Skeletal muscle loss is associated with diabetes in middle-aged and older Chinese men without non-alcoholic fatty liver disease

BACKGROUND: Skeletal muscle, a key insulin target organ, has been reported to be associated with diabetes mellitus (DM). Compared to non-diabetic patients, diabetic patients have decreased muscle mass and a higher prevalence of sarcopenia, and patients with sarcopenia may be at increased risk of developing diabetes. In individuals with nonalcoholic fatty liver disease (NAFLD), sarcopenia is associated with the severity of fibrosis and steatosis. Previous studies have demonstrated that NAFLD is strongly associated with DM and sarcopenia. AIM: To determine the relationship between skeletal muscle mass and DM in Chinese middle-aged and elderly men, and whether the association is affected by NAFLD. METHODS: Skeletal muscle mass was calculated as appendicular skeletal muscle mass (ASM) in kg/body weight × 100%. Liver fat content (LFC) was measured using a quantitative ultrasound method. RESULTS: As the ASM decreased, fasting blood glucose (FBG), 2-h postprandial blood glucose (2hBG), and LFC increased in both genders, as did the prevalence of DM and NAFLD. Spearman analysis showed that the ASM was negatively correlated with the FBG, 2hBG, and LFC. Stepwise logistic regression analysis showed that after adjustments, the ASM quartile was negatively associated with the presence of DM in males, but not in females. Subgroup analysis showed that the ASM quartiles remained negatively correlated with the presence of DM in the non-NAFLD population (including males and females), but no correlation was found between ASM quartiles and the presence of DM in the NAFLD population. When stratified by LFC quartiles, ASM was negatively correlated with the presence of DM in the first and second LFC quartiles in males. CONCLUSION: Skeletal muscle mass loss was shown to be associated with the presence of DM in males, but not in females; NAFLD weakens this association. The results suggested that the stratified management of diabetes mellitus should be considered according to skeletal muscle mass and NAFLD.