S1581 Evaluating the Risk of Inflammatory Bowel Disease Following Cholecystectomy: A Multicenter Propensity Score-Matched Cohort Study

Introduction: Previous studies suggest that post-cholecystectomy (CCY) patients have increased secondary bile acids, along with a shift in gut microbiota that alters the populations of both beneficial and pathogenic bacteria. Patients with Inflammatory Bowel Disease (IBD) exhibit higher levels of primary bile acids and lower concentrations of beneficial secondary bile acids. Secondary bile acids have been shown to have anti-inflammatory effects in colitis models, indicating protective roles against mucosal inflammation. However, the connection between cholecystectomy and IBD risk is still debated. We aimed to quantify the risk of incident Ulcerative colitis (UC) and Crohn’s disease (CD) after CCY. Methods: We queried the TriNetX database for adults (≥18 y) with cholelithiasis (2000-2025). Patients were classified as post-CCY or nonoperative controls. Propensity-score matching (1:1) balanced age, sex, ethnicity, and known IBD risk factors such as tobacco use, long-term antibiotics, and NSAID use, yielding 2 cohorts of 582,529 patients. Incident IBD was identified with International Classification of Diseases-10 codes ≥1 day after the index date. Risk ratios (RRs) and odds ratios (ORs) were calculated. Time-to-event was assessed using Kaplan–Meier curves and Cox models, which provided hazard ratios (HRs). Results: During a median follow-up of 6.2 years, UC occurred in 0.39% of post CCY patients vs 0.47% of controls, resulting in a risk ratio of 0.826 (95% CI 0.782, 0.874; P < 0.001) and a hazard ratio of 0.808 (0.764, 0.854; P < 0.001). CD developed in 0.24% post-CCY vs 0.29% of controls (RR 0.799 (0.744, 0.858), HR 0.781(0.728, 0.839); both P < 0.001). Risk reductions persisted across all UC and CD phenotypes, with no phenotype demonstrating an increased risk. Kaplan-Meier curves revealed higher IBD-free survival post-CCY (log-rank P < 0.001 for both UC and CD). Conclusion: Cholecystectomy was associated with an increased IBD risk, with a 17–20% relative risk reduction for both UC and CD, sustained across disease phenotypes. Prospective studies integrating bile acid profiling and microbiota sequencing are warranted to elucidate the underlying mechanisms, but the current literature suggests that anti-inflammatory alterations in secondary bile acids and the gut microbiota may play a role.