Background Fibromyalgia (FM) is well described as a concomitant syndrome that can frequently accompany connective tissue diseases, especially rheumatoid arthritis (RA). In this epoch of modern biologic therapy and RA tight control effort it is essential to count various factors that can impact RA activity or modulate activity assessment.
Objectives To compare proportional representation of FM in RA patients cohort according to increasing arthritis activity assessed by composite indices in a regional, monocentric, cross-sectional study.
Methods Examination of 120 consecutive patients (pts) with RA was performed in the terciary outpatient rheumatology department. Diagnosis of concomitant FM was established according to ACR criteria (1990). Standard Manual Tender Point Survey was used for the examination of FM tender points. The following data were recorded: demographic data, tender point count (TPC), Fibromyalgia Impact Questionnarie (FIQ) score and RA activity composite indices (DAS-28, CDAI, SDAI). Short Form 36 items (SF-36) and Health Assessment Questionnaire (HAQ) were used for evaluation of quality of life (QOL) and functional disability, respectively. Statistical analysis was based on Student's t-test or Fisher exact test (statistical significance level 0.05).
Results Concomitant FM was diagnosed in 25 (20.8%) pts with RA, 4 men and 21 women. Comparing RA without FM (RAF-) and with FM (RAF+), there were no significant differencies in sociodemographic characteristics, laboratory inflammatory markers, RF and ACPA seropositivity. RAF+ pts in comparison to RAF- pts reached significantly higher scores of RA activity (DAS-28 5.35±1.1 vs. 3.67±1.4, p<0.0001) and disability level (HAQ 1.83±0.64 vs. 0.87±0.76, p<0.0001). Analysing RA subgroups on the basis of rising disease activity we found increasing proportion of RAF+ pts in the subgroup with higher activity (DAS-28 <3.1 – 2.7% RAF+ pts; DAS-28 3.2-5.1 – 13.5%; DAS-28 >5.1 – 54.8%, p<0.0001). Similar results were found using other composite indices CDAI and SDAI.
Conclusions Concomitant fibromyalgia appears frequently in RA pts and has significant impact on the disease activity assessment and disability level because of altered pain perception. Patients with high disease activity measured by widely used composite indices are usually indicated for more intensive immunosuppressive or biologic therapy. But in this case it is necessary to realize this group contains higher portion of FM pts resulting in risk of wrong therapy reinforcement.
Disclosure of Interest : None declared