The ImproveCareNow Registry: Prediction of remission rates in paediatric Crohn's disease

Abstract Objectives Identifying predictors of poor outcomes (POPO) in paediatric Crohn's disease (CD) may guide therapy. We assessed predictors of 2‐year non‐remission (primary outcome) and time to first remission (TFR), corticosteroid‐free remission (TCSFR, ≥3 months corticosteroid (CS) withdrawal and sustained remission (TSR, ≥6 months) (secondary outcomes) in paediatric CD. Methods We retrospectively analysed prospectively collected data from 6959 paediatric CD patients (<18 years; 2007–2023) in the ImproveCareNow Registry. Remission was defined as a short Paediatric CD Activity Index <10. Logistic and Cox regression ( α = 0.05), using R 4.5.0 with multiple imputation, identified predictors for both outcomes (at 0, 1, 5, 6, 12, and 24 months). Results For the primary outcome, 53/794 patients (6.7%) failed to achieve remission during 2‐year follow‐up. Female sex (odds ratio [OR] = 3.12, 95% confidence interval [CI] 1.48–6.55) and need for ustekinumab after 1 year (OR = 14.70, 95% CI 4.37–49.46) predicted non‐remission. For the secondary outcomes ( n = 3290), mean TFR, TCSFR and TSR were 4.5, 16.4, and 8.2 months, respectively. Longer TFR was predicted by female sex (hazard ratio [HR] = 0.81, 95% CI 0.71–0.92) and the need for infliximab (IFX, HR = 1.15, 95% CI 1.00–1.32) at first visit. Longer TCSFR was associated with female sex (HR = 0.85, 95% CI 0.78–0.93), race (white HR = 0.83, 95% CI 0.74–0.93 and Asian HR = 1.42, 95% CI 1.05–1.92) and type of treatment at first visit (faster if IFX, slower if CS or immunomodulators). For TSR, predictors included age at diagnosis (HR = 1.06, 95% CI 1.02–1.11) and body mass index (BMI) (HR = 0.97, 95% CI 0.94–1.00). Conclusions Clinical parameters (female sex, younger age, and higher BMI) and therapeutic strategy (early/late use of biologicals) are POPO and associated with longer time to remission in paediatric CD.