摘要：Objectives. We investigated the association between major depressive disorder and type 2 diabetes, whether that association is explained by health behaviors, and whether it is influenced by educational attainment. Methods. We used discrete-time Cox proportional hazards models to determine the risk of type 2 diabetes associated with depression in a 23-year population-based cohort study. Results. Major depressive disorder was associated with higher risk of type 2 diabetes (hazard ratio [HR]=1.62) after we controlled for age, gender, race, education, smoking status, alcohol use, social network size, and antidepressant use. This association was more pronounced after we controlled for body mass index, family history, and health behaviors (HR=2.04; 95% confidence interval=1.09, 3.81). In stratified analyses, the risk associated with major depressive disorder was elevated among those with 12 or fewer years of education compared with those with at least some education beyond high school. Conclusions. The risk of type 2 diabetes associated with major depressive disorder persists over the life course and is independent of the effects of health behaviors, body mass index, and family history. Education is an important moderator of this association. Numerous retrospective observational studies have reported higher prevalence of depression among diabetic populations than among controls. 1 , 2 In the first prospective analysis, Eaton et al. found approximately 2 times higher risk of type 2 diabetes among those with major depressive disorder (MDD) 13 years previously than among those without depression, 3 a finding that has been replicated with remarkable consistency. 4 It is unclear whether the elevated risk of type 2 diabetes associated with depression is mediated by poor health behaviors (e.g., smoking, physical inactivity), physiological changes, or both. Depression is associated with lower socioeconomic status, 5 but it is unknown whether indicators such as educational attainment moderate the associated risk of type 2 diabetes. One previous study suggested that the risk of type 2 diabetes among persons with depression was substantially greater among those with less than a high school education than among more-educated groups. 6 We prospectively examined the relationship between depression and type 2 diabetes, seeking to answer 2 questions: Do established risk factors for diabetes, such as family history, obesity, smoking, alcohol intake, dietary habits, and physical inactivity, explain the association between depression and risk of diabetes? Does educational attainment modify this relationship?
