Muscle-to-fat ratio identifies functional impairments and cardiometabolic risk and predicts outcomes: biomarkers of sarcopenic obesity

High muscle-to-fat ratio predicts slow muscle strength decline in middle-aged and older adults: Longitudinal aging study of Taipei

BACKGROUND

Handgrip strength is a vital marker of muscle function and predictor of health outcomes in older adults. This study investigated the relationship between the muscle-to-fat ratio and 3-year decrease in handgrip strength in community-dwelling adults aged ≥50 years.

METHODS

Data were obtained from the Longitudinal Aging Study of Taipei (LAST), a cohort study of adults aged 50 years and older. Measurements from two waves, 3 years apart, were analyzed. Demographics, laboratory data, and handgrip strength data were collected. Appendicular skeletal muscle mass was assessed using bioimpedance analysis, and the relative appendicular skeletal muscle mass index was calculated by dividing appendicular muscle mass by height squared. The muscle-to-fat ratio was derived by dividing appendicular muscle mass by total body fat. Handgrip strength decrease was divided into quartiles; slow decliners experienced the smallest decrease, whereas rapid decliners had the greatest decrease. Associations between the muscle-to-fat ratio and other risk factors were analyzed.

RESULTS

Over 3 years, the Charlson Comorbidity Index, medication use, waist-to-hip ratio, and fat percentage increased, whereas skeletal muscle mass, the muscle-to-fat ratio, and handgrip strength decreased. Rapid decliners were less likely to be male (21.6% vs 33.3%, p = 0.008) or alcohol drinkers (53.8% vs 66.2%, p = 0.01) and had lower skeletal muscle mass (6.3 ± 0.9 vs 6.6 ± 1.0, p = 0.006) and muscle-to-fat ratios (1.0 ± 0.4 vs 1.1 ± 0.5, p = 0.004) but greater fat percentages (30.4 ± 6.6 vs 29.0 ± 7.6, p = 0.045). A greater muscle-to-fat ratio (odds ratio [OR] = 3.751, p = 0.047), greater physical activity (OR = 1.694, p = 0.04), and lower glycated hemoglobin (HbA1c; OR = 0.61, p = 0.008) reduced the risk of rapid decline.

CONCLUSION

The muscle-to-fat ratio, together with physical activity and glycemic control, predicts a decrease in handgrip strength, highlighting its potential as a biomarker of intrinsic capacity and muscle-fat interplay. Further research is needed to explore the underlying biological mechanisms involved.

Association of Appendicular Skeletal Muscle Mass Index and Insulin Resistance With Mortality in Multi-Nationwide Cohorts

BACKGROUND

Although sarcopenia and insulin resistance are closely related, there is limited evidence regarding how they interact to influence mortality across different population groups. The purpose of this study was to examine the relationship between skeletal muscle mass and insulin resistance and its impact on mortality and cardiovascular disease risk using large-scale national data from Korea and the United States.

METHODS

We analysed data from the National Health and Nutrition Examination Survey (NHANES) 1999-2006 and 2011-2018 and the Korea National Health and Nutrition Examination Survey (KNHANES) 2008-2011, with mortality follow-up through to 2019. Cox regression models were used to assess the effects of muscle mass (appendicular skeletal mass index, ASMI) and insulin resistance on all-cause and major adverse cardiovascular and cerebrovascular events (MACCE)-related mortality. Mediation analysis was performed to examine direct and indirect effects.

RESULTS

The study included 8036 participants from NHANES and 14 449 from KNHANES. The sarcopenia group demonstrated a lower homeostasis model assessment for insulin resistance and better metabolic indices than the normal group despite having a higher mortality rate. Insulin resistance positively correlated with muscle mass (r = 0.203, p < 0.001 in the NHANES; r = 0.143, p < 0.001 in the KNHANES), and both insulin resistance and sarcopenia were identified as independent risk factors for all-cause and MACCE-related mortality. When the participants were categorized into four groups based on the presence or absence of insulin resistance and sarcopenia, those with both conditions exhibited the highest risk of all-cause mortality (hazard ratio [HR]: 2.30, 95% confidence interval [CI]: 1.72-3.08 in the NHANES; HR: 2.60, 95% CI: 2.14-3.16 in the KNHANES) and MACCE-related mortality among the groups (HR: 3.18, 95% CI: 1.99-5.08 in the NHANES; HR: 2.47, 95% CI: 1.66-3.69 in the KNHANES). Mediation analysis revealed that low muscle mass was associated with decreased insulin resistance but directly increased both all-cause mortality and MACCE-related mortality (NHANES: total natural direct effects [TNDE], HR: 2.08, 95% CI: 1.57-2.76; KNHANES: TNDE, HR: 1.69, 95% CI: 1.28-2.23).

CONCLUSIONS

This study found that low ASMI was inversely associated with insulin resistance and positively associated with mortality risk in both cohorts. These findings, consistent across two large national studies, highlight the complex relationships between muscle mass, insulin sensitivity and mortality. Further studies are needed to assess the underlying mechanisms and clinical implications of these associations.

TRIAL REGISTRATION

Clinicaltrials.gov ID: NCT05616013.

Sarcopenic obesity and brain health: A critical appraisal of the current evidence

Sarcopenic obesity (SO) is a body composition phenotype derived from the simultaneous presence in the same individual of an increase in fat mass and a decrease in skeletal muscle mass and/or function. Several protocols for the diagnosis of SO have been proposed in the last two decades making prevalence and disease risk estimates of SO heterogeneous and challenging to interpret. Dementia is a complex neurological disorder that significantly impacts patients, carers and healthcare systems. The identification of risk factors for early cognitive impairment and dementia is key to mitigating the forecasted trends of a 2-fold increase in dementia case numbers over the next two decades worldwide. Excess adiposity and sarcopenia have both been independently associated with risk of cognitive impairment and dementia. Whether SO is associated with a greater risk of cognitive impairment and dementia is currently uncertain. This review critically appraises the current evidence on the association between SO with cognitive outcomes and dementia risk. It also discusses some of the putative biological mechanisms that may link the SO phenotype with alteration of brain functions.

The impact of the muscle mass-to-fat ratio on the prognosis of patients undergoing pancreaticoduodenectomy for pancreatic cancer

To evaluate the relationship between the muscle mass-to-fat ratio (MMFR) at the third lumbar spine (L3) and overall survival (OS) as well as related complications after pancreaticoduodenectomy (PD) for pancreatic cancer. Patients who underwent PD for pancreatic cancer between March 2017 and May 2023 at the Second Affiliated Hospital of Soochow University were included. Muscle mass and fat content at the L3 were measured by computed tomography. The specific formula that was used to calculate the MMFR was total abdominal muscle area/(subcutaneous adipose tissue area + visceral adipose tissue area), and the optimal cutoff values of the MMFR based on receiver operating characteristic curves were 0.688 for males and 0.382 for females. Patient characteristics were collected, and multivariate analyses were used to evaluate the impact of the MMFR on prognosis. Kaplan-Meier survival curves and log-rank tests were used to compare OS between the high-MMFR and low-MMFR groups. On the basis of the optimal cutoff values, 191 patients were divided into two groups, with 91 patients in the low-MMFR group and 100 patients in the high-MMFR group. The incidence of POPF was significantly greater in the low-MMFR group than in the high-MMFR group. According to multivariate analysis, the MMFR was an independent factor associated with POPF and OS. Patients with low MMFRs had significantly shorter OS and a greater POPF incidence than did those with high MMFRs. The MMFR is an independent predictor of POPF and affects the OS of patients undergoing PD for pancreatic cancer.

Mapping Normative Muscle Health Metrics Across the Aging Continuum: A Multinational Study Pooling Data From Eight Cohorts in Japan, Malaysia and Taiwan

BACKGROUND

The vigour of our musculature wanes as the years advance, and prognosticating the concomitant trajectories throughout the course of life assumes paramount importance for judicious and timely interventions. In the present study, we aimed to establish age- and sex-specific reference centiles for multiple muscle health metrics and reveal the distributions of these metrics throughout the aging process in the Asian population.

METHODS

By using cross-sectional pooled data of community dwellers aged 20 years or older in eight cohorts from Taiwan, Japan and Malaysia, normative values for muscle health metrics (calf circumference (cm), relative appendicular skeletal muscle (RASM) (kilogram per square metre), body mass index (BMI)-adjusted appendicular skeletal muscle mass (kilogram/(kilogram per square metre)), handgrip strength (kilogram), five-time chair stand (seconds) and gait speed (metre per second)) in men and women, categorized by age groups, are calculated. The mean values, along with the 5th, 25th, 50th, 75th and 95th percentiles of these muscle health metrics, are also delineated for both sexes.

RESULTS

Among 34 265 (16 164 men, 18 101 women) participants from eight cohorts, calf circumference declined in age groups from 60 years onward. RASM values declined from the 50s in men but were stable in women until the 80s. ASM/BMI values showed declines in older age groups for both sexes. Handgrip strength declined similarly from 40 years of age in both sexes. Five-time chair stand performance declined from the 30s. Gait speed peaked at 1.6 m/s in men in their 50s and then declined, while it declined in women in their 60s. The inflection points for decline differed by metric and sex. The 20th percentile cutoffs for individuals aged 65-69 years were as follows: calf circumference, 33.0 cm (men) and 31.5 cm (women); RASM, 7.0 kg/m2 (men) and 5.5 kg/m2 (women); ASM/BMI, 0.78 kg/(kg/m2) (men) and 0.56 kg/(kg/m2) (women); handgrip strength, 30.4 kg (men) and 18.1 kg (women); five-time chair stand, 9.4 s (men) and 10.0 s (women); and gait speed, 0.9 m/s (both). Those in the fifth percentile of all muscle health metrics faced earlier declines than their 95th percentile counterparts did, highlighting the critical roles in identifying these high-risk groups.

CONCLUSION

The pooled analysis of eight Asian cohorts clearly outlined the age-related changes in various muscle health metrics, with the inflection point of accelerated decline showing age- and sex-specific characteristics. Defining trajectories of muscle health metrics across life stages facilitates timely interventions to mitigate age-related risks and promote healthy longevity.

The lean body mass to visceral fat mass ratio is negatively associated with cardiometabolic disorders: a cross-sectional study

The literature has documented conflicting and inconsistent associations between muscle-to-fat ratios and metabolic diseases. Additionally, different adipose tissues can have contrasting effects, with visceral adipose tissue being identified as particularly harmful. This study aimed to explore the relationship between the ratio of the lean mass index (LMI) to the visceral fat mass index (VFMI) and cardiometabolic disorders, including dyslipidemia, hypertension, and diabetes, as previous research on this topic is lacking. This cross-sectional study utilized data from the National Health and Nutrition Examination Survey (NHANES) conducted in the United States and included 10,867 individuals. Logistic regression was employed to explore the association between LMI/VFMI and cardiometabolic disorders. Generalized additive models were utilized to examine the nonlinear relationships between variables. Data analysis revealed a consistent inverse association between ln(LMI/VFMI) and dyslipidemia, hypertension, and diabetes. Each 2.7-fold increase in LMI/VFMI (one unit of ln[LMI/VFMI]) was associated with lower odds ratios (ORs) for these conditions. In men, the ORs were 0.21 (95% CI 0.17-0.25) for dyslipidemia, 0.37 (95% CI 0.30-0.45) for hypertension, and 0.16 (95% CI 0.10-0.23) for diabetes. Similarly, in women, the ORs were 0.22 (95% CI 0.19-0.26), 0.51 (95% CI 0.42-0.61), and 0.19 (95% CI 0.13-0.27). Quartile analysis showed that participants in the highest quartile (Q4) had significantly lower ORs compared to those in the lowest quartile (Q1). In men, Q4 ORs were 0.18 (95% CI 0.14-0.23) for dyslipidemia, 0.30 (95% CI 0.23-0.39) for hypertension, and 0.11 (95% CI 0.06-0.20) for diabetes. In women, Q4 ORs were 0.12 (95% CI 0.10-0.15), 0.39 (95% CI 0.29-0.52), and 0.12 (95% CI 0.06-0.25), respectively. Dyslipidemia and diabetes demonstrated nonlinear patterns, while a linear association was found for hypertension. Subgroup analyses across various characteristics confirmed these findings with no substantial directional changes. Maintaining an appropriate ratio of LMI to VFMI may be associated with favorable metabolic health.

Application value of two-dimensional ultrasound and shear-wave elastography parameters in evaluating sarcopenia with essential hypertension

Background

Patients with essential hypertension have a high risk of muscle mass and strength decline. Ultrasound is a promising method for assessing sarcopenia. This study aimed to analyze the correlation between ultrasound and shear-wave elastography (SWE) features, and muscle mass, muscle strength, and physical performance, and to assess the clinical applicability of ultrasound in the diagnosis of sarcopenia in patients with essential hypertension.

Methods

In total, 134 patients with essential hypertension were enrolled in this cross-sectional study. The appendicular skeletal muscle mass index (ASMI), handgrip strength, and 6-meter walking speed of all the patients were measured. The patients were classified into the sarcopenia group and the non-sarcopenia group. The ultrasound-derived muscle thickness (MT), cross-sectional area (CSA), and SWE of the rectus femoris muscle (RFM) were measured in both the relaxed and contracted states. In addition, ultrasound features, such as the muscle fascicle length (Fl), pennation angle (PA), MT, and SWE of the gastrocnemius medialis muscle (GMM), were measured in the relaxed state. Correlations between the clinical indicators, and the ultrasound and SWE features were analyzed. The clinical indicators, and the ultrasound and SWE features were then compared between the sarcopenia and non-sarcopenia groups to determine the independent predictors. Based on these predictors, diagnostic models were established by logistic regression analysis.

Results

Both the ASMI and grip strength were positively correlated with the ultrasound-derived MT and CSA of the RFM in the relaxed and contracted states, and positively correlated with the MT, Fl, PA, and SWE of the GMM in the relaxed state (all P<0.05). The 6-meter walking speed was positively correlated with the ultrasound-derived MT and CSA of the RFM in the relaxed and contracted states, and positively correlated with the Fl and SWE of the GMM in the relaxed state (all P<0.05). Compared with the non-sarcopenia patients, the sarcopenia patients had a decrease in the ultrasound-derived MT and CSA of the RFM in the relaxed and contracted states, and the MT, Fl and SWE of the GMM in the relaxed state (all P<0.05). Based on these results, the cut-off value of the prediction model was 0.443, and it had a diagnostic sensitivity of 84.5% and a specificity of 90.8%.

Conclusions

Two-dimensional ultrasound combined with the SWE model can be used to diagnose sarcopenia in patients with essential hypertension. The model has high sensitivity and specificity, and can more accurately detect sarcopenia in patients with essential hypertension.

Prevalence of sarcopenic obesity among older adults in communities of China: A multicenter, cross-sectional study

BACKGROUND

This study investigated the prevalence of sarcopenic obesity (SO) among older adults in Chinese communities and its association with chronic diseases.

METHODS

We conducted a post-hoc analysis of a 2014-2015 multicenter cross-sectional study involving adults aged ≥60 years from three representative cities in China. The Asian Working Group for Sarcopenia diagnostic criteria and Chinese local cutoffs were employed to define SO. Data on medical history, lifestyle, quality of life, and cognitive function were collected.

RESULTS

The overall prevalence of SO was 3.58% in men and 2.88% in women among 2821 participants. There was a notable increase in prevalence with age, with rates reaching 6.58% for men and 4.40% for women aged 70-79 years. In the group aged ≥80 years, the prevalence rate increased significantly, reaching 13.16% for men and 18.18% for women. Those with SO had higher body mass index (25.29 ± 1.55 kg/m² vs 24.16 ± 2.48 kg/m²; P < 0.001) and triceps skinfold thickness (21.17 ± 5.93 mm vs 19.34 ± 6.87 mm; P < 0.05) than the normal group. The prevalence of cardiovascular disease (15.38% vs 6.59%; P < 0.01), hypertension (56.04% vs 38.93%; P < 0.01), and stroke (7.69% vs 2.25%; P < 0.01) was also significantly higher in the SO group. Logistic regression showed that those with SO were more likely to have cardiac disease (odds ratio [OR] = 2.20; P = 0.016) and stroke (OR = 2.61; P = 0.039).

CONCLUSION

The prevalence of SO increases with age among the older adult population in China, notably after age 80 years. SO individuals were more likely to have cardiac disease and stroke. It is important to focus on early identification and management strategies.

Impact of fat to muscle ratio with risk of disability on community-dwelling Japanese older adults: A 5-year longitudinal study

PURPOSE

Sarcopenic obesity is a combination of sarcopenia and obesity, which is associated with the onset of disability. Fat to muscle ratio (FMR) is a screening measure that assesses the ratio of muscle mass to fat mass. However, the relationship between the FMR and disability has not been investigated.

METHODS

This study included 11,427 community-dwelling older adults aged ≥65 years enrolled in NCGG-SGS (National Center for Geriatrics and Gerontology-Study of Geriatric Syndromes), a national cohort study in Japan. FMR was measured by the bioelectrical impedance analysis and calculated by dividing fat mass by muscle mass. Cox proportional hazard regression analysis adjusted for covariates was used to investigate the association between FMR and the risk of developing new care needs at 5 years. FMR was divided by about quintile, with quintile 5 as the high.

RESULTS

The high FMR group had the highest incidence of disability at 20.8 % for women and 20.1 % for men. In women, the association between FMR and disability was significantly different for the FMR (hazard risk [HR]: 1.43, 95 % confidence interval [CI]: 1.16-1.75). There was no association between FMR and disability in men (HR: 0.98, 95 %CI: 0.76-1.25). Lagged analyses accounting for reverse causality did not change the relationship.

CONCLUSIONS

FMR is associated with increased risk of disability in women community-dwelling older adults but not among men. Because the rate of decreased muscle strength is faster in men than in women, early decreased muscle strength may affect men's risk of disability more than muscle mass or fat mass.

Low muscle mass-to-fat ratio is an independent factor that predicts worse overall survival and complications in patients with colon cancer: a retrospective single-center cohort study

PURPOSE

This study was performed to investigate influencing factors of preoperative muscle mass-to-fat ratio (MMFR) and its impact on overall survival and postoperative complications of colon cancer.

METHODS

Patients who underwent colectomy for stage I-III colon cancer at the Second Affiliated Hospital of Soochow University between January 2016 and December 2022 were included. The skeletal muscle and fat area at the third lumbar vertebra were measured with preoperative CT measurement. MMFR was defined as the ratio of skeletal muscle area to total fat area, and low MMFR was defined as the 2 lowest tertiles (≤0.585). Univariate and multivariable analyses were conducted to assess the impact of MMFR on overall complications and survival outcomes. Kaplan-Meier survival curves and log-rank test were used to compare the overall survival between high MMFR and low MMFR groups.

RESULTS

A total of 885 patients were analyzed. Female sex, older age, high body mass index, sarcopenia, and high cancer stage were more likely to result in low MMFR. Complications, including intestinal fistula, chylous fistula and organ space surgical site infection were significantly higher in the low MMFR group. Low MMFR was an independent factor associated with overall complications (odds ratio, 1.940; 95% confidence interval [CI], 1.252-3.007; P < 0.01) and long-term survival (hazard ratio, 2.222; 95% CI, 1.443-3.425; P < 0.01). Furthermore, patients with high MMFR had a higher survival rate than patients with low MMFR (P < 0.01).

CONCLUSION

Low MMFR is an independent factor that predicts worse overall survival and complications in patients with colon cancer.

Nutrition and exercise: Cornerstones of health with emphasis on obesity and type 2 diabetes management-A narrative review

While a broad consensus exists that integrated nutrition and regular exercise are foundational for health maintenance and serve as a robust non-pharmacological strategy against cardiometabolic diseases, the nuanced interplay between these elements remains incompletely understood. Through multifaceted interactions, these factors profoundly influence primary metabolic organs, notably the skeletal muscle and adipose tissue. Despite the critical nature of this interactivity, a holistic understanding of the combined effects of physical activity and dietary practices is still emerging. This narrative review aims to elucidate the intertwined roles of nutrition and exercise. It provides a comprehensive overview of their synergistic dynamics and emphasizes the importance of a dual-focus approach in mitigating and managing cardiometabolic disorders, predominantly obesity and type 2 diabetes.

Body Composition, Sarcopenic Obesity, and Cognitive Function in Older Adults: Findings From the National Health and Nutrition Examination Survey (NHANES) 1999-2002 and 2011-2014

OBJECTIVE

Sarcopenic-obesity (SO) is characterized by the concomitant presence of low muscle mass and high adiposity. This study explores the association of body composition and SO phenotypes with cognitive function in older adults.

METHODS

Cross-sectional data in older adults (≥60 years) from NHANES 1999-2002 and 2011-2014 were used. In the 1999-2002 cohort, phenotypes were derived from body mass index (BMI) and dual-X-ray-absorptiometry, and cognition was assessed the by Digit-Symbol-Substitution-Test (DSST). In the 2011-2014 cohort, phenotypes were derived from BMI, waist-circumference (WC), and hand-grip-strength (HGS). Cognition was assessed using four tests: DSST, Animal Fluency, the Consortium-to-Establish-a-Registry-for-Alzheimer's-Disease-Delayed-Recall, and Word Learning. Mediation analysis was conducted to evaluate the contribution of inflammation (C-reactive-protein, CRP) and insulin resistance (Homeostatic-Model-Assessment-for-Insulin-Resistance, HOMA-IR) to the association between body composition and cognitive outcomes.

RESULTS

The SO phenotype had the lowest DSST mean scores (p < 0.05) and was associated with a significant risk of cognitive impairment [Odds Ratio (OR) = 1.9; 95%CI 1.0-3.7, p = 0.027] in the 1999-2002 cohort. A higher ratio of fat mass and fat free mass (FM/FFM) also showed a greater risk of cognitive impairment (OR = 2.0; 95%CI 1.3-3.1, p = 0.004). In the 2011-2014 cohort, the high WC-Low HGS group showed significantly lower scores on all four cognitive tests (p < 0.05) and a higher risk of cognitive impairment. CRP and HOMA-IR were significant partial mediators of the association between FM/FFM and DSST in the 1999-2002 cohort.

CONCLUSIONS

The SO phenotype was associated with a higher risk of cognitive impairment in older adults. Insulin resistance and inflammation may represent key mechanisms linking SO to the development of cognitive impairment.

Association between muscle strength and cardiometabolic multimorbidity risk among middle-aged and older Chinese adults: a nationwide longitudinal cohort study

BACKGROUND

Cardiometabolic multimorbidity (CM) is emerging as a global health challenge. This study investigated the potential impact of muscle strength on the risk of CM in middle-aged and older Chinese adults.

METHODS

In total, 7610 participants were identified from the China Health and Retirement Longitudinal Study (CHARLS). Muscle strength was measured by absolute, relative grip strength (normalized for body mass index) and chair-rising time which were classified into three categories according to tertiles stratified by gender. Cox proportional hazards models were adopted to evaluate the effect of muscle strength on CM.

RESULTS

During follow-up, 235(3.76%) participants from none cardiometabolic diseases (CMD), 140 (19.23%) from diabetes, 119 (21.17%) from heart disease, and 22 (30.56%) from stroke progressed to CM. In participants who had low relative grip strength, CM was more likely to occur in individuals with heart disease at baseline (HR: 1.89, 95%CIs: 1.10 to 3.23). Those with high chair-rising time had a higher risk of CM than those with low chair-rising time in the individuals with diabetes (HR: 1.85, 95%CIs:1.20 to 2.86) and with heart disease (HR: 1.67, 95%CIs:1.04 to 2.70). However, we did not observe an association between muscle strength and CM in participants without CMD or with stroke at baseline.

CONCLUSIONS

In Chinese middle-aged and older adults, low relative grip strength was associated with a higher risk of CM in individuals with heart disease, while high chair-rising time was associated with a higher risk of CM in individuals with diabetes or heart disease.

Targeting obesity for therapeutic intervention in heart failure patients

INTRODUCTION

Heart failure with preserved ejection fraction (HFpEF) is a highly heterogeneous syndrome, making it challenging to improve prognosis with pharmacotherapy. Obesity is one of the leading phenotypes of HFpEF, and its prevalence continues to grow worldwide. Consequently, obesity-targeted interventions have attracted attention as a novel treatment strategy for HFpEF.

AREAS COVERED

The authors review the association between the pathogenesis of obesity and HFpEF and the potential for obesity-targeted pharmacotherapeutic strategies in HFpEF, together with the latest evidence. The literature search was conducted in PubMed up to April 2024.

EXPERT OPINION

The STEP HFpEF (Semaglutide Treatment Effect in People with obesity and HFpEF) and SELECT (Semaglutide Effects on Cardiovascular Outcomes in People with Overweight or Obesity) trials recently demonstrated that the glucagon-like peptide 1 analogue, semaglutide, improves various aspects of clinical outcomes in obese HFpEF patients and significantly reduces cardiovascular and heart failure events in non-diabetic obese patients, along with a substantial weight loss. Future clinical trials with other incretin mimetics with more potent weight loss and sub-analyses of the SELECT trial may further emphasize the importance of the obesity phenotype-based approach in the treatment of HFpEF.

The longitudinal association of adipose-to-lean ratio with incident cardiometabolic morbidity: The CARDIA study

AIM

To assess the association of adipose-to-lean ratio (ALR) with incident type 2 diabetes mellitus (T2DM), hypertension, and dyslipidemia in middle adulthood.

METHOD

Black and White Coronary Artery Risk Development in Young Adults participants without T2DM, hypertension, or dyslipidemia in 2005-06 (baseline) were included. Baseline adipose and lean mass were assessed via dual-energy X-ray absorptiometry. ALR was calculated as adipose divided by lean mass and then standardized within sex strata. Single time-point incident morbidity was assessed every five years from baseline through 2016. Cox proportional hazards regression was used to estimate hazard ratios (HR) for morbidity over 10 years per 1-SD increment in ALR adjusted for cardiovascular risk factors.

RESULT

The cumulative incidence of T2DM was 7.9 % (129 events/N = 1643; 16,301 person-years), 26.7 % (485 events/N = 1819; 17,895 person-years) for hypertension, and 49.1 % (435 events/N = 855, 8089 person-years) for dyslipidemia. In the adjusted models, ALR was positively associated with a risk of T2DM (HR [95 % CI]; 1.69 [1.31, 2.19]) and hypertension (1.23 [1.08, 1.40]). There was no significant interaction between ALR and sex for any morbidity.

CONCLUSION

ALR in middle adulthood is associated with incident T2DM and hypertension. The extent to which localized body composition measures might inform morbidity risk merits further investigation.

L-shaped association between lean body mass to visceral fat mass ratio with hyperuricemia: a cross-sectional study

BACKGROUND

Insufficient attention has been given to examining the correlation between body composition and hyperuricemia, leading to inconsistent findings. The primary objective of this research is to explore the association between lean body mass index (LMI), visceral fat mass index (VFMI), and hyperuricemia. A specific emphasis will be placed on assessing the link between the ratio of lean body mass to visceral fat mass (LMI/VFMI) and hyperuricemia.

METHODS

The present study employed a cross-sectional design and involved a total of 9,646 individuals who participated in the National Health and Nutrition Examination Survey (NHANES). To explore the associations among the variables, logistic and linear regressions were employed. Additionally, subgroup analyses and sensitivity analyses were conducted based on various characteristics.

RESULTS

The results showed that LMI was positively associated with hyperuricemia (for Per-SD: OR = 1.88, 95%CI: 1.75, 2.01; for quartiles [Q4:Q1]: OR = 5.37, 95%CI: 4.31, 6.69). Meanwhile, VFMI showed a positive association with hyperuricemia (for Per-SD: OR = 2.02, 95%CI: 1.88, 2.16; for quartiles [Q4:Q1]: OR =8.37, 95%CI: 6.70, 10.47). When considering the effects of In LMI/VFMI, an L-shaped negative association with hyperuricemia was observed (for Per-SD: OR = 0.45, 95%CI: 0.42, 0.49; for quartiles [Q4:Q1]: OR = 0.16, 95%CI: 0.13, 0.20). Subgroup and sensitivity analyses demonstrated the robustness of this association across different subgroups. Additionally, the segmented regression analysis indicated a saturation effect of 5.64 for the In LMI/VFMI with hyperuricemia (OR = 0.20, 95%CI: 0.17, 0.24). For every 2.72-fold increase of In LMI/VFMI, the risk of hyperuricemia was reduced by 80%.

CONCLUSION

The LMI/VFMI ratio is non-linearly associated with serum uric acid. Whether this association is causal needs to be confirmed in further longitudinal studies or Mendelian randomization.

Metabolic-associated fatty liver disease and sarcopenia: A double whammy

The prevalence of metabolic-associated fatty liver disease (MAFLD) has increased substantially in recent years because of the global obesity pandemic. MAFLD, now recognized as the number one cause of chronic liver disease in the world, not only increases liver-related morbidity and mortality among sufferers but also worsens the complications associated with other comorbid conditions such as cardiovascular disease, type 2 diabetes mellitus, obstructive sleep apnoea, lipid disorders and sarcopenia. Understanding the interplay between MAFLD and these comorbidities is important to design optimal therapeutic strategies. Sarcopenia can be either part of the disease process that results in MAFLD (e.g., obesity or adiposity) or a consequence of MAFLD, especially in the advanced stages such as fibrosis and cirrhosis. Sarcopenia can also worsen MAFLD by reducing exercise capacity and by the production of various muscle-related chemical factors. Therefore, it is crucial to thoroughly understand how we deal with these diseases, especially when they coexist. We explore the pathobiological interlinks between MAFLD and sarcopenia in this comprehensive clinical update review article and propose evidence-based therapeutic strategies to enhance patient care.

Sarcopenic obesity does not impair lower limb strength and physical performance in sufficiently active older adults: a cross-sectional study

This study investigated the associations of sarcopenic obesity (SO) with muscle strength and physical performance in sufficiently active older adults. Data from 72 older sarcopenic obese adults classified as sufficiently active were analyzed. Participants were categorized into four groups based on sex and SO status. Muscle strength/physical performance tests were compared using independent sample t-tests. Multiple linear regression and binary logistic regression were performed to examine the associations between SO and muscle strength and physical performance, adjusting for confounding variables. Only handgrip strength showed differences between SO groups, regardless of sex (p < 0.05). SO negatively explained the variability of handgrip strength (p < 0.05). An increase in handgrip strength values was associated with a decrease in the chances of older adults being classified as SO (p < 0.05). The findings suggest that even with SO, sufficiently active older adults did not present a significant reduction in muscle strength in the lower limbs and physical performance.

Donor fat-to-muscle ratio and kidney transplant outcomes: A proposition of metabolic memory

AIMS

The impact of donor abdominal fat-to-muscle ratio (FMR) on kidney transplant (KT) outcomes was assessed. Given the transient nature of the donor's metabolic environment in transplant recipients, this study investigated the capacity of body composition to induce metabolic memory effects.

MATERIALS AND METHODS

KT patients (n = 895) who received allografts from living donors (2003-2013) were included. Donor fat and muscle were quantified using pre-KT abdominal computed tomography scans. Patients were categorised into donor FMR tertiles and followed up for graft outcomes. Additionally, genome-wide DNA methylation analysis was performed on 28 kidney graft samples from KT patients in the low- and high-FMR groups.

RESULTS

Mean recipient age was 42.9 ± 11.4 years and 60.9% were males. Donor FMR averaged 1.67 ± 0.79. Over a median of 120.9 ± 42.5 months, graft failure (n = 127) and death-censored graft failure (n = 109) were more frequent in the higher FMR tertiles. Adjusted hazard ratios for the highest versus lowest FMR tertile were 1.71 (95% CI, 1.06-2.75) for overall graft failure and 1.90 (95% CI, 1.13-3.20) for death-censored graft failure. Genome-wide DNA methylation analysis identified 58 differentially methylated regions (p < 0.05, |Δβ| > 0.2) and 35 genes showed differential methylation between the high- (FMR >1.91) and low-FMR (FMR <1.27) groups.

CONCLUSIONS

Donors with increased fat and reduced muscle composition may negatively impact kidney allograft survival in recipients, possibly through the transmission of epigenetic changes, implying a body-composition-related metabolic memory effect.

Cardiovascular effects of weight loss in old adults with overweight/obesity according to change in skeletal muscle mass

BACKGROUND

Patients with overweight/obesity and type 2 diabetes are encouraged to lose weight, but not all losing weight gain better cardiovascular health, especially old adults. The change in skeletal muscle mass (SMM) could be the key that explains the heterogenous cardiovascular effects of weight loss. This study aims to assess whether the cardiovascular effects of weight loss vary for those gaining skeletal muscle along with weight loss.

METHODS

The old adults with overweight/obesity and type 2 diabetes in the Look AHEAD study having muscle measurement from dual-energy X-ray absorptiometry were included. Based on the weight change (WC) and SMM change (SMMC) between baseline and the 4-year follow-up, participants were allocated into three groups-weight gain (WG) group, weight loss with muscle loss (WL-ML) group and weight loss with muscle gain (WL-MG) group. Cox proportional hazards regression was performed to evaluate the cardiovascular risk of those gaining or losing SMM with weight loss compared with those gaining weight. Among the participants with weight loss, the ratio of SMMC/WC was calculated, and the association of SMMC/WC with primary cardiovascular outcome was assessed.

RESULTS

A total of 491 participants were included in the study with an average age of 64.56 ± 3.81 years old. A total of 47.0% were male and 49.9% were from the intensive lifestyle intervention arm. Based on their WC and SMMC, 43 were assigned to the WG group, 373 to the WL-ML group and 75 to the WL-MG group. Over a follow-up of almost 10 years, 97 participants encountered the primary endpoint. The WG group had the highest incidence of 25.59%, the WL-MG group had the lowest incidence of 9.33% and the WL-ML group had 21.18% (P = 0.040). In the fourth adjusted Cox model, the WL-MG group achieved significantly decreased odds of the primary endpoint compared with the WG group (hazard ratio [HR] 0.33, 95% confidence interval [CI] [0.12, 0.87], P = 0.026), whilst the WL-ML group did not (HR 0.91, 95% CI [0.47, 1.78], P = 0.670). Among the participants with weight loss, when SMMC/WC reached around 50%, this HR soared to approximately two-fold.

CONCLUSIONS

The participants gaining SMM along with weight loss achieved the lowest odds of adverse cardiovascular events, whilst those who lost SMM along with weight loss had comparable cardiovascular risk with those gaining weight. The more muscle lost during weight loss, the greater the harm. The cardiovascular effects of weight loss were modulated by whether the participants gained SMM meanwhile losing weight.

Assessment of lower limb muscle strength can predict fall risk in patients with chronic liver disease

Falls are caused by a combination of factors, including loss of lower limb muscle strength (LMS), and associated with declined performance status (PS). Age-related sarcopenia is generally associated with decreased muscle mass and strength of lower limb muscle but without a noticeable loss of those of upper limb or trunk muscle. However, no reports have focused on falls or LMS in chronic liver disease (CLD) patients. This study is the first to analyze the risk factors for falls in patients with CLD, focusing on LMS measurement using the Locomoscan. This study enrolled 315 CLD patients whose LMS was measured. The patients who experienced falls more than 1 year ago or during the observation period were classified as those who experienced falls. We found that risk factors for falls were PS1/2 and decreased LMS (< 0.32 N/kg). The group with sarcopenia had a higher frequency of decreased LMS (54 vs. 26%, p = 0.001) and falls (24 vs. 4.4%, p < 0.001) compared to the non-sarcopenia group. This study found that decreased LMS was an independent risk factor for falls. Assessment of LMS may be used as a better marker associated with the risk of falls in patients with CLD.

Association between the Suita Score and Body Composition in Japanese Adults: A Large Cross-Sectional Study

The purpose of this study was to clarify the relationship between the Suita score (a prediction model for the development of cardiovascular disease) and body composition in Japanese health check-up subjects (6873 men and 8685 women). The Suita score includes 8 items (age, gender, smoking, diabetes, blood pressure, low-density lipoprotein, high-density lipoprotein, and chronic kidney disease). Factors associated with the Suita score within body composition-related parameters (body mass index (BMI), waist circumference (WC), fat mass index, fat-free mass index, fat mass to fat-free mass ratio (F-FF ratio), and water mass index) as assessed by bioelectrical impedance analysis were examined. The mean age of subjects was 54.8 years in men and 52.8 years in women (p < 0.0001). The mean BMI was 23.9 kg/m2 in men and 21.8 kg/m2 in women (p < 0.0001). Diabetes mellitus was found in 1282 subjects (18.7%) among men and 816 subjects (9.4%) among women (p < 0.0001). The mean Suita score was 42.0 in men and 29.6 in women (p < 0.0001). In multivariate analysis, WC (p < 0.0001), F-FF ratio (p < 0.0001), and water mass index (p < 0.0001) were independent factors linked to the Suita score for both genders. In conclusion, body composition can be associated with the Suita score in Japanese adults receiving health check-ups.

Fat-to-muscle ratio is associated with insulin resistance and cardiometabolic disorders in adults with type 1 diabetes mellitus

AIMS

This study aimed to investigate the correlation of the fat-to-muscle ratio (FMR) with insulin resistance (IR) and cardiometabolic disorders (CMD) in patients with type 1 diabetes mellitus (T1DM).

MATERIALS AND METHODS

We retrospectively recruited 420 adults with T1DM [52.6% men, median age 32.4 (24.5, 43.0) years]. Body composition was assessed by bioelectrical impedance analysis and FMR was calculated. The characteristics of the overall participants were compared between tertiles of FMR. Logistic regression analyses were performed to assess the association of FMR tertiles with IR and cardiometabolic risk factors.

RESULTS

Median age and median haemoglobin A1c of all participants were 32.4 (24.5, 43.0) years and 7.4 (6.5, 8.7)%, respectively. The prevalence of IR and CMD was 18% and 38.6%. The FMR significantly differed between men and women [0.39 (0.31, 0.53) vs. 0.74 (0.63, 0.92), respectively, p < .001]. The proportion of IR and CMD gradually increased as the FMR increased. The multivariable-adjusted odd ratios for IR and CMD in FMR tertile 3 compared with tertile 1 were 4.8 [95% confidence interval (CI): (1.9, 12.1)] and 9.7 (95% CI: 4.2, 22.3), respectively, in men. For women, the corresponding odd ratios were 4.0 (95% CI: 1.2, 12.9) for IR and 5.8 (95% CI: 2.4, 13.6) for CMD.

CONCLUSIONS

FMR is associated with IR and CMD in adults with T1DM and could be used as a promising parameter for targeting treatment in T1DM.

Sarcopenia as an important determinant for adverse outcomes in patients with pyogenic liver abscess

Background

Low muscle mass/sarcopenia has been associated with poor prognosis in many diseases, but its clinical significance in pyogenic liver abscess (PLA) remains unclear. The purpose of this study is to investigate the relationship between muscle mass and prognosis of patients with PLA.

Methods

A total of 154 adult patients with PLA hospitalized at Tongji Hospital (Wuhan, Hubei, China) between October 2011 and June 2021 were included in this retrospective analysis. Muscle-fat related indicators were measured by computed tomography (CT) images at the third lumbar vertebra (L3) level. The data of patients between the sarcopenia group and non-sarcopenia group were compared. Multivariate logistic regression and receiver operating characteristic (ROC) curve analyses were performed.

Results

The skeletal muscle index (SMI) was independently associated with adverse outcomes (95% CI [0.649-0.954], P = 0.015) of PLA in multivariate logistic regression analysis. This conclusion held true in sex-specific subgroup analysis. ROC analysis indicated that SMI may predict adverse outcomes in both male (area under the ROC curve [AUC], 0.718; cut-off, 52.59; P < 0.001) and female (AUC, 0.714; cut-off, 38.39; P = 0.017) patient populations.

Conclusions

Sarcopenia serves as an independent risk factor for poor prognosis in PLA and patients with sarcopenia may be more prone to adverse outcomes.

Anticipated correlation between lean body mass to visceral fat mass ratio and insulin resistance: NHANES 2011-2018

Objective

The relationship between body composition and insulin resistance (IR) is controversial. This study aimed to thoroughly examine the correlation between adipose tissue, lean body mass, and IR as evaluated by the Homeostatic Model Assessment (HOMA-IR).

Methods

In this cross-sectional study, we utilized data from the National Health and Nutrition Examination Survey (NHANES) conducted between 2011 and 2018. Our study included 4981 subjects, and we employed multiple linear regression, smoothed curve fitting, threshold, and saturation effect analysis to investigate the relationship between lean body mass, visceral fat mass, and IR. Also, we used the lean body mass to visceral fat ratio (Log LM/VFM) as a proxy variable to analyze its association with IR alone.

Results

The study discovered a negative link between lean body mass and IR, but the visceral fat mass was positively correlated after correcting for covariates. A negative correlation was observed when the alternative variable Log LM/VFM was analyzed separately for its association with IR. This association was present regardless of whether the exposure variables were analyzed as continuous or categorical. The data analysis revealed a nonlinear relationship between Log LM/VFM and IR, as evidenced by the generalized additive model. In addition, a threshold effect with a critical value of 1.80 and a saturation effect with a critical point of 2.5 were also observed. Further subgroup analysis for sex, age, BMI, active levels, hypertension, and diabetes showed considerable robustness between the relationship of Log LM/VFM and IR.

Conclusion

Maintaining a proper ratio of lean body mass and visceral fat is beneficial for decreasing IR.

Sarcopenic obesity: epidemiology, pathophysiology, cardiovascular disease, mortality, and management

Sarcopenic obesity is defined as the coexistence of sarcopenia and obesity in the same individual, characterized by of the co-presence of body fat accumulation and muscle loss. This condition is currently a major concern as it is associated with frailty and disabilities such as cardiovascular disease, fractures, dementia, cancer, and increased all-cause mortality. Particularly, older individuals remain at risk of sarcopenic obesity. Progress at several levels is needed to improve the global prognostic outlook for this condition, including the elaboration and implementation of a more uniform definition that may favor the identification and specification of prevalence by age group. Furthermore, improvements in the understanding of the pathogenesis of sarcopenic obesity may lead to the development of more specific therapeutic interventions to improve prognosis. We reviewed the knowledge on sarcopenic obesity and its associations with cardiovascular diseases and mortality.

Characteristics of resistance training-based protocols in older adults with sarcopenic obesity: a scoping review of training procedure recommendations

Background

Sarcopenic obesity (SO) is a clinical and functional disease characterized by the coexistence of obesity and sarcopenia. Resistance training (RT) characteristics for older adults with sarcopenia or obesity are already well established in the scientific literature. Nonetheless, we still do not know how detailed the RT protocols are described for older adults with SO. Therefore, we aimed to analyze the characteristics of RT programs, including each of their variables, recommended for older adults with SO.

Methods

This is a scoping review study that was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analysis for Scoping Reviews. The search was carried out until November 2022 in PubMed/MEDLINE, EMBASE, Cochrane Library, Web of Science, Scopus, LILACS, Google Scholar, and medRxiv databases. The studies included SO diagnosis and RT as an intervention strategy. The RT variables analyzed were as follows: exercise selection, the volume of sets, the intensity of load, repetition cadence, rest interval between sets, and weekly frequency.

Results

A total of 1,693 studies were identified. After applying the exclusion criteria, 15 studies were included in the final analysis. The duration of the RT intervention ranged from 8 to 24 weeks. All studies included full-body routines, with single/multi-joint exercises. Regarding the volume of sets, some studies fixed it in three sets, whereas others varied between one and three sets. The load was reported by repetition range and the weight lifted, elastic-band color/resistance, percentage of one repetition maximum, or perceived exertion scale. Repetition cadence was fixed in some studies, while it was self-selected between concentric and eccentric phases in others. The interval between sets of rest varied from 30 to 180 s. All studies reported progression overload during the interventions. Not all studies reported how the exercise selection, repetition cadence, and rest interval were made.

Conclusion

The characteristics of RT protocols and their variables prescribed in the literature for older adults with SO were mapped. The lack of detail on some training variables (i.e., exercise selection, repetition cadence, and rest interval) was identified. RT protocols are heterogeneous and described only partially among studies. The recommendations for RT prescription details in older adults with SO are provided for future studies.

Systematic review registration

https://osf.io/wzk3d/.

The association between muscle-to-fat ratio and cardiometabolic risks: The China National Health Survey

BACKGROUND

The relationship between muscle mass and fat mass might be an indicator to assess the cardiometabolic risk independently from overweight/obesity, but evidence from a representative general Chinese population is lacking.

OBJECTIVE

To understand the age- and sex-specific associations between muscle-to-fat ratio (MFR) and cardiometabolic risks in Chinese population.

METHODS

31,178 (12,526 men and 18,652 women) subjects from the China National Health Survey were included. Muscle mass and fat mass were assessed by a bioelectrical impedance device. MFR was calculated as muscle mass divided by fat mass. Systolic blood pressure (SBP) and diastolic blood pressure (DBP), serum lipids, fasting plasma glucose and serum uric acid were measured. General linear regressions, quantile regressions and restricted cubic-spline (RCS) regressions were applied to assess the effect of MFR on cardiometabolic profiles.

RESULTS

Per unit increase of MFR was associated with a 0.631 (0.759-0.502) mmHg SBP decrease in men, 2.648 (3.073-2.223) in women; 0.480 (0.568-0.392) mmHg DBP decrease in men, 2.049 (2.325-1.774) in women; a 0.054 (0.062-0.046) mmol/L total cholesterol decrease in men, 0.147 (0.172-0.122) in women; 0.084 (0.098-0.070) mmol/L triglycerides decrease in men, 0.225 (0.256-0.194) in women; a 0.045 (0.054-0.037) mmol/L low-density lipoprotein decrease in men, 0.183 (0.209-0.157) in women; a 2.870 (2.235-3.506) μmol/L serum uric acid decrease in men, 13.352 (14.967-11.737) in women; and a 0.027 (0.020-0.033) mmol/L high-density lipoprotein increase in men, 0.112 (0.098-0.126) mmol/L in women. The effect in overweight/obese people was much significant than in under/normal weight counterparts. The RCS curves revealed both linear and non-linear relationships between increased MFR and lower cardiometabolic risk.

CONCLUSIONS

Muscle-to-fat ratio is independently associated with multiple cardiometabolic parameters among Chinese adults. Higher MFR is related with better cardiometabolic health, and the effect is much significant in overweight/obese people and women.

Multicompartment body composition analysis in older adults: a cross-sectional study

BACKGROUND

During aging, changes occur in the proportions of muscle, fat, and bone. Body composition (BC) alterations have a great impact on health, quality of life, and functional capacity. Several equations to predict BC using anthropometric measurements have been developed from a bi-compartmental (2-C) approach that determines only fat mass (FM) and fat-free mass (FFM). However, these models have several limitations, when considering constant density, progressive bone demineralization, and changes in the hydration of the FFM, as typical changes during senescence. Thus, the main purpose of this study was to propose and validate a new multi-compartmental anthropometric model to predict fat, bone, and musculature components in older adults of both sexes.

METHODS

This cross-sectional study included 100 older adults of both sexes. To determine the dependent variables (fat mass [FM], bone mineral content [BMC], and appendicular lean soft tissue [ALST]) whole total and regional dual-energy X-ray absorptiometry (DXA) body scans were performed. Twenty-nine anthropometric measures and sex were appointed as independent variables. Models were developed through multivariate linear regression. Finally, the predicted residual error sum of squares (PRESS) statistic was used to measure the effectiveness of the predicted value for each dependent variable.

RESULTS

An equation was developed to simultaneously predict FM, BMC, and ALST from only four variables: weight, half-arm span (HAS), triceps skinfold (TriSK), and sex. This model showed high coefficients of determination and low estimation errors (FM: R²_adj: 0.83 and SEE: 3.16; BMC: R²_adj: 0.61 and SEE: 0.30; ALST: R²_adj: 0.85 and SEE: 1.65).

CONCLUSION

The equations provide a reliable, practical, and low-cost instrument to monitor changes in body components during the aging process. The internal cross-validation method PRESS presented sufficient reliability in the model as an inexpensive alternative for clinical field use.

The Effects of Different Exercise Training Types on Body Composition and Physical Performance in Older Adults with Sarcopenic Obesity: A Systematic Review and Meta-Analysis

OBJECTIVES

To carry out a systematic review and meta-analysis to verify the effects of different exercise training types on body composition and physical performance in older adults with sarcopenic obesity (SO).

DESIGN

Systematic review and meta-analysis.

SETTING AND PARTICIPANTS

Older adults (≥60 years).

METHODS

Database searches were performed in MEDLINE (via PubMed), EMBASE, Cochrane Library, Web of Science, SCOPUS, and LILACS on January 10th, 2023. We included: randomized and/or controlled clinical trials; physical exercise as an intervention; analysis of body composition and/or muscle function; and sarcopenic obesity diagnosis. We used the Risk of Bias 2 tool and PEDro scale. The GRADE certainty of evidence was also performed.

RESULTS

Fourteen studies were included in the systematic review and nine studies in the meta-analysis. A decrease in body fat (%) favoring the exercise group was identified (SMD: -0.34 [95% CI: -0.53 to -0.16]; p=0.0003) (GRADE: ⊕⊕⊕◯ Moderate). Only resistance training showed fat reduction (SMD: -0.27 [95% CI: -0.48 to -0.06]; p=0.01). Increases in upper (SMD: 0.41 [95% CI: 0.04 to 0.78]; p=0.03) (GRADE: ⊕⊕◯◯ Low) and lower (SMD: 0.80 [95% CI: 0.22 to 1.39]; p=0.007) (GRADE: ⊕⊕⊕⊕ High) limb strength was identified with exercise. Chair stand test showed increases with exercise (SMD: 0.73 [95% CI: 0.40 to 1.07]; p<0.0001) (GRADE: ⊕⊕⊕⊕ High), especially for resistance training (SMD: 0.62 [95% CI: 0.21 to 1.02]; p=0.003) and combined training (SMD: 0.99 [95% CI: 0.40 to 1.57]; p=0.0005). The PEDro scale for the studies in our review ranged from 3 to 8 (mean = 5.8 (1.6)), meaning fair methodological quality, and most studies were overall judged with at least low/some concerns in terms of risk of bias.

CONCLUSION AND IMPLICATIONS

Overall, moderate to high certainty of evidence was found for body fat, lower limb strength, and chair stand test. On the other hand, low certainty of evidence was found for upper limb strength. Resistance, combined, and aerobic training evoked divergent results between the variables analyzed. Although promising, our results should be considered sparingly, but may guide additional exercise recommendations to improve specific health parameters in older adults with SO.

Comparative Analysis of Intrinsic Capacity Impairments, Determinants, and Clinical Consequences in Older Community-Dwellers in Japan and Taiwan: Longitudinal Studies Showing Shared Traits and Distinct Presentations

OBJECTIVES

Despite the recognized impact of intrinsic capacity (IC) impairment on healthy aging, international comparisons in different sociocultural contexts are scarce. This study aimed to compare IC impairment among community-dwelling older adults in Japan and Taiwan to explore the context of healthy aging in different countries.

DESIGN

Comparative observational study.

SETTING

National Institute for Longevity Sciences-Longitudinal Study of Aging (NILS-LSA) in Japan and Longitudinal Aging Study of Taipei (LAST) in Taiwan.

PARTICIPANTS

794 individuals (age range, 60.0-86.5 years) from NILS-LSA and 1,358 (60.0-96.7 years) from LAST.

MEASUREMENTS

IC impairment was evaluated across the domains of locomotion, cognition, vitality, sensory capacity, and psychological well-being. Participants were categorized as having impaired IC or healthy. We investigated associations between IC impairment, falls, and all-cause mortality.

RESULTS

IC impairment was present in 54.9% and 37.3% of participants in the NILS-LSA and LAST cohorts, respectively. Male NILS-LSA participants with impaired IC (odds ratio [OR]:1.50, 95% confidence interval [CI]:1.03-2.20), with hearing loss (OR:1.98, 95% CI:1.00-3.90) were more likely to fall. In LAST, impaired locomotion (OR:2.14, 95% CI:1.46-3.14) increased the risk of falls. Men with impaired IC (hazard ratio [HR]; 2.14, 95% CI:1.10-4.15) and visual impairment (HR:2.21, 95% CI:1.15-4.25) and women with impaired psychological well-being (HR:4.94, 95% CI:1.28-18.97) in the NILS-LSA cohort had greater risk for all-cause mortality; however, this was not shown for LAST participants.

CONCLUSION

The prevalence and distribution of IC impairment and associated biomarkers differed significantly between participants in Japan and Taiwan. However, the associations with adverse outcomes remained similar, emphasizing the need for tailored interventions for healthy aging.

Sex-different changes of body composition in aging: a systemic review

OBJECTIVE

Aging causes changes in body composition, in which differences in the distribution and amount of fat and muscle tissue affect the development of various diseases according to sex. We conducted a systemic review of the literature and examined the relationship between body composition differences and related health conditions or diseases in older men and women.

METHODS

Three different electronic databases (MEDLINE, Web of Science, and Embase) were used to find articles from 2000 until March 2022. Information on the study design characteristics, setting, measure of body composition, and health outcomes was extracted.

RESULTS

A total of 217 articles were retrieved, and 28 studies met the inclusion criteria. The included studies showed that older men have larger skeletal muscle mass (sMM) than women, while older women have larger fat mass (FM) than men. sMM has a favorable effect on physical performance, bone density, metabolism, cognitive function, and mortality in both men and women; however, the effects of sMM in women are less significant and even negligible compared to those in men. FM is significantly unfavorable for physical performance in women but sometimes favorable or unfavorable for glucose level and cognitive and lung function according to location. FM in men is usually less important for function, bone density, glucose level, and cognitive function than in women.

CONCLUSION

Changes in muscle and fat distribution according to aging and their correlation with health outcomes differ according to sex. Muscle mass may not always be favorable, and fat mass may not always be unfavorable in older adults.

Dietary Fiber Intake Is Related to Skeletal Muscle Mass, Body Fat Mass, and Muscle-to-Fat Ratio Among People With Type 2 Diabetes: A Cross-Sectional Study

Objectives

To investigate the relationship between dietary fiber intake and skeletal muscle mass, body fat mass, and muscle-to-fat ratio (MFR) among men and women with type 2 diabetes (T2D).

Methods

This cross-sectional study involved 260 men and 200 women with T2D. Percent skeletal muscle mass (%) or percent body fat mass (%) was calculated as (appendicular muscle mass [kg] or body fat mass [kg]/body weight [kg]) × 100. MFR was calculated as appendicular muscle mass divided by body fat mass. Information about dietary fiber intake (g/day) was obtained from a brief-type self-administered diet history questionnaire.

Results

Dietary fiber intake was correlated with percent body fat mass (r = -0.163, p = 0.021), percent skeletal muscle mass (r = 0.176, p = 0.013), and MFR (r = 0.157, p = 0.026) in women. However, dietary fiber intake was not correlated with percent body fat mass (r = -0.100, p = 0.108), percent skeletal muscle mass (r = 0.055, p = 0.376), and MFR (r = 0.065, p = 0.295) in men. After adjusting for covariates, dietary fiber intake was correlated with percent body fat mass (β = 0.229, p = 0.009), percent skeletal muscle mass (β = 0.364, p < 0.001), and MFR (β = 0.245, p = 0.006) in women. Further, dietary fiber intake was related to percent skeletal muscle mass (β = 0.221, p = 0.008) and tended to be correlated with percent body fat mass (β = 0.148, p = 0.071) in men.

Conclusion

Dietary fiber intake was correlated with skeletal muscle mass, body fat mass, and MFR among women with T2D.

Multimodal Diagnostic Approaches to Advance Precision Medicine in Sarcopenia and Frailty

Sarcopenia, defined as the loss of muscle mass, strength, and function with aging, is a geriatric syndrome with important implications for patients and healthcare systems. Sarcopenia increases the risk of clinical decompensation when faced with physiological stressors and increases vulnerability, termed frailty. Sarcopenia develops due to inflammatory, hormonal, and myocellular changes in response to physiological and pathological aging, which promote progressive gains in fat mass and loss of lean mass and muscle strength. Progression of these pathophysiological changes can lead to sarcopenic obesity and physical frailty. These syndromes independently increase the risk of adverse patient outcomes including hospitalizations, long-term care placement, mortality, and decreased quality of life. This risk increases substantially when these syndromes co-exist. While there is evidence suggesting that the progression of sarcopenia, sarcopenic obesity, and frailty can be slowed or reversed, the adoption of broad-based screening or interventions has been slow to implement. Factors contributing to slow implementation include the lack of cost-effective, timely bedside diagnostics and interventions that target fundamental biological processes. This paper describes how clinical, radiographic, and biological data can be used to evaluate older adults with sarcopenia and sarcopenic obesity and to further the understanding of the mechanisms leading to declines in physical function and frailty.