Early Combined Immunosuppression May Be More Effective for Reducing Complications in Isolated Colonic- vs Ileal-Dominant Crohn Disease.

Abstract

We assessed whether differential efficacy of early combined immunosuppression (ECI) in comparison with conventional management (CM) is present in patients with Crohn disease (CD) according to disease location. In this posthoc analysis of the Randomized Evaluation of an Algorithm for Crohn's Treatment trial, the effect of ECI vs CM modified by disease location (isolated-colonic vs ileal-dominant) in terms of time to first complication (hospitalization, surgery, or disease-related complications-presence of a new abscess, fistula, or stricture; serious worsening of disease activity; extraintestinal manifestations) was analyzed using a marginal Cox proportional hazard model to account for cluster randomization. Factors adjusted included practice size, country, and other covariates selected in a backward logistic regression analysis with the first composition as outcome and P < 0.10. Of the 1969 patients with CD, 435 had isolated colonic CD (ECI n = 257, CM n = 178) and 1534 had ileal CD (ECI n = 817, CM n = 717). Over 24 months there was a significant differential impact for ECI vs CM for reducing the risk of a CD-related complication between patients with colonic CD and ileal CD (colonic CD hazard ratio [HR] = 0.51; 95% CI, 0.30-0.85 vs ileal CD HR = 0.79; 95% CI, 0.57-1.10; P = 0.033). No difference was identified between ECI vs CM for reducing the risk of surgery (colonic HR = 0.52 vs ileal HR = 0.74; P = 0.468) or hospitalization (colonic HR = 0.77 vs ileal HR = 0.83; P = 0.806). In this posthoc analysis of the Randomized Evaluation of an Algorithm for Crohn's Treatment trial, symptom-based ECI was associated with greater efficacy for reducing the risk of CD-related complications in patients with colonic disease location relative to ileal disease location.