The Vitamin D Status in Inflammatory Bowel Disease

CONTEXT There is no consensus on the vitamin D status of children and adolescents with inflammatory bowel disease (IBD). AIM To determine the vitamin D status of patients with IBD by comparing their serum 25(OH)D concentration to that of healthy controls. HYPOTHESIS Serum 25(OH)D concentration will be lower in patients with IBD compared to controls. SUBJECTS AND METHODS A case-controlled retrospective study of subjects with IBD (n = 58) of 2-20 years (male n = 31, age 16.38±2.21 years; female n = 27, age 16.56±2.08 years) and healthy controls (n = 116; male n = 49, age 13.90±4.59 years; female n = 67, age 15.04±4.12 years). Study subject inclusion criteria: diagnosis of Crohn's disease (CD) or ulcerative colitis (UC). Vitamin D deficiency was defined as 25(OH)D of (<20 ng/mL) (<50 nmol/L), overweight as BMI of ≥85th but <95th percentile, and obesity as BMI ≥95th percentile. Data were expressed as mean ± SD. RESULTS Patients with CD, UC, and their controls had mean serum 25(OH)D concentrations of 61.69±24.43 nmol/L, 53.26±25.51, and 65.32±27.97 respectively (ANOVA, p = 0.196). The overweight/obese controls had significantly lower 25(OH)D concentration compared to the normal-weight controls (p = 0.031); whereas 25(OH)D concentration was similar between the normal-weight and overweight/obese IBD patients (p = 0.883). There was no difference in 25(OH)D between patients with UC and CD, or between subjects with active IBD and controls. However, IBD subjects with elevated ESR had significantly lower 25(OH)D than IBD subjects with normal ESR (p = 0.025), as well as controls (65.3±28.0 nmol/L vs. 49.5±25.23, p = 0.045). CONCLUSION There is no difference in mean serum 25(OH)D concentration between children and adolescents with IBD and controls. However, IBD subjects with elevated ESR have significantly lower 25(OH)D than controls. Therefore, IBD subjects with elevated ESR should be monitored for vitamin D deficiency.