European Stroke Prevention Study. ESPS Group.

We compared the outcomes of 2,500 patients who suffered from previous cerebrovascular disorders (transient ischemic attacks, reversible ischemic neurologic deficits, or completed strokes) treated with acetylsalicylic acid plus dipyridamole or matched placebo and followed for 2 years. Treatment was associated with a 33.5% reduction (p less than 0.001) in the incidence of all end points (deaths from all causes or strokes) by intention-to-treat analysis and a 36.5% reduction (p less than 0.001) by explanatory analysis. End point reduction appeared to be similar in men and women. The effect of treatment was similar regardless of the patients' age, nature of the qualifying cerebrovascular event, site of the responsible lesion, and diastolic blood pressure. Our results demonstrate the efficacy of combined therapy, but the efficacy of acetylsalicylic acid or dipyridamole alone and the most effective acetylsalicylic acid dosage remain in question.