Tu1688 Serum Concentration of Estrogen Is Associated With Inflammatory Bowel Disease Activity

s45, 22-82 y) were studied.No significant demographic differences were noted between the groups.Serum 25(OH)D concentration was similar across all 3 groups (mean 70 nmol/L in patients with CD, 69 nmol/L in patients with UC and 67 nmol/L in healthy controls, p = NS).A significant inverse correlation between 25(OH)D and log calprotectin was noted in patients with CD (Pearson r = -0.38,p = 0.033), UC (r = -0.39,p = 0.039) and all patients with IBD (r = -0.39,p = 0.003) (Fig 1).No correlation with C-reactive protein was noted.34 of the 68 patients with IBD were concurrently taking vitamin D supplements; in these patients, a significant inverse correlation between 25(OH)D and log calprotectin was also noted (r = -0.50,p = 0.006).The inverse correlation was also noted amongst patients with only colonic CD or UC (r = -0.36,p = 0.031).No significant difference in sunlight exposure was noted between the groups.In a subgroup of 20 healthy controls, 20 patients with CD and 15 patients with UC, DBP was similar across the 3 groups, as were calculated free and bioavailable 25(OH)D.Free and bioavailable 25(OH)D significantly correlated with FC on univariate linear regression in the IBD group as a whole or with CD and UC alone, whereas DBP did not.Conclusions: Despite total, free and bioavailable 25(OH)D concentrations being similar to those in a healthy control population, they inversely correlate with the degree of intestinal inflammation.This association is not influenced by potential malabsorption or variations of sunlight exposure; and hence provides further evidence that vitamin D may play an immunomodulatory role in IBD.Studies are required at the intestinal level.