Depression and all-cause mortality in patients with congestive heart failure and an implanted cardiac device

OBJECTIVE: The purpose of this study was to assess the association between depression and all-cause mortality in patients with congestive heart failure (CHF) and an implanted cardiac device. METHODS: The study enrolled 260 patients (mean age 56.8±10.0 years; 83.1% male) with CHF and an implanted cardiac device (156 patients with a resynchronization therapy cardiac device, 104 patients with an implantable cardioverter defibrillator). The mean duration of follow-up was 48.6±32.2 months. The Beck Depression Inventory was used to measure depressive symptoms. Depression was considered absent for a score between 0 and 9, mild to moderate for a score between 10 and 18, and severe if the score was 19 or greater. The Cox proportional hazards regression model was used to estimate hazard ratios (HR) with a 95% confidence interval (CI) for the impact of depression on all-cause mortality. The HR was calculated after adjustment for the following confounders: age, gender, smoking status, hypertension, diabetes mellitus, body mass index, hypercholesterolemia, left ventricular ejection fraction, number of hemodynamically significant lesions of the coronary arteries, and the type of implanted cardiac device. RESULTS: During the follow-up period, 37 patients died (14.2%). The adjusted HR of depression for all-cause mortality was 1.05, with a 95% CI of 1.01-1.09. Patients without depression were accepted as a reference group with HR=1.0 for analysis of the categorical indicator. The HR was 1.32, with a 95% CI of 0.57-3.03, in patients with mild depressive symptoms, and the HR was 3.18 with a 95% CI of 1.31-7.73 in patients with severe depressive symptoms. CONCLUSION: Increased depressive symptoms were independently associated with all-cause mortality in patients with CHF and an implanted cardiac device.