Temporal trends in the use of anticoagulants among older adults with atrial fibrillation

Background: Several recent randomized clinical trials have demonstrated tha t warfarin sodium treatment, and to a lesser extent aspirin, reduces risk o f stroke and death compared with placebo in persons with atrial fibrillatio n. Insufficient documentation exists on the extent to which the use of thes e therapies following trial publications has continued to increase in the e lderly with atrial fibrillation. Methods: We used data from the Cardiovascular Health Study, a study of 5888 community-dwelling adults aged 65 years or older, to determine the prevale nce of warfarin and aspirin use in persons with electrocardiogram-identifie d atrial fibrillation. Electrocardiogram examinations were conducted at bas eline from 1989 through 1990, and at 6 subsequent annual examinations throu gh 1995-1996. Medication data were collected by inventory methods at each e xamination. Temporal change in use of anticoagulants was analyzed by compar ing percentage use in 1990 to use in each year through 1996. Results: The use of warfarin increased 4-fold from 13% in 1990 to 50% in 19 96 among participants with prevalent atrial fibrillation (P < .001). Daily use of aspirin did not increase over time. Participants younger than 80 yea rs were 4 times more likely to use warfarin in 1996 (P < .001) than those 8 0 years and older. Use of aspirin did not vary significantly with age. Conclusions: Warfarin use in community-dwelling elderly persons with electr ocardiogram-documented atrial fibrillation increased steadily following the first publication of its treatment benefit, reaching 50% by 1996. In contr ast, use of aspirin was unchanged during this same period. Continued effort s to promote appropriate antil coagulation therapy to physicians and their patients may still be needed.