This study investigates whether obesity mediates the relationship between sleep duration and depressive symptoms, aiming to provide evidence for obesity's mediating effect and inform public health interventions. Data from 23,190 adults in the National Health and Nutrition Examination Survey (NHANES) 2007–2018 were analyzed. Generalized linear regression models assessed the associations between sleep duration, obesity indicators body mass index (BMI), waist circumference (WC), and body roundness index (BRI), and depressive symptoms. Mediation analysis explored the mediating role of obesity, with subgroup analysis across gender, age, and race. Sleep duration was significantly negatively associated with BMI, WC, and BRI (all P < 0.001), and these obesity indicators were positively associated with depressive symptoms (all P < 0.001). Mediation analysis showed that obesity partially mediated the relationship between sleep duration and depressive symptoms, with slightly stronger effects observed in individuals with diabetes. Obesity, assessed by BMI, WC, and BRI, showed a modest, partial mediating role in the association between sleep duration and depressive symptoms, with exploratory evidence of larger indirect effects among individuals with diabetes.
Diao et al. (Wed,) studied this question.