Decreased muscle mass is not an independent risk factor for metabolic syndrome in Korean population aged 70 or older

Abstract

Context: The association of low muscle mass with cardiometabolic risks is still controversial.

Objective: The aim of this study was to investigate the relationship between low muscle mass and metabolic syndrome (MetS) according to the various muscle mass indices and to evaluate the influence of muscle mass on MetS independent of fat mass.

Design: Cross-sectional study

Subjects: About 841 men and 1106 women aged 70 or older from Korea National Health and Nutrition Examination Survey 2008-2010 MEASUREMENTS: We used various muscle mass indices: appendicular skeletal muscle mass (ASM) divided by height squared (ASM/Ht(2) ), ASM divided by body weight (ASM/Wt) and ASM adjusted for height and fat mass (residual). Low muscle mass is defined as ASM/Ht(2) and ASM/Wt below 2 SD of the sex-specific mean for healthy young adults. The sex-specific lowest quintile of the distribution of the residual was regarded as low muscle mass.

Results: The prevalence of MetS was higher in the population with low muscle mass defined by ASM/Wt, but lower in those defined by ASM/Ht(2) . However, after stratification according to the central obesity, low muscle mass was barely related with MetS. Meanwhile, when both ASM and fat mass were included in a logistic regression model, the odds ratios of 1 SD change of ASM for MetS were 1·07 (0·85-1·34) for men and 1·24 (1·04-1·47) for women, respectively.

Conclusions: The relationship between low muscle mass and MetS was different according to the various muscle mass indices. After controlling the influence of fat mass, decreased muscle mass was not an independent risk factor for MetS.