Vitamin D deficiency in children with inflammatory bowel disease

Osteopenia and osteoporosis are commonly seen in inflammatory bowel disease (IBD). Vitamin D deficiency potentially contributes to diminished bone acquisition in childhood.

The objectives of this study were to assess vitamin D in a group of Australian children with IBD and to ascertain associations between vitamin D status and key clinical factors, for example disease location and severity.

Data were obtained retrospectively from the records of children with IBD who had at least one measurement of serum 25-hydroxyvitamin D (25(OH)D) over a two-year period. Demographic variables, disease activity, inflammatory markers, disease location, duration, and therapy were recorded. Moderate and severe deficiency were defined as 25(OH)D <51 nmol/l and <30 nmol/l, respectively. Insufficiency was defined as 25(OH)D between 51 and 75 nmol/l.

Overall, the mean 25(OH)D level in 78 children (104 measurements) was 71.2 (SD ± 26.5) nmol/l. Fifteen (19%) children were vitamin D deficient and 30 (38%) children were insufficient. Levels of 25(OH)D were not associated with disease location or use of immunosuppressive drugs. Children with vitamin D deficiency had greater corticosteroid exposure than those with normal status (P = 0.001). The mean 25(OH)D of 38 children treated with nutritional therapy at diagnosis was higher than for 17 children initially treated with corticosteroids (P = 0.04).

A high proportion of these Australian children with IBD were vitamin D deficient. This emphasizes the importance of monitoring vitamin D status, and treating deficiency, in the management of pediatric IBD. The possible benefit of nutritional therapy in protection against vitamin D deficiency requires further prospective study.