Aspirin appears to reduce stroke severity

Individuals who had taken at least one aspirin in the week before suffering an ischemic stroke had milder strokes than people who had not taken aspirin, according to a report in the December issue of Stroke: Journal of the American Heart Association.

The study compared stroke severity of aspirin users and nonusers with data from the Trial of Org 10172 in Acute Stroke Treatment, a multicenter, randomized, placebo-controlled, double blind clinical trial in which patients were admitted from 1990-1996.

Among patients whose strokes were caused by a blockage of blood flow in the brain (ischemic stroke), researchers compared stroke severity between those who had been taking aspirin and those who had not. Of 1,275 patients in the study, 40% reported aspirin use during the week before their stroke. Researchers found more strokes among the aspirin users, but their severity was significantly lower than strokes among nonusers.

Using the National Institutes of Health Stroke Scale, 50% of aspirin users had mild strokes, compared with 43% of nonusers; only 10% of aspirin users had severe strokes, compared with 15% of nonusers. On the Supplemental Motor Examination ranking that measures the severity of muscle weakness in arms and legs, 56% of aspirin users had mild strokes, compared with 49% of nonusers; 20% of aspirin users had severe strokes, compared with 24% of nonusers.

Several different mechanisms factor in aspirin's protective effect, say the researchers, including its antiplatelet effect, which may improve blood circulation in brain; its antioxidant properties, which may reduce oxidative tissue damage; or some other possible anti-inflammatory, neuroprotective effect, which at this time is still under investigation.

"Aspirin has a rich pharmacology, some of which is still being elucidated," says Janet Wilterdink, of the department of neurology at Brown Medical School in Providence, Rhode Island. "I believe that a combination of all these mechanisms has the potential to play a significant role in aspirin's beneficial effect."