Low Vitamin D Levels can Effect the Balance of Immun Mediators in Fibromyalgia Syndrome Objective

Objective: To investigate the relationship between vitamin D levels and inflammatory cytokine levels in patients with Fibromyalgia Syndrome (FMS). Materials and Methods: 29 women with FMS who were diagnosed according to American College of Rheumatology (ACR) 2010 fibromyalgia diagnostic criteria and 25 healthy women as the control group was included in the study. Serum levels of vitamin D, Vitamin D Receptor (VDR) and Vitamin D Binding Protein (VDBP), and inflammatory cytokines (IL-2, IL-4, IL-6, IL-12, IFN-γ) were analyzed using by ELISA method. Widespread body pain, fatigue, morning stiffness, cognitive symptoms, somatic symptoms, Fibromyalgia Impact Questionnaire (FIQ) scores were evaluated in patients with FMS. Results: Vitamin D, VDR, and VDBP levels were found to be higher in the healthy individuals compared to the patients with FMS (p<0.001, p<0.002, p<0.001, respectively). Correspondingly, pro-inflammatory (IL-2, IL-12, IFN-γ), anti-inflammatory (IL-4), and both pro and anti-inflammatory (IL-6) cytokine levels of the control group were higher than the patients with FMS (p<0.001, p<0.006, p<0.004, p<0.001, p<0.049, respectively). Conclusion: Low vitamin D levels in FMS may negatively affect the release of inflammatory cytokines and this functional relationship may be in the etiology of this chronic pain disorder