Among patients with atrial fibrillation (AF) who are not currently taking the anticoagulant drug warfarin, women are more likely to form life-threatening blood clots than men, according to the results of a recent study published in Circulation: Journal of the American Heart Association. The good news for women, however, is that they benefit as much as men when taking the drug.
As lead author Margaret C. Fang, MD, MPH, of the University of California in San Francisco stated, "our results showed consistently that women with AF had higher rates of stroke than did men." She also pointed out, however, that "this elevated risk can be significantly reduced by treating women with AF with warfarin."
Researchers studied 13,559 adults with AF, 5795 women and 7764 men, over an average of 2.4 years. During follow-up, they identified 394 thromboembolic events that happened when the patients were not taking warfarin; the rate for women was almost twice that for men (3.5% vs 1.8%). Among warfarin users, however, the numbers evened out, with unadjusted rates of thromboembolism at 1.5% in women and 1.2% in men.