Evaluation of Serum Vitamin D Level and its Effect on the Severity of Disease in Patients with Inflammatory Bowel Disease

Background: Evolving evidence indicates the role of vitamin D deficiency in the progression of IBD and its impact on the severity of the disease, but it remains unclear whether vitamin D deficiency causes IBD or vice versa. Methods: This cross-sectional study was conducted to determine the serum levels of vitamin D and its effects on the severity of disease in patients with inflammatory bowel disease in the Imam Khomeini Hospital complex. A questionnaire containing demographic information, records on the use of supplements and medications, disease complications, and criteria for determining the severity of the disease based on the Mayo score and Crohn’s Disease Activity Index (CDAI) and 25 hydroxy vitamin D levels was completed and evaluated. Results: Of the 101 participants, 21 were with Crohn’s disease and 80 had ulcerative colitis. The mean age of Crohn’s patients was 33.80±9.5 years and ulcerative colitis was 38.43±10.2 years. Among patients with ulcerative colitis, 37 (46.8%) had a mayo score less than 3 and 42 (53.2%) were 3 and more. Mean vitamin D in the mayo score less than 3 was 32.14 and the mayo score 3 and more was 23.99. Of the Crohn’s patients, 12 (57.1%) were in the recovery phase and 9 (52.9%) were in a non-recovery phase. The mean of vitamin D in the recovery phase was 29.10 and in the others was 27.04 Conclusion: There is a significant relationship between the level of vitamin D supplementation, the final value of CDAI, and the identification of the patients with the Mayo score.