Economic and Clinical Impact of Stroke and Warfarin Use for Patients with Non-valvular Atrial Fibrillation

Abstract

**Background:** Atrial fibrillation (AF) is a common clinical problem and potent risk factor for stroke. However, real-world effectiveness and outcomes for AF patients are not well described. **Objective:** To compare the economic and clinical impact of stroke and warfarin use on patients with nonvalvular atrial fibrillation (NVAF). **Methods:** This was a retrospective analysis of medical and pharmacy claims of NVAF patients from a large commercial health insurance database (01/01/2005-12/31/2007). Patients were grouped according to stroke or warfarin prescription status. For all groups, demographic, clinical, and pharmaceutical characteristics were analyzed descriptively. Risk-adjusted overall and cardiovascular-related hospital readmission rates in 30 days, length of stay (LOS), clinical outcomes, and health care costs were assessed using propensity score matching. Costs were adjusted to 2007 U.S. dollars using the medical component of the U.S. Consumer Price Index. **Results:** Out of 18,575 NVAF patients, 3.1% (n=575) experienced a stroke event. Stroke patients were older on average (78.94 vs. 77.28 years, p-value0.0500). However, a significantly greater proportion of patients with major and minor bleeding were prescribed a combination of warfarin and antiplatelets than those without these events. **Conclusions:** A stroke after an NVAF diagnosis has a major clinical impact, which translates into a significant economic burden for patients. Warfarin prescriptions did not significantly impact total health care costs, though caution is advised to minimize hemorrhagic events.