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.