Independent risk factors for diversion colitis: a retrospective case-control study.

Objective: The aim of this study was to investigate independent risk factors for diversion colitis induced by the surgical interruption of fecal flow in the non-functional colon.

Methods: We performed a retrospective study with 163 patients who underwent low anterior resections and created prophylactic ileostomies for rectal cancer between January 2014 and June 2023 at the Department of General Surgery, Air Force Medical University Tangdu Hospital. Colonoscopy results of the non-functional region of the distal colon and clinical variables were collected, including age, sex, body mass index, pathological tumor node metastasis staging, ileostomy method, diversion time, receiving radiotherapy or chemotherapy or not, suffering from preoperative inflammatory bowel disease or postoperative anastomotic leakage or not. Diagnosis of diversion colitis based on the results of the patients' colonoscopy results. Univariate analysis and multivariate analysis of diversion colitis-related risk factors were performed subsequently.

Results: The morbidity of diversion colitis is 53.4% (87/163) in our study. Multivariate analysis showed that risk factors for diversion colitis included single-lumen prophylactic ileostomy (63.2 vs. 30.3%, OR 4.481, 95%CI 1.897-10.584, p<0.001), diversion time ≥90 days (79.3 vs. 40.8%, OR 4.474, 95%CI 1.849-10.826, p<0.001), inflammatory bowel disease (17.2 vs. 3.9%, OR 7.491, 95%CI 1.839-30.507, p=0.005), radiotherapy (58.6 vs. 42.1%, OR 0.515, 95%CI 0.196-1.352, p=0.178).

Conclusion: These findings suggest that single-lumen prophylactic ileostomy, diversion time, and inflammatory bowel disease are independent risk factors for diversion colitis.