The Effects of Vitamin D Supplementation on Withdrawal Symptoms and the Expression of Inflammatory Cytokines and Insulin in Patients Under Methadone Maintenance Treatment: A Randomized, Double-Blind, Placebo-Controlled Trial

Background: Hypovitaminosis D may be related to some metabolic vulnerable, including metabolic disorders associated with inflammatory cytokines and insulin resistance in subjects undergoing methadone maintenance treatment (MMT). Objectives: This study aimed to determine the impact of vitamin D intake on withdrawal symptoms and genetic response related to inflammatory cytokines and insulin in patients treated with MMT. Methods: This investigation was performed on 40 subjects underMMTto consume either 50,000 IU vitaminDsupplements (n = 20) or placebo (n = 20) every 2 weeks for 12 weeks, between April and June 2017 in Kashan, Iran. The clinical opiate withdrawal symptoms (COWS) were evaluated to examine withdrawal scale and gene expression at baseline and after the a 3-month intervention. Statistical analysis of the data was performed using SPSS 18 with Fisher’s exact test, t-test, chi-square, and ANCOVA. Also, P values < 0.05 were considered statistically significant. Results: The results of our study showed that compared with the placebo, taking vitamin D downregulated interleukin-1 (IL-1) expression (P = 0.01) in peripheral blood mononuclear cells (PBMCs) of patients under MMT. In addition, consuming vitamin D increased peroxisome proliferator-activated receptor gamma (PPAR- ) expression (P = 0.01). Administration of vitamin D did not change COWS and IL-8 and tumor necrosis factor-alpha (TNF-) expression. Conclusions: According to the results of the present study, vitaminDcan be recommended as an adjunct toMMTwhichmayelevate the quality of life and decrease methadone side effects.