P782 Comparison of accelerated and standard infliximab induction regimens in Acute Severe Ulcerative Colitis using propensity score: A retrospective multicenter study in a Chinese cohort

Abstract

Abstract Background The optimal regimen of infliximab salvage in acute severe ulcerative colitis (ASUC) patients remains controversial. This retrospective multicenter study aimed to compare accelerated and standard infliximab induction in a Chinese cohort of ASUC patients, and to explore risk factors associated with poor prognosis. Methods Data were collected retrospectively from steroid-refractory ASUC patients who received infliximab induction as rescue therapy at seven tertiary centers across China. Accelerated infliximab induction was defined as receiving two doses of infliximab on or before day 13 and/or receiving intensified doses of ≥ 7.5 mg/kg. Outcomes including colectomy and clinical remission (Mayo score ≤ 2 and every subscore ≤ 1 at day 14) rates were compared using propensity score adjustment for potential confounders. The variables in propensity score model was determined by logistic regression analysis for accelerated induction. Results A total of 76 patients were included: 29 received standard induction and 47 received accelerated induction. The overall disease severity was significantly higher in patients of accelerated group (Table). The 30-day colectomy rates did not differ between two groups (4.3% vs. 0%, P=0.522). However, the accelerated group had a higher 90-day colectomy rate (17.8% vs. 0%, P=0.019) and lower clinical remission rate (27.7% vs. 65.5%, P=0.001). (Figure. A) After adjusting with propensity score and institution, there was no significant difference in colectomy (P=0.20) or no clinical remission (P=0.48) hazards. Dose-effect curves plotted by restricted cubic splines (adjusted for propensity score and institution) showed decreased colectomy hazard with higher cumulative infliximab dosage within 5 days, while no improvement was observed for increasing cumulative infliximab dosage within 28 days. (Figure. B) Multivariate logistic regression analyses revealed female gender (OR=7.69, 95%CI: 1.96-33.33) and C-reactive protein (CRP) >10 mg/L at infliximab initiation (OR=5.00, 95%CI: 1.27-24.34) as independent risk factors for no clinical remission. (Figure. C) Conclusion After adjusting for confounders, there were no significant differences in colectomy or clinical remission rates between accelerated and standard infliximab induction among steroid-refractory ASUC patients. Elevated CRP at infliximab initiation indicated more intensive treatment or earlier surgery to be considered. And it would be better to give early intensified dosage within 5 days if needed.