VANCOUVER, Sept. 7 (Xinhua) -- A combination of aspirin and clopidogrel, both common blood thinners, does not prevent recurrence of a common type of stroke, and may even pose serious risks, according to an international team of scientists.
Combining aspirin and clopidogrel (known commercially as Plavix) was thought to hold promise in preventing recurring of lacunar strokes by reducing the formation of clots in arteries supplying the brain.
Lacunar strokes, caused by narrowing of small blood vessels, are also known as small subcortical strokes, which account for about 25 percent of ischemic strokes.
However, in a study published at the end of last month, scientists found the two-drug combination did not significantly reduce the risk of recurrence of stroke, and evidently increased the risk of bleeding and death, compared to aspirin alone or aspirin combined with a placebo.
The study involved 3,020 patients from 82 sites in North America, Latin America, and Spain who were followed for several years, and the result was published in the New England Journal of Medicine.
"Previous randomized trials assessing the effect of clopidogrel alongside aspirin did not show an overall increase in mortality, so our results are a bit surprising," said Oscar Benavente, lead author of the study and professor of neurology from the University of British Columbia.
"The results of our research support the current guidelines for secondary stroke prevention: the use of either aspirin or clopidogrel, or the approved combination therapy of aspirin and dipyridamole (known commercially as Persantine)," Benavente said.