와파린, 출혈성 뇌졸중 위험 증가

와파린, 출혈성 뇌졸중 위험

환자대상 분석 10년간 발생률 3.2명증가

항응고제 와파린이 출혈성 뇌졸중 위험을 증가시킬 수 있다는 연구결과가 나왔다. 미국 신시내티 대학 의과대학 신경과전문의 매슈 플래허티 박사는 1998-1999년 사이에 최초의 뇌출혈로 입원한 환자들을 대상으로 실시한 조사분석 결과 와파린과 관련된 출혈성 뇌졸중 발생률이 1988년의 10만명당 0.8명에서 1999년에는 4.4명으로 크게 늘어났다고 밝혔다. 특히 80세 이상 노인들의 경우는 1988년의 10만명당 2.5명에서 1999년에는 무려 45.9명으로 급증한 것으로 나타났다.

플래허티 박사는 와파린은 뇌혈관이 막혀 발생하는 허혈성 뇌졸중 예방에는 매우 효과적이지만 출혈위험을 수반하기 때문에 뇌혈관이 터져 일어나는 출혈성 뇌졸중 위험을 증가시킨다면서 대부분 환자의 경우 와파린의 이익이 이러한 위험을 상쇄하고도 남는다고 밝혔다. 심방세동이란 심장의 윗부분인 두 심방이 정상적으로 박동하지 못하고 박동이 엄청나게 빨라져 가늘게 떠는 상태가 되는 현상으로 이로 인해 심방에 혈전이 형성되고 그 조각이 떨어져 나가 돌다 뇌혈관을 막으면 허혈성 뇌졸중으로 이어지게 된다.이 연구결과는 '신경학(Neurology)' 최신호에 실렸다. <기사원문> SUNDAY, Jan. 11 (HealthDayNews) -- Warfarin is an anticoagulant -- or "blood thinner" -- that's frequently prescribed for people with atrial fibrillation. An estimated 2.2 million Americans have the cardiac condition, which causes the heart's two upper chambers to flutter, rather than beat efficiently. This leaves people vulnerable to a blood clot in the brain that can result in an ischemic stroke, the most common type of stroke. That's where warfarin comes in -- helping to prevent those clots. But, ironically, as use of warfarin has risen in recent years, so has the number of another type of stroke called hemorrhagic stroke, which occurs when a blood vessel ruptures in the brain. That doesn't mean that warfarin should be abandoned -- far from it, experts say. "Decisions about warfarin use should be made by patients after discussion with their doctor," said Dr. Matthew Flaherty, a University of Cincinnati neurologist who led a study published last year in the journal Neurology about the rising rate of brain hemorrhages linked to anticoagulants. The study looked at medical data from people in the Cincinnati area who had been hospitalized with a first-time brain hemorrhage in the years 1988, 1993-94 and 1999. It found that the annual rate of hemorrhagic stroke linked to warfarin use was 0.8 cases per 100,000 in 1988. But, that number had risen to 4.4 cases per 100,000 by 1999. When Flaherty and his colleagues dug deeper, however, they found that the rise in the rate of hemorrhagic strokes in people 80 years of age and older was even greater -- from 2.5 per 100,000 in 1988 to 45.9 per 100,000 in 1999. "Warfarin is very effective for preventing ischemic strokes in this setting but carries a risk of bleeding. For most patients, the benefit of warfarin more than offsets the risk," Flaherty said. "One area of concern we expressed based upon our previous data was use of warfarin in elderly persons (those over 80 years old), where the risk of bleeding may be higher," he added. "Since the publication of our paper on this topic in Neurology, an important study was published which compared aspirin to warfarin for stroke prevention in elderly persons with atrial fibrillation. The study showed that warfarin was superior to aspirin, even taking into account bleeding risk. This was reassuring and should make physicians and patients more comfortable using warfarin in this setting." In its guidelines for stroke prevention that were updated in 2006, the American Heart Association noted that clinical trials "have firmly established the value of antithrombotic [anti-clotting] therapies for reducing the risk of stroke in patients with atrial fibrillation." For patients taking warfarin for atrial fibrillation, the heart association recommends following a checklist that includes telling your doctor immediately about unusual bleeding or bruising, alerting other doctors and your dentist about your warfarin use, and keeping in close contact with your doctor. Flaherty also recommended that people taking warfarin routinely undergo a test that measures the blood's ability to clot. It's all about measuring the benefits with the risks, he said. More information To learn more about stroke and stroke prevention, visit the U.S. Food and Drug Administration. SOURCES: Matthew Flaherty, M.D., department of neurology, University of Cincinnati College of Medicine; American Heart Association; Jan. 9, 2007, Neurology; Aug. 11, 2007, The Lancet Last Updated: Jan. 11, 2009

메디코파마뉴스/데일리엠디 김종필기자 (jp1122@nate.com)

기사 입력시간 : 2009-01-13 오전 8:32:47