Dual antiplatelet therapy does not improve outcomes after aneurysmal subarachnoid hemorrhage compared with aspirin monotherapy

Abstract

Background: The pathophysiology of delayed cerebral ischemia (DCI) after aneurysmal subarachnoid hemorrhage (aSAH) may include platelet activation and microthrombi formation. Antiplatelet therapy may reduce the incidence of DCI and improve clinical outcomes after aSAH. This study compared outcomes among aSAH patients receiving aspirin monotherapy versus dual antiplatelet therapy (DAPT).

Methods: Aneurysmal subarachnoid hemorrhage patients treated at a single institution between November 2011 and December 2017 were divided according to whether they received aspirin monotherapy or DAPT after endovascular treatment. Baseline characteristics and outcomes of the groups were compared, including incidences of delayed cerebral ischemia, bleeding complications, symptomatic vasospasm, in-hospital mortality, and functional status 6 months after discharge.

Results: During the study period, 142 patients met study inclusion criteria, of which 123 were treated with aspirin monotherapy (87 %) and 19 were treated with DAPT (13 %). There was no statistically significant difference between the aspirin monotherapy and DAPT groups with respect to incidences of delayed cerebral ischemia (4.9 vs 10.5 %; p = 0.32), symptomatic vasospasm (13.0 vs 15.8 %; p = 0.74), or good clinical outcome at 6-month follow up (73.3 vs 66.7 %; p = 0.56). The DAPT group experienced a higher incidence of in-hospital mortality (21 vs 5.7 %; p = 0.02), but DAPT did not remain independently predictive of this outcome on regression analysis. There was a trend toward a higher bleeding complication rate in the DAPT group (0.8 vs 5.3 %; p = 0.13).

Conclusions: DAPT does not reduce the incidence of DCI or improve outcomes in aSAH patients, and may increase the risk of clinically significant bleeding complications.

Keywords: Aneurysm; Antiplatelet therapy; Delayed cerebral ischemia; Subarachnoid haemorrhage; Vasospasm.