The Role of Antiplatelet Medications in Angiogram-Negative Subarachnoid Hemorrhage

Abstract BACKGROUND: The use of antiplatelet medications has greatly expanded and this has been associated with an increased rate of complications after aneurysmal subarachnoid hemorrhage (SAH). The influence of antiplatelet medications on outcomes after non-aneurysmal SAH is unknown. OBJECTIVE: To analyze the frequency and impact on outcome of antiplatelet medication use among patients with angiogram-negative SAH. METHODS: An analysis of patients within the Columbia University SAH Outcomes Project database was performed. All patients who underwent catheter cerebral angiography after presenting with nontraumatic SAH between 1996 and 2013 were included. Outcomes were assessed by using the modified Rankin Scale. RESULTS: A total of 1351 patients underwent catheter angiography for evaluation of SAH. Of these, 173 (13%) were designated angiogram-negative. The fraction of patients presenting with angiogram-negative SAH as well as the frequency of antiplatelet use among these patients significantly increased during the study period. Antiplatelet use was more commonly associated with angiogram-negative SAH than with angiogram-positive SAH (27% vs 14%, P = .001). At 14 days after presentation, poor outcome was significantly more frequent among patients who took antiplatelet agents than among those who did not (38% vs 20%, P = .017). This effect was also seen after multivariate analysis (odds ratio, 2.58; P = .034), although no difference was observed by 12 months (P > .05). CONCLUSION: Antiplatelet medication use is associated with poor early, but not late, outcomes after angiogram-negative SAH. Corresponding increased rates of antiplatelet medication use and angiogram-negative SAH may be related. Additional studies are needed to confirm this association.