Persantine Aspirin Trial in cerebral ischemia. Part II: Endpoint results. The American-Canadian Co-Operative Study group.

The Persantine Aspirin Trial focused on the question of whether the administration of the combination of aspirin and dipyridamole (Persantine) would result in a lower incidence of cerebral or retinal infarction or death than the administration of aspirin alone for persons with a history of recent carotid territory transient ischemic attacks (TIAs). Fifteen centers in the United States and Canada participated and 890 individuals were admitted and randomly allocated to either aspirin (325 mg) plus placebo or aspirin (325 mg) plus Persantine (75 mg) four times daily. Ninety eight percent of the subjects were followed for at least one year; many were followed for four to five years. The results of life table analysis indicate that the overall endpoint rates for the "aspirin only" and "aspirin plus Persantine" groups are identical. Thus, for TIA patients taking aspirin, the addition of Persantine contributes nothing. There was a clustering of stroke endpoints during the first month after randomization. Deaths from all causes were essentially equally divided between the two treatment groups.