Background: We evaluated long-term incidence and identified risk factors of colectomy in pre-biologics and biologics eras for treatment of ulcerative colitis.

Methods: After IRB approval, using data obtained from the Régie d'assurance maladie du Québec, we defined two cohorts: pre-biologics (1998-2004) and biologics (2005-2011) eras. Patients with inflammatory bowel disease or colectomy 1 year prior to first diagnosis of ulcerative colitis were excluded. Multivariate logistic regression model compared patient baseline characteristics. Kaplan-Meier curves displayed unadjusted time to event. Cox proportional hazards models were used to compare adjusted colectomy and mortality rates, respectively.

Results: In pre-biologics and biologics eras, 335/2829 and 314/3313 patients, respectively, underwent colectomy. Median follow-up (first and third quartiles) was similar (p = 0.206). Incidence rates for colectomy were 36.08/1000 and 29.99/1000 patient years. Unadjusted rate of colectomy was higher in pre-biologics era (p = 0.004). Predictors of colectomy included anemia (1.66; 1.38-2.01), gastrointestinal hospitalizations (1.24; 1.04-1.47), congestive heart failure (2.08; 1.27-3.40), and male gender (1.47; 1.26-1.72). Mortality was 8.06 and 3.18% in pre-biologics and biologics eras. After adjusting for potential confounders, age (1.08; 1.05-1.12) and urgent colectomy (5.65; 2.19-14.54) remained associated with increased mortality hazard.

Conclusion: Incidence of colectomy decreased after introduction of biologics. Risk factors for colectomy were gastrointestinal hospitalizations, anemia, male gender, and congestive heart failure. Emergent surgery and age were predictors of mortality.