Depressive Symptoms and Risk of Type 2 Diabetes in Women

OBJECTIVE—To explore the relationship between depressive symptoms and incidence of type 2 diabetes in women. RESEARCH DESIGN AND METHODS—We conducted an analysis of 72,178 female nurses aged 45–72 years who did not have diagnosed diabetes and who answered the Medical Outcomes Study 36-Item Short-Form Health Status Survey (SF-36) at baseline in 1992. We calculated relative risks (RR) of type 2 diabetes for women with presence of depressive symptoms (i.e., Five-Item Mental Health Index [MHI-5] score >52). RESULTS—During 4 years of follow-up (282,317 person-years), 973 incident cases of type 2 diabetes were documented. Age-adjusted RR of developing type 2 diabetes for women with presence of depressive symptoms was 1.55 (95% CI 1.27–1.90). Additional adjustment for BMI resulted in a RR of developing type 2 diabetes of 1.36 (1.11–1.67). The multivariate RR of developing type 2 diabetes was 1.22 (1.00–1.50). After excluding women diagnosed with diabetes between 1992 and 1994, 472 incident cases of type 2 diabetes were documented for the follow-up period from 1994 to 1996 (148,889 person-years). The multivariate RR of developing type 2 diabetes for women with depressive symptoms was 1.29 (0.96–1.72). CONCLUSIONS—Our data suggest that depressive symptoms are associated with a modest increase in the risk of type 2 diabetes.