ABSTRACT
Early clinical trials comparing acetylsalicylic acid (ASA), or aspirin, with the combination of ASA and dipyridamole (DP) in stroke prevention showed no additional benefits for the combination over those for ASA alone (Bousser et al., 1983; Guiraud-Chaumeil et al., 1982; The American-Canadian Co-operative Study Group, 1985). However, these studies were in relatively small numbers of patients, which were too small to detect potential differences. To compare the effects of dipyridamole or ASA with those of the ASA/DP combination in a study powered to detect statistically significant differences in a conclusive way, the European Stroke Prevention Study 2 (ESPS-2) Study Group initiated and recently completed a large, double-blind, randomized clinical trial. The results of this trial, published in 1996, clearly show the advantage of the ASA/DP combination over ASA alone (Diener et al., 1996).
