P471 Predictors of bowel damage in long term progression of Crohn’s disease

Abstract

Abstract Background Crohn’s disease is a chronic inflammatory bowel disorder that progresses to bowel damage over time. An image-based index, the Lémann Index, has been developed to measure the cumulative bowel damage. AIMS To characterize the long-term progression of bowel damage in Crohn’s disease based on changes in the Lémann Index and to determine risk factors for long term progression. Methods This was a single-center longitudinal cohort study. Patients who had participated in prospective studies on the accuracy of magnetic resonance imaging using endoscopy as gold standard and had a follow-up of at least 5 years were reevaluated after 5–12 years. Results Seventy-two patients were included. Lémann Index increased in 38 patients (52.8%), remained unchanged in 9 patients (12.5%) and decreased in 25 patients (34.7%). Small bowel score and surgery subscale significantly increased (p=0.002 and p=0.0001), whereas fistulizing subscale significantly decreased (p=0.001). Baseline parameters associated with bowel damage progression were ileum location (p=0.026), phenotype (stricturing, fistulizing or both with p=0.007, p=0.006 and p=0.035), disease duration >10 years (p=0.019) and baseline Lémann Index stricturing score (p=0.049). No correlation was observed between bowel damage progression and baseline clinical activity, biological markers or endoscopic lesions. Need of surgery during follow-up was a major determinant of bowel damage progression (p=0.0001). Baseline stricturing Lémann Index score was associated with the risk of future surgery (p=0.02). Conclusion Bowel damage, assessed by the Lémann Index, progresses in half of the patients with Crohn’s disease over a period of 5–12 years. The main determinants of bowel damage progression are ileum location, stricturing/fistulizing phenotype and disease duration.