The natural course of elevated levels of depressive symptoms in patients with vascular disease over eight years of follow-up. the SMART-Medea study

Background Patients with cardiovascular disease have an increased risk for depression, and depression predicts poor prognosis in these patients, but the long-term course of depression is not known. We studied the natural course of elevated levels of depressive symptoms in patients with cardiovascular disease over eight years follow-up. Methods Within the Second Manifestations of ARTerial disease - Memory, depression and aging (SMART-Medea) study, depressive symptoms were assessed with the Patient Health Questionnaire-9 (PHQ-9) in 690 patients (62±10 years) at baseline and bi-annually during 8 years follow-up. Natural course was described for symptom severity and course type (never, single episode, intermittent, and chronic) based on the cut-off point of ≥6 on the PHQ-9. Using multinomial regression analysis (reference: never depressed) we estimated age- and sex-adjusted odds ratios (OR) for the associations of demographic factors and vascular disease categories with course type. Results Of the 690 patients, 60% was never depressed, 10% had a single episode, 19% had an intermittent and 11% a chronic course of depression. Increased risk for chronic course was observed for women (OR=3.42; 95% CI=1.98-5.90), those with younger age (OR=3.20; 95% CI=1.73-5.94), and for patients with cerebrovascular disease when compared to patients with coronary artery disease (OR=2.50; 95% CI=1.31-4.78). Limitations No information was available on clinical diagnosed major depressive disorder and/or clinical events during follow-up. Conclusions In patients with cardiovascular disease, an intermittent or chronic course of elevated levels of depressive symptoms is very common. Patients with cardiovascular disease may require more careful clinical monitoring and management of depressive symptoms.