Vitamin D Status in Paediatric Inflammatory Bowel Disease: a Cross-sectional Study

Objectives and study: Suboptimal circulating levels of vitamin D are common in IBD and appear to be associated with an increased risk of flares, hospitalizations, an inadequate response to tumour necrosis factor (TNF) inhibitors.

Methods: This is a cross-sectional study including paediatric IBD patients. Levels of vitamin were correlated with severity of the disease, specific disease activity index and activity of the disease. Levels <20 ng/mL were regarded as vitamin D deficiency, 20-30ng/mL as insuficient and >30ng/mL as optimal levels. Patients were divided in three treatment groups depending on their therapy (mesalazine /immunosuppressive agents and anti-TNF group).

Results: Thirty-one patients were analyzed including seven with Crohn’s disease (CD) and 24 with ulcerative colitis (UC);mean age at inclusion was 12,98 ±4 years. Mean level of vitamin D was 26,69±2,7ng/mL. Twenty-four patients (77,4%) from which four (57,1%) with CD and 20 (83,3%) with UC had low/insufficient levels of vitamin D (p=0,302), with no significant differences in the serum level between the two diseases (25,07±3ng/mL for UC vs. 32,22±5,7ng/mL for CD, p=0,302). Higher age at diagnosis was correlated with lower levels of vitamin D (r=-0,499, p=0,004). No correlation between specific disease activity indexes at diagnosis and at inclusion time were observed neither for the entire group (p=0,08 respectively p=0,174) nor for the Crohn’s disease subgroup (p=0,427 respectively p=0,459) and the UC subgroup (p=0,222 respectively p=0,289). Patients in remission had significantly higher levels of vitamin D than the ones exhibiting a flare of activity (30,52±4 ng/mL vs. 20,66±2 ng/mL, p=0,04). Vitamin D level was not significantly different between the three treatment groups (p ANOVA = 0,247).

Conclusion: Vitamin D deficiency common in patients with IBD. Higher age at diagnosis and flares of activity are associated with significantly lower vitamin D levels and may therefore require close monitoring for its deficiency.