Author(s): Panita Limpawattana, Prasert Assantachai, Orapitchaya Krairit, Thepkhachi Kengkijkosol, Waratchamon Wittayakom, Jiraporn Pimporm, Ampornpan Theeranut
Low skeletal muscle mass and its predictors have been studied widely in older adults. There are few data; however, about their association in young Thai adults. The objectives of this study were to identify risk factors of low relative appendicular skeletal muscle mass (RASM) in young adults by sex-specific groups and to determine optimal cut-off points for low RASM for those adults. This was a cross-sectional study. Healthy urban subjects in Khon Kaen, Thailand who were aged 20-39 year were recruited. Baseline characteristics were collected. Body composition estimation was determined using bioelectrical impedance analysis. One-hundred women and 100 men were recruited for this study. The median RASM was 6.13 kg/m2 in women and 8.01 kg/m2 in men. The cut-off points for low RASM were 5.68 kg/m2 in women and 7.22 kg/m2 in men. For women, increased fat mass (FM), and total body water (TBW) were associated with increased RASM with odds ratios (OR) of 1.04 (95% confidence intervals (CI) 1.02, 1.05) and 1.06 (95%CI 1.02, 1.1). Non-sedentary lifestyles were also related to increased RASM (OR 1.23, 95% CI 1.02, 1.57) whereas current smoking were associated with low RASM (OR 0.45, 95% CI0.21, 0.96). For men, RASM showed a positive association only with FM (OR 1.11, 95% CI 1.07, 1.15) and TBW (OR 1.07, 95% CI 1.04, 1.09). In conclusion, FM and TBW were positively associated with RASM in young Thai adults independent of gender. Current smoking and a sedentary lifestyle were predictors of low RASM in women. The results from this study support the standard cutoff values of low RASM among Asians.