Women with AF at Greater Risk of Clots Than Men

Among patients with atrial fibrillation(AF) who are not currently taking theanticoagulant drug warfarin, womenare more likely to form life-threateningblood clots than men, according to theresults of a recent study published inCirculation: Journal of the AmericanHeart Association. The good news forwomen, however, is that they benefitas much as men when taking the drug.

As lead author Margaret C. Fang,MD, MPH, of the University of Californiain San Francisco stated, "ourresults showed consistently that womenwith AF had higher rates of strokethan did men." She also pointed out,however, that "this elevated risk canbe significantly reduced by treatingwomen with AF with warfarin."

Researchers studied 13,559 adultswith AF, 5795 women and 7764 men,over an average of 2.4 years. Duringfollow-up, they identified 394 thromboembolicevents that happenedwhen the patients were not takingwarfarin; the rate for women wasalmost twice that for men (3.5% vs1.8%). Among warfarin users, however,the numbers evened out, withunadjusted rates of thromboembolismat 1.5% in women and 1.2% in men.