P725 Predictive factors for biologic therapy initiation after ileal pouch-anal anastomosis

Abstract

Abstract Background Patients with ulcerative colitis (UC) undergoing proctocolectomy and Ileal Pouch-Anal Anastomosis (IPAA) frequently develop long-term complications, such as chronic pouchitis and Crohn’s-like disease of the pouch. These may eventually require biologic therapy. We aimed to identify peri-operative predictors for biologic therapy after IPAA. Methods All patients after IPAA followed at Rabin Medical Center pouch clinic and consenting to prospective observational follow up were included. Patients undergoing IPAA due to familial adenomatous polyposis (FAP) and those with ileostomy were excluded. Primary outcome was the initiation of biologic therapy after IPAA. We used Cox proportional hazard models to evaluate the following potential predictors: gender, race, smoking status, BMI category, UC duration until surgery, surgery indication, immediate post-operative complications (bowel obstruction, infection and leakage), and pre-operative treatment with 5-ASA, steroids, immunomodulators, and biologic therapy. Results Out of 174 patients in our cohort, 18 were excluded due to FAP and 8 due to ileostomy, leaving 148 for analysis. Prior to IPAA, 52 patients (35%) were treated with biologic therapy. Median follow-up from ileostomy closure to last documented visit was 15.14 years. During this period, 32 patients (21.6%) initiated biologic therapy, including 18 with adalimumab (12.2%), 10 with infliximab (6.7%), 2 with ustekinumab (1.3%), 1 with golimumab (0.6%), and 1 with vedolizumab (0.6%). Median time-to biologic therapy initiation was 10.1 years (IQR 10.0). Significant hazard ratios (HR) for biologic therapy initiation were pre-operative treatment with biologic therapy (HR 4.8, 95% CI; 2.3-10, p<0.001); Arab descent (HR 4.7, 95% CI; 1.6-14, p=0.005); pre-operative treatment with immunomodulators (HR 3.0, 95% CI; 1.3-7, p=0.011); UC duration of less than 10 years before ileostomy closure (HR 2.7, 95% CI; 1.2-6.3, p=0.02); past smoking status (HR 2.6, 95% CI; 1.22-5.7, p=0.013); and immediate post-operative complications (HR 2.0, 95% CI; 1.0-4.1, p=0.05). None of the patients undergoing IPAA due to dysplasia (n=27), required biologic therapy. Conclusion Pre-operative treatment with either biologic therapy or immunomodulators, Arab descent, short disease duration prior to IPAA, past smoking status, and post-operative complications were significant predictors of biologic therapy initiation post-IPAA. Patients with these risk factors may benefit from closer post-operative follow-up and earlier initiation of biologic therapy.