Patients Taking Antithrombotic Medications Present Less Frequently with Ruptured Aneurysms

BACKGROUND: Conflicting findings exist on the protective role of aspirin against aneurysmal subarachnoid hemorrhage (SAH). In this retrospective analysis, we compare the risk of SAH at presentation between patients treated microsurgically who were regularly taking an antithrombotic medication versus those who were not. METHODS: Consecutive patients with solitary aneurysms treated by the senior author using a microsurgical approach were included from a database of patients treated between January 2010 and April 2013 at a tertiary academic medical center. chi(2) and logistic regression analysis were performed, comparing the risk of SAH with antithrombotic use. RESULTS: A total of 347 patients were included in the study, 156 (45%) of whom presented with SAH. A total of 63 patients (18%) were taking an antithrombotic medication (aspirin, 53; clopidogrel, 6; both, 4) and 12 (4%) were on anticoagulation medication. Multivariate analysis was conducted using SAH as the primary outcome and included patient age (odds ratio [OR], 0.99), gender (male, OR, 0.65), tobacco use (OR, 1.43), alcohol use (OR, 1.02), coronary artery disease (OR, 1.84), diabetes (OR, 1.03), hypertension (OR 0.91), and posterior circulation location (OR, 1.47). This analysis found that only antithrombotic use (OR, 0.20) was associated with a significantly lower rate of rupture at the time of presentation (P < 0.001). CONCLUSIONS: Patients taking an antithrombotic were less likely to present with ruptured aneurysms. No difference was found for those taking anticoagulants. Patient outcomes did not differ between those on an antithrombotic versus those without. A randomized controlled trial is needed to further investigate the application of antithrombotics for preventing SAH.