P1170Biologics are not associated with increased risk of Clostridioides difficile infection in Inflammatory Bowel Disease: a retrospective cohort study

Background Clostridioides difficile infection (CDI) is a common and serious complication in patients with inflammatory bowel disease (IBD). The risk associated with newer biologic therapies like Vedolizumab (VDZ) remains a subject of inquiry. This study aimed to identify risk factors for CDI in IBD patients, with a specific focus on VDZ exposure, and to develop a predictive model for CDI diagnosis. Methods We conducted a retrospective study of 178 IBD patients, comprising 68 CDI-positive and 110 CDI-negative cases. Univariate and multivariate analyses were performed to identify significant demographic, clinical, and therapeutic risk factors for CDI. A nomogram prediction model was developed and its performance was evaluated using the C-index, AUC-ROC analysis, and the Hosmer-Lemeshow goodness-of-fit test. Results The overall CDI prevalence was 38.2%, with no significant difference between ulcerative colitis (39.7%) and Crohn’s disease (33.3%) (p > 0.05). Key risk factors for CDI identified were age <45 years, hemoglobin <100 g/L, albumin <30 g/L, and immunosuppressant use within the last 3 months (p < 0.05 for all). Crucially, treatment with VDZ was not a significant risk factor (p > 0.05). The CDI rates were similar across treatment groups: 37.5% (VDZ), 24.1% (anti-TNF-α), and 42.2% (no biologics) (p > 0.05). The nomogram model, based on age, hemoglobin, and immunosuppressant use, demonstrated moderate predictive accuracy with a C-index of 0.738 and an AUC of 0.738 (95% CI: 0.653–0.822). The model showed good calibration (H-L test, p > 0.05). Conclusion Biologics therapy does not appear to increase the risk of CDI in IBD patients. The primary risk factors are younger age, anemia, hypoalbuminemia, and recent immunosuppressant use. The developed nomogram provides a clinically useful tool with moderate accuracy for stratifying CDI risk in this patient population, potentially aiding in targeted monitoring and prevention strategies. Conflict of interest: Dr. Wang, Kairuo: No conflict of interest Shi, Haitao: Sha, Suemi: No conflict of interest Liu, Xin: I have received research funding from Takeda (China).