Are the obese at greater risk for depression?

Two waves of data from a community-based study (Alameda County Study, 1994- 1995) were used to investigate the association between obesity and depressi on. Depression was measured with 12 items covering Diagnostic and Statistic al Manual of Mental Disorders: DSM-IV diagnostic criteria for major depress ive episode. Following US Public Health Service criteria, obese subjects we re defined as those with body mass index scores at the 85th percentile or h igher. Covariates were age, sex, education, marital status, social isolatio n and social support, chronic medical conditions, functional impairment, li fe events, and financial strain. Results were mixed. In cross-sectional ana lyses, greater odds for depression in 1994 were observed for the obese, wit h and without adjustment for covariates. When obesity and depression were e xamined prospectively, controlling for other variables, obesity in 1994 pre dicted depression in 1995 (odds ratio (OR) = 1.73, 95% confidence interval (CI): 1.04, 2.87). When the data were analyzed with obesity defined as a bo dy mass index of greater than or equal to 30, cross-sectional results were the same. However, the prospective multivariate analyses were not significa nt (OR = 1.43, 95% CI: 0.85, 2.43). Although these data do not resolve the role of obesity as a risk factor for depression, overall the results sugges t an association between obesity and depression. The authors found no suppo rt for the "jolly fat" hypothesis (obesity reduces risk of depression). How ever, there has been sufficient disparity of results thus far to justify co ntinued research.