Use of Vitamin D With Anti-Tumor Necrosis Factor Therapy for Crohn's Disease

Vitamin D (VD) has an important role in regulating gut mucosal immunity, and seems to be inversely linked to disease activity and more frequent relapses in inflammatory bowel disease. In this study, we evaluated patients with Crohn's disease (CD) treated with anti-tumor necrosis factor (TNF) in association with VD.

A double-blind, randomized, prospective study was conducted. Thirty patients with a history of moderate to severe CD, in use of anti-TNF, of both sexes, 18 to 70 years, with the dosage of VD < 75 nmol/L (30 ng/mL) were randomized and divided into three groups: group 1 (G1): 10 patients received 2,000 IU VD, per os (PO)/week for 8 weeks; group 2 (G2): 10 patients received 10,000 IU VD, PO/week for 8 weeks; group 3 (G3): 10 patients received 50,000 IU VD, PO/week for 8 weeks. Before and at the end of 8 weeks patients were submitted to VD, fecal calprotectin (FC) and C-reactive protein (CRP) dosage. Follow-up period was 52 weeks, and they are checked for disease activity recurrence (Crohn's disease activity index (CDAI) > 150, FC > 300 and computerized tomography (CT) scan), FC, CRP, and VD levels.

Increased VD levels were observed in all groups (P < 0.0001). CRP did not change. There was a significant decrease of FC in G3 (1,014 ± 850 vs. 483 ± 564; P = 0.04), no significant decrease in G2 (76,767 ± 751 vs. 535 ± 823; P = 0.2) and increase in G1 (1,101 ± 744 vs. 1,357 ± 819; P = 0.4). During the 52-week follow-up period, it was showed that recurrent disease activity (CDAI > 150, FC > 200 and CT scan) was predominant in patients with VD < 30 group, and the remission rate was predominant in patients with VD > 30 group (P = 0.0001). A statistically significant difference in VD levels was noted in CD patients after 52 weeks that presented flare or disease remission (P = 0.001).

Use of VD associated with anti-TNF treatment may improve clinical response in CD. VD levels greater than 30 ng/mL have better rates of remission.