Adequate vitamin D is associated with favorable disease outcome in children with inflammatory bowel disease receiving anti‐tumor necrosis factor alpha therapy

OBJECTIVES: Deficiency of serum 25-hydroxyvitamin D [25(OH)D] was associated with decreased short-term response to anti-tumor necrosis factor-alpha (TNF-α) agents in adults with inflammatory bowel disease (IBD). The aim of this study was to evaluate the association between serum 25(OH)D levels and the outcome of children with IBD undergoing anti-TNF-α therapy. METHODS: Children with IBD who were treated with anti-TNF-α agents and whose 25(OH)D levels had been measured at the initiation of therapy were included. Demographic, clinical, and laboratory data were collected retrospectively between 1/2012 and 1/2022. 25(OH)D levels above 30 ng/mL were considered sufficient. RESULTS: A total of 150 children with IBD were treated with anti-TNF-α agents, and 84 of them (58 Crohn's disease, 26 ulcerative colitis, median [interquartile range] age 15.2 [12.8-16.5] years) met the inclusion criteria. Sixty-five (77%) patients were 25(OH)D-deficient. Adequate 25(OH)D levels were associated with clinical response (hazard ratio [HR] = 4, 95% confidence interval [CI] 1.43-11.11, p = 0.008), and clinical remission (HR = 4.62, 95% CI 2.56-8.33, p < 0.001). While anti-TNF-α trough levels were comparable between 25(OH)d-deficient and non-deficient children, intensification of anti-TNF-α therapy was more prevalent among children with 25(OH)D deficiency (65% vs. 21%, p < 0.001). CONCLUSIONS: Adequate serum 25(OH)D is an independent predictor of a favorable outcome of pediatric IBD under anti-TNF-α therapy.