Background: It is well known that a low skeletal muscle mass (SMM) is associated with stroke. However, it is unknown whether increasing muscle mass can prevent stroke.
Methods: This community-based cross-sectional study was supported by the regional government. SMM measurements and brain computed tomography was performed in 722 stroke-free and dementia-free subjects (aged 50-75 years). Subjects were divided into quartiles (Q) by SMM, checked using the bioelectrical impedance analysis method (InBody 770, InBody, Seoul, Korea). Odds ratios (ORs) of brain white matter changes/silent infarction (WMC/SI) were calculated. The subjects were then divided into two groups by sex and evaluated.
Results: In the analysis of the four groups, the unadjusted ORs of Q2-Q4 were 0.616 (95% confidence interval [CI], 0.372-1.022; P = 0.061), 0.290 (CI, 0.159-0.530; P < 0.001), and 0.209 (CI, 0.108-0.403; P < 0.001) for the risk of WMC/SI. Adjusted ORs for age, hypertension, diabetes mellitus, education, hypercholesterolemia, and smoking were 0.994 (CI, 0.513-1.740; P = 0.085), 0.669 (CI, 0.329-1.362; P = 0.268), and 0.464 (CI, 0.219-0.984; P = 0.045). In the two-group (dichotomized) analysis, the unadjusted OR for the higher muscle mass groups (Q3 + Q4) was 0.313 (CI, 0.200-0.491; P < 0.001). The adjusted OR was 0.577 (CI, 0.340-0.979; P = 0.042). Considering sex, the adjusted OR were 0.351 (CI, 0.141-0.869; P = 0.024) in men and 0.771 (CI, 0.391-1.519; P = 0.452) in women.
Conclusions: Our findings suggest that increased SMM may protect against WMC/SI, especially in men.
Keywords: Bioelectrical impedance analysis (BIA); Body composition; Risk factor; Sarcopenia; Skeletal muscle mass; Stroke.