Meta-regression to identify patients deriving the greatest benefit from dual antiplatelet therapy after stroke or transient ischemic attack without thrombolytic or thrombectomy treatment

The patient's profile drawing the greatest benefit from dual antiplatelet therapy (DAPT) after a noncardioembolic, ischemic cerebrovascular event is not well characterized. Aim of this metaregression analysis was to compare DAPT versus single antiplatelet therapy (SAPT) in patients with stroke or transient ischemic attack (TIA). We searched randomized trials evaluating clinical outcome with aspirin plus a P2Y12 inhibitor versus SAPT in patients with noncardioembolic stroke or TIA. Primary end point was the incidence of recurrent stroke; safety outcome measure was major bleeding. Eleven trials were included in the analysis, enrolling 24,175 patients treated with DAPT (aspirin plus clopidogrel, n = 12,074) or SAPT (n = 12,101) after a stroke or TIA event. In the DAPT group the rates of recurrent stroke were lower (7.1% vs 8.8% with SAPT; odds ratios [OR] 0.74, 95% confidence interval 0.62 to 0.88; p = 0.0007) and the incidence of major bleeding was twofold higher (OR 2.01, 1.35 to 3.01; p = 0.0006). Metaregression indicated a positive correlation between prevention of recurrent stroke by DAPT and baseline stroke severity (p = 0.019), baseline risk profile (p = 0.0001), or prevalence of carotid atherosclerosis (p = 0.040). DAPT was more effective when initiated ≤7 days (OR 0.67, 0.58 to 0.77; p < 0.00001) and used for ≤3 months (OR 0.66, 0.58 to 0.76; p < 0.00001) after the event. In conclusion, in patients with stroke or TIA, the highest benefit of DAPT was observed in patients with higher baseline risk profile, greater stroke severity, or concomitant carotid disease, and when DAPT was initiated early and given for ≤3 months.