Risk factors for immune checkpoint inhibitor colitis: a retrospective multi-center cohort study using electronic health records

Fourteen significant predictors of CIC were identified. The strongest predictors were concurrent use of antibiotics (HR 2.72, 95% CI: 2.41-3.07) and non-steroid anti-inflammatory drugs (1.50, 1.16-1.94). Notable GI risk factors included gastroesophageal reflux disorder (1.31, 1.14-1.50), other GI disorders (1.32, 1.16-1.50), and disorders of the gallbladder, biliary tract, and pancreas (1.33, 1.15-1.57). High BMI before ICI administration increased risk (per unit 1.07, 1.04-1.09), while higher BMI after ICI administration decreased risk (per unit 0.93, 0.90-0.95). Melanoma, anxiety, and depression also increased risk. GI oncologists should consider ICI colitis in patients with comorbid GI disorders or those using antibiotics or NSAIDs. A routine checkup for colitis could be beneficial for those patients. Future studies are needed to explore the underlying mechanisms and quantify clinical impact of increased checkups for colitis.