving overall outcomes in identified sarcopenic individuals.

Masseter Muscle Volume, Sarcopenia, and Muscle Determinants: Insights from ACTN3 Polymorphism in Elderly Japanese in the Bunkyo Health Study

AIM

Sarcopenia has been with a decrease in masseter muscle (MM) thickness in high-risk older populations. However, the relationship between sarcopenia and determinants of MM volume (MMV) in the general elderly population remains unclear.

METHOD

In a cross-sectional study of 1,484 older adults in Tokyo, we evaluated MMV using 3D MRI scanning, appendicular skeletal muscle mass (ASMM), handgrip strength, dietary intake, smoking, insulin-like growth factor 1 (IGF-1) levels, and the ACTN3 R577X polymorphism. Participants were divided into quintiles based on MMV (Q1-5).

RESULTS

Participants in our study had a mean age of 73.0 ± 5.3 years and their MMV (Men: 35.3 ± 7.8 mL, Women: 25.0 ± 5.1 mL) was significantly higher in men than in women. A significant association between MMV and sarcopenia was observed, with the lowest quintile (Q1) showing a higher risk compared to the highest quintile (Q5) in both sexes. Body mass index (BMI) and age were independent determinants of ASMM in both sexes, whereas BMI, but interestingly not age, was a determinant of MMV. Moreover, IGF-1 was positively correlated with MMV in both sexes; smoking was negatively correlated with MMV in women. The ACTN3 577XX genotype was only associated with smaller MMV in men.

CONCLUSION

Low MMV increased the risk of sarcopenia, particularly in men. BMI and age strongly influenced ASMM, while MMV was only weakly associated with BMI and not with age. Notably, IGF-1 level was positively associated with MMV only, and ACTN3 genotype was associated to reduced MMV only in men.

Noggin Combined With Human Dental Pulp Stem Cells to Promote Skeletal Muscle Regeneration

A proper source of stem cells is key to muscle injury repair. Dental pulp stem cells (DPSCs) are an ideal source for the treatment of muscle injuries due to their high proliferative and differentiation capacities. However, the current myogenic induction efficiency of human DPSCs hinders their use in muscle regeneration due to the unknown induction mechanism. In this study, we treated human DPSCs with Noggin, a secreted antagonist of bone morphogenetic protein (BMP), and discovered that Noggin can effectively promote myotube formation. We also found that Noggin can accelerate the skeletal myogenic differentiation (MyoD) of DPSCs and promote the generation of Pax7+ satellite-like cells. Noggin increased the expression of myogenic markers and the transcriptional and translational abundance of satellite cell (SC) markers in DPSCs. Moreover, BMP4 inhibited Pax7 expression and activated p-Smad1/5/9, while Noggin eliminated BMP4-induced p-Smad1/5/9 in DPSCs. This finding suggests that Noggin antagonizes BMP by downregulating p-Smad and facilitates the MyoD of DPSCs. Then, we implanted Noggin-pretreated DPSCs combined with Matrigel into the mouse tibialis anterior muscle with volumetric muscle loss (VML) and observed a 73% reduction in the size of the defect and a 69% decrease in scar tissue. Noggin-treated DPSCs can benefit the Pax7+ SC pool and promote muscle regeneration. This work reveals that Noggin can enhance the production of satellite-like cells from the MyoD of DPSCs by regulating BMP/Smad signaling, and these satellite-like cell bioconstructs might possess a relatively fast capacity for muscle regeneration.

Associations of Body Mass Index and Percent Body Fat with Osteoporosis, Sarcopenia, and Osteosarcopenia: A Retrospective Study Based on Postmenopausal Women in China

Background/Objectives: Alterations in the body mass index (BMI) and percent body fat (PBF) have been considered to be related to aging-induced changes in bone and muscle. This study aimed to evaluate the associations of the BMI and PBF with osteoporosis, sarcopenia, and osteosarcopenia in postmenopausal women. Methods: A total of 342 participants who underwent musculoskeletal function assessments at the First Affiliated Hospital of Sun Yat-sen University between January 2015 and December 2022 were retrospectively screened. The diagnosis of osteoporosis was based on the WHO criteria, and sarcopenia was diagnosed according to the 2019 consensus of the Asian Working Group for Sarcopenia. Results: The BMI was positively correlated with the musculoskeletal function assessment parameters (bone mineral density, relative skeletal muscle index, and grip strength) and identified as an independent protective factor for sarcopenia alone (OR = 0.592, 95% CI: 0.455-0.769) or osteosarcopenia (OR = 0.411, 95% CI: 0.319-0.529), with a moderate diagnostic accuracy (area under the curve [AUC] = 0.682) for the former and a high diagnostic accuracy (AUC = 0.823) for the latter. However, the PBF was negatively correlated with the relative skeletal muscle index and identified as a risk factor for osteosarcopenia (OR = 1.404, 95% CI: 1.007-1.959), with a moderate diagnostic accuracy (AUC = 0.613). Conclusions: A higher BMI and lower PBF were associated with a lower prevalence of osteosarcopenia in postmenopausal women. Further research is required to elucidate the independent effects of the BMI and PBF on bone health.

The dietary inflammatory index is positively associated with low muscle mass in adults: an analysis of NHANES

INTRODUCTION

Using the data taken from the National Health and Nutrition Examination Survey (NHANES) database, we explored the relationship between the dietary inflammatory index (DII) and low muscle mass (LMM) in adults.

METHODS

We examined 20,424 adults ≥ 20 years old from the 1999-2006 and 2011-2018 NHANES. We hypothesized that the DII is positively associated with the risk of LMM in adults. Regression, subgroup, and restricted cubic spline (RCS) analyses were used to determine the association between the DII and the risk of LMM.

RESULTS

Analyzing the DII as a continuous variable revealed that each unit increase in DII was associated with an 11% increase in the risk of LMM. When categorized by quartile grouping, the analysis indicated that individuals in the highest DII quartile exhibited a 1.78-fold higher risk of LMM compared to those in the lowest quartile (OR = 1.78, 95% CI: 1.45-2.18). The RCS analysis demonstrated that the risk of LMM remained stable for DII below 1.77, but increased sharply for DII of 1.77 or higher. Subgroup analysis further revealed that the impact of DII on LMM risk was more pronounced in individuals with a body mass index (BMI) of 25 kg/m2 or greater.

CONCLUSION

It is necessary to adjust the diet according to the DII to reduce the possibility of LMM and to prevent the occurrence of sarcopenia.

Influence of an inspiratory muscle fatigue protocol on older adults on respiratory muscle strength, muscle oxygen saturation, and functional capacity: a randomized controlled trial

BACKGROUND

The fatigue of the inspiratory musculature, particularly the diaphragm, has been demonstrated to exert systemic effects on the body, impacting cardiovascular and performance outcomes. This study aimed to evaluate the influence of an inspiratory muscle fatigue protocol on respiratory muscle strength, functionality, and muscle oxygen saturation in older adults.

METHODS

A single-blinded randomized controlled clinical trial was conducted on twenty-four older adults aged over 60 years, who met inclusion criteria were physically independent in terms of gait and functionality. Participants were randomly assigned to one of three groups: control group, inspiratory muscle fatigue group, or activation group. Diaphragmatic ultrasonography (diaphragmatic thickness, thickening fraction, diaphragm movement curve), maximal inspiratory mouth pressure, muscle oxygen saturation, and functionality (timed up and go test, for five times sit to stand test) were used to measure the study variables at two time points: pre-intervention (T1) and post-intervention (T2).

RESULTS

In the maximum inspiratory pressure variable in the activation group an increase was found between baseline and post-treatment of 3.00 ± 0.93 cmH2O (P < 0.01), while in the inspiratory muscle fatigue a decrease of -6.75 ± 2.66 cmH2O (P < 0.01) was found. In addition, the inspiratory muscle fatigue group showed lower scores for respiratory and functional variables after performing the diaphragmatic fatigue intervention than the activation and control group (P < 0.05), on the other hand, the activation group showed more positive values for functional and respiratory capacity variables after performing the inspiratory muscle activation training (P < 0.05).

CONCLUSIONS

Fatigue of the inspiratory musculature appears to negatively impact inspiratory muscle strength, peripheral muscle strength, muscular oxygenation, and functionality in older adults. Activation of the inspiratory musculature could contribute to improved respiratory muscle strength and function in these individuals.

TRIAL REGISTRATION

ClinicalTrials.gov ID: NCT06266013.

Effects of Supplemental Vitamin D3, Omega-3 Fatty Acids on Physical Performance Measures in the VITamin D and OmegA-3 TriaL

CONTEXT

Declining muscle strength and performance in older adults are associated with falls, fractures, and premature death.

OBJECTIVE

This work aimed to determine whether supplementation with vitamin D3 or omega-3 fatty acids vs placebo for 2 years improves physical performance measures.

METHODS

VITamin D and OmegA-3 TriaL (VITAL) was a double-blinded, placebo-controlled randomized trial of supplemental vitamin D3 and/or omega-3 fatty acids vs placebo in the prevention of cancer and cardiovascular disease in 25 871 US adults. This ancillary study was completed in a New England subcohort that had in-person evaluations at baseline and 2-year follow-up. This study was conducted with 1054 participants (age: men ≥50 and women ≥55 years) at the Center for Clinical Investigations in Boston. Interventions included a 2 × 2 factorial design of supplemental vitamin D3 (cholecalciferol, 2000 IU/day) and/or marine omega-3 fatty acids (1 g/day). Main outcome measures included 2-year changes in physical performance measures of grip strength, walking speed, standing balance, repeated chair stands, and Timed-up and Go (TUG).

RESULTS

At 2 years, all randomized groups showed worsening walking speeds and TUG. There were no differences in changes in grip strength, walking speeds, Short Physical Performance Battery (composite of walking speed, balance, and chair stands), and TUG between the vitamin D3-treated and the placebo-treated groups and between the omega-3-treated and the placebo-treated groups. Effects overall did not vary by sex, age, body mass index, or baseline measures of total or free 25-hydroxyvitamin D (25[OH]D) or plasma omega-3 index; TUG slightly worsened with vitamin D supplementation, compared to placebo, in participants with baseline total 25(OH)D levels above the median (P = .01; P for interaction = .04).

CONCLUSION

Neither supplemental vitamin D3 nor marine omega-3 fatty acids for 2 years improved physical performance in this generally healthy adult population.

Computational and digital analyses in the INSPIRE mouse cohort to define sex-specific functional determinants of biological aging

Biological age, which reflects the physiological state of an individual, offers a better predictive value than chronological age for age-related diseases and mortality. Nonetheless, determining accurate functional features of biological age remains challenging due to the multifactorial nature of aging. Here, we established a unique mouse cohort comprising 1576 male and female outbred SWISS mice subjected or not to high-fat, high-sucrose diet to investigate multiorgan/system biological aging throughout adulthood. Comprehensive functional and biological phenotyping at ages of 6, 12, 18, and 24 months revealed notable sex-specific disparities in longitudinal locomotion patterns and multifunctional aging parameters. Topological data analysis enabled the identification of functionally similar mouse clusters irrespective of chronological age. Moreover, our study pinpointed critical functional markers of biological aging such as muscle function, anxiety characteristics, urinary patterns, reticulocyte maturation, cardiac remodeling and function, and metabolic alterations, underscoring muscle function as an early indicator of biological age in male mice.

Urinary titin as an early biomarker of skeletal muscle proteolysis and atrophy in various catabolic conditions

Skeletal muscle atrophy impairs quality of life and increases the risk of disease, but current methods for assessment of muscle mass have several limitations. We here investigated the urinary concentration of a fragment of the muscle protein titin as a potential biomarker for the early detection of skeletal muscle atrophy. Four mouse models with different atrophy pathways were studied: those of cardiotoxin-induced acute muscle injury, cast-induced muscle immobilization, lipopolysaccharide-induced sepsis, and streptozotocin-induced diabetes. In all four models, urinary titin levels increased early, concurrent with or preceding upregulation of the atrophy-related genes for atrogin-1 and MuRF-1. The increase in the urinary titin concentration was thus associated with initial muscle damage and the onset of proteolysis, rather than with late-stage muscle wasting. Our findings suggest that urinary titin is a promising biomarker for detection of the onset of skeletal muscle catabolism and prediction of the subsequent development of atrophy in different catabolic states. Noninvasive measurement of urinary titin may therefore allow the earlier detection of skeletal muscle proteolysis compared with conventional techniques.

Defining tibial anterior muscle morphology in first-ever chronic stroke patients using three-dimensional freehand ultrasound

BACKGROUND

Drop foot is common post-stroke, elevating fall risks and mobility limitations. It is caused by weakness and lack of control of the tibialis anterior muscle (TA), for which various rehabilitation treatments are used. A reliable objective estimate of changes in TA muscle morphology and composition can enhance treatment optimization.

OBJECTIVES

We aimed to ascertain 3D freehand ultrasound (3DfUS) reliability in measuring TA muscle volume, length, and echo intensity in stroke patients and healthy controls and its validity by comparing these features across legs, between patients and controls, and between clinical subgroups (i.e. patients with and without ankle contracture, spastic muscle overactivity, and foot dorsiflexor paresis).

METHODS

We included 9 stroke patients and 9 healthy controls to define reliability and 26 stroke patients and 28 healthy controls to define validity. For reliability, data were collected and processed by 2 different operators and processors. For inter- and intra-rater reliability, intra-class correlation coefficient (ICC) and standard error of measurement (SEM) were used. For validity, Wilcoxon-Signed-Ranked and Mann-Whitney U tests were used for comparisons between groups and subgroups.

RESULTS

All measurements showed good to excellent inter- and intra-rater reliability (ICC: 0.816 to 0.997, SEM: 0.5% to 7.8%). Comparison analyses revealed no differences in muscle features among legs, groups, or subgroups.

CONCLUSION

While the 3DfUS is a reliable method to define TA morphology and composition, its clinical validity needs further investigation into factors influencing muscle property changes across various age groups and post-stroke time points.

MESH TERMS

Stroke; Skeletal muscle morphology; muscle composition; 3D freehand ultrasonography, Anterior Tibial Muscle.

Association between handgrip strength and metabolic syndrome in relation to gender and adiposity among middle aged and older Saudi populations

AIM

This cross-sectional study investigated the association between metabolic syndrome (MetS) and handgrip strength (HGS) with respect to sex and adiposity in Saudi men (n = 287) and women (n = 268).

MATERIAL AND METHODS

Anthropometry, body composition, HGS, and blood biochemistry were measured. The average age of the study population was 57.65 ± 9.3 years (men = 55.1 ± 9.3 years, women = 60.4 ± 9.3 years). We report that HGS/body mass index (BMI), HGS/weight, and HGS/fat (%) were significantly higher in controls than in patients with MetS in men but not in women. According to the ROC analysis, relative HGS (RHGS) was higher than HGS alone in the association with MetS, which was significant for men (p < 0.01). At lower quartiles of HGS, the probability of MetS was higher in women, and the same was found in men in the lower quartiles of HGS/%Fat. Multinomial regression revealed significant associations between age and adiposity and MetS in men and HGS in women. Additionally, the linear regression of age, HGS, and weight exhibited significant associations between HGS with WC in both sexes.

CONCLUSION

A higher risk of MetS in the lower quartiles of HGS was found in women, and adiposity moderated the relationship between HGS and MetS in men.