Height-adjusted Appendicular Skeletal Muscle Mass Research Articles

Appendicular Skeletal Muscle Mass Associated with Sarcopenia as a Predictor of Poor Functional Outcomes in Ischemic Stroke.

Several studies have examined the clinical impact of poststroke and stroke-related sarcopenia on stroke recovery. However, few studies have investigated the effect of sarcopenia detected shortly after stroke on functional prognosis. We predicted functional outcomes using early screening for sarcopenia in patients with acute ischemic stroke. We also examined the effect of sarcopenia detected shortly after stroke on functional prognosis. Patients diagnosed with acute ischemic stroke within 2 days of symptom onset were consecutively enrolled at a tertiary university hospital. Appendicular skeletal muscle mass (ASM) was measured using dual-energy X-ray absorptiometry during early hospitalization. Sarcopenia was diagnosed based on low ASM and strength criteria of the Asian Working Group for Sarcopenia (AWGS) and European Working Group on Sarcopenia in Older People (EWGSOP2). The primary outcome was poor functional outcome, defined as a modified Rankin score of 4-6 and all-cause mortality at 3 months. Of the 653 patients, 214 (32.8%) and 174 (26.6%) had sarcopenia according to the AWGS and EWGSOP2 criteria, respectively. Irrespective of the definition, the sarcopenia group had a significantly higher proportion of patients with poor functional outcomes and all-cause mortality. Multivariate logistic regression analysis revealed that height-adjusted ASM was independently associated with poor functional outcomes (odds ratio: 0.61; 95% confidence interval: 0.40-0.91; P <0.005), and they were negatively correlated. However, the association between 3-month mortality, skeletal muscle mass, and sarcopenia was not sustained in multivariate analyses. Height-adjusted ASM associated with sarcopenia is a potential predictor of poor functional outcomes at 3 months in patients with acute stroke. However, owing to the limitations of this study, further research is required to confirm these findings.

Myopenic Obesity Determined by Fat Mass Percentage Predicts Risk of Aspirin-Induced Bleeding in Chinese Older Adults.

Body mass index (BMI) correlates with aspirin-induced bleeding risk. However, skeletal muscle mass (SMM) loss and fat gain commonly occur with aging, making BMI not a reasonable marker of bleeding risk in older individuals. In the present study, we aimed to investigate the prognostic value of myopenic obesity based on the percent of fat mass (%FM) for aspirin-induced bleeding in Chinese patients over 60 years old. We prospectively analyzed 185 patients taking aspirin for primary and secondary prevention of cardiovascular diseases. Body composition parameters were estimated using bioelectrical impedance analysis. We defined myopenic obesity (MO) as a height-adjusted appendicular SMM <7.0 kg/m2 in males and <5.7 kg/m2 in females with a %FM >29% in males and >41% in females or a BMI ≥25 kg/m2. The patients were categorized into four groups by the presence or absence of myopenia and obesity. Based on the %FM grouping, the bleeding risk was significantly higher in the MO group, followed by the nonmyopenic obesity, myopenic nonobesity, and nonmyopenic nonobesity groups (P = 0.044). No statistically significant differences in the probability of bleeding events were observed among the four BMI-based groups (P = 0.502). Multivariate Cox analysis indicated that MO (hazard ratio [HR] 2.724, 95% confidence interval [CI] 1.073-6.918, P = 0.035), aspirin dose (100 vs 50 mg/day, HR 2.609, 95% CI 1.291-5.273, P = 0.008), concomitant use of histamine-2 receptor antagonists and proton pump inhibitors (HR 1.777, 95% CI 1.007-3.137, P = 0.047), and hemorrhage history (HR 2.576, 95% CI 1.355-4.897, P = 0.004) were associated with bleeding events independently. %FM-based MO was an independent predictor of aspirin-induced bleeding in older Chinese individuals. Reducing %FM rather than BMI should be an optimal strategy for the management of myopenic obesity.

Hemoglobin level is negatively associated with sarcopenia and its components in Chinese aged 60 and above.

Sarcopenia and low hemoglobin level are common in older adults. Few studies have evaluated the association between hemoglobin level and sarcopenia and with inconsistent findings. The multifaceted effects of sarcopenia on the human body and the high prevalence of anemia in the Chinese population make it necessary to explore the association between the two. Using the China Health and Retirement Longitudinal Study (CHARLS), we explored the association between hemoglobin with sarcopenia and its components in the Chinese population aged 60 and above. Multivariate logistic and Cox proportional hazards models were constructed to examine the association of hemoglobin level with sarcopenia and sarcopenia components in individuals aged 60 years or above. The subgroup analysis covered residence, body mass index level, drinking status, and smoking status were conducted. The possible difference of associations between sexes was also explored. With a total of 3,055 people, the hemoglobin concentration in people without sarcopenia, possible sarcopenia, and sarcopenia are 14.34 ± 2.22, 14.64 ± 2.27, and 13.58 ± 2.02 g/dl, respectively. Cross-sectional analysis showed strong evidence that hemoglobin was negatively associated with sarcopenia [Odds Ratio (OR) = 0.95, 95% Confidence Interval (CI): 0.90-0.99] and low height-adjusted appendicular skeletal muscle mass (OR = 0.91, 95% CI: 0.86-0.97). On average, a per 1 g/dl higher hemoglobin level was associated with 5% lower odds of sarcopenia (OR = 0.95, 95% CI: 0.90-0.98). The cohort study of 1,022 people demonstrated a statistically significant negative association of hemoglobin level with low physical performance [Hazard Ratio (HR) = 0.92, 95% CI: 0.85-0.99], merely with sarcopenia (HR = 0.92, 95% CI: 0.84-1.00) and skeletal muscle mass (HR = 0.95, 95% CI: 0.80-1.00). Sex-specific analysis suggested hemoglobin's association with sarcopenia, muscle mass, and physical performance in all sexes, with weaker magnitudes in females. Hemoglobin in urban residents and people with high body mass index (BMI) has a larger magnitude of the negative association with sarcopenia. Hemoglobin level associates with sarcopenia, muscle mass, and physical performance in the Chinese population aged 60 and above, with sex-specific, residence-specific, and BMI-specific effects.

Presence of sarcopenia identifies a special group of lean NAFLD in middle-aged and older people.

Sarcopenia, the age-related loss of muscle mass and function, is closely associated and frequently concomitant with non-alcoholic fatty liver disease (NAFLD). We aimed to investigate the clinical features of the sarcopenic NAFLD patients from middle-aged and older people. A total of 1305 patients with NAFLD from the Shanghai Changfeng Study were included for analysis. Sarcopenia was diagnosed based on the height-adjusted appendicular skeletal muscle mass (ASM/height2). We comprehensively analyzed the metabolic phenotype, carotid artery condition, liver fibrosis score, and serum metabolomic profile of each participant. Among the middle-aged and older population, 68.1% of patients with sarcopenia and NAFLD were lean. Sarcopenia was independently associated with increased risk of carotid plaque (OR, 2.22; 95%CI 1.23-4.02) and liver fibrosis (OR, 2.07; 95%CI 1.24-3.44), and the sarcopenic lean NAFLD patients were characterized by a higher risk of carotid plaque (p = 0.008) and liver fibrosis (p = 0.001) than the non-sarcopenic lean NAFLD patients, despite their lower BMI and similar prevalence of metabolic syndrome and diabetes. Further serum metabolomic examination indicated that the sarcopenic lean NAFLD patients presented a distinct metabolomic profile prone to carotid plaque and liver fibrosis, with upregulated serum valine, N-acetylneuraminyl-glycoproteins, lactic acid, small LDL triglycerides and VLDL5 components, and reduced components of HDL4. A sarcopenic characterization score based on above metabolites was established and could also predict increased risk of carotid plaque and liver fibrosis. The presence of sarcopenia identifies a special subgroup of lean NAFLD with increased risk of cardiovascular disease and liver fibrosis clinically.

Quantitative computed tomography-based evaluation of skeletal muscle and presence of sarcopenia in patients with chronic obstructive pulmonary disease.

Sarcopenia, or age-related muscle loss, is a common comorbidity in patients with chronic obstructive pulmonary disease (COPD) with multiple contributing factors. We hypothesized that the presence of sarcopenia can be estimated using quantitative computed tomography-based parameters in patients with COPD. We retrospectively evaluated 38 elderly (≥65 years) men with COPD for pooled data, including hand grip strength and gait speed. Sarcopenia was diagnosed based on the updated 2019 criteria set by the Asian Working Group for Sarcopenia. Cross-sectional area of the erector spinae muscle (ESM) and pectoralis muscle (PM) were quantitatively evaluated and adjusted by height (ESM-I, and PM-I). Sarcopenia was diagnosed in 11 (29%) patients. The mean ESM-I and PM-I were 11.0 and 9.5cm2/m2, respectively, and significantly correlated with height-adjusted appendicular skeletal muscle mass. The optimal cutoff ESM-I for the presence of sarcopenia was 9.41cm2/m2. ESM loss helped estimate sarcopenia in patients with COPD.

Effects of nutritional supplement and resistance training for sarcopenia in patients with inflammatory bowel disease: A randomized controlled trial.

Background:Nutritional supplementation and resistance training are broadly recommended as part of the treatment of sarcopenia, but studies that have evaluated interventions in inflammatory bowel disease patients with sarcopenia are lacking. The aim of this study was to evaluate the effects of nutritional supplementation and resistance training for improving height-adjusted appendicular skeletal muscle mass (ASM/H2) and medical indices in patients with inflammatory bowel disease.Methods:This randomized, double-blind, placebo-controlled trial of forty-five participants was performed at Huadong Hospital Affiliated to Fudan University in Shanghai from September 2020 to June 2021. Eligible participants were randomly assigned to receive whey protein (10 g/d) or placebo (10 g/d) for 8 weeks while completing a resistance training program (3 times a week). Data such as ASM/H2 and other medical indices were collected at baseline and at 4 and 8 weeks of intervention.Results:Fifteen participants were allocated to the resistance training and whey protein (RT+WP) group, and thirteen participants were allocated to the resistance training and placebo (RT+placebo) group. The ASM/H2 significantly increased in the RT+WP group after 4 and 8 weeks of intervention, and the ASM/H2 of the RT+WP group was significantly higher than that of the RT+placebo group after 4 and 8 weeks of intervention (F = 1.092, P = .035). Both interventions significantly increased albumin (F = 7.214, P = .003). Hemoglobin and creatinine significantly increased in the RT+WP group (F = 3.592, P = .035; F = 3.922, P = .033, respectively). In addition, a significant group × time interaction was not observed for body mass index, 5-time chair stand test time, 3-metre walk speed, grip strength, waist circumference, hip circumference, or waist-to-hip ratio (P > .05).Conclusions:Nutritional supplementation may be effective in improving sarcopenia, as well as many other physiological indicators during resistance training.

Free fatty acids are associated with muscle dysfunction in Chinese adults with type 2 diabetes.

Muscle dysfunction is considered a sign of poor prognosis in patients with type 2 diabetes (T2D). Thus, early detection of muscle disorders is particularly important in the T2D population. Free fatty acids (FFAs) are clinical indicators of metabolic diseases and muscle function; hence, we aimed to investigate the association between FFAs and muscle function. A total of 160 adult subjects with T2D were characterized and analyzed in this study. Muscle mass and function were measured by walking speed, grip strength and height-adjusted appendicular skeletal muscle mass (ASMM). Partial correlation was applied to explore the correlations between FFAs and muscle indicators. Receiver operating characteristic (ROC) curves were utilized to determine the diagnostic value of FFAs in muscle mass and function. The FFAs levels were negatively correlated with ASMM (r = -0.347, P = 1.0E-05), grip strength (r = -0.313, P = 7.1E-05) and walking speed (r = -0.167, P = 0.039). Notably, the relationships between FFAs levels and ASMM and walking speed remained significant even after adjusting for age, sex, body mass index (BMI), diabetes duration, and hemoglobin A1C (HbA1c). The combination of conventional indicators, including age, BMI, and HbA1c levels, provided a discrimination of low grip strength with an AUC of 0.648, and low walking speed with an AUC of 0.714. Importantly, when FFAs levels were added to the model, the value of the ROC curve was further improved, with an AUC of 0.785 for low grip strength and 0.755 for low walking speed. The current study demonstrated a negative correlation between FFAs and muscle indicators in adult patients with T2D after adjusting for HbA1c levels. FFAs may play an important role in the pathological processes of muscle dysfunction in adults with T2D.

Association Between Length of Stay in the Intensive Care Unit and Sarcopenia Among Hemiplegic Stroke Patients.

ObjectiveTo discuss the association between the length of stay at the intensive care unit (ICU) and sarcopenia among hemiplegic stroke patients.MethodsThis study evaluated 66 hemiplegic stroke patients with history of ICU admission using handgrip strength and bioelectrical impedance analysis to obtain height-adjusted appendicular skeletal muscle mass. The diagnosis of sarcopenia was made according to the muscle mass based on the Asian Working Group for Sarcopenia. The patients were divided into sarcopenic and non-sarcopenic groups. The two groups were statistically analyzed, and the significant factors with differences were studied. A multivariate logistic regression analysis was performed to examine the association between length of stay in the ICU and sarcopenia, after adjusting for potential confounders.ResultsAmong 66 hemiplegic patients with an ICU admission history, 12 patients were diagnosed with sarcopenia. Sarcopenia patients showed lower scores on the Korean version of the Modified Barthel Index and the Korean version of the Mini-Mental State Examination. Additionally, patients with sarcopenia had a longer length of stay in the ICU, and univariate and multivariate analyses confirmed that the ICU length of stay was significantly related to sarcopenia (adjusted odds ratio=1.187; 95% confidence interval, 1.019–1.382; p=0.028).ConclusionThe length of stay in the ICU was significantly associated with sarcopenia in hemiplegic stroke patients.

Obesity and muscle may have synergic effect more than independent effects on brain volume in community-based elderly.

To evaluate the individual and combined effects of obesity and muscle mass on brain volume in a community-dwelling healthy older population. One thousand two hundred nine participants (M:F = 574:635, mean age 63.6 ± 6.9years) were included. The cross-sectional area of visceral fat (VF), the height-adjusted appendicular skeletal muscle mass (ASM/height2), and the ratio of thigh muscle to visceral fat (TM/VF) represented obesity, muscle mass, and their integrated value, respectively. Linear regression analysis was performed to establish associations between 215 brain compartment volumes and VF, ASM/height2, and TM/VF after adjusting for covariates. On regression analysis, TM/VF had a positive correlation to the volumes of temporal lobe and cerebellum. TM/VF was associated with volumes of 10 subcompartments. TM/VF was positively correlated with the volumes of left entorhinal cortex, right temporal pole and inferior temporal gyrus related to cognition (p< 0.05, respectively), and the volumes of cerebellum and right pallidum related to movement (p< 0.05, respectively). However, VF had a negative correlation to temporal lobe volume and ASM/height2 had no significant correlation to any of the brain lobes. VF and ASM/height2 were correlated with volumes of 5 subcompartments and one subcompartment, respectively, CONCLUSIONS: TM/VF reflects the integrated effect of obesity and muscle mass and is associated with the volume of more brain regions compared to indices of obesity or muscle mass alone. The positive effect of muscle mass and the negative effect of obesity change the volumes of brain regions related to cognition and movement which were not significantly affected by obesity or muscle mass alone. • If obesity and muscle mass were considered together, we could find more significant brain volume changes which were not found in obesity or muscle alone. • The ratio of thigh muscle to visceral fat was positively correlated with the volumes of entorhinal cortex, temporal pole, and inferior temporal gyrus related to cognition. • The ratio of thigh muscle to visceral fat was positively correlated with the volumes of cerebellum and pallidum related to movement.

Sarcopenia, sarcopenic overweight/obesity and risk of cardiovascular disease and cardiac arrhythmia: A cross-sectional study.

Sarcopenia is an age-dependent skeletal muscle disorder that is common in patients with heart failure. The current study aimed to investigate the associations of sarcopenia with carotid atherosclerosis, cardiovascular disease and cardiac arrhythmia in a middle-aged and elderly population without clinical heart failure. A total of 2432 participants (992 men and 1440 women) from Shanghai Changfeng Study were included for analysis. The degree of sarcopenia was measured using height-adjusted appendicular skeletal muscle mass (ASM/height2). Carotid plaques were detected by carotid artery ultrasonography, and myocardial ischemia, infarction and cardiac arrhythmia were diagnosed based on electrocardiogram, past history and clinical manifestations. Sarcopenia was associated with higher prevalence of carotid atherosclerosis (26.4% vs 20.4%, P=0.027), myocardial infarction (4.0% vs 1.1%, P=0.001), and premature ventricular contraction (4.0% vs 2.0%, P=0.034) in the participants with normal body weight, and higher prevalence of carotid atherosclerosis (45.0% vs 31.2%, P=0.016), myocardial infarction (10.0% vs 4.3%, P=0.020) and atrial fibrillation (7.5% vs 1.3%, P<0.001) in those with overweight/obese status. After adjustment for age, gender, cigarette smoking, alcohol drinking, menopausal status in women and other metabolic and inflammatory confounding factors, sarcopenia was independently associated with the risk of myocardial infarction in the whole population, and the risk of atrial fibrillation in the overweight/obese participants (all P<0.05). Compared with nonsarcopenic lean participants, the risk of myocardial infarction was gradually increased in sarcopenic lean (OR 3.08 [1.28-7.45], P=0.012) and sarcopenic overweight/obese participants (OR 4.07 [1.31-12.62], P=0.015). For the atrial fibrillation, the participants with either sarcopenia or overweight/obesity alone showed no higher risk. However, concomitant sarcopenia and overweight/obesity was associated with approximately 5-fold risk of atrial fibrillation (OR 5.68 [1.34-24.12], P=0.019) after multiple adjustment. Sarcopenia is associated with myocardial infarction and atrial fibrillation in middle-aged and elderly adults without clinical heart failure.

Diagnosis of Presarcopenia Using Body Height and Arm Span for Postmenopausal Osteoporosis.

PurposeSarcopenia and osteoporosis are both serious health problems in postmenopausal women. The Asia Working Group for Sarcopenia recommends using the skeletal muscle index (SMI), which is height-adjusted appendicular skeletal muscle mass (ASMM). However, loss of height has been shown to be a common clinical finding in patients with osteoporosis. This study examined the prevalence of presarcopenia using height and arm span, which is a predictor of height, and investigated the diagnostic accuracy for presarcopenia.MethodsA total of 55 post-menopausal osteoporotic patients aged 62–95 years underwent bioelectrical impedance analysis (BIA) for ASMM measurement and dual-energy X-ray absorptiometry (DXA) scan for bone mineral density (BMD). Anthropometric measurements, including height, weight, and arm span were taken, and body mass index (BMI), SMI, and arm span-adjusted SMI (Arm span SMI) were calculated. Presarcopenia was defined as SMI or Arm span SMI <5.7 kg/m2 in this study.ResultsThe prevalence of presarcopenia was 27.3% and 38.2% evaluated by SMI and Arm span SMI, respectively. The prevalence of presarcopenia was higher when evaluated by Arm span SMI than by SMI. In the presarcopenia group diagnosed only by Arm span SMI (n=11), the arm span-height difference was significantly higher (p<0.001) and the percentage of young adult mean (YAM) femoral neck-BMD was significantly lower (p=0.013) compared to the normal group diagnosed by both SMI and Arm span-SMI (n=29).ConclusionThese results indicated that Arm span SMI might be useful for the diagnosis of sarcopenia in patients with severe osteoporosis and kyphosis.

Grip strength mediates the relationship between muscle mass and frailty.

BackgroundAlthough sarcopenia and frailty are important diseases in geriatrics, few studies have investigated the association between the two diseases. Thus, this study aimed to examine the relationship between two components of sarcopenia (muscle mass and muscle function) and frailty.MethodsIn total, 997 Korean older adults (456 men and 541 women) were included in this cross‐sectional observational study. We used a polynomial linear regression analysis to obtain standardized sex, age, and height‐adjusted appendicular skeletal muscle mass (zASM), as well as to standardized sex, age, and height‐adjusted grip strength (zGS). We then performed a causal mediation analysis to confirm the relationship between zASM and frailty.ResultsIn both men and women, zGS mediated the relationship between zASM and frailty (average causal mediation effect in men: −0.096 {−0.159 to −0.050}; in women: −0.053 {−0.098 to −0.010}). For every one‐point increase in zGS score, the relative risk of a one‐point increase in frailty was reduced by 21% in men (e−0.238 = 0.788) and by 11% in women (e−0.113 = 0.893).ConclusionsIn this study on Korean older adults, muscle mass did not have a direct effect on frailty but had an indirect effect through altered muscle function.

Relationship between visual acuity and muscle mass in the Korean older population: a cross-sectional study using Korean National Health and Nutrition Examination Survey

ObjectivesWe aimed to assess the effects of visual acuity on muscle mass, which is an important indicator of health in older populations.DesignPooled-sample cross-sectional study.SettingNationally representative population survey data.ParticipantsThe present study...

Serum Myostatin and IGF-1 as Gender-Specific Biomarkers of Frailty and Low Muscle Mass in Community-Dwelling Older Adults.

(i) To investigate serum myostatin (absolute and normalized for total body lean mass (TBLM)) and IGF-1 as biomarkers of frailty and low relative appendicular skeletal muscle mass (RASM) in older adults, and; (ii) to examine gender differences in the association of serum myostatin and IGF-1 levels with frailty and low RASM. Cross-sectional study. The "Longitudinal Assessment of Biomarkers for characterization of early Sarcopenia and predicting frailty and functional decline in community-dwelling Asian older adults Study" (GERI-LABS) study in Singapore. 200 subjects aged 50 years and older residing in the community. Frailty was assessed using the modified Fried criteria. Low RASM was defined using cutoffs for height-adjusted appendicular skeletal muscle mass measured by dual-energy X-ray absorptiometry as recommended by the Asian Working Group for Sarcopenia. Comorbidities, cognitive and functional performance, physical activity and nutritional status were assessed. Blood samples collected included serum myostatin, insulin-like growth factor 1 (IGF-1) and markers of inflammation (total white cell count, CRP, IL-6 and TNFaR1). Subjects were classified into 4 groups: Frail/Prefrail with low RASM (Frail/Low RASM), Frail/Prefrail with normal RASM (Frail/Normal RASM), Robust with low RASM (Robust/Low RASM) and Robust with normal RASM (Robust/Normal RASM). 63 (32%) subjects were classified as Frail/Low RASM, 53 (27%) Frail/Normal RASM, 28 (14%) Robust/Low RASM and 56 (28%) Robust/Normal RASM respectively. Frail/Low RASM subjects were older and had lower BMI compared to Frail/Normal RASM and robust subjects. Mean (SE) normalized myostatin levels were higher in Frail/Low RASM compared to Frail/Normal RASM subjects (1.0 (0.04) versus 0.84 (0.05) ng/ml/kg, P=0.01). Median (IQR) IGF-1 level was lower amongst Frail/Low RASM subjects compared to Frail/Normal RASM subjects (102.3, (77.7, 102.5) vs 119.7 (82.7, 146.0) ng/ml, P=0.046). No differences in myostatin or IGF-1 were observed among robust individuals with or without low muscle mass. In adjusted multinomial logistic regression models with Robust/Normal RASM as the reference group, myostatin (P=0.05) and IGF-1 (P=0.043) were associated with Frail/Low RASM status in the whole cohort. When stratified by gender, myostatin was significantly associated with Frail/Low RASM status in men only (P=0.03). In women, serum IGF-1 was associated with Frail/Low RASM status (P=0.046), but not myostatin (P=0.53). Serum myostatin, normalized for TBLM in men and IGF-1 in women are potential biomarkers for frail individuals with low RASM, and may identify a target group for intervention.

The Differential Effect of Excess Aldosterone on Skeletal Muscle Mass by Sex.

The effects of excess aldosterone on skeletal muscle in individuals with primary aldosteronism (PA) are unknown. To examine the effects of aldosterone on skeletal muscle mass in patients with PA, by sex, 309 consecutive patients were enrolled. Skeletal muscle and fat mass of 62 patients with PA were compared with those of 247 controls with non-functioning adrenal incidentaloma (NFAI). Body composition parameters were measured using bioelectrical impedance analysis, and plasma aldosterone concentration (PAC) was measured using radioimmunoassay. The PAC in all women, but not in men, showed an inverse association with both appendicular skeletal muscle mass (ASM) (β = −0.197, P = 0.016) and height-adjusted ASM (HA-ASM) (β = −0.207, P = 0.009). HA-ASM in women (but not in men) with PA was 5.0% lower than that in women with NFAI (P = 0.036). Furthermore, women with PA had a lower HA-ASM than 1:1 age- and sex-matched controls with NFAI by 5.7% (P = 0.049) and tended to have a lower HA-ASM than 1:3 age-, sex-, and menopausal status-matched controls without adrenal incidentaloma (AI) by 7.3% (P = 0.053). The odds ratio (OR), per quartile increase in PAC, of low HA-ASM in women was 1.18 [95% confidence interval (CI), 1.01–1.39; P = 0.035]. The odds of HA-ASM in subjects with PA were 10.63-fold (95% CI: 0.83–135.50) higher, with marginal significance (P = 0.069) than in those with NFAI. Skeletal muscle mass in women with PA was lower than that in women with NFAI; suggesting that excess aldosterone has adverse effects on skeletal muscle metabolism.

Heritability of muscle mass in Korean parent–offspring pairs in the Fifth Korean National Health and Nutrition Examination Survey (KNHANES V)

ObjectivesDecreased muscle mass is known to be associated with several serious medical conditions. We analyzed the Fifth Korean National Health and Nutrition Examination Survey (KNHANES V, 2010–2011) to estimate the heritability of muscle mass in Korean parent-offspring pairs. Study DesignCross-sectional. Main outcome measuresA total of 1233 parents (average age 57.67 ± 8.50 years) and 917 offspring (average age 29.10 ± 7.57 years) from 743 families were included in the analysis. Muscle mass was estimated based on three different indices: appendicular skeletal muscle mass (ASM) measured with a dual-energy X-ray absorptiometry (DXA), weight-adjusted ASM (SMI), and height-adjusted ASM (RASM). The heritability was estimated by employing the maximum-likelihood variance components implemented in Sequential Oligogenic Linkage Analysis Routines (SOLAR). The best-fitting model was determined out of four polygenic models. Pearson’s partial correlation coefficient was also calculated using the muscle mass indices to further study the association between father or mother and son or daughter pairs. ResultsThe heritability estimates of the muscle mass indices ranged from 55% to 80% (all p < 0.01). The correlation coefficient of father and offspring ranged from 0.11 to 0.40, while that of mother and offspring ranged from 0.23 to 0.43 (all p < 0.01). ConclusionsThe heritability estimates of muscle mass in Koreans are large and significant, suggesting that parental muscle mass is an important predictor of the offspring’s muscle mass. The result implies that there may be a genetic factor partly determining muscle mass.

Alteration in skeletal muscle mass in women with subclinical hypercortisolism.

Despite the well-known deleterious effects of cortisol on skeletal muscle, whether subtle cortisol excess in subclinical hypercortisolism (SH) affects skeletal muscle mass is unknown. Our objective was to understand the effects of the cortisol level on skeletal muscle mass in patients with SH. We compared skeletal muscle mass and fat mass (FM) between 21 patients with SH (12 women and 9 men) and 224 controls (67 women and 157 men) with nonfunctioning adrenal incidentaloma (NFAI). Medical records were reviewed, and we measured body composition parameters using bioelectrical impedance analysis and serum cortisol levels after the overnight 1-mg dexamethasone suppression test (DST). After adjusting for confounding factors, 1-mg DST levels were inversely correlated with appendicular skeletal muscle mass (ASM) (γ = -0.245, P = 0.040), lower limb ASM (γ = -0.244, P = 0.040), and appendicular skeletal muscle index (ASMI; height-adjusted ASM) (γ = -0.229, P = 0.048) in all women, but not men. ASM and ASMI were significantly lower by 6.2% (P = 0.033) and 5.9% (P = 0.046), respectively, in women with SH compared with those with NFAI, but not men. Conversely, FM and percent fat mass were similar between the two groups. Compared with women with NFAI, among those with SH, lower limb, but not upper limb, ASM was lower by 6.8% (P = 0.020). This study showed that women with SH had lower skeletal muscle mass, especially of the lower limb, and suggested that subtle cortisol excess also has adverse effects on skeletal muscle metabolism.

Effect of sleep duration on muscle mass in Korean non-elderly adults

Objective: This study investigated the association of sleep duration and muscle mass in non-elderly adults. Methods: The present study analyzed young (19-39 years) and middle-aged (40-59 years) men and women who participated in the Korea National Health and Nutrition Examination Survey. Muscle mass was measured using dual energy X-ray absorptiometry scan. A self-reported questionnaire was used for assessing sleep duration, which was categorized into ≤ 6, 7, 8, and ≥ 9 h per day. Results: Participants with low muscle mass were more prevalent in the longer sleep group, among men and women. Furthermore, in subgroup analysis, in which participants were classified into a young and middle-aged group, height-adjusted appendicular skeletal muscle mass was inversely related to sleep duration, regardless of sex. After adjusting for covariates, the probability of low muscle mass was increased in longer sleepers, and sleep duration and low muscle mass showed a positive dose-dependent correlation in men and women. Conclusion: In young and middle-aged adults, longer sleep duration may be related to decreased muscle mass, in both sexes.