Randomized controlled trial of acetylsalicylic acid in aneurysmal subarachnoid hemorrhage: the MASH Study

Abstract

Background and purpose: A previous systematic review of randomized trials suggested a positive effect of antiplatelet therapy in patients with aneurysmal subarachnoid hemorrhage (SAH). We performed a randomized controlled trial to assess whether acetylsalicylic acid (ASA) reduces the risk of delayed ischemic neurological deficit (DIND) in patients with SAH.

Methods: Criteria for inclusion were aneurysm treatment within 4 days after SAH. Trial medication (14 daily suppositories with 100 mg ASA or placebo) was started within 12 hours after aneurysm treatment. Analysis for the primary outcome event DIND was made according to the "on-treatment" principle and for the secondary outcome measures "poor outcome" and "nonexcellent outcome" according to the "intention-to-treat" principle.

Results: Inclusion was stopped after the second interim analysis, when 161 of the planned 200 patients were included, because by then the chances of a positive effect were negligible. At the final analysis, ASA did not reduce the risk of DIND (hazard ratio, 1.83; 95% CI, 0.85 to 3.9). The relative risk reduction for poor outcome was 21% (relative risk, 0.79; 95% CI, 0.38 to 1.6).

Conclusions: ASA given after aneurysm treatment does not appreciably reduce the occurrence of DIND.