RESUMEN
BACKGROUND: Fibromyalgia is a syndrome characterized by chronic widespread pain accompanied by fatigue, disrupted sleep quality, cognitive impairments, subjective soft tissue swelling, and somatic symptoms. There are conflicting results in the literature regarding the prevalence of vitamin D deficiency in fibromyalgia patients and the reduction of symptoms after supplementation. AIMS: Our study aims to evaluate the effectiveness and reliability of vitamin D supplementation in patients diagnosed with fibromyalgia. METHODS: In our cross-sectional clinical study, 180 female patients aged 18 to 65 diagnosed with fibromyalgia according to the 2010 American College of Rheumatology Diagnostic Criteria were included. Oral vitamin D3 replacement of 50,000 IU was administered for 12 weeks. Patients' Fibromyalgia Impact Questionnaire (FIQ)and Visual Analogue Scale (VAS) scores were evaluated before and after the study. RESULTS: Significant differences were observed in the FIQ scores of the 180 fibromyalgia patients before and after vitamin D supplementation (p < 0.05). There was also a significant improvement in VAS scores (p < 0.01). A negative correlation between vitamin D and VAS as well as FIQ scores was found in the study. CONCLUSION: We determined that vitamin D deficiency is significantly more prevalent in patients diagnosed with fibromyalgia. Vitamin D supplementation was observed to have a positive effect on quality of life and reduction of pain.