title: Effect of vitamin D3 supplementation on TNF-α serum level and disease activity index in Iranian IBD patients.
abstract: OBJECTIVE
  The aim of the study was to assess the effectiveness of vitamin D3 [1, 25(OH)2D3] treatment in IBD with regard to tumor necrosis factor-alpha (TNF-α) serum level and clinical disease activity index (CDAI).
  
  
  BACKGROUND
  Vitamin D has immune-regulatory functions in experimental inflammatory bowel disease (IBD) and vitamin D deficiency is common in IBD patients.
  
  
  METHODS
  This was a randomized clinical trial on 108 IBD patients with serum 25-OHD levels less than 30ng/ml, which divided into vitamin D and control groups. Vitamin D group received 50000 IU vitamin D3 for 12 weeks. Before and after the study, TNF-α and 25-OHD serum levels were measured by ELISA method. Data were analyzed using paired t-test, chi-square test and Spearman correlation coefficient. P-values ​​less than 0.05 were considered statistically significant.
  
  
  RESULTS
  Before the intervention no significant difference was found between baseline characteristics and TNF-α serum level of two groups. After intervention TNF-α serum level reduced but this reduction was not statistically significant (p= 0.07, 95% CI: -0.45 to 8.14). The mean serum 25-OHD level of vitamin D increased from 15.54 to 67.89, which was statistically significant (p= 0.00, 95% CI: -61.40 to -43.30). TNF-α level was also associated significantly with CDAI before (Spearman's rho: 0.3, p<0.0001) and after (Spearman's rho: 0.27, P=0.01) intervention.
  
  
  CONCLUSIONS
  Oral supplementation vitamin D3 significantly increased serum vitamin D levels and insignificantly reduced serum TNF-α level. More studies with larger samples would be beneficial to assess vitamin D3 supplementation efficient effect in IBD.
authors.affiliation: Gastroenterology and Liver Disease Research Center, Shahid Beheshti University of Medical Science, Tehran, Iran.
authors.forename: Tahereh
authors.initials: T
authors.lastname: Dadaei
authors.affiliation: Gastroenterology and Liver Disease Research Center, Shahid Beheshti University of Medical Science, Tehran, Iran.
authors.forename: Mohammad Hosein
authors.initials: MH
authors.lastname: Safapoor
authors.affiliation: Gastroenterology and Liver Disease Research Center, Shahid Beheshti University of Medical Science, Tehran, Iran.
authors.forename: Hamid
authors.initials: H
authors.lastname: Asadzadeh Aghdaei
authors.affiliation: Gastroenterology and Liver Disease Research Center, Shahid Beheshti University of Medical Science, Tehran, Iran.
authors.forename: Hedie
authors.initials: H
authors.lastname: Balaii
authors.affiliation: Gastroenterology and Liver Disease Research Center, Shahid Beheshti University of Medical Science, Tehran, Iran.
authors.forename: Mohammad Amin
authors.initials: MA
authors.lastname: Pourhoseingholi
authors.affiliation: Gastroenterology and Liver Disease Research Center, Shahid Beheshti University of Medical Science, Tehran, Iran.
authors.forename: Nosratollah
authors.initials: N
authors.lastname: Naderi
authors.affiliation: Gastroenterology and Liver Disease Research Center, Shahid Beheshti University of Medical Science, Tehran, Iran.
authors.forename: Homayoon
authors.initials: H
authors.lastname: Zojaji
authors.affiliation: Gastroenterology and Liver Disease Research Center, Shahid Beheshti University of Medical Science, Tehran, Iran.
authors.forename: Pedram
authors.initials: P
authors.lastname: Azimzadeh
authors.affiliation: Gastroenterology and Liver Disease Research Center, Shahid Beheshti University of Medical Science, Tehran, Iran.
authors.forename: Parvaneh
authors.initials: P
authors.lastname: Mohammadi
authors.affiliation: Gastroenterology and Liver Disease Research Center, Shahid Beheshti University of Medical Science, Tehran, Iran.
authors.forename: Mohammad Reza
authors.initials: MR
authors.lastname: Zali
keywords: Inflammatory bowel disease; TNF-α; Vitamin D