Although warfarin therapy reduces stroke incidence in patients with atrial fibrillation, the rate of warfarin use in this population remains low. In 2008, the Medicare Part D program was expanded to pay for medications for Medicare enrollees. UTMB researchers Mukaila A Raji, Matthew Lowery, Yu-Li Lin, Yong-Fang Kuo, Jacques Baillargeon and James S Goodwin examined rates and predictors of warfarin use in Medicare Part D beneficiaries with AF. They found that warfarin use rates vary by patient characteristics and region, with higher rates among residents of the Midwest and among patients seen by cardiologists and PCPs. Preventing stroke-related disability in AF requires implementation of evidence-based initiatives to increase warfarin use.