根據一項最新研究發現：當用于減少大腦動脈不完全阻塞患者血液凝結的時候，阿司匹林與華法令共同應用的副作用較少。

阿司匹林和華法令用于降低那些顱內血管狹窄患者腦卒中的風險已經長達數十年，但是醫生沒有證據在這兩種方法中進行選擇。在這項叫做“華法令和阿司匹林治療癥狀性顱內血管疾病的臨床試驗”的最新研究中，59個美國醫療中心的研究人員在總計569例患者中比較了每日使用1300毫克阿司匹林與華法令平均達1.8年期間的效果。所有患者顱內大動脈阻塞比例超過50％，在開始治療的90天之內，經歷了腦短暫性缺血發作或者非致殘的腦卒中發作。

研究人員發現，不考慮患者所接受的治療，大約22％患者繼發缺血性腦卒中、腦出血或者由于其它血管相關疾病而死亡。但是，所有原因導致的大出血和死亡率在那些接受華法令治療的患者(8.3%出血大出血；9.7%死亡)顯著高于接受阿司匹林治療的患者(3.2%出血；4.3%死亡)。根據這些結果，考慮到給予華法令患者的安全性，臨床試驗患者的入選比計劃提前終止。

“這項試驗的結果只與顱內血管狹窄的患者相關。”主持這項試驗Emory大學的Marc I.Chimowitz博士解釋說。因為與阿司匹林相比，華法令價格更貴治療更復雜，如果不使用華法令預防與其相關的出血并發癥，根據Chimowitz博士估計，每年將為美國節約200萬美元。

研究人員指出：臨床試驗凸顯示了這樣一個事實，即顱內血管狹窄患者患腦卒中的風險特別高，需要更好的治療方法。他們的研究結果發表在2005年3月31日的《新英格蘭醫學期刊》。
 
 
Aspirin vs Warfarin to Reduce Stroke Risk
 
Aspirin works as well as warfarin and has fewer side effects when used to reduce blood clotting in patients with partial blockage of arteries in the brain, according to a new study.

Both aspirin and warfarin have been used for decades to reduce the risk of stroke in patients with the condition known as intracranial stenosis, but doctors have had no evidence for choosing one therapy over the other. In the new study, called the Warfarin Aspirin Symptomatic Intracranial Disease (WASID) trial, investigators at 59 U.S. medical centers compared warfarin to 1,300 mg per day of aspirin in a total of 569 patients for an average of 1.8 years. All the patients had a greater-than-50% blockage of a major intracranial artery and had experienced a transient ischemic attack (TIA) or nondisabling stroke within 90 days of the start of the study.

Investigators found that about 22% of patients had a subsequent ischemic stroke, brain hemorrhage, or death from other blood-vessel-related causes, regardless of which therapy they received. However, the rates of major hemorrhage and death from all causes were significantly higher in those patients treated with warfarin (8.3% for major hemorrhage and 9.7% for death) than those treated with aspirin (3.2% for hemorrhage and 4.3% for death). Based on these results, enrollment in the trial was terminated earlier than planned because of concern for the safety of patients given warfarin.

“The results of this study are only relevant to people with intracranial stenosis,” explained Dr. Marc I. Chimowitz, of Emory University (Atlanta, GA, USA), who led the trial. Since warfarin is a more expensive and complicated therapy than aspirin, not using warfarin and preventing the bleeding complications associated with it would save more than U.S.$20 million a year in the United States alone, estimated Dr. Chimowitz.

The trial underscored the fact that patients with intracranial stenosis are at particularly high risk for stroke and that better therapies are needed, noted the investigators. Their results were published in the March 31, 2005, issue of The New England Journal of Medicine.