Cost-effectiveness of implantable cardioverter defibrillators in patients ≥65 years of age

Background: More than 80% of sudden cardiac deaths (SCDs) occur in patients ≥65 years old; the cost-effectiveness of implantable cardioverter defibrillator (ICD) therapy in older patients remains unclear. We sought to examine the cost-effectiveness of ICD therapy in at-risk patients ≥65 years old. Methods: We developed a Markov model to evaluate lifetime costs and benefits of ICD therapy compared with optimal medical therapy in patients ≥65 years of age with left ventricular dysfunction. Data were derived from the literature and existing clinical trials of primary prevention of SCD. Outcome measures included life years, quality-adjusted life years, costs, and incremental cost-effectiveness. Results: Benefits and costs of ICD therapy in older individuals varied widely by clinical-trial population. In the 5 trials considered, for patients ≥65 years of age, ICDs demonstrated a life expectancy benefit compared with control therapy (incremental cost-effectiveness ratios ranging from $37,031-$138,458 per quality-adjusted life year). For 75-year-old patients, the findings were qualitatively similar, although cost-effectiveness was reduced in all trial populations. In sensitivity analyses, cost-effectiveness of ICD therapy in older individuals depended upon the trial population, quality of life, device cost, and frequency of generator replacement. Sensitivity analyses on other variables did not change the results substantially. Conclusions: The cost-effectiveness of ICD therapy for primary prevention in older patients varies widely among trials. Given an aging US population and the high risk of SCD in these individuals, further studies of ICD therapy and their cost-effectiveness-specifically in older patients-are needed.