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

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.

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.

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.