P254 Outcomes of endoscopic and histologic remission in ulcerative colitis under advanced therapy

Abstract

Abstract Background Current expert-based recommendations suggest that clinical and endoscopic remission should be pursued as treatment targets in ulcerative colitis (UC). However, combined endoscopic and histologic remission may be associated with improved outcomes. Methods Retrospective single-center cohort study including consecutive patients with UC under advanced therapy (biologics and small molecules) with endoscopic and histologic evaluation. We evaluated the rates of hospitalization, surgery, steroid-free remission, and treatment discontinuation after 1-year of follow-up according to the type of remission. Endoscopic remission was defined as a Mayo endoscopic subscore of 0. Histologic remission was defined as the absence of ulcers, erosions and neutrophils in the lamina propria. Results One hundred and six patients were included. Thirty-five patients (33.0%) achieved combined endoscopic and histologic remission, 21 patients (19.8%) endoscopic but not histologic remission and 50 patients (47.2%) did not achieve endoscopic remission. At the end of 1-year, 85 patients (79.4%) achieved steroid-free remission, 14 (13.0%) required hospitalization, 4 (3.7%) surgery, 15 (14.1%) discontinued treatment. A compound outcome was reached by 31 (29.2%) patients. In multivariate analysis including age at diagnosis, age at biologic, type of advanced treatment, disease duration, immunomodulation, previous biologic exposure and type of remission, only the type of remission was associated with a lower chance of reaching any unfavourable outcome (reference no remission) - combined endoscopic and histologic remission (OR 0.162 95%CI 0.05-0.528, P=0.003) and isolated endoscopic remission (OR 0.286 95%CI 0.084-0.971, P=0.045). Kaplan-Meier analysis showed longer outcome-free survival in patients with combined endoscopic and histologic remission. Conclusion Achieving combined endoscopic and histologic remission is associated with better clinical outcomes after 1 year of advanced treatment compared to no remission. However, we could not confirm a significant advantage of combined endoscopic and histologic remission over endoscopic remission alone.