Early Arthritis Is Associated With Failure of Immunosuppressive Drugs and Severe Pediatric Crohn's Disease Evolution

Crohn's disease (CD) is a chronic relapsing inflammatory disease. To optimize therapeutic decision making, it is essential to identify parameters that allow early prediction of a severe disease course. The aim of this study was to assess the link between arthritis and medium-term therapeutic failure in pediatric CD.

We conducted a population-based cohort study with prospectively collected electronic data. To be included, patients must be younger than 17 years and have a confirmed CD diagnosed between 2005 and 2014. The primary outcome was the percentage of patients with at least 1 therapeutic failure of immunosuppressive drugs during the 2 years after the CD diagnosis, with a propensity score analysis.

We included 272 patients with CD. The median age was 12.1 years (interquartile [10.1-14.2]). Sixty-five patients (23.9%) developed arthritis, which predominantly occurred during the first year after CD diagnosis. We found a highly significant association between arthritis and therapeutic failure of immunosuppressive drugs after 2 years (OR = 6.9; 95% confidence interval [CI], 2.7-18.0; P < 0.0001; propensity score matching analysis). Arthritis was also significantly associated with introduction of biotherapy due to luminal disease 2 years after diagnosis (OR = 3.2, 95% CI, 1.8-6.0; P = 0.0001). Similar results were obtained after 4 years, and arthritis was significantly associated with a higher number of hospitalizations for luminal flare-up or complications after 4 years (OR = 2.2; 95% CI, 1.2-3.9; P = 0.007).

Arthritis was strongly associated with medium-term therapeutic failure of pediatric CD. Occurrence of arthritis early in the disease may justify closer follow-up visits or specific therapeutic management.