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.