Frequency and Characteristic of Concomitant Fibromyalgia in Patients with Rheumatoid Arthritis
Abstract Fibromyalgia (FM) is a confounding factor for diagnosing and assessing rheumatic disease activity. This study sought to assess the extent of this syndrome in rheumatoid arthritis (RA) patients at our rheumatology department. The RA patients were divided into 2 groups (RA with FM and RA without FM) according to the score of the FiRST questionnaire and modified 2016 criteria for FM. We compared the clinical data and disease activities of RA patients with and without FM. As a result, RA patients with FM showed higher levels of CRP, ESR, DAS28-ESR compared with RA patients without FM in both FiRST questionnaires and questionnaires developed to diagnose FM(2016 criteria).Furthermore, RA patients with FM showed higher levels of IgA compared to without FM. For the blood cells count, RA patients with FM showed higher levels of white blood cells, platelets and lower levels of hemoglobin compared with RA patients without FM. Only by FiRST Questionnaires, RA patients with FM showed higher levels of RF compared to without FM. However, all groups showed a similar pattern in anti-CCP and IgG, IgM. RA patients with FM showed lower levels of vitamin D (VD) and higher levels of interleukin (IL)-6 compared with RA patients without FM.In conclusion,FM is a common feature in RA, more associated with high values of disease activity such as ESR, CRP and DAS28-ESR.