Efficacy and Safety of Early vs Elective Colonoscopy for Acute Lower Gastrointestinal Bleeding

Background & Aims: We performed a large, multicenter, randomized controlled trial to determine the efficacy and safety of early colonoscopy on outcomes of patients with acute lower gastrointestinal bleeding (ALGIB). Methods: We performed an open-label study at 15 hospitals in Japan of 170 patients with ALGIB randomly assigned (1:1) to groups that underwent early colonoscopy (within 24 hours of initial visit to the hospital) or elective colonoscopy (24–96 hours after hospital admission). The primary outcome was identification of stigmata of recent hemorrhage (SRH). Secondary outcomes were rebleeding within 30 days, endoscopic treatment success, need for transfusion, length of stay, thrombotic events within 30 days, death within 30 days, and adverse events. Results: SRH were identified in 17 of 79 patients (21.5%) in the early colonoscopy group vs 17 of 80 patients (21.3%) in the elective colonoscopy group (difference, 0.3; 95% confidence interval, –12.5 to 13.0; P =. 967). Rebleeding within 30 days of hospital admission occurred in 15.3% of patients in the early colonoscopy group and 6.7% of patients in the elective colonoscopy group (difference, 8.6; 95% confidence interval, –1.4 to 18.7); there were no significant differences between groups in successful endoscopic treatment rate, transfusion rate, length of stay, thrombotic events, or death within 30 days. The adverse event of hemorrhagic shock occurred during bowel preparation in no patient in the early group vs 2 patients (2.5%) in the elective colonoscopy group. Conclusions: In a randomized controlled study, we found that colonoscopy within 24 hours after hospital admission did not increase SRH or reduce rebleeding compared with colonoscopy at 24–96 hours in patients with ALGIB. ClinicalTrials.gov, Numbers: UMIN000021129 and NCT03098173