Ventricular tachyarrhythmias and mortality in patients with an implantable cardioverter defibrillator: Impact of depression in the MIDAS cohort

Objective: We examined whether depression is independently associated with implantable cardioverter defibrillator (ICD) therapy for ventricular tachyarrhythmias and mortality. Methods: A cohort of 430 consecutive patients with a first-time ICD (79% men; mean [standard deviation] age = 57.8 [12.1] years) completed the Hospital Anxiety and Depression Scale 1 day before implantation. During follow-up, the ICD was interrogated at 3-month intervals. Cox proportional hazard regression analyses were used to examine the impact of depression on time to first appropriate ICD therapy and all-cause mortality during a median follow-up period of 3.8 years. Results: Of all patients, 108 (25.1%) were depressed. Depression was not associated with time to first appropriate ICD therapy (unadjusted hazard ratio [HR] = 1.07, 95% confidence interval [CI] = 0.73Y1.56). However, depression was associated with an increased risk for all-cause mortality (unadjusted HR = 2.18, 95% CI = 1.36Y3.49). Depression remained independently associated with all-cause mortality (HR = 1.94, 95% CI =1.06Y3.54, p = .031), after adjusting for demographic and clinical characteristics. Patients who remained depressed during the first 3 months after implantation were at greatest risk for dying (HR = 2.88, 95% CI = 1.29Y6.45, p = .010). Conclusions: The current study showed that depression at the time of implant is not associated with time to first appropriate ICD therapy but almost doubled the risk for all-cause mortality in patients with an ICD. Patients with persistent depression during the first 3 months after implantation face the greatest risk of dying. Current evidence indicates that multifactorial interventions are likely to be the most successful in terms of reducing distress. Whether this translates into enhanced survival has yet to be determined. Key words: implantable cardioverter defibrillator, depression, ventricular tachyarrhythmias, mortality