Effect of Depression on Mortality in Implantable Cardioverter Defibrillator Recipients—Findings from the Prospective LICAD Study

INTRODUCTION: Depression predicts mortality in patients with coronary artery disease and heart failure. However, its effect on patient outcome in the presence of an implantable cardioverter defibrillator (ICD) has not been investigated. METHODS: A total of 236 ICD patients (76 females, 58.6 ± 14.0 years) were screened for depressive symptoms using the Hospital Anxiety and Depression Scale (HADS). The outcome measure was all-cause mortality and the prognostic effect of depression was evaluated with Cox proportional hazards regression analysis. RESULTS: Fifty (21%) patients reported depressive symptoms (HADS score ≥ 8). Renal failure (odds ratio [OR]= 4.0, 95% confidence intervals [CI]= 1.47-10.87, P = 0.007), prior angina (OR = 2.1, 95% CI = 1.07-4.12, P = 0.03), but not the experience of ICD shocks were associated with baseline depressive symptoms. In a mean follow-up period of 6.1 ± 2.5 years, 74 patients (31%) died. Mortality significantly increased from 45.1 deaths per 1,000 person-years among patients without depression to 80.3 deaths per 1,000 person-years in patients with depressive symptoms (P = 0.039). In the univariate model, depression (HADS score ≥8) was a significant predictor of mortality (OR = 1.81, 95% CI = 1.1-3.0, P = 0.02). However, in the multivariate model, depression lost its prognostic significance. CONCLUSIONS: In our prospective patient cohort, one-fifth of ICD recipients reported depressive symptoms. Depression increased the absolute mortality risk but was not an independent predictor of mortality.