Obesity and onset of depression among U.S. middle-aged and older adults

This paper aims to examine the relationship between obesity and onset of depression among U.S. middle-aged and older adults. Methods: Data came from 1994 to 2010 waves of the Health and Retirement Study. Study sample consisted of 6514 community-dwelling adults born between 1931 and 1941 who were free of clinically relevant depressive symptoms in 1994. Body mass index (BMI) was calculated from self-reported height/weight. Body weight status was classified into normal weight (18.5kg/m²≤BMI<25kg/m²), overweight (25kg/m²≤BMI<30kg/m²), and obesity (BMI≥30kg/m²). A score of ≥3 on the 8-item Center for Epidemiologic Studies Depression Scale was used to define clinically relevant depressive symptoms. Kaplan-Meier estimator and time-dependent Cox proportional hazards model were performed to examine the association between body weight status and onset of clinically relevant depressive symptoms. Results: Unhealthy body weight was associated future onset of depression. Compared with their normal weight counterparts, overweight and obese participants were 13% (hazard ratio [HR] = 1.13, 95% confidence interval [CI] = 1.04-1.23) and 9% (HR = 1.09, 95% CI = 1.01-1.18) more likely to have onset of clinically relevant depressive symptoms during the 16. years of follow-up, respectively. The relationship between obesity and depression onset appeared stronger among females and non-Hispanic whites than their male and racial/ethnic minority counterparts. Conclusions: Health care providers should be aware of the potential risk for depression among obese older adults.