Persistence of Depressive Symptoms and Risk of Incident Cardiovascular Disease With and Without Diabetes: Results from the REGARDS Study

Background Baseline depressive symptoms are associated with subsequent adverse cardiovascular (CV) events in subjects with and without diabetes but the impact of persistent symptoms vs. improvement remains controversial. Objective Examine long-term changes in depressive symptoms in individuals with and without diabetes and the associated risk for adverse CV events. Design REGARDS is a prospective cohort study of CV risk factors in 30,000 participants aged 45 years and older. Participants N = 16,368 (16.5% with diabetes mellitus) who remained in the cohort an average of 11.1 years later and who had complete data. Main Measures Depressive symptoms were measured using the 4-item Centers for Epidemiologic Study of Depression (CES-D) questionnaire at baseline and again at a mean follow-up of 5.07 (SD = 1.66) years. Adjudicated incident stroke, coronary heart disease (CHD), CV mortality, and a composite outcome were assessed in a subsequent follow-up period of 6.1 (SD = 2.6) years. Methods The association of changes in depressive symptoms (CES-D scores) across 5 years with incident CV events was assessed using Cox proportional hazards modeling. Key Results Compared to participants with no depressive symptoms at either time point, participants without diabetes but with persistently elevated depressive symptoms at both baseline and follow-up demonstrated a significantly increased risk of incident stroke (HR (95% CI) = 1.84 (1.03, 3.30)), a pattern which was substantially more prevalent in blacks (HR (95% CI) = 2.64 (1.48, 4.72)) compared to whites (HR (95% CI) = 1.06 (0.50, 2.25)) and in those not taking anti-depressants (HR (95% CI) = 2.01 (1.21, 3.35)) in fully adjusted models. Conclusions The persistence of depressive symptoms across 5 years of follow-up in participants without diabetes identifies individuals at increased risk for incident stroke. This was particularly evident in black participants and among those not taking anti-depressants.