Analysis of post‐extraction bleeding in patients taking antithrombotic therapy using data from the longevity improvement and fair evidence study

BACKGROUND: Several studies have investigated post-extraction bleeding in patients on antithrombotic therapy, but most included a small sample size. OBJECTIVE: This study aimed to analyse post-extraction bleeding in patients on antithrombotic therapy using data from a large database. MATERIALS AND METHODS: Claims data of National Health Insurance and Late-Stage Elderly Healthcare System enrollees who underwent tooth extraction between October 2014 and March 2019 (n = 107 767) in a large multiregional cohort study (Longevity Improvement and Fair Evidence study) were included. Antithrombotic therapy was determined based on the drug codes used at the time of tooth extraction (classified into six groups: no antithrombotic, single antiplatelet, dual antiplatelet, Direct Oral Anticoagulant, warfarin and combined antiplatelet and anticoagulant therapies). The outcome was defined as the presence of "post-extraction bleeding" as a receipt disease name in the same month as tooth extraction. To examine the association between antithrombotic therapy and post-extraction bleeding in detail, multiple logistic regression analysis was performed with post-extraction bleeding as the objective variable; each antithrombotic therapy as the explanatory variable; and age, sex and comorbidities as adjustment variables. RESULTS: Antithrombotic therapy was administered in 14 343 patients (13.3%), and post-extraction bleeding was observed in 419 patients (0.4%). The rate of post-extraction bleeding was significantly lower in the no antithrombotic therapy and single antiplatelet groups than that in the other groups (odds ratio: 2.00-9.02). CONCLUSION: The frequency of post-extraction bleeding is high in patients on anticoagulation or dual antithrombotic therapy. Therefore, careful preparation before extraction is necessary in these patients.