Stoma formation and associated risk factors in patients with Crohn′s disease in an Austrian tertiary referral hospital: A retrospective explorative study of long-term follow-up

Background The cumulative probability of patients with Crohn’s disease (CD) requiring a stoma at a tertiary center is unknown. We sought to evaluate the time to stoma formation after diagnosis as well as risk factors for stoma formation in CD patients. Methods This is a retrospective, longitudinal cohort study on consecutive patients with CD at an Austrian tertiary referral university center. In brief, patients with CD were identified and disease-specific data were captured prior to June 2023. The probability of stoma-free survival by subgroups of various potential risk factors was assessed by means of Kaplan-Meier estimates (Log-rank test). Results Of 1267 CD patients, 142 (11.2%) underwent a stoma formation (80 ileostomies, 62 colostomies), of which 51 (35.9%) were permanent stomas. The probability of stoma-free survival at 10 and 20 years after diagnosis was 92% and 86%, respectively. Ileocolonic and colonic location, penetrating behavior, and perianal disease were associated with a higher risk for stoma formation (each p < 0.001). If these risk factors coincided, the probability of stoma-free survival at 10 and 20 years after diagnosis was only 76.4% and 67.2%, respectively. Patients diagnosed from 2000 onwards had a trend for a lower stoma risk than patients diagnosed earlier (p = 0.084). Conclusions The coincidence of colonic or ileocolonic involvement, penetrating behaviour and perianal fistulas significantly reduced the probability of stoma-free survival to 68% 20 years after diagnosis. Identification of these risk factors for stoma formation may help identify patients at risk and thus raise awareness for this group.