Background and purpose: Antiplatelet therapy is key for preventing thrombotic events after transient ischemic attack or ischemic stroke. Although the role of aspirin is well established, there is emerging evidence for the role of short-term dual antiplatelet therapy (DAPT) in preventing recurrent stroke.
Methods: We conducted a systematic review and study-level meta-analyses of randomized controlled trials comparing outcomes of early initiation of short-term DAPT (aspirin+P2Y12 inhibitor for up to 3 months) versus aspirin alone in patients with acute stroke or transient ischemic attack. Primary efficacy outcome was risk of recurrent stroke and primary safety outcome was incidence of major bleeding. Secondary outcomes studied were risk of any ischemic stroke, hemorrhagic stroke, major adverse cardiovascular events, and all-cause death. Pooled risk ratios (RRs) and CIs were calculated using a random-effects model.
Results: Four trials with a total of 21 459 patients were included. As compared to aspirin alone, DAPT had a lower risk of recurrent stroke (RR, 0.76 [95% CI, 0.68–0.83]; P<0.001; I2=0%) but a higher risk of major bleeding events (RR, 2.22 [95% CI, 1.14–4.34], P=0.02, I2=46.5%). Patients receiving DAPT had a lower risk of major adverse cardiovascular events (RR, 0.76 [95% CI, 0.69–0.84], P<0.001, I2=0%) and recurrent ischemic events (RR, 0.74 [95% CI, 0.67–0.82], P<0.001, I2=0%).
Conclusions: As compared to aspirin alone, short-term DAPT within 24 hours of high-risk transient ischemic attack or mild-moderate ischemic stroke reduces the risk of recurrent stroke at the expense of higher risk of major bleeding.
Keywords: aspirin; hemorrhage; incidence; ischemic attack, transient; ischemic stroke.