Abstract 158: Heart Failure and Outcomes after Acute Coronary Syndrome in a Representative Medicare Population

Abstract

Background: Heart failure (HF) is a common comorbid condition of elderly patients with acute coronary syndrome (ACS). The objective of this study is to compare the incidence of death and cardiovascular (CV) events among Medicare beneficiaries hospitalized for ACS) with and without comorbid HF. Methods: Patients hospitalized for ACS between 3/1/2002 - 12/31/2006 were identified from the Medicare Current Beneficiary Survey (date of first such admission denoted as the index date). Incident patients were selected defined as those with no ACS event in the 6 month pre-index period. Patients were stratified based on the presence (HF+) or absence (HF-) of medical claims for HF during the 6 months pre-index period. Comparisons of incidence of death and CV-related hospitalization were made between HF+ and HF-cohorts descriptively via Kaplan Meier curves and also with Cox proportional regressions adjusting for differences in patient characteristics. Sample population weights were applied accounting for multi-stage sampling design to obtain nationally representative estimates for the US Medicare population. Results: A final sample of 795 incident ACS patients were included (mean age 76 years; 49% male), of which 198 were HF+ (weighted prevalence=24.9% from the 2.5 million beneficiaries that these patients represent). The incidence of death after ACS admission among HF+ and HF- patients was 580 and 240 per 1,000 person years, respectively (p<0.01). If patients were discharged alive, HF+ patients had a significantly higher risk of subsequent CV events (812 vs. 355 cases; p<0.01) when 1,000 patients were followed for 6 months. After regression adjustment, there was a significant increased risk of mortality (HR=1.45; 95% CI: 1.09 - 1.93) and CV events (HR=1.72; 95% CI: 1.35 - 2.19) associated with comorbid HF. Conclusion: Our real-world findings suggest significantly poorer outcomes associated with HF among Medicare beneficiaries hospitalized for ACS. Personalized interventions targeting patients with both HF and ACS may improve the outcomes and quality of care.