Antithrombotic therapy for stroke prevention among Medicare beneficiaries hospitalized in Alaska with atrial fibrillation.

Although warfarin therapy reduces the risk of stroke among patients with atrial fibrillation (AF), the risk of hemorrhagic complications and other concerns may make clinicians reluctant to prescribe this treatment for elderly patients. Aspirin is a lower-risk alternative to warfarin but is also less effective. This study examines the use of antithrombotic therapy with warfarin or aspirin at hospital discharge among 182 Medicare beneficiaries 65 or older with chronic AF who were admitted to nine Alaska hospitals during 1996. Sixty-five percent of patients without contraindications were discharged on warfarin, and an additional 16% received aspirin. The rate of anticoagulation with warfarin was much higher among patients aged 65-74 (95%) than among those 75 or older (45%). The relatively low rate of warfarin use for very elderly patients may represent an opportunity to improve care. Although these patients have the highest risk of hemorrhagic complications, they also have the greatest potential to benefit from anticoagulation.