Outcomes and performance of risk scores in acute lower gastrointestinal bleeding.

Background and Aim: Treatment of acute lower gastrointestinal bleeding (LGIB) remains problematic, and clinical data is limited compared to that of upper GIB. This study aimed to describe the clinical outcomes and predictors of rebleeding and validate the performance of proposed scoring systems in patients with acute overt LGIB. Methods: Patients with LGIB who underwent colonoscopies between 2013 and 2018 were retrospectively reviewed. Overt LGIB patients who presented within 72 h after bleeding onset were included. Demographics, comorbidities, initial management, endoscopic finding, and treatment outcomes were collected. Factors associated with rebleeding were explored, and the performance of Oakland, NOBLAD, and Strate scores regarding mortality and rebleeding were validated. Results: A total of 537 patients from 3402 (age 72 years, 63-80) were included. Of this, 53% took antithrombotic agents and 59% required red cell transfusion, with a median of 4 red cell units. The most common diagnoses were diverticular bleeding (31.3%) and colorectal polyp/cancer (28.9%). The median time to colonoscopy was 2.3 days, and 80.3% of patients did not receive any hemostatic intervention. The 30-day mortality and rebleeding were 2.6% and 18.3%, respectively. Patients with radiation proctitis, angioectasia, diverticulosis and using dual antiplatelet drugs were associated with recurrent bleeding. The risk scores showed low performance in predicting recurrent bleeding and mortality. Conclusion: Acute, overt LGIB was common among elders with comorbidities. The rebleeding risk was mostly linked to underlying lesions and the use of antiplatelet drugs. The performance of current risk stratification scores remains unsatisfactory and requires further development.