Comparison of inflammatory bowel disease relapse after top-down or step-up therapy: a population-based cohort study

The therapeutic effect of top-down therapy for inflammatory bowel disease (IBD) has not been fully evaluated in real-world clinical settings. We compared the effectiveness of top-down and step-up therapies for IBD.

We retrospectively evaluated patients who were admitted with IBD (Crohn's disease [CD] or ulcerative colitis [UC]) between 2012 and 2019 using the nationwide Japan Diagnosis Procedure Combination database. Patients who received immunomodulators or biologic agents at the start of observation were assigned to the top-down group and those who did not were enrolled in the step-up group. Relapse was the primary outcome, a composite outcome defined as surgery, new steroid or immunomodulator use, hospitalization, a new biologic agent, or switching biologic agents.

We analyzed 6715 patients (CD, N = 3643; UC, N = 3072). Relapse occurred in 1982 CD cases (54.4%). The cumulative CD relapse incidence was 32.9% at 1 year and 61.3% at 5 years in the top-down group and 30.7% at 1 year and 58.6% at 5 years in the step-up group. Relapse occurred in 2032 UC cases (47.8%). The cumulative relapse incidence was 33.5% at 1 year and 50.0% at 5 years in the top-down group and 35.2% at 1 year and 51.6% at 5 years in the step-up group. No clinical factors associated with relapse were identified in patients with CD or UC.

Compared with step-up therapy, top-down therapy was not associated with a decreased relapse risk in a real-world population of patients with CD or UC.