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.