Depressive Symptom Clusters Differentially Predict Cardiovascular Hospitalization in People With Type 2 Diabetes.

BACKGROUND: Depression has been associated with the development of cardiovascular disease in people with type 2 diabetes. OBJECTIVE: We examined whether symptoms related to the 2 core features of depression--dysphoria and anhedonia--and anxiety were differentially associated with cardiovascular hospitalization and whether there were symptom-specific mechanisms (alcohol, smoking, physical activity, body mass index, glucose, cholesterol, and blood pressure) in play. METHOD: A total of 1465 people in Dutch primary care completed the Edinburgh Depression Scale in 2005 and were followed up until first cardiovascular hospitalization during follow-up (event) or December 31, 2010 (study end). Cox regression analyses examined (1) differences in time to hospitalization for a cardiovascular event between people with a low vs a high baseline dysphoria/anhedonia/anxiety score (adjusting for demographic and clinical confounders) and (2) mediating mechanisms. RESULTS: A total of 191 people were hospitalized for a cardiovascular event. In univariable analysis, dysphoria predicted a shorter time to cardiovascular hospitalization (hazard ratio = 1.49, 95% CI: 1.02-2.17). After adjustment for confounders, neither dysphoria (hazard ratio = 1.55, 95% CI: 0.91-2.64) nor anhedonia (hazard ratio = 0.83, 95% CI: 0.47-1.48) was significantly associated with time to cardiovascular hospitalization. Anxiety was associated with a longer time to cardiovascular hospitalization (adjusted hazard ratio = 0.49, 95% CI: 0.27-0.89). However, none of the selected factors qualified as a mediator for the (adjusted) association between anxiety and time to cardiovascular hospitalization. DISCUSSION: Dysphoria was associated with a shorter time to cardiovascular hospitalization in unadjusted analyses only, whereas anxiety predicted later hospitalization after confounder adjustment. Anhedonia did not show a significant association. Mechanistic pathways remain unclear.