Prolongation of bleeding time and inhibition of platelet aggregation by low-dose acetylsalicylic acid in patients with cerebrovascular disease.

Abstract

Platelet aggregation and bleeding time was measured in 43 cerebrovascular patients participating in a controlled double-blind study of low-dose acetylsalicylic acid. In 19 patients with satisfactory inhibition of the platelet aggregation obtained by 50-70 mg acetylsalicylic acid per day the bleeding time averaged 11.2 min in contrasts to 7.0 min in the placebo group, P < 0.001. Previous findings of platelet inhibition by low-dose acetylsalicyclic acid in patients with cerebrovascular disease were confirmed. The prolongation of the bleeding time demonstrates a significant in vivo effect. The study provides the rationale for clinical evaluations of low-dose acetylsalicylic acid in stroke prophylaxis.