Clinical and economic outcomes among hospitalized patients with acute coronary syndrome: an analysis of a national representative Medicare population

OBJECTIVE: To evaluate the clinical and economic burden of acute coronary syndrome (ACS), a common cardiovascular illness, in the Medicare population. METHODS: Data from the Medicare Current Beneficiary Survey were analyzed. Patients with incident hospitalization for ACS without similar events during the 6 months prior were included. Outcomes evaluated included inpatient mortality, 30-day mortality and readmission, subsequent hospitalization events, and total direct health care costs. Sample population weights were applied, accounting for multistage sampling design to obtain nationally representative estimates for the US Medicare population. RESULTS: Between March 1, 2002 and December 31, 2006, we identified 795 incident ACS patients (mean age 76 years; 49% male) representing 2,542,211 Medicare beneficiaries. The inpatient mortality rate was 9.71% and the 30-day mortality ranged from 10.96% to 13.93%. The 30-day readmission rate for surviving patients was 18.56% for all causes and 17.90% for cardiovascular disease (CVD)-related diagnoses. The incidence of death since admission was 309 cases per 1000 person–years. Among patients discharged alive, the incidence was 197 for death, 847 for CVD-related admission, and 906 for all-cause admission. During the year when the ACS event occurred, mean annual total direct health care costs per person were US$50,458, with more than half attributable to inpatient hospitalization ($27,609). CONCLUSION: In this national representative Medicare population, we found a substantial clinical and economic burden for ACS. These findings suggest a continuing unmet medical need for more effective management of patients with ACS. The continuous burden underscores the importance of development of new interventions and/or strategies to improve long-term outcomes.