Risk factors associated with post-extraction bleeding in patients on warfarin or direct-acting oral anticoagulants: a retrospective cohort study

Purpose The purpose of this study was to investigate the risk factors associated with post-extraction persistent bleeding in patients on warfarin or direct-acting oral anticoagulants (DOACs) and the ability of risk scores to predict post-extraction bleeding. Methods Three hundred ninety-one patients taking warfarin or DOACs underwent tooth extractions. Various risk factors for post-extraction bleeding, including number of tooth extraction, with antiplatelet therapy, and risk scores, were investigated by univariate and multivariate analyses. A post-extraction bleeding was classified into grades 1-3. Results The incidence of post-extraction bleeding was 26.8% (77 out of 287 patients; grade 1: 63, grade 2:14) in patients taking warfarin, and 26.0% (27 out of 104 patients; grade 1: 20, grade 2:7) in patients taking warfarin DOACs. Multivariate analyses showed that multiple teeth extractions and HAS-BLED scores (above 3 points) in patients taking warfarin, and only multiple teeth extractions in patients taking DOAC, were significantly associated with post-extraction bleeding, respectively. Conclusion Most of the post-extraction bleedings were grade 1, which can be stopped by eligibly pressing gauze by surgeons. If patients taking anticoagulants are scheduled to undergo multiple teeth extractions or their HAS-BLED score are above 3 points (if warfarin), we recommend informing patients risk of post-extraction bleeding before operation, taking carefully hemostasis, and instructing patients to bite down accurately on the gauze for longer than usual.