Sex Differences in the Influence of Sleep on Body Mass Index and Risk of Metabolic Syndrome in Middle-Aged Adults

Poor sleep and obesity are intimately related to cardiovascular diseases. We aimed to examine whether the influence of sleep and body mass index (BMI) on the risk of metabolic syndrome (MetS) differed by sex in middle-aged people. It is a cross-sectional study of 458 Korean participants who completed self-administered surveys; the data were analyzed using the PROCESS macro for SPSS. We found that both sleep and BMI were significant predictors of MetS risk in women, particularly by the role of BMI connecting the impact of sleep to MetS risk. However, the association was not found in men, showing that BMI, but not sleep, was a significant predictor of MetS. This sex-related difference was due to different relationships between sleep and BMI, indicating that BMI was more dependent on sleep quality for women than for men. Therefore, a sex-specific approach to decrease the risk of MetS is warranted.