Sarcopenic Obesity and Metabolic Syndrome in Adult Caucasian Subjects

Total energy intake according to the level of skeletal muscle mass in Korean adults aged 30 years and older: an analysis of the Korean National Health and Nutrition Examination Surveys (KNHANES) 2008-2011

BACKGROUND/OBJECTIVES

Since gain or loss of skeletal muscle mass is a gradual event and occurs due to a combination of lifestyle factors, assessment of dietary factors related to skeletal muscle is complicated. The aim of this study was to investigate the changes in total energy intake according to the level of skeletal muscle mass.

SUBJECTS/METHODS

A total of 8,165 subjects ≥ 30 years of age from the Korean National Health and Nutrition Examination Surveys (KNHANES) 2008-2011 were included in the analysis, and multivariate-adjusted regression analyses were performed to analyze the association of the quartiles of sarcopenia index (SI) with energy intake of the study population after adjusting for age and metabolic parameters.

RESULTS

The increase in SI quartile was in proportion to the gradual decrease in systemic lipids and the anthropometric measurement of fat accumulation (P < 0.001). Subjects in higher SI quartiles tended to consume more total energy and energy-producing nutrients than those in lower quartiles (P < 0.001). After age, body weight, alcohol consumption, and metabolic parameters were adjusted in the analysis, total energy intake gradually increased according to the increase in SI quartile, and the association between total energy intake and SI was more pronounced in men. However, the risk (odd ratio) of having a low SI was not affected by any single macronutrient intake.

CONCLUSIONS

In this study, total energy intake was positively associated with SI and relative skeletal mass in both men and women. However, no significant association or a weak association was observed between any single macronutrient intake and skeletal muscle mass. The data indicated that acquiring more energy intake within the normal range of energy consumption may help to maintain skeletal muscle mass.

Poor Physical Function as a Marker of Sarcopenia in Adults with Class II/III Obesity

BACKGROUND

Adults with class II/III obesity [body mass index (in kg/m2) ≥35] may present with a phenotype characterized by low lean mass and excess fat mass, a condition known as sarcopenic obesity (SO). Little is known about the prevalence and relevance of SO in these individuals, primarily due to a lack of relevant diagnostic criteria.

OBJECTIVE

Here, we explored the definition of SO based on physical function as an outcome of interest in adults with class II/III obesity and applied this definition to compare clinical characteristics between SO and non-SO patients.

METHODS

In this cross-sectional analysis, patients' demographic, anthropometric, and biochemical characteristics, as well as comorbidities and physical activity levels, were collected at an obesity specialty clinic prior to any treatment. Body composition was assessed by dual-energy X-ray absorptiometry. Physical function was assessed by self-reported difficulties with activities of daily living (ADLs) from an 11-item questionnaire. Five SO definitions were tested against reported difficulty with ADLs with the use of receiver operating characteristic (ROC) analysis.

RESULTS

A total of 120 subjects (86% women) aged 46 ± 11 y were included. Based on ROC analysis, SO was best defined by an appendicular skeletal mass (ASM)/weight x 100 (%) <19.35% for women and <24.33% for men, resulting in a prevalence of 25% (n = 30, women 22.3%, men 41.2%). SO was significantly associated with older age, higher waist circumference, higher triglycerides, greater use of antihypertensive medications, and lower physical activity.

CONCLUSIONS

In this sample of adults with class II/III obesity, difficulties with ADLs were best associated with measures of ASM in relation to total body weight. Patients identified with SO using this criterion presented with poorer clinical outcomes such as factors of elevated cardiometabolic risk.

Association of muscle mass and fat mass with insulin resistance and the prevalence of metabolic syndrome in Korean adults: a cross-sectional study

Relationship of muscle mass and fat mass with insulin resistance and metabolic syndrome remains uncertain, especially among Asian population. We performed a cross-sectional study with 14,807 adult participants aged between 18 and 65 in the fourth and fifth Korea National Health and Nutrition Examination Survey with Dual Energy X-ray Absorptiometry (DEXA) data to investigate whether muscle mass and fat mass are associated with insulin resistance and metabolic syndrome. DEXA records were used to categorize the participants into four categories (low muscle/low fat, low muscle/high fat, high muscle/ low fat, and high muscle/high fat). Least square means and incidence rate ratios (IRR) were used to assess the associations of muscle mass and fat mass with insulin resistance and metabolic syndrome. After adjustment for potential confounders, high muscle/low fat was associated with significantly lower insulin resistance (P < 0.001) compared to low muscle/low fat. Low muscle/high fat (IRR: 1.90; 95% confidence interval [CI]:1.44-2.50, P < 0.001) and high muscle/high fat (IRR: 2.30; 95% CI:1.76-3.00, P < 0.001) were significantly associated with the prevalence of metabolic syndrome. Our study suggests that protective association of muscle mass with metabolic syndrome is attenuated by high fat mass in Korean adults.

Sarcopenia in Liver Disease: Current Evidence and Issues to Be sResolved

Sarcopenia is a common clinical symptom in aging and patients with wasting diseases, characterized by a decreased skeletal muscle mass. As a consequence of lifestyle change, the nonalcoholic fatty liver disease (NAFLD) presents a rising trend. In the past three decades, increasing evidence has proved that sarcopenia is related to NAFLD. In this chapter, we will summarize the emerging evidence of the predictive role of sarcopenia in NAFLD and review the diagnosis value, feasible mechanism, and therapy strategies of sarcopenia in NAFLD. Sarcopenia is a potential risk factor for NAFLD, and targeting sarcopenia can benefit NAFLD to some extent.