Posttraumatic stress symptoms and predicted mortality in patients with implantable cardioverter-defibrillators: results from the prospective living with an implanted cardioverter-defibrillator study

Abstract

Context: Cardiac disease and treatment with an implantable cardioverter-defibrillator (ICD) may be psychologically traumatic. Posttraumatic stress disorder (PTSD) is generally overlooked in cardiac patients, and no study to date (to our knowledge) has evaluated the effect of PTSD symptoms on the prognosis in patients with ICDs.

Objective: To test whether PTSD symptoms at baseline predict long-term mortality risk in patients with ICDs.

Design: Prospective cohort study with a mean follow-up period of 5.1 years, accounting for 743 person-years observed.

Setting: Data were derived from the Living With an Implanted Cardioverter-Defibrillator-Study, which initially included 211 patients with ICDs routinely attending the German Heart Center Munich outpatient clinic.

Participants: The Impact of Event Scale-Revised was used in 147 patients (125 men and 22 women) who qualified for the "A" criterion of PTSD (survival of a life-threatening event). Thirty-eight patients scoring in the upper quartile of the scale constituted the PTSD index group.

Main outcome measures: Mortality risk per 1000 person-years as assessed by Cox proportional hazards regression analysis based on an appropriate model fit (area under the curve, >0.80).

Results: Index patients experienced more anxiety and depression, had more cardiac symptoms, but showed no differences in left ventricular ejection fraction status or extent of ICD discharges compared with non-index patients. Forty-five patients (30.6%) died during the follow-up period. The relative mortality risk (multivariate adjusted for age, sex, diabetes mellitus, left ventricular ejection fraction, beta-blocker prescription, prior resuscitation, ICD shocks received, depression, and anxiety) hazard ratio was 3.45 (95% confidence interval, 1.57-7.60; P = .002) for the PTSD group. Compared with 55 fatal events per 1000 person-years in patients without PTSD, the long-term absolute mortality risk accounted for 80 fatal events per 1000 person-years in patients with PTSD.

Conclusion: The adverse effect of PTSD symptoms on the long-term mortality risk in ICD-treated cardiac event survivors, independent of disease severity, supports the need for routinely applied interdisciplinary psychosocial aftercare.