Effect of sarcopenia on cardiovascular disease risk factors in obese postmenopausal women

Sarcopenic obesity is associated with cardiometabolic multimorbidity in Chinese middle-aged and older adults: a cross-sectional and longitudinal study

OBJECTIVES

Sarcopenic obesity (SO) has been found to increase the risk of metabolic disorders, however, its relationship with cardiometabolic multimorbidity (CMM) remains unexplored. This study aims to investigate the potential association between SO and CMM in the middle-aged and older population.

METHODS

Our study subjects were from CHARLS. SO was defined as the combination of impaired grip strength (grip strength <28 kg for men and <18 kg for women) and increased body mass index (BMI ≥25 kg/m2). CMM was defined as having two or more cardiometabolic diseases, including diabetes mellitus, stroke, and heart disease. The participants were divided into four groups according to their sarcopenia and obesity status, and logistic regression analysis was used to examine the association between SO and CMM.

RESULTS

A total of 15,252 study subjects were included in the cross-sectional study, with an average age of 60.6 years and a male proportion of 47.4%. In the cross-sectional analysis conducted in 2015, the prevalence of CMM was highest in the SO group (9.1%), followed by the obesity (3.7%) and sarcopenia (3.5%) group. After adjustment for confounding factors, SO [OR (95%CI): 2.453 (1.742-3.455)], sarcopenia [OR (95% CI): 1.601 (1.157-2.217)], obesity [OR (95% CI): 1.446 (1.107-1.888)] were all observed to be associated with CMM, with the strongest association in the SO group. Furthermore, in the longitudinal analysis, only the SO group demonstrated a significant risk for developing CMM [OR (95% CI): 2.302 (1.239-4.228)].

CONCLUSIONS

SO was independently and positively associated with CMM in middle-aged and older population.

Identification of factors associated with sarcopenic obesity development: Literature review and expert panel voting

Sarcopenic obesity (SO) is defined as the combination of excess fat mass (obesity) and low skeletal muscle mass and function (sarcopenia). The identification and classification of factors related to SO would favor better prevention and diagnosis. The present article aimed to (i) define a list of factors related with SO based on literature analysis, (ii) identify clinical conditions linked with SO development from literature search and (iii) evaluate their relevance and the potential research gaps by consulting an expert panel. From 4746 articles screened, 240 articles were selected for extraction of the factors associated with SO. Factors were classified according to their frequency in the literature. Clinical conditions were also recorded. Then, they were evaluated by a panel of expert for evaluation of their relevance in SO development. Experts also suggested additional factors. Thirty-nine unique factors were extracted from the papers and additional eleven factors suggested by a panel of experts in the SO field. The frequency in the literature showed insulin resistance, dyslipidemia, lack of exercise training, inflammation and hypertension as the most frequent factors associated with SO whereas experts ranked low spontaneous physical activity, protein and energy intakes, low exercise training and aging as the most important. Although literature and expert panel presented some differences, this first list of associated factors could help to identify patients at risk of SO. Further work is needed to confirm the contribution of factors associated with SO among the population overtime or in randomized controlled trials to demonstrate causality.

Associations Between Gait Speed and Fat Mass in Older Adults

Purpose

Although both gait speed and fat mass are crucial for healthy aging, evidence suggests that the associations between these components remain unclear. Therefore, the main purpose of the study was to examine the associations between gait speed and fat mass.

Patients and Methods

In this cross-sectional study, we recruited 643 older men and women aged >60 years. Fat mass was assessed using bioelectrical impedance analysis, while gait speed was determined by calculating the time an individual has taken to walk across a 4.6-m distance. Receiver operating characteristic (ROC) curves and odds ratios (OR) were performed to determine cut-off points and mutual associations.

Results

In older men, the optimal threshold of gait speed to detect high level of fat mass was 1.40 m/s with the area under the curve (AUC) being 0.82 (95% CI 0.76-0.89, p < 0.001). In older women, the optimal cut-off point was 1.37 m/s (AUC = 0.85, 95% CI 0.81-0.90, p < 0.001). Older men and women who walked below the newly developed threshold were approximately 12 times more likely to have high level of fat.

Conclusion

In summary, newly developed cut-off points of gait speed have adequate discriminatory ability to detect older men and women with high level of fat mass. Although gait speed may be considered as a satisfactory screening tool for fat mass, its utility in clinical practice needs to be further investigated.

Association between sarcopenia-related traits and cardiovascular diseases: a bi-directional Mendelian randomization study

Background

The two geriatric diseases, sarcopenia and cardiovascular disease (CVD), often coexist, yet the causal relationship is unclear. However, few studies focus on the effect of muscle mass on CVD. This comprehensive study is dedicated to unearthing the potential connection between sarcopenia-related traits and CVD at the genetic level.

Method

A two-sample bi-directional Mendelian randomization (MR) study was conducted. In the first stage, we performed MR analysis regarding coronary heart disease (CHD), stroke, and myocardial infarction (MI) as exposure factors to reveal their effect on appendicular lean mass (ALM) and hand grip strength. In the second stage, we reverse the position of exposures and outcomes. The inverse variance weighted (IVW) method was used as the primary approach to reveal the potential causation between the exposure and outcome.

Results

The results of the IVW method revealed a negative causal effect of ALM on CHD (OR = 0.848, 95% CI = 0.804 to 0.894, p = 8.200E-10), stroke (OR = 0.931, 95% CI = 0.890 to 0.975, p = 2.220E-03), and MI (OR = 0.810, 95% CI = 0.694 to 0.901, p = 1.266E-13). Additionally, the left-hand grip strength is a significant protective factor for CHD (OR = 0.737, 95% CI = 0.601 to 0.904, p = 3.353E-03) and MI (OR = 0.631, 95% CI = 0.515 to 0.765, p = 2.575E-06), but is not causally linked to the stroke (OR = 0.971, 95% CI =0.829 to 1.139, p = 0.720). Meanwhile, the same conclusion about the effect of right-hand grip strength on CHD (OR = 0.681, 95% CI = 0.558 to 0.832, p = 1.702E-05), MI (OR = 0.634, 95% CI = 0.518 to 0.776, p = 9.069E-06), and stroke (OR = 1.041, 95% CI = 0.896 to 1.209, p = 0.604) was obtained. However, no significant causal effect of CVD (CHD, stroke, MI) on sarcopenia-related traits (ALM, handgrip strength) was found.

Conclusion

There is a unidirectional causal relationship between sarcopenia and CVD. The loss of muscle mass and strength has a significant causal role in promoting the occurrence and development of CVD, providing a reference for the prevention and treatment of comorbidities in older people.

Relationship between monounsaturated fatty acids and sarcopenia: a systematic review and meta-analysis of observational studies

Accumulating evidence suggests that fatty acids (FAs) play an essential role in regulating skeletal muscle mass and function throughout life. This systematic review and meta-analysis aimed to examine the relationship between dietary or circulatory levels of monounsaturated FAs (MUFAs) and sarcopenia in observational studies. A comprehensive literature search was performed in three databases (PubMed, Scopus, and Web of Science) from inception until August 2022. Of 414 records, a total of 12 observational studies were identified for this review. Ten studies were meta-analysed, comprising a total of 3704 participants. The results revealed that MUFA intake is inversely associated with sarcopenia (standardized mean difference = - 0.28, 95% CI - 0.46 to - 0.11; p < 0.01). Despite the limited number of studies, our results suggest that lower MUFA intake is associated with a higher risk of sarcopenia. However, the available evidence is still insufficient and further investigations are needed to demonstrate this relationship.

Interactive effects of intrinsic capacity and obesity on the KDIGO chronic kidney disease risk classification in older patients with type 2 diabetes mellitus

BACKGROUND

Intrinsic capacity (IC) is a novel concept focusing on normal and healthy aging. The effect of IC on the risk of chronic kidney disease (CKD) according to KDIGO category in older type 2 diabetes mellitus (T2DM) patients has rarely been studied. We investigated whether a decline in IC is associated with the risk of CKD according to KDIGO 2012 categories.

METHODS

This is a cross-sectional study. The exposure variables (IC score and body mass index) and outcome variable (KDIGO categories of the risk of CKD) were collected at the same timepoint. A total of 2482 older subjects with T2DM managed through a disease care program were enrolled. The five domains of IC, namely locomotion, cognition, vitality, sensory, and psychological capacity were assessed. Based on these domains, the IC composite score was calculated. CKD risk was classified according to the KDIGO 2012 CKD definition. Univariate and multivariate analyses were used to assess the association between IC score and KDIGO categories of risk of CKD.

RESULTS

The KDIGO CKD risk category increased in parallel with IC score (p for trend < 0.0001). In multivariate analysis, compared to those with an IC score 0, the odds ratio of having a KDIGO moderately increased to very high risk category of CKD was 1.76 (1.31-2.37) times higher for those with an IC score of 2-5. Furthermore, an increased IC score was associated with a higher prevalence of moderate and severe obesity. Moreover, there was a synergistic interaction between IC score and obesity on the KDIGO moderately increased to very high risk category of CKD (synergy index = 1.683; 95% CI 0.630-3.628), and the proportion of the KDIGO moderately increased to very high risk category of CKD caused by this interaction was 25.6% (attributable proportion of interaction = 0.256).

CONCLUSIONS

Our findings indicate that IC score may be closely related to the KDIGO moderately increased to very high risk category of CKD. In addition, there may be a synergistic interaction between IC score and obesity, and this synergistic interaction may increase the KDIGO CKD risk stage.

Body Mass Trajectory Affects the Long-Term Occurrence of Metabolic Syndrome in Adult Patients with Severe Obesity

Independently of absolute BMI values, the amount, onset date, and duration of early body weight gain may influence cardio-metabolic health later in adulthood. Values of cardiac and metabolic variables from a cohort study of morbidly obese patients were retrospectively analyzed to study the association between early weight history and metabolic syndrome (MetS) occurrence in adults. Of 950 patients with severe morbid obesity (age 44.3 ± 13.8 y, BMI 42.5 ± 7.0 kg/m²), 31.4% had started excess weight gain in childhood (CH), 19.9% in adolescence (ADO), and 48.7% in adulthood (AD). Despite different BMI values, MetS prevalence (57.8%) was not significantly different in the three groups (54.4% CH vs. 57.7% ADO vs. 59.8% AD, p = 0.59). The overweight onset period was not significantly associated with the development of MetS in adults (ADO: OR = 1.14 [0.69-1.92], p = 0.60; AD: OR = 0.99 [0.62-1.56], p = 0.95) despite a higher BMI in the early obesity onset group. Weight gain of more than 50% after age 18 years significantly increased the risk of MetS (OR = 1.75 [1.07-2.88], p = 0.026). In addition to crude BMI values, analysis of body mass trajectories is a relevant clinical tool in the assessment of metabolic risk, suggesting that the magnitude of weight gain may be more important for metabolic syndrome progression than the period of obesity onset.

Circulating miR-29b decrease in response to sarcopenia in patients with cardiovascular risk factors in older Chinese

Introduction

Sarcopenia is a clinical syndrome characterized by a progressive and extensive decline in skeletal muscle mass, muscle strength, and function. Sarcopenia and cardiovascular diseases (CVDs) can coexist, which further decreases the quality of life of patients, and increases the mortality rate. MicroRNAs (miRNAs) are unique posttranscriptional regulators of gene expression whose function in aging-related sarcopenia and CVDs has recently begun to unravel. The aim of the present study is to investigate the relationship between sarcopenia and cardiovascular risk factors (CVRF) in the Chinese elderly and describe the circulating miRNAs in sarcopenia patients with the intention of identifying novel diagnostic and therapeutic tools.

Methods

The well-established CVRF of diabetes, hypertension, and dyslipidemia were assessed. Multiple logistic regression analyses and linear regressions were used to evaluate the components of CVRF and the number of CVRF in elderly patients with sarcopenia. Moreover, we used real-time RT-PCR to measure the abundance of the CVRF-related miRNAs in the plasma of a cohort of 93 control and sarcopenia individuals, including miR-29b, miR-181a, and miR-494.

Results

We found that CVRF was associated with a high prevalence of sarcopenia in elderly Chinese populations After adjusting for potential confounders. Furthermore, hypertension and dyslipidemia, but not diabetes, were found to be significantly associated with sarcopenia. A linear increase in the prevalence of sarcopenia was found to be associated with the number of CVRF components in the elderly population. We found that plasma miR-29b levels were significantly down-regulated in response to sarcopenia in the elderly with CVRF. In particular, there was a remarkable correlation between miR-29b and appendicular skeletal muscle mass (ASM)/height2. Collectively, knowledge of CVRF, particularly hypertension and dyslipidemia, may help predict the risk of sarcopenia in the elderly. Our data also show that circulating miR-29b can be considered as possible biomarkers for sarcopenia, which may also be used in the CVD assessment of these patients.

Discussion

We found that the prevalence of sarcopenia was significantly proportional to the number of CVRF components. In particular, hypertension and dyslipidemia were significantly associated with a higher risk of sarcopenia in the adjusted models. Moreover, our study has been proven that c-miRNAs may be considered as possible biomarkers for sarcopenia as a new diagnostic tool to monitor response to treatment. There is also a pressing need for further research on sarcopenia and CVRF to understand their relationship and mechanism. These can provide more evidence to develop potential interventions to improve clinical outcomes.

Impact of Cortisol on Reduction in Muscle Strength and Mass: A Mendelian Randomization Study

CONTEXT

Prolonged exposure to pathological cortisol, as in Cushing's syndrome causes various age-related disorders, including sarcopenia. However, it is unclear whether mild cortisol excess, for example, accelerates sarcopenia due to aging or chronic stress.

OBJECTIVE

We used Mendelian randomization (MR) analysis to assess whether cortisol was causally associated with muscle strength and mass.

METHODS

Three single-nucleotide polymorphisms associated with plasma cortisol concentrations in the CORtisol NETwork consortium (n = 12 597) were used as instrumental variables. Summary statistics with traits of interest were obtained from relevant genome-wide association studies. For the primary analysis, we used the fixed-effects inverse-variance weighted analysis accounting for genetic correlations between variants.

RESULTS

One SD increase in cortisol was associated with SD reduction in grip strength (estimate, -0.032; 95% CI -0.044 to -0.020; P = 3e-04), whole-body lean mass (estimate, -0.032; 95% CI, -0.046 to -0.017; P = 0.004), and appendicular lean mass (estimate, -0.031; 95% CI, -0.049 to -0.012; P = 0.001). The results were supported by the weighted-median analysis, with no evidence of pleiotropy in the MR-Egger analysis. The association of cortisol with grip strength and lean mass was observed in women but not in men. The association was attenuated after adjusting for fasting glucose in the multivariable MR analysis, which was the top mediator for the association in the MR Bayesian model averaging analysis.

CONCLUSION

This MR study provides evidence for the association of cortisol with reduced muscle strength and mass, suggesting the impact of cortisol on the development of sarcopenia.

Utilization of Mid-Thigh Magnetic Resonance Imaging to Predict Lean Body Mass and Knee Extensor Strength in Obese Adults

Purpose

To train and test a machine learning model to automatically measure mid-thigh muscle cross-sectional area (CSA) to provide rapid estimation of appendicular lean mass (ALM) and predict knee extensor torque of obese adults.

Methods

Obese adults [body mass index (BMI) = 30–40 kg/m², age = 30–50 years] were enrolled for this study. Participants received full-body dual-energy X-ray absorptiometry (DXA), mid-thigh MRI, and completed knee extensor and flexor torque assessments via isokinetic dynamometer. Manual segmentation of mid-thigh CSA was completed for all MRI scans. A convolutional neural network (CNN) was created based on the manual segmentation to develop automated quantification of mid-thigh CSA. Relationships were established between the automated CNN values to the manual CSA segmentation, ALM via DXA, knee extensor, and flexor torque.

Results

A total of 47 obese patients were enrolled in this study. Agreement between the CNN-automated measures and manual segmentation of mid-thigh CSA was high (>0.90). Automated measures of mid-thigh CSA were strongly related to the leg lean mass (r = 0.86, p < 0.001) and ALM (r = 0.87, p < 0.001). Additionally, mid-thigh CSA was strongly related to knee extensor strength (r = 0.76, p < 0.001) and moderately related to knee flexor strength (r = 0.48, p = 0.002).

Conclusion

CNN-measured mid-thigh CSA was accurate compared to the manual segmented values from the mid-thigh. These values were strongly predictive of clinical measures of ALM and knee extensor torque. Mid-thigh MRI may be utilized to accurately estimate clinical measures of lean mass and function in obese adults.

Association Between Overweight Sarcopenic Population and Acute Vertebral Osteoporotic Compression Fractures in Females: Retrospective, Cross-Sectional Study

Background: This study aimed to determine whether the prevalence of acute vertebral osteoporotic compression fractures (VOCF) in the elderly population is related to the distribution of muscles and fat in the human body. Methods: Data of acute VOCF and non-VOCF patients presenting at our institution between January 2018 and May 2020 were analyzed. Patients aged 65 years and older, who underwent body composition test and dual-energy X-ray absorptiometry at the same time were enrolled. After applying exclusion criteria, patients were divided into four groups: normal, sarcopenia without obesity, obesity without sarcopenia, and sarcopenic obesity. Body mass index ≥25 kg/m2 was considered obesity, and sarcopenia was defined as skeletal muscle index lower than 7.0 kg/m2 in males and 5.4 kg/m2 in females. The VOCF rate was analyzed between the groups. Discussion: A total of 461 patients were included, of whom 103 were males. Among them, 163 (35.36%) had normal body composition, 151 (32.75%) had sarcopenia without obesity, 110 (23.86%) had obesity without sarcopenia, and 37 (8.03%) had sarcopenic obesity. The sarcopenic obesity group had the highest rate of acute VOCF (37.8%), which was statistically significant. Specifically, females with sarcopenic obesity and sarcopenia without obesity had significantly higher acute VOCF rates compared to those with normal body compositions. Multivariate analysis showed that sarcopenic obesity was significantly associated with acute VOCF rate overall, as well as in females. Conclusion: Sarcopenic obesity is strongly associated with acute VOCF, especially in females, and it could be an essential criterion for the prevention of acute VOCF.

Relationship Between Low Skeletal Muscle Mass and Arteriosclerosis in Western China: A Cross-Sectional Study

Objectives: This study explored the prevalence and the correlation between low muscle mass and arteriosclerosis in different gender and age groups, to increase the attention paid to the risk factors of arteriosclerosis in the young and middle-aged population. Methods: This was an analytical, cross-sectional study. Data were obtained from healthy individuals recruited from the Health Management Center of W Hospital. The brachial-ankle pulse-wave velocity was used as an indicator of arteriosclerosis, and a bioelectrical impedance analysis was used to assess the body composition. Results: A total of 36,374 subjects (men, 58.4%; women, 41.6%; mean age, 43.74 ± 12.34 years [range, 18-80 years]) participated in this study. The prevalence of low skeletal muscle mass and arteriosclerosis was 17.7 and 53.1%, respectively, in all subjects. Low skeletal muscle mass was significantly associated with arteriosclerosis (OR: 1.435, 95% CI: 1.343-1.533, P < 0.001) in all subjects, and the association remained significant in young age (OR: 1.506, 95% CI: 1.353-1.678, P < 0.001), middle-age (OR: 1.329, 95% CI: 1.195-1.479, P < 0.001), and old age (OR: 1.676, 95% CI: 1.191-2.358, P = 0.003), and also significant in men (OR: 1.559, 95% CI: 1.396-1.740, P < 0.001) and women (OR: 1.266, 95% CI: 1.143-1.401, P < 0.001). Conclusions and Implications: Our results show that the prevalence of low muscle mass and arteriosclerosis is high in the general population, even among middle-aged people and young people, and confirmed that there is a significant independent association between low skeletal muscle mass and arteriosclerosis in all subjects and in different age and gender subgroups.

Sarcopenia in nonalcoholic fatty liver disease and all-cause and cause-specific mortality in the United States

BACKGROUND & AIMS

Nonalcoholic fatty liver disease (NAFLD) has been associated with sarcopenia. However, mortality in the setting of NAFLD-related sarcopenia remains undefined. We aim to determine the all-cause and cause-specific mortality from sarcopenia among adults with NAFLD in the USA.

METHODS

11 065 individuals in the Third National Health and Nutrition Examination Survey were studied and linked mortality through 2015 was analysed. NAFLD was diagnosed based on presence of ultrasonographic hepatic steatosis without other known liver diseases. Sarcopenia was defined as skeletal muscle index determined by bioelectrical impedance analysis. The Cox proportional hazard model was used to assess all-cause mortality and cause-specific mortality, and hazard ratio (HR) adjusted for known risk factors.

RESULTS

During a median follow-up of 23 years or more, sarcopenia was associated with increased all-cause mortality (HR 1.27, 95% confidence interval [CI] 1.11-1.44). Only in individuals with NAFLD, sarcopenia was associated with a higher risk for all-cause mortality, while this association was absent in those without NAFLD. Individuals with both sarcopenia and NAFLD had a higher risk for all-cause mortality (HR 1.28 95% CI 1.06-1.55) compared with those without sarcopenia and NAFLD. Furthermore, sarcopenia was associated with a higher risk for cancer- and diabetes-related mortality among those with NAFLD. This association was not noted in those without NAFLD.

CONCLUSION

In this nationally representative sample of US adults, sarcopenia was associated with a higher risk for all-cause, cancer- and diabetes-related mortality in individuals with NAFLD.

Weight-adjusted waist index reflects fat and muscle mass in the opposite direction in older adults

BACKGROUND

Age-related changes in body composition include decreased muscle mass and preserved or increased fat mass. There is no anthropometric index to assess both muscle and fat mass.

METHODS

Using a cross-sectional sample of 602 participants aged ≥65 years from the Ansan Geriatric study, we evaluated the association of weight-adjusted waist index (WWI) with muscle and fat mass and compared these with body mass index (BMI) and waist circumference (WC). WWI was calculated as WC (cm) divided by the square root of body weight (kg). Body composition was measured using bioelectrical impedance analysis, dual-energy X-ray absorptiometry and abdominal computed tomography.

RESULTS

WWI positively correlated with total abdominal fat area (TFA) (r = 0.421, P < 0.001), visceral fat area (VFA) (r = 0.264, P < 0.001), and percentage of total tissue fat (r = 0.465, P < 0.001), but negatively correlated with appendicular skeletal muscle mass (ASM) (r = -0.511, P < 0.001) and ASM/height2 (r = -0.324, P < 0.001). Mean ASM was highest in the first quartile of WWI (17.85 kg/m2) and showed a decreasing trend, with the lowest value in the fourth WWI quartile (13.21 kg/m2, P for trend <0.001). In contrast, mean TFA was lowest in the first quartile and highest in the fourth WWI quartile (P for trend <0.001). The probability of combined low muscle mass and high fat mass was >3× higher in the fourth WWI quartile than in the lowest quartile (odds ratio 3.22, 95% confidence interval 1.32-7.83).

CONCLUSIONS

WWI is an anthropometric index positively associated with fat mass and negatively associated with muscle mass in older adults.

Sarcopenia and Cardiac Dysfunction

Although muscle loss is part of the natural course of human aging, sarcopenia has been associated with an increased risk of physical disability and mortality in older patients. Many heart failure patients concomitantly develop deficits in muscle mass and strength, resulting in decreased quality of life and exercise capacity. An underlying state of inflammation is central to the development of sarcopenia and muscle wasting in heart failure; however, additional research in human models is needed to further delineate the pathophysiology of muscle wasting in these patients. Previous studies have shed light on many of the potential targets for therapeutic intervention of sarcopenia in heart failure; however, physical exercise remains the prominent beneficial intervention. Future research must explore other therapeutic interventions in randomized, double-blind clinical trials, which may help to supplement exercise regimens. Sarcopenia shows promise as an easily measured predictor of outcomes after transcatheter aortic valve replacement.

Exploring the Impact of Obesity on Skeletal Muscle Function in Older Age

Sarcopenia is of important clinical relevance for loss of independence in older adults. The prevalence of obesity in combination with sarcopenia ("sarcopenic-obesity") is increasing at a rapid rate. However, whilst the development of sarcopenia is understood to be multi-factorial and harmful to health, the role of obesity from a protective and damaging perspective on skeletal muscle in aging, is poorly understood. Specifically, the presence of obesity in older age may be accompanied by a greater volume of skeletal muscle mass in weight-bearing muscles compared with lean older individuals, despite impaired physical function and resistance to anabolic stimuli. Collectively, these findings support a potential paradox in which obesity may protect skeletal muscle mass in older age. One explanation for these paradoxical findings may be that the anabolic response to weight-bearing activity could be greater in obese vs. lean older individuals due to a larger mechanical stimulus, compensating for the heightened muscle anabolic resistance. However, it is likely that there is a complex interplay between muscle, adipose, and external influences in the aging process that are ultimately harmful to health in the long-term. This narrative briefly explores some of the potential mechanisms regulating changes in skeletal muscle mass and function in aging combined with obesity and the interplay with sarcopenia, with a particular focus on muscle morphology and the regulation of muscle proteostasis. In addition, whilst highly complex, we attempt to provide an updated summary for the role of obesity from a protective and damaging perspective on muscle mass and function in older age. We conclude with a brief discussion on treatment of sarcopenia and obesity and a summary of future directions for this research field.

Sarcopenia during COVID-19 lockdown restrictions: long-term health effects of short-term muscle loss

The COVID-19 pandemic is an extraordinary global emergency that has led to the implementation of unprecedented measures in order to stem the spread of the infection. Internationally, governments are enforcing measures such as travel bans, quarantine, isolation, and social distancing leading to an extended period of time at home. This has resulted in reductions in physical activity and changes in dietary intakes that have the potential to accelerate sarcopenia, a deterioration of muscle mass and function (more likely in older populations), as well as increases in body fat. These changes in body composition are associated with a number of chronic, lifestyle diseases including cardiovascular disease (CVD), diabetes, osteoporosis, frailty, cognitive decline, and depression. Furthermore, CVD, diabetes, and elevated body fat are associated with greater risk of COVID-19 infection and more severe symptomology, underscoring the importance of avoiding the development of such morbidities. Here we review mechanisms of sarcopenia and their relation to the current data on the effects of COVID-19 confinement on physical activity, dietary habits, sleep, and stress as well as extended bed rest due to COVID-19 hospitalization. The potential of these factors to lead to an increased likelihood of muscle loss and chronic disease will be discussed. By offering a number of home-based strategies including resistance exercise, higher protein intakes and supplementation, we can potentially guide public health authorities to avoid a lifestyle disease and rehabilitation crisis post-COVID-19. Such strategies may also serve as useful preventative measures for reducing the likelihood of sarcopenia in general and in the event of future periods of isolation.

Prevalence of Sarcopenic Obesity and its Association with Functionality, Lifestyle, Biomarkers and Morbidities in Older Adults: the FIBRA-RJ Study of Frailty in Older Brazilian Adults

OBJECTIVES

To assess the prevalence of sarcopenic obesity and its association with functionality, lifestyle, biomarkers, and morbidities in older adults.

METHODS

The study analyzed cross-sectional data from 270 older adults who participated in phase III of the Frailty in Brazilian Older People Study (Fragilidade em Idosos Brasileiros-Rio de Janeiro, FIBRA-RJ study-2013). They took part in a home interview surveying socioeconomic, demographic, lifestyle, morbidities, and functional data. Blood was collected for biochemical marker analysis and participants' body composition was determined by dual-energy X-ray absorptiometry. For women, the diagnosis of sarcopenic obesity was defined at a body fat percentage ≥38% and appendicular skeletal muscle mass index (ASMMI) <5.45 kg/m2. For men, a fat percentage ≥27% and ASMMI <7.26 kg/m2 was defined as sarcopenic obesity. Multivariate analysis was performed using a multinomial regression model (95% confidence intervals), with sarcopenic obesity as the outcome.

RESULTS

The prevalence of sarcopenic obesity was 29.3%. In the final fitted model, the variables that displayed statistically significant association with sarcopenic obesity were lower gait speed, self-reported medical diagnosis of arthrosis or arthritis, and high levels of glycemia.

CONCLUSION

The study showed a high prevalence of sarcopenic obesity in non-institutionalized older adults in Brazil. The finding that this condition was associated with modifiable risk factors may provide insights into measures directed at prevention and reduction of the risk of sarcopenic obesity in this population subgroup.

Semiautomatic morphometric analysis of skeletal muscle obtained by needle biopsy in older adults

Analysis of skeletal muscle mass and composition is essential for studying the biology of age-related sarcopenia, loss of muscle mass, and function. Muscle immunohistochemistry (IHC) allows for simultaneous visualization of morphological characteristics and determination of fiber type composition. The information gleaned from myosin heavy chain (MHC) isoform, and morphological measurements offer a more complete assessment of muscle health and properties than classical techniques such as SDS-PAGE and ATPase immunostaining; however, IHC quantification is a time-consuming and tedious method. We developed a semiautomatic method to account for issues frequently encountered in aging tissue. We analyzed needle-biopsied vastus lateralis (VL) of the quadriceps from a cohort of 14 volunteers aged 74.9 ± 2.2 years. We found a high correlation between manual quantification and semiautomatic analyses for the total number of fibers detected (r² = 0.989) and total fiber cross-sectional area (r² = 0.836). The analysis of the VL fiber subtype composition and the cross-sectional area also did not show statistically significant differences. The semiautomatic approach was completed in 10-15% of the time required for manual quantification. The results from these analyses highlight some of the specific issues which commonly occur in aged muscle. Our methods which address these issues underscore the importance of developing efficient, accurate, and reliable methods for quantitatively analyzing the skeletal muscle and the standardization of collection protocols to maximize the likelihood of preserving tissue quality in older adults. Utilizing IHC as a means of exploring the progression of disease, aging, and injury in the skeletal muscle allows for the practical study of muscle tissue down to the fiber level. By adding editing modules to our semiautomatic approach, we accurately quantified the aging muscle and addressed common technical issues.

Skeletal muscle - A bystander or influencer of metabolic syndrome?

BACKGROUND AND AIMS

Metabolic syndrome is the concurrent presentation of multiple cardiovascular risk factors, including obesity, insulin resistance, hyperglycemia, dyslipidemia and hypertension. It has been suggested that some of these risk factors can have detrimental effects on the skeletal muscle while others can be a direct result of skeletal muscle abnormalities, showing a two-way directionality in the pathogenesis of the condition. This review aims to explore this bidirectional correlation by discussing the impact of metabolic syndrome on skeletal muscle tissue in general and will also discuss ways in which skeletal muscle alterations may contribute to the pathogenesis of metabolic syndrome.

METHODS

Literature searches were conducted with key words (e.g. metabolic syndrome, skeletal muscle, hyperglycemia) using PubMed, EBSCOhost, Science Direct and Google Scholar. All article types were included in the search.

RESULTS

The pathological mechanisms associated with metabolic syndrome, such as hyperglycemia and inflammation, have been associated with changes in skeletal muscle fiber composition, metabolism, insulin sensitivity, mitochondrial function, and strength. Additionally, some skeletal muscle alterations, particularly mitochondrial dysfunction and insulin resistance, are suggested to contribute to the development of metabolic syndrome. For example, the suggested underlying mechanisms of sarcopenia development are also contributors to metabolic syndrome pathogenesis.

CONCLUSION

Whilst numerous studies have identified a relationship between metabolic syndrome and skeletal muscle abnormalities, further investigation into the underlying mechanisms is needed to elucidate the best prevention and management strategies for these conditions.

Prevalence of Osteosarcopenia and Its Association with Cardiovascular Risk Factors in Iranian Older People: Bushehr Elderly Health (BEH) Program

Osteosarcopenia is an increasingly recognized geriatric syndrome with a considerable prevalence which increases morbidity and mortality. Although osteosarcopenia is a result of age-related deterioration in muscle and bone, there are many risk factors that provoking osteosarcopenia. These risk factors should be considered by the clinicians to treat osteosarcopenia. We assessed the link between osteosarcopenia and conventional risk factors of cardiovascular diseases. This study was a cross-sectional study that has been conducted within the framework of Bushehr Elderly Health (BEH) program stage II in which participants aged ≥ 60 years were included. Osteopenia/osteoporosis was defined as a t-score ≤  - 1.0 standard deviation below the mean values of a young healthy adult. We defined sarcopenia as reduced skeletal muscle mass plus low muscle strength and/or low physical performance. Osteosarcopenia was considered as the presence of both osteopenia/osteoporosis and sarcopenia. We estimated the age-standardized prevalence of osteosarcopenia for men and women, separately. Using modified Poisson regression analysis, adjusted prevalence ratio (PR) with 95% CI was used to show the measure of associations in the final model. Among 2353 participants, 1205 (51.2%) were women. Age-standardized prevalence of osteosarcopenia was 33.8 (95% CI 31.0-36.5) in men and 33.9 (30.9-36.8) in women. In both sexes, the inverse association was detected with body mass index and having osteosarcopenia (PR 0.84, 95% CI 0.81-0.88 in men and 0.77, 95% CI 0.74-0.80 in women). In both sexes, high-fat mass was positively associated with osteosarcopenia [PR 1.46 (95% CI 1.11-1.92) in men, and 2.25 (95% CI 1.71-2.95) in women]. Physical activity had a significant inverse association in men (PR = 0.64, 95% CI 0.46, 0.88), but not in women. Diabetes was also showed a direct association with osteosarcopenia in men (PR 1.33, 95% CI 1.04-1.69). No associations were detected between the lipid profiles and osteosarcopenia. Results demonstrated a high prevalence of osteosarcopenia in both sexes suggesting a high disease burden in a rapidly aging country. Lifestyle and socioeconomic factors, as well as chronic diseases, were significantly associated with osteosarcopenia.

Nonalcoholic Fatty Liver Disease and Sarcopenia Are Independently Associated With Cardiovascular Risk

OBJECTIVES

Nonalcoholic fatty liver disease (NAFLD) and sarcopenia have a close association with an increased risk of atherosclerotic cardiovascular disease (ASCVD). This study investigated the influence of NAFLD and sarcopenia on ASCVD risk.

METHODS

Data from the 2008-2011 Korean National Health and Nutrition Examination Surveys database were analyzed (n = 7,191). The sarcopenia index was calculated using dual-energy x-ray absorptiometry. Sarcopenia was defined as the lowest quintile sarcopenia index value (cutoffs = 0.882 for men and 0.582 for women). NAFLD was defined as a comprehensive NAFLD score ≥40. Liver fibrosis was assessed using the fibrosis-4 (FIB-4) index. ASCVD risk was evaluated using American College of Cardiology/American Heart Association guidelines. High probability of ASCVD was defined as ASCVD risk >10%.

RESULTS

The prevalence rates of NAFLD and sarcopenia were 31.2% (n = 2,241) and 19.5% (n = 1,400), respectively. The quartile-stratified ASCVD risk scores were positively associated with NAFLD and sarcopenia (all P for trend < 0.001). Subjects with both NAFLD and sarcopenia had a higher risk for high probability of ASCVD (odds ratio = 1.83, P = 0.014) compared with controls without NAFLD and sarcopenia. Among subjects with NAFLD, FIB-4-defined significant liver fibrosis and sarcopenia additively raised the risk for high probability of ASCVD (odds ratio = 3.56, P < 0.001) compared with controls without FIB-4-defined significant liver fibrosis or sarcopenia.

DISCUSSION

NAFLD and sarcopenia were significantly associated with an increased risk of ASCVD in the general population. In addition, NAFLD with significant liver fibrosis and sarcopenia were significantly associated with an increased risk of ASCVD in subjects with NAFLD.

Sarcopenia-related traits and coronary artery disease: a bi-directional Mendelian randomization study

Previous Mendelian randomization (MR) studies have yielded a conflicting causal relationship between sarcopenia and coronary artery disease (CAD), and lack the association of CAD with sarcopenia. We performed a bi-directional MR approach to clarify the causality and causal direction between sarcopenia-related traits and CAD. In stage 1 analysis, estimates of inverse variance weighting (IVW) and several sensitivity analyses were obtained by applying genetic variants that predict sarcopenia-related traits to CAD. Conversely, we also applied genetic variants that predict CAD to sarcopenia-related traits in stage 2 analyses. IVW analysis showed that higher handgrip strength reduces risk for CAD: A 1-kilogram (kg) increase in genetically determined left handgrip strength reduced odds of CAD by 36% [odds ratio (OR) = 0.64, 95% confidence interval (CI) 0.498 - 0.821, p = 4.56E-04], and right handgrip strength reduced odds of CAD by 41.1% (OR = 0.599, 95% CI 0.476 - 0.753, p = 1.10E-05). However, genetically predicted CAD did not show any causal association with handgrip strength, and no significant causal relationship was detected between genetically instrumented body lean mass and CAD. Our results suggest that decreased muscle strength but not decreased muscle mass leads to the increased risk of CAD in sarcopenia.

A cross-sectional study: Associations between sarcopenia and clinical characteristics of patients with type 2 diabetes

Sarcopenia is a geriatric syndrome and it impairs physical function. Patients with type 2 diabetes mellitus (T2DM) are at a higher risk of sarcopenia. The purpose of this study is to explore characteristics of general information and metabolic factors of sarcopenia in patients with T2DM in the northeast of China, and provide information for the prevention and treatment of sarcopenia in clinical practice.Patients with T2DM aged ≥65 were recruited in Changchun from March 2017 to February 2018. Questionnaires of general information, physical examination, laboratory and imaging examination were conducted. The patients were assigned into sarcopenia group and non-sarcopenia group according to the diagnostic criteria proposed by Asian working group for sarcopenia (AWGS), and the differences between 2 groups were analyzed.A total of 132 participants were included in this study, of which, 38 (28.8%) were diagnosed with sarcopenia. 94 (71.2%) were with no sarcopenia. Logistic regression analysis showed that age (OR: 1.182, 95%CI: 1.038-1.346), trunk fat mass (TFM) (OR: 1.499, 95%CI: 1.146-1.960) and free thyroxine (FT4) (OR: 1.342, 95%CI: 1.102-1.635) were independent risk factors for sarcopenia. BMI (body mass index) (OR: 0.365, 95%CI: 0.236-0.661), exercise (OR: 0.016, 95%CI: 0.001-0.169), female (OR: 0.000, 95%CI: 0.00-0.012), metformin (OR: 0.159, 95%CI: 0.026-0.967) and TSM (trunk skeletal muscle mass) (OR: 0.395, 95%CI: 0.236-0.661) were protective factors for sarcopenia.Sarcopenia in patients with T2DM is associated with increased age, increased TFM and increased FT4 level. Regular exercise, female, metformin administrations, high BMI and increased TSM are associated with lower risk of sarcopenia.

Health Consequences of Sarcopenic Obesity: A Narrative Review

Sarcopenia is defined as the age-related loss of muscle mass and strength or physical performance. Increased amounts of adipose tissue often accompany sarcopenia, a condition referred to as sarcopenic obesity. The prevalence of sarcopenic obesity among adults is rapidly increasing worldwide. However, the lack of a universal definition of sarcopenia limits comparisons between studies. Sarcopenia and obesity have similar pathophysiologic factors, including lifestyle behaviors, hormones, and immunological factors, all of which may synergistically affect the risk of developing a series of adverse health issues. Increasing evidence has shown that sarcopenic obesity is associated with accelerated functional decline and increased risks of cardiometabolic diseases and mortality. Therefore, the identification of sarcopenic obesity may be critical for clinicians in aging societies. In this review, we discuss the effect of sarcopenic obesity on multiple health outcomes and its role as a predictor of these outcomes based on the components of sarcopenia, including muscle mass, muscle strength, and physical performance.

Fat-free mass and glucose homeostasis: is greater fat-free mass an independent predictor of insulin resistance?

BACKGROUND

A greater fat-free mass (FFM) is purported to be associated with protective effects on insulin resistance (IR). However, recent studies suggested negative associations between FFM and IR.

OBJECTIVES

(1) To explore the direction of the association between FFM and IR in a large heterogeneous sample after controlling for confounding factors. (2) To determine cut off values of FFM associated with an increased risk of IR.

METHODS

Outcome variables were measured in 7044 individuals (48.6% women, 20-79 years; NHANES, 1999-2006): body composition [fat mass (FM), FFM and appendicular FFM (aFFM); DXA], FFM index [FFMI: FFM/height (kg/m²)], appendicular FFMI [aFFM/height (kg/m²)] and insulin resistance (HOMA-IR). Multivariate regression analyses were performed to determine the independent predictors of HOMA-IR in younger (20-49 years) and older (50-79 years) men and women. ROC analyses were used to determine FFM cut-offs to identify a higher risk of insulin resistance (HOMA-IR > 75th percentile).

RESULTS

aFFMI was an independent predictor of IR in younger (men: β = 0.21; women: β = 0.31; all p ≤ 0.001) and older (men: β = 0.11; women: β = 0.37; all p ≤ 0.001) individuals. Thresholds for aFFMI at which the risk of IR was significantly increased were 8.96 and 8.39 kg/m² in younger and older men, and 7.22 and 6.64 kg/m² in younger and older women, respectively.

CONCLUSION

Independently of age, a greater aFFMI was an independent predictor of IR. These results suggest revisiting how we envision the link between FFM and IR and explore potential mechanisms.

Association Between Self-Reported Sleep Duration and Body Composition in Middle-Aged and Older Adults

STUDY OBJECTIVES

The current study sought to examine whether self-reported sleep duration is linked to an adverse body composition in 19,709 adults aged 45 to 75 years.

METHODS

All variables used in the current study were derived from the Swedish EpiHealth cohort study. Habitual sleep duration was measured by questionnaires. Body composition was assessed by bioimpedance. The main outcome variables were fat mass and fat-free mass (in kg). Analysis of covariance adjusting for age, sex, fat mass in the case of fat-free mass (and vice versa), leisure time physical activity, smoking, and alcohol consumption was used to investigate the association between sleep duration and body composition.

RESULTS

Short sleep (defined as ≤ 5 hours sleep per day) and long sleep (defined as 8 or more hours of sleep per day) were associated with lower fat-free mass and higher fat mass, compared with 6 to 7 hours of sleep duration (P < .05).

CONCLUSIONS

These observations could suggest that both habitual short and long sleep may contribute to two common clinical phenotypes in middle-aged and older humans, ie, body adiposity and sarcopenia. However, the observational nature of our study does not allow for causal interpretation.

Association of appendicular skeletal muscle mass with carotid intima-media thickness according to body mass index in Korean adults

OBJECTIVES

The combined effects of obesity and appendicular skeletal muscle (ASM) on atherosclerosis, especially in middleaged populations, remain poorly understood. This cross-sectional study investigated the effects of ASM on carotid intima-media thickness (IMT) according to body mass index (BMI) in middle-aged Korean adults.

METHODS

Herein, 595 men and 1,274 women aged 30-64 years completed questionnaires and underwent health examinations as part of the Cardiovascular and Metabolic Disease Etiology Research Center cohort. ASM was measured via bioelectrical impedance analysis and adjusted for weight (ASM/Wt). IMT was assessed using B-mode ultrasonography; highest quartile of IMT was defined as gender-specific top quartile of the IMT values. Higher BMIs was defined as a BMI over 25.0 kg/m2 .

RESULTS

Compared to the highest ASM/Wt quartile, the lowest ASM/Wt quartile was significantly associated with highest quartile of IMT in men with lower BMIs (adjusted odds ratio [aOR], 2.78; 95% confidence interval [CI], 1.09 to 7.13), but not in those with higher BMIs (aOR, 0.59; 95% CI, 0.24 to 1.91). In women, there was no significant association of low skeletal muscle mass with highest quartile of IMT, regardless of BMI.

CONCLUSIONS

Low appendicular skeletal muscle mass is associated with carotid arterial wall thickening in men with lower BMIs, but not in men with higher BMIs. Our findings suggest that the risk of atherosclerosis may be low in middle-aged Korean men with appropriate body weight and skeletal muscle mass maintenance.

Associations between Sarcopenia and Metabolic Risk Factors: A Systematic Review and Meta-Analysis

Background

Metabolic risk factors can impact sarcopenia, but the direct relationship of metabolic risk factors with sarcopenia has not been examined. Our purpose was to investigate the effects of metabolic risk factors on sarcopenia in older adults.

Methods

Sixteen studies were found through a search of electronic databases and were subjected to a meta-analysis to investigate the differences in metabolic risk factors between patients with sarcopenia and controls. The random-effects standardized mean difference ±95% confidence interval was calculated as the effect size.

Results

The results showed that body mass index (BMI), fasting glucose, systolic blood pressure (SBP), diastolic blood pressure (DBP), triglycerides (TG), homeostasis model assessment of insulin resistance (HOMA-IR), high-density lipoprotein cholesterol (HDL-C), and total cholesterol (d=3.252, d=2.039, d=2.956, d=2.579, d=2.123, d=1.195, d=−0.991, and d=1.007, respectively) all had relationships with sarcopenia. In addition, the effect sizes of all male groups for all variables were higher than those of the female groups. However, only the between-sex effect size of HOMA-IR (P<0.01) was significant, while those for BMI, fasting glucose, SBP, DBP, TG, HDL-C, low-density lipoprotein cholesterol, and total cholesterol were not. Finally, the metabolic risk factors appeared to be significantly related to loss of skeletal muscle.

Conclusion

Nutrition and appropriate exercise to enhance muscle strength and quality in the elderly reduce the occurrence of sarcopenia, thereby reducing the incidence of metabolic diseases.

Sarcopenic obesity in older adults: aetiology, epidemiology and treatment strategies

The prevalence of obesity in combination with sarcopenia (the age-related loss of muscle mass and strength or physical function) is increasing in adults aged 65 years and older. A major subset of adults over the age of 65 is now classified as having sarcopenic obesity, a high-risk geriatric syndrome predominantly observed in an ageing population that is at risk of synergistic complications from both sarcopenia and obesity. This Review discusses pathways and mechanisms leading to muscle impairment in older adults with obesity. We explore sex-specific hormonal changes, inflammatory pathways and myocellular mechanisms leading to the development of sarcopenic obesity. We discuss the evolution, controversies and challenges in defining sarcopenic obesity and present current body composition modalities used to assess this condition. Epidemiological surveys form the basis of defining its prevalence and consequences beyond comorbidity and mortality. Current treatment strategies, and the evidence supporting them, are outlined, with a focus on calorie restriction, protein supplementation and aerobic and resistance exercises. We also describe weight loss-induced complications in patients with sarcopenic obesity that are relevant to clinical management. Finally, we review novel and potential future therapies including testosterone, selective androgen receptor modulators, myostatin inhibitors, ghrelin analogues, vitamin K and mesenchymal stem cell therapy.

Sarcopenic obesity assessed using dual energy X-ray absorptiometry (DXA) can predict cardiovascular disease in patients with type 2 diabetes: a retrospective observational study

Background

Sarcopenic obesity, defined as reduced skeletal muscle mass and power with increased adiposity, was reported to be associated with cardiovascular disease risks in previous cross-sectional studies. Whole body dual-energy X-ray absorptiometry (DXA) can simultaneously evaluate both fat and muscle mass, therefore, whole body DXA may be suitable for the diagnosis of sarcopenic obesity. However, little is known regarding whether sarcopenic obesity determined using whole body DXA could predict incident cardiovascular disease (CVD). The aim of this study was to investigate the impact of sarcopenic obesity on incident CVD in patients with type 2 diabetes.

Methods

A total of 716 Japanese patients (mean age 65 ± 13 years; 47.0% female) were enrolled. Android fat mass (kg), gynoid fat mass (kg), and skeletal muscle index (SMI) calculated as appendicular non-fat mass (kg) divided by height squared (m²), were measured using whole body DXA. Sarcopenic obesity was defined as the coexistence of low SMI and obesity determined by four patterns of obesity as follows: android to gynoid ratio (A/G ratio), android fat mass or percentage of body fat (%BF) was higher than the sex-specific median, or body mass index (BMI) was equal to or greater than 25 kg/m². The study endpoint was the first occurrence or recurrence of CVD.

Results

Over a median follow up of 2.6 years (IQR 2.1–3.2 years), 53 patients reached the endpoint. Sarcopenic obesity was significantly associated with incident CVD even after adjustment for the confounding variables, when using A/G ratio [hazard ratio (HR) 2.63, 95% CI 1.10–6.28, p = 0.030] and android fat mass (HR 2.57, 95% CI 1.01–6.54, p = 0.048) to define obesity, but not %BF (HR 1.67, 95% CI 0.69–4.02, p = 0.252), and BMI (HR 1.55, 95% CI 0.44–5.49, p = 0.496).

Conclusions

The present data suggest that the whole body DXA is valuable in the diagnosis of sarcopenic obesity (high A/G ratio or android fat mass with low SMI) to determine the risk of CVD events in patients with type 2 diabetes. Meanwhile, sarcopenic obesity classified with low SMI, and high %BF or BMI was not associated with incident CVD.

Electronic supplementary material

The online version of this article (10.1186/s12933-018-0700-5) contains supplementary material, which is available to authorized users.

Associations of sarcopenic obesity with the metabolic syndrome and insulin resistance over five years in older men: The Concord Health and Ageing in Men Project

PURPOSE

Previous cross-sectional studies investigating associations of sarcopenic obesity with metabolic syndrome (MetS) and insulin resistance have not utilised consensus definitions of sarcopenia. We aimed to determine associations of sarcopenic obesity with MetS and insulin resistance over five years in community-dwelling older men.

METHODS

1231 men aged ≥70 years had appendicular lean mass (ALM) and body fat percentage assessed by dual-energy X-ray absorptiometry and hand grip strength and gait speed tests. Sarcopenia was defined as low ALM/height (m²) and low hand grip strength or gait speed (European Working Group definition); obesity was defined as body fat percentage ≥30%. MetS was assessed at baseline and 5-years later. Homeostasis Model Assessment of Insulin Resistance (HOMA-IR) was assessed at 5-years only.

RESULTS

Men with sarcopenic obesity (odds ratio, 95% CI: 2.07, 1.21-3.55) and non-sarcopenic obesity (4.19, 3.16-5.57) had higher MetS likelihood than those with non-sarcopenic non-obesity at baseline. Higher gait speed predicted lower odds for prevalent MetS (0.45, 0.21-0.96 per m/s). Higher body fat predicted increased odds for prevalent and incident MetS (1.14, 1.11-1.17 and 1.11, 1.02-1.20 per kg, respectively) and deleterious 5-year changes in MetS fasting glucose, high-density lipoprotein cholesterol and triglycerides (all P < 0.05). Compared with non-sarcopenic non-obesity, estimated marginal means for HOMA-IR at 5-years were higher in non-sarcopenic obesity only (1.0, 0.8-1.1 vs 1.3, 1.2-1.5; P < 0.001). Similar results were observed when sarcopenic obesity was defined by waist circumference.

CONCLUSIONS

Sarcopenic obesity does not appear to confer greater risk for incident MetS or insulin resistance than obesity alone in community-dwelling older men.

Analysis of relationship of high fat mass and low muscle mass with lipid profile in Brazilians aged 80 years or over

AIM

To analyze the lipid profile of older people aged ≥80 years according to body composition (high fat mass, low muscle mass and both).

MATERIAL AND METHOD

The sample consisted of 113 older people aged ≥80 years. The assessment of body composition was made using Dual Energy X-ray Absorptiometry (DXA) and the lipid profile analysis using an enzymatic colorimetric kit. We used Analysis of Variance (ANOVA) test to compare the mean of lipid profile according to body composition and were constructed logistic regression models to verify the association between these two variables.

RESULTS

It was found that older people with high fat had higher mean values of TG compared to normal and low muscle mass group. Older people with low muscle mass showed mean values of LDL-c lower than other groups. It was observed that older people with high fat is more likely to have (OR 2.70; 95%CI 1.14-6.37) high blood concentration of TG.

CONCLUSION

Thus, it appears that high fat is related to the high blood concentration of TG in older people aged ≥80 years, especially those with Asian origin and diabetes besides those with low muscle mass shows lower mean values of LDL-c.

The increased risk of sarcopenia in patients with cardiovascular risk factors in Suburb-Dwelling older Chinese using the AWGS definition

The aim of the present study is to investigate the relationship between sarcopenia and cardiovascular risk factors (CVRF) in the Chinese elderly. A total of 1611 elderly individuals aged ≥60 years were enrolled in this study. The well-established CVRF of diabetes, hypertensions, and dyslipidemia were assessed. Sarcopenia was defined according to the recommended algorithm of the Asian Working Group for Sarcopenia (AWGS). Multiple logistic regression analyses and the linear regressions were used to evaluate the components of CVRF and the number of CVRF of elderly patients with sarcopenia. After adjusting for potential confounders, CVRF was associated with a high prevalence of sarcopenia in elderly Chinese populations. Furthermore, diabetes and hypertension, but not dyslipidemia, were found to be significantly associated with sarcopenia. The OR and 95% CI for sarcopenia of the participants with 1, 2, and 3 features of CVRF were 2.27(1.14-4.48), 4.13(1.80-9.46), and 4.90(1.01-23.81), respectively. A linear increase in the prevalence of sarcopenia was found to be associated with the number of CVRF components in the elderly population (P values for the trends < 0.001). Knowledge of known CVRF, particularly diabetes and hypertension, may help predict the risk for sarcopenia in the elderly.

Hypothalamic Dysfunction and Multiple Sclerosis: Implications for Fatigue and Weight Dysregulation

Signs and symptoms of multiple sclerosis are usually attributed to demyelinating lesions in the spinal cord or cerebral cortex. The hypothalamus is a region that is often overlooked yet controls many important homeostatic functions, including those that are perturbed in multiple sclerosis. In this review we discuss how hypothalamic dysfunction may contribute to signs and symptoms in people with multiple sclerosis. While dysfunction of the hypothalamic-pituitary-adrenal axis is common in multiple sclerosis, the effects and mechanisms of this dysfunction are not well understood. We discuss three hypothalamic mechanisms of fatigue in multiple sclerosis: (1) general hypothalamic-pituitary-adrenal axis hyperactivity, (2) disordered orexin neurotransmission, (3) abnormal cortisol secretion. We then review potential mechanisms of weight dysregulation caused by hypothalamic dysfunction. Lastly, we propose future studies and therapeutics to better understand and treat hypothalamic dysfunction in multiple sclerosis. Hypothalamic dysfunction appears to be common in multiple sclerosis, yet current studies are underpowered and contradictory. Future studies should contain larger sample sizes and standardize hormone and neuropeptide measurements.

Comparisons of three different methods for defining sarcopenia: An aspect of cardiometabolic risk

Appraisal of muscle mass is important when considering the serious consequences of sarcopenia in an aging society. However, the associations between sarcopenia and its clinical outcomes might vary according to the method applied in its diagnosis. We compared the relationships between cardiometabolic risk parameters and sarcopenia defined according to three different diagnostic methods using dual-energy X-ray absorptiometry (DXA) and computed tomography (CT). Appendicular skeletal muscle mass (ASM) adjusted by height squared and BMI (ASM/height² and ASM/BMI) measured using DXA and thigh muscle cross-sectional area (tmCSA) adjusted by weight (tmCSA/weight) measured using CT were used as indices of muscle mass. Sarcopenia was defined as two standard deviations below either the mean ASM/height², ASM/BMI, or tmCSA/weight of a young reference group. ASM/BMI and tmCSA/weight showed a negative relationship with several components of metabolic syndrome and HOMA-IR, whereas ASM/height² was positively associated with theses cardiometabolic risk factors. Logistic regression analyses demonstrated that ASM/BMI-defined sarcopenia was significantly associated with increased HOMA-IR (P = 0.01) and prevalence of visceral obesity (P = 0.03) and metabolic syndrome (P = 0.025), while ASM/height²- and tmCSA/weight-defined sarcopenia were not. ASM/BMI-defined sarcopenia exhibits a closer relationship with cardiometabolic risk factors than does ASM/height²- or tmCSA/weight-defined sarcopenia.

Prevalence of sarcopenia and sarcopenic obesity in older German men using recognized definitions: high accordance but low overlap!

The relevance of sarcopenia and sarcopenic Obesity (SO) is rising in our aging societies. Applying recognized definitions to 965 community-dwelling Bavarian men 70 years+ resulted in a prevalence for sarcopenia between 3.7 and 4.9 and between 2.1 and 4.1% for SO. Despite this high consistency, the overlap between the definitions/approaches was <50%.

INTRODUCTION

The relevance of sarcopenia and sarcopenic obesity (SO) is rising steadily in the aging societies of most developed nations. However, different definitions, components, and cutoff points hinder the evaluation of the prevalence of sarcopenia and SO. The purpose of this contribution was to determine the prevalence of sarcopenia and SO in a cohort of community-dwelling German men 70+ applying established sarcopenia (European Working Group on Sarcopenia in Older People, Foundation National Institute of Health, International Working Group on Sarcopenia) and obesity definitions. Further, we addressed the overlap between the definitions.

METHODS

Altogether, 965 community-dwelling men 70 years and older living in Northern Bavaria, Germany, were assessed during the screening phase of the Franconian Sarcopenic Obesity project. Segmental multi-frequency bio-impedance analysis (BIA) was applied to determine weight and body composition.

RESULTS

Applying the definitions of EWGSOP, IWGS, and FNIH, 4.9, 3.8, and 3.7% of the total cohort were classified as sarcopenic, respectively. When further applying body fat to diagnose obesity, SO prevalence in the total cohort ranged from 4.1% (EWGSOP + body fat >25%) to 2.1% (IWGS + body fat >30%). Despite the apparently high consistency of the approaches with respect to prevalence, the overlap in individual sarcopenia diagnosis between the sarcopenia definitions was rather low (<50%).

CONCLUSION

The prevalence of sarcopenia and SO in community-dwelling German men 70 years+ is relatively low (<5%) independently of the definition used. However, consistency of individual sarcopenia diagnosis varies considerably between the three definitions. Since sarcopenia is now recognized as an independent condition by the International Classification of Diseases, a mandatory definition must be stated.

TRIAL REGISTRATION NUMBER

ClinicalTrials.gov: NCT2857660.

Association between ratio indexes of body composition phenotypes and metabolic risk in Italian adults

The ratio between fat mass (FM) and fat-free mass (FFM) has been used to discriminate individual differences in body composition and improve prediction of metabolic risk. Here, we evaluated whether the use of a visceral adipose tissue-to-fat-free mass index (VAT:FFMI) ratio was a better predictor of metabolic risk than a fat mass index to fat-free mass index (FMI:FFMI) ratio. This is a cross-sectional study including 3441 adult participants (age range 18-81; men/women: 977/2464). FM and FFM were measured by bioelectrical impedance analysis and VAT by ultrasonography. A continuous metabolic risk Z score and harmonised international criteria were used to define cumulative metabolic risk and metabolic syndrome (MetS), respectively. Multivariate logistic and linear regression models were used to test associations between body composition indexes and metabolic risk. In unadjusted models, VAT:FFMI was a better predictor of MetS (OR 8.03, 95%CI 6.69-9.65) compared to FMI:FFMI (OR 2.91, 95%CI 2.45-3.46). However, the strength of association of VAT:FFMI and FMI:FFMI became comparable when models were adjusted for age, gender, clinical and sociodemographic factors (OR 4.06, 95%CI 3.31-4.97; OR 4.25, 95%CI 3.42-5.27, respectively). A similar pattern was observed for the association of the two indexes with the metabolic risk Z score (VAT:FFMI: unadjusted b = 0.69 ± 0.03, adjusted b = 0.36 ± 0.03; FMI:FFMI: unadjusted b = 0.28 ± 0.028, adjusted b = 0.38 ± 0.02). Our results suggest that there is no real advantage in using either VAT:FFMI or FMI:FFMI ratios as a predictor of metabolic risk in adults. However, these results warrant confirmation in longitudinal studies.

Dynapenia and Metabolic Health in Obese and Nonobese Adults Aged 70 Years and Older: The LIFE Study

OBJECTIVE

The purpose of this study was to examine the relationship between dynapenia and metabolic risk factors in obese and nonobese older adults.

METHODS

A total of 1453 men and women (age ≥70 years) from the Lifestyle Interventions and Independence for Elders (LIFE) Study were categorized as (1) nondynapenic/nonobese (NDYN-NO), (2) dynapenic/nonobese (DYN-NO), (3) nondynapenic/obese (NDYN-O), or (4) dynapenic/obese (DYN-O), based on muscle strength (Foundation for the National Institute of Health criteria) and body mass index. Dependent variables were blood lipids, fasting glucose, blood pressure, presence of at least 3 metabolic syndrome (MetS) criteria, and other chronic conditions.

RESULTS

A significantly higher likelihood of having abdominal obesity criteria in NDYN-NO compared with DYN-NO groups (55.6 vs 45.1%, P ≤ .01) was observed. Waist circumference also was significantly higher in obese groups (DYN-O = 114.0 ± 12.9 and NDYN-O = 111.2 ± 13.1) than in nonobese (NDYN-NO = 93.1 ± 10.7 and DYN-NO = 92.2 ± 11.2, P ≤ .01); and higher in NDYN-O compared with DYN-O (P = .008). Additionally, NDYN-O demonstrated higher diastolic blood pressure compared with DYN-O (70.9 ± 10.1 vs 67.7 ± 9.7, P ≤ .001). No significant differences were found across dynapenia and obesity status for all other metabolic components (P > .05). The odds of having MetS or its individual components were similar in obese and nonobese, combined or not with dynapenia (nonsignificant odds ratio [95% confidence interval]).

CONCLUSION

Nonobese dynapenic older adults had fewer metabolic disease risk factors than nonobese and nondynapenic older adults. Moreover, among obese older adults, dynapenia was associated with lower risk of meeting MetS criteria for waist circumference and diastolic blood pressure. Additionally, the presence of dynapenia did not increase cardiometabolic disease risk in either obese or nonobese older adults.

The development of the metabolic syndrome and insulin resistance after adjuvant treatment for breast cancer

BACKGROUND

Adjuvant breast cancer treatment is associated with a number of adverse physical changes, including weight gain, and therefore may represent a critical period for the development of metabolic disturbance.

OBJECTIVE

The aim of this study was to evaluate changes in the presentation of the metabolic syndrome (MetSyn) and insulin resistance from breast cancer surgery to postcompletion of adjuvant treatment.

METHODS

Sixty-one participants who had completed metabolic screening, including fasting blood samples and anthropometric measurements, on the morning of breast cancer surgery were recruited. Measures were repeated after completion of adjuvant treatment. Change in the proportion of participants presenting with the MetSyn was evaluated using the related-samples McNemar test, and changes in measures of glucose metabolism (fasting insulin, insulin resistance [homeostatic model assessment index], and glycosylated hemoglobin [HbA1c]) were analyzed using paired t tests. The Kruskal-Wallis test was used to compare differences in changes in metabolic parameters across clinical and lifestyle characteristics.

RESULTS

There was a significant (P < .001) increase in fasting insulin (mean [SE] change, 2.73 [0.57] mU/L), homeostatic model assessment index (0.58 [0.14]), and HbA1c level (4.49 [5.63] mmol/mol) from baseline to follow-up along with an increase in the proportion diagnosed with the MetSyn (P = .03). Those with the MetSyn at diagnosis experienced a greater increase in insulin resistance. Premenopausal women experienced greatest increases in HbA1c level.

CONCLUSIONS

Results demonstrate the development of significant metabolic dysfunction, characterized by glucose dysmetabolism and MetSyn, after adjuvant treatment for breast cancer.

IMPLICATIONS FOR PRACTICE

Interventions to improve the metabolic profile of breast cancer survivors are warranted.