Single vs. dual antiplatelet therapy before DOAC initiation in acute ischemic stroke with atrial fibrillation: a retrospective cohort study
TL;DR
DAPT prior to DOAC initiation was associated with higher 90-day favorable functional outcome without excess bleeding risk, but this association was not independent of baseline stroke severity after multivariable adjustment, suggesting that the crude benefit was largely attributable to selection bias rather than a true therapeutic advantage of DAPT.
Abstract
Background The optimal antiplatelet bridging strategy before initiating direct oral anticoagulants (DOACs) in patients with acute ischemic stroke (AIS) and non-valvular atrial fibrillation (NVAF) remains uncertain. Methods This single-center retrospective cohort study included 120 patients with AIS and NVAF who received antiplatelet therapy prior to DOAC initiation. Patients were stratified by regimen: single antiplatelet therapy (SAPT, n = 48) or dual antiplatelet therapy (DAPT, n = 72). Primary outcomes included early neurological improvement (≥2-point NIHSS reduction), early neurological deterioration (≥4-point NIHSS increase or death within 48 h), and in-hospital bleeding. Secondary outcomes were 90-day favorable functional outcome (modified Rankin Scale 0–2), 90-day excellent outcome (mRS 0–1), and ordinal mRS shift. Multivariate logistic regression identified independent predictors. Ordinal logistic regression was used for mRS shift analysis. Results Baseline characteristics were comparable between groups, with no significant differences in baseline NIHSS score (median 4.00 vs. 2.00, p = 0.136) or mRS score (median 3.00 vs. 3.00, p = 0.435). No significant differences were observed in early neurological improvement (39.6% vs. 37.5%, p = 0.969), early deterioration (4.2% vs. 0%, p = 0.158), or bleeding events (6.2% vs. 1.4%, p = 0.301). In unadjusted analysis, DAPT demonstrated higher 90-day favorable outcome (90.3% vs. 75.0%, p = 0.046). However, after multivariable adjustment, DAPT was not independently associated with mRS 0–2 (adjusted OR 2.40, 95% CI 0.62–10.06, p = 0.211), mRS 0–1 (adjusted OR 1.18, 95% CI 0.43–3.14, p = 0.739), or ordinal mRS shift (adjusted common OR 0.70, 95% CI 0.34–1.44, p = 0.336). Baseline NIHSS score independently predicted all outcomes (p < 0.001 for all). Conclusion In unadjusted analysis, DAPT prior to DOAC initiation was associated with higher 90-day favorable functional outcome without excess bleeding risk. However, this association was not independent of baseline stroke severity after multivariable adjustment, suggesting that the crude benefit was largely attributable to selection bias rather than a true therapeutic advantage of DAPT. The current data do not support the superiority of DAPT over SAPT. Baseline NIHSS score independently predicted both short-term and long-term outcomes. These hypothesis-generating findings warrant confirmation in adequately powered prospective randomized trials.