Whether antithrombotic agent (ATA) usage increases the risk of gastric post-endoscopic submucosal dissection (ESD) bleeding remains controversial. The aim of this study was to elucidate the effects of usage, type, and cessation timing of ATA on post-ESD bleeding. A total of 4775 early gastric cancer patients undergoing ESD were analyzed; 1:3 propensity score matching between ATA and non-ATA groups resulted in 318 and 767 matched patients in each group, respectively. Outcomes were compared between the two groups using a generalized estimating equation method. After matching, post-ESD bleeding rates in ATA users and non-users were 9.1% and 4.2%, respectively (p = 0.001). In multivariable analysis, ATA usage was independently associated with an increased risk of post-ESD bleeding (adjusted odds ratio: 2.28, 95% confidence interval: 1.34-3.86). Both the continued or insufficient cessation groups and the sufficient cessation group had an increased incidence of post-ESD bleeding compared to their matched controls (12.5% versus 5.2%, p = 0.048; 8.1% versus 3.9%, p = 0.014). Post-ESD bleeding rates in antiplatelet agent users were significantly higher than those of their matched controls (8.3% versus 4.2%, p = 0.010). ATA usage increased the risk of post-ESD bleeding even after its sufficient cessation. Careful observation after ESD is required regardless of the cessation status of ATA.
Keywords: anticoagulants; antiplatelets; endoscopic submucosal dissection; postoperative hemorrhage.