Comparison of the effects of vitamin D levels on quality of life in patients with fibromyalgia syndrome and rheumatoid arthritis

Objectives: Fibromyalgia syndrome (FMS) is a chronic non-inflammatory disease that affects the quality of life to a great extent and is accompanied by diffuse muscle and bone pain, waking tired in the morning, sleep problems and mood disorders. Rheumatoid arthritis (RA) is a chronic inflammatory disease that can present with symmetrical involvement of small joints, morning stiffness, joint deformity and systemic findings. Vitamin D is a hormone with various effects on the musculoskeletal system, central nervous system and immune system. The aim of this study was to compare the effects of vitamin D levels on pain, quality of life, anxiety and depression in patients with fibromyalgia syndrome and rheumatoid arthritis. Materials and Methods: Our study groups consisted of 30 women aged between 18-65 years who were diagnosed with FMS and RA, whose 25 hydroxyvitamin D [25(OH)D] levels were detected below 30ng / dl when tested for any reason. The patients were selected from the patients who applied to the Physical Medicine and Rehabilitation outpatient clinic of Ankara City Hospital between 1 March 2019 and 1 August 2019. FMS was diagnosed according to the 2016 American Collage of Rheumatology (ACR) diagnostic criteria and RA was diagnosed according to the 2010 ACR diagnostic criteria. Patients were evaluated with Visual Analogue Scale (VAS) at rest and with movement scores for pain; for quality of life, with Short Form-36 (SF-36) scale; for anxiety and depression, with Beck Depression Inventory and Hospital Anxiety and Depression Scale (HADS) were used. Results: There was no significant difference between age, body mass index (BMI), symptom duration and 25(OH)D levels of the FMS and RA patients. Pain scores (VAS with movement, VAS at rest, SF-36 pain sub-parameter) of FMS patients who participated in the study were significantly higher than RA patients. The effect of 25(OH) D levels on pain scores was significantly higher in FMS patients than in RA patients. There was no significant difference in 25(OH) D levels between the two diseases in terms of quality of life, anxiety and depression scores. Conclusions: While vitamin D deficiency and insufficiency were found to affect pain scores more in FMS patients than RA patients, vitamin D had similar effects on quality of life, anxiety and depression in both diseases.