LAUSR

BACKGROUND Evaluation of mucosal healing with colonoscopy is recommended for inflammatory bowel disease (IBD) management; however, little is known about real-world use of treat-to-target monitoring following IBD treatment initiation. We aimed to estimate the proportion of U.S. commercially insured IBD patients who receive colonoscopy in the 3 to 15 months after initiating treatment. METHODS We identified IBD patients, 18 to 64 years of age, in the IBM MarketScan Commercial Claims and Encounters database as those with ≥3 IBD diagnoses prior to initiation of biologic, small molecule, or immunomodulatory treatment. We excluded patients with prior colectomy and with rheumatologic and other indications for these therapies. Colonoscopies were identified using International Classification of Diseases-Ninth Revision, International Classification of Diseases-Tenth Revision, and Current Procedural Terminology procedure codes. We used Kaplan-Meier methods to estimate the proportion of newly treated IBD patients who received colonoscopy in the 3 to 6 months, 3 to 12 months, and 3 to 15 months following treatment initiation, and stratified trends by year, patient age and sex, and region. RESULTS From 2013 to 2019, we identified 39 734 initiators of IBD medications (51.9% female, mean age 39.4 years). We observed similar colonoscopy incidence among ulcerative colitis patients (3-6 months: 14.2% [95% confidence interval (CI), 13.6%-14.8%]; 3-12 months: 37.7% [95% CI, 36.8%-38.6%]; 3-15 months: 46.1% [95% CI, 45.2%-47.1%]) and Crohn's disease patients (3-6 months: 11.2% [95% CI, 10.8%-11.6%]; 3-12 months: 32.2% [95% CI, 31.5%-32.9%]; 3-15 months: CD: 40.1% [95% CI, 39.3%-40.8%]). Overall colonoscopy use was slightly higher among women, patients in the Northeast, and those initiating newer biologic therapies. CONCLUSIONS Fewer than half of newly treated IBD patients underwent colonoscopy within 3 to 15 months of initiating new treatment, suggesting low uptake of treat-to-target endoscopic disease monitoring in real-world practice.