To compare ischemic stroke (IS) risk between oral anticoagulant (OAC) and no-OAC, and new-oral anticoagulants (NOACs) and vitamin K antagonists (VKAs) in atrial fibrillation (AF) patients with a non-sex-related CHA2DS2-VASc score of 1.
The benefit of OAC in AF patients with a single additional stroke risk factor remains uncertain, and evidence comparing NOACs and VKAs in this intermediate-risk group is limited.
A systematic PubMed search identified studies evaluating stroke prevention in this population. A meta-analysis of four observational studies (six arms) was performed using Mantel-Haenszel methods. Odds ratios with 95% confidence intervals were pooled under fixed- and random-effects models. Tau estimator: DerSimonian-Laird. Heterogeneity was assessed with I² and Cochran’s Q. Publication bias was evaluated using trim-and-fill and fail-safe N. Subgroup analyses were stratified by follow-up duration.
For OAC versus no-OAC, fixed-effect analysis showed a significant reduction in IS risk (OR −0.32; 95% CI −0.45 to −0.18; p < 0.001), whereas random-effects analysis was nonsignificant (OR −0.18; 95% CI −0.56 to 0.20). Subgroup estimates favored OAC at 1.5-year follow-up (OR −0.49) and 2.5-year follow-up (OR −0.31). For NOAC versus VKA, both fixed-effect (OR −0.05) and random-effect (OR −0.18) analyses were non-significant, with similar findings at 1-year (OR 0.50; 95% CI 0.19–1.33) and 2-year (OR 0.65; 95% CI 0.30–1.38) follow-up. Heterogeneity was low for OAC versus no OAC (I² = 1%) but moderate for NOAC versus VKA (I² = 36%).
In AF patients with a single additional stroke risk factor, OAC may reduce IS risk compared with n-OAC, particularly with longer follow-up. NOACs and VKAs appear similarly effective in this population.