[Risk factors of delayed bleeding after colonoscopic polypectomy: case-control study].

BACKGROUND/AIMS Colonoscopic polypectomy is a valuable procedure for preventing colorectal cancer, but is not without complications. Delayed bleeding after colonoscopic polypectomy is a rare, but serious complication. The aim of this study was to identify risk factors of delayed bleeding after colonoscopic polypectomy. METHODS A retrospective case-control study was conducted in a single university hospital. Forty cases and 120 controls were included. Data collected included comorbidity, use of antiplatelet agents, size and number of resected polyps, histology and gross morphology of resected polyps, endoscopist's experience, resection method, use of sedation, and use of prophylactic hemostasis. RESULTS In univariate analysis, size, histology and number of resected polyps, endoscopist's experience, resection method and use of prophylactic hemostasis were significant risk factors for delayed bleeding after colonoscopic polypectomy. In multivariate analysis, risk of delayed bleeding increased by 11.6% for every 1 mm increase in resected polyp diameter (OR, 1.116; 95% CI 1.041-1.198; p=0.002). Number of resected polyps (OR, 1.364; 95% CI, 1.113-1.671; p=0.003) and endoscopist's experience (OR, 6.301; 95% CI, 2.022-19.637; p=0.002) were significant risk factors for delayed bleeding after colonoscopic polypectomy. CONCLUSIONS Size and numbers of resected polyps, and endoscopist's experience were independent risk factors for delayed bleeding after colonoscopic polypectomy. More caution would be necessary when removing polyps with these factors.