Evolution of Growth following Anti-Tumor Necrosis Factor-α Therapy in Paediatric Crohn’s Disease: Data from the Swiss IBD Cohort Study

Introduction: Up to 85% of pediatric patients affected by Crohn’s disease experience growth failure. This study aims to elucidate the effects of anti-tumor necrosis factor (TNF) biologics on patient growth. Methods: This retrospective analysis examined height, height velocity and weight in pediatric patients with Crohn’s disease from the Swiss Inflammatory Bowel Disease Cohort Study between 2007 and 2020 (n = 97). Z-scores were determined according to age and gender of a healthy pediatric population. Growth of patients treated with anti-TNF biologics and immunomodulators was analyzed by linear regression over 5 years and compared within each subgroup by paired Student t tests 1 year (T1), 2 years (T2), and 5 years (T5) after treatment initiation. Results: Mean height and weight z-scores at diagnosis were −0.3 ± 1.3 and −1.0 ± 1.6, respectively (age at diagnosis 11.1 ± 2.7 years, 52.0% male). Initial treatment was led by azathioprine (58.3%) and infliximab (19.8%). Patients treated with biologics exhibited significant height increase at T1 (p = 0.022), with an overall flat height evolution (y = 0.00x − 0.31), whereas significant weight increase was maintained at T5 (p = 0.0005, y = 0.13x − 0.50). Patients on immunomodulators showed a height increase (y = 0.15x − 0.20) and a significant weight increase at T2 (p = 0.0047, y = 0.10x − 0.41). Height velocity z-scores showed a significant increase across both genders. Factors contributing to a decreased height z-score included male sex, age 10 and below at diagnosis, a concomitant corticosteroid treatment and a top-down treatment strategy. Conclusion: Our findings indicate that anti-TNF biologics are associated with significant short-term height and long-term weight gains in pediatric patients with Crohn’s disease, similar to those observed with immunomodulators.