Cost of care for new versus recurrent acute coronary syndrome patients

INTRODUCTION: The economic burden of acute coronary syndrome (ACS) continues long after the acute event has resolved. This study compared ACS-related costs between new and recurrent ACS patients using retrospective claims data from a large US health plan. METHODS: Patients with ACS were identified using ICD-9 codes between the 1st January 2001 and the 30th June 2003. The first diagnosis was defined as the index event. Patient claims were examined 1 year before, and up to 1 year after, the index event. Hospitalisations, revascularisations and costs for new and recurrent cohorts were compared. Multivariate regression was used to examine cost predictors. RESULTS: In total, 15,508 patients were identified, 82% had new ACS. The new ACS cohort was more likely to have myocardial infarction and be hospitalised for the index event, leading to higher index event costs. However, the recurrent ACS cohort had more re-hospitalisations, longer lengths of inpatient stay and a higher probability of revascularisation during follow-up. The index event cost per patient and per patient-month was higher for new ACS patients. After adjusting for confounding factors, multivariate cost models revealed annualised follow-up medical costs were 9.9% higher (p=0.017) and annualised follow-up pharmacy costs were 8.3% higher (p< or =0.0001) for the new ACS cohort. CONCLUSION: Newly diagnosed ACS patients had significantly higher adjusted costs in the year following the index event, but recurrent ACS patients still experienced high medical costs. More emphasis by providers and patients on adherence to treatment guidelines may be one step to improving patient outcomes. *This paper was presented in part at the Academy of Managed Care Pharmacy Annual Meeting, 7th April 2006.