POS0019 CENTRAL SENSITIZATION IN PATIENTS WITH RHEUMATOID ARTHRITIS: ASSOCIATION WITH DISEASE ACTIVITY

Abstract

BackgroundRheumatoid arthritis (RA) is the most common inflammatory arthropathy with a predominance of autoimmune mechanisms of pathogenesis and pain as the main clinical manifestation. Recent evidence has found showed that Central Sensitization (CS) may be a new mechanism for the formation of pain [1]. There is insufficient data on this phenomenon in patients with RA [2].ObjectivesTo determine the prevalence of the phenomenon of CS in patients with RA and evaluate its association with disease activity.MethodsThe study involved patients with RA according to the ACR / EULAR criteria (2010). RA activity was determined by DAS-28, SDAI, CDAI, and the functional ability of patients - by HAQ. Visual analog scoring (VAS) were used to evaluate the intensity of pain. The radiological stage of RA was determined according to the Kellgren-Lawrence classification. The presence of the CS phenomenon was established using the Central Sensitization Inventory (CSI) (Mayer, T. G. et al., 2012). MS Excel and SPSS22 (© SPSS Inc.) software packages were used for statistical processing of results.Results110 patients (84% of women) with RA were included. The participants’ mean age was (M±SD) 53.5 ± 12.2 years, with a disease duration 8.5 ± 8.1 years. Among the examined, radiological stage I was detected in 16 (15%) patients, II - in 59 (53%), III - in 23 (21%), IV - in 12 (11%). According to the DAS28-ESR index, 56 (51%) patients had high activity (DAS 28-ESR: > 5.1) and 54 (49%) patients had moderate activity (3.2 <DAS28-ESR ≤5.1). Mean values of SDAI and CDAI also showed high disease activity: 36.5 ± 10.2 and 33.3 ± 9.8, respectively. The average value of HAQ was 1.4 ± 0.7.CS (CSI>40) was revealed in 40 (36%) patients. Correlation analysis showed that CSI was significantly correlated with disease activity, VAS pain and HAQ: DAS28-ESR (r = 0.477; p <0.01), SDAI (r = 0.559; p <0.01), CDAI (r = 0.544; p <0.01), VAS (r = 0.575; p <0.01), HAQ (r = 0.694; p <0.01). It was found that the group of patients with CS had higher rates of disease-specific values compared to patients without CS. Significance of differences between groups was at the level of p <0.01 (Table 1).Table 1.Characteristics of the RA patients with and without CS on the indices disease activity, VAS pain and HAQ.CSI<40(n=70)CSI>40(n=40)РCDAI29,7±7,838,9±9,7<0,01SDAI32,9±8,642,3±9,6<0,01HAQ1,1±0,61,9±0,6<0,01DAS28-ESR4,9±0,95,7±0,8<0,01VAS6,3±1,37,8±1,2<0,01Notes: SDAI – The Simple Disease Activity Index, CDAI - The Clinical Disease Activity Index, DAS-28 - The Disease Activity Score-28, HAQ-DI - Health Assessment Questionnaire,VAS - Visual Analog Scoring, p – the significance of differences between groups.ConclusionCentral sensitization is common in RA patients. The phenomenon of central sensitization is associated with higher disease activity, loss of functional ability and severity of pain.