AB1350 Is the radiographic damage a risk factor for neuropathic 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> Features suggestive of neuropathic pain (NP) have been described in Rheumatoid Arthritis (RA) patients. The structural damage assessed on radiographs is a direct consequence and reflection of cumulative of disease activity and its association with NP has not been studied in RA. <h3>Objectives</h3> To determine whether existence and intensity of NP is associated with radiographic damage in RA patients. <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. Two questionnaires were applied to assess NP: the Leeds Assessment of Neuropathic Symptoms (LANSS) and the painDETECT (PDQ). Wrist, hands and feet radiographic studies from the previous 12 months before were classified according to the modified van der Heijde Sharp's method by one trained reader, blinded for patient clinical variables and treatment allocation. Correlation studies (spearman coefficient analysis) and univariate and multivariate logistic regression were performed. Significance level was set as &lt;0.05. <h3>Results</h3> Ninety one RA patients were included. Seventy (77%) were women, with a mean 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 conventional synthetic Disease-Modifying Antirheumatic Drugs (DMARDs) and 41% with a biological DMARD (bDMARDs). The mean DAS28 4V CRP was 3.15±0.77 and the mean HAQ score was 1.04±0.6. The median joint erosion score (JE) was 28<sup>3–143</sup> and the median joint space narrowing (JN) was 46.<sup>10–133</sup> Forty-two (46%) patients had LANSS NP (≥12), 29% had a possible/likely NP in the PDQ (&gt;12), and 13% had likely NP in the PDQ (&gt;18). JN and global score (GS) had a negative weak correlation with LANSS (r=−0.21 and r=−0.25, respectively, p&lt;0.05) and JN correlated with PDQ (r=−0.23, p=0.03). No significant correlations were observed with JE. Disease duration significantly correlated with all the radiographic scores (r=0.48 for GS, r=0.43 for JN, r=0.44 for JE, p&lt;0.05) and negatively correlated with LANSS (r=−0.28, p=0.01). Lower median GS values were observed in LANSS positive group (62 vs 79, p=0.01). Patients under bDMARDs had significant higher median GS (80 vs 61, p=0.03) but also higher disease duration (14 vs 10, p=0.01). No statistically significant differences were observed for other variables. Disease duration was a negative predictor of LANSS NP (OR: 0.98, p=0.03). JN was inversely associated with LANSS NP (OR: 0.978, p=0.02) and remained significant after adjustments for bDMARDs treatment, but not for disease duration. JN was a also a negative predictor of PDQ likely NP and remained significant after adjustment for bDMARDs (OR: 0.979, p=0.03), but not for disease duration. <h3>Conclusions</h3> In this cohort, JN score had a weak negative association with NP. Higher structural damage and disease duration do not seem to increase the risk of non-nociceptive RA pain. Further studies are needed to confirm these results. <h3>References</h3> [1] Koop SM, et al. Arthritis Res Ther. 2015; 17:237 [2] van der Heijde D. J Rheumatol1999;26:743–5. <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