AB0311 Determinants of non-nociceptive pain in rheumatoid arthritis
Authors: T.M. Rocha, S. Pimenta, M. Bernardes, A. Bernardo, M. Barbosa, R. Lucas, L. Costa
Journal: Annals of the Rheumatic Diseases (2018)

<h3>Background</h3> A neuropathic component (NP) of Rheumatoid Arthritis (RA) pain was described in nearly a third of the patients. Radiographic damage is a reflection of cumulative disease activity and other pathophysiological processes. Some clinical predictors of RA NP were recently identified by our group, but association and adjustment for radiographic damage were not studied. <h3>Objectives</h3> To estimate the clinical predictors of NP in RA patients adjusting for their radiographic damage. <h3>Methods</h3> Cross-sectional study was performed with RA patients followed at our Rheumatology department. Patients with diagnosed neuropathy or non-RA risk factors for NP were excluded. Selected patients were evaluated in a medical visit. Demographic and clinical data were collected and two questionnaires were applied to assess NP: the Leeds Assessment of Neuropathic Symptoms (LANSS) and the painDETECT (PDQ). Wrists, hands and feet radiographic studies from the previous 12 months were classified according to the modified van der Heijde Sharp's method by one trained reader, blinded for patient clinical variables and treatment allocation. Univariate and multivariate logistic regression were performed adjusting for global radiographic score (GS). Significance level was set as &lt;0.05. <h3>Results</h3> Ninety one RA patients were included. Seventy (77%) were women, with a mean (SD) age of 55.6 (10.8) years and median disease duration of 12 years;<sup>2–41</sup> 84% patients were seropositive for Rheumatoid Factor and/or ACPA; 85 (93%) were treated with DMARDs and 41% with a biological DMARD (bDMARDs). The mean (SD) DAS28 4V CRP was 3.15 (0.77). The median joint erosion score was 28 (range: 3–143) and the median joint space narrowing (JN) was 46 (range: 10–133). Forty-two (46%) patients had LANSS NP (≥12) and 29% had a possible/likely NP in the PDQ (&gt;12). JN was a significant negative predictor of LANSS NP (OR: 0.98, p=0.02). After adjusting for GS, gender was not associated with NP. Pain VAS, patient global activity and the tender joint count were positive predictors of NP by both tests. Swollen joint count, ESR or CRP levels were not significantly associated with NP. DAS28 CRP was a significant positive predictor of NP by both tests (OR 1.89 for LANSS and OR: 2.06 for PDQ, p&lt;0.05); as well as the HAQ score (OR: 2.68 and OR: 4.85, respectively, p&lt;0.05). Positivity for ACPA was a negative predictor of LANSS NP (OR: 0.31, p=0.048), as previously described. Current methotrexate treatment had lower odds of LANSS NP (OR: 0.35, p=0.04) but did not remained significant after adjustment for DAS28 CRP. Previous/current Hydroxychloroquine (HCQ) treatment was once more a negative predictor for PDQ NP (OR: 0.11, p=0.04) and remained significant after adjustment for DAS28 CRP. Previous/current leflunomide (LFN) was newly a positive predictor of NP in both tests (OR: 3.41 for LANSS and OR: 2.95 for PDQ, p&lt;0.05), persisting after disease activity adjustment for LANSS NP. No other associations were found. <h3>Conclusions</h3> Consistently with our previous data, this study supports an association between NP and disease activity/functional scores but not with objective inflammatory measures. Possible increased risk of NP in LFN treated patients was newly pointed and protective role of ACPA positivity and HCQ was reinforced. <h3>References</h3> [1] Christensen AW, et al. Scand J Rheumatol2016;1–9. [2] Martins-Rocha T, et al. Ann Rheum Dis, 2017;76(suppl 2):1177. <h3>Disclosure of Interest</h3> T. Rocha Grant/research support from: Portuguese Society of Rheumatology/Alfa Wassermann on May 2015, S. Pimenta: None declared, M. Bernardes: None declared, A. Bernardo: None declared, M. Barbosa: None declared, R. Lucas: None declared, L. Costa: None declared