T1295 Development of a Nomogram for Prediction of Pouch Failure in Ulcerative Colitis (UC) Patients With Restorative Proctocolectomy

Abstract

Background: A proportion of UC pts with ileal pouch-anal anastomoosis (IPAA) develop pouch failure. Information on factors that may reliably predict pouch failure for pts who have pouch related symptoms or disorders requiring referral to a specialized care is minimal. Aim: To develop and internally validate a nomogram to predict the probability of pouch failure. Methods: The study cohort included all eligible UC patients with IPAA at Pouchitis Clinic from 2002 to 2009. Inclusion criteria were patients 1) having underlying IBD; 2) regularly monitored at the Pouchitis Clinic. 36 demographic and clinical variables were prospectively collected. Multivariable accelerated failure time regressionmodel was developed to predict pouch failure, defined as pouch excision or permanent diversion. Discrimination and calibration of the model were assessed following bootstrapping methods for correcting optimism, and the model was presented as a nomogram. Results: 921 patients were included for the model. The mean age for this cohort was 45.5 years old. The mean follow-up at the Pouchitis Clinic was 5.8 years. Kaplan-Meier plot showed that the probabilities for pouch retention are 0.939, 0.916 and 0.907 at 3, 5 and 7 years, respectively. The predictor variables which were included in the nomogram were smoking, duration of the pouch, preoperative diagnosis, pouch diagnosis at the first Pouchitis Clinic visit and post-op use of biologics (Figure 1). The concordance index was 0.824. Conclusions: The nomogram model appeared to predict pouch failure reasonably well with satisfactory concordance index and calibration curve. The nomogram is readily applicable for clinical practice in pouch patients.