FRI0042 DISCREPANCIES BETWEEN RAPID3 AND DAS28 IN RHEUMATOID ARTHRITIS PATIENTS IN REMISSION OR LOW DISEASE ACTIVITY RECEIVING TNF INHIBITORS: WHAT IS THE ROLE OF THE INFLAMMATION BIOMARKERS?

Abstract

Background:Patients and Rheumatologist often differ in their perception of RA disease activity. Remission or low disease activity should be the treatment target in RA, patients should be included in treatment decisions.Objectives:To identify factors influencing patient’s self-reported disease activity by RAPID3 test.Methods:47 RA patients in remission or low disease activity by DAS28ESR (DAS28ESR ≤ 3.2) receiving TNFi (etanercept, adalimumab and infliximab) stratified their disease activity by RAPID3, then two patients’ groups were defined:target group(RAPID3 with remission 0-3 or low disease activity 3.1-6),non-target group(RAPID3 with moderate 6.1-12 or high disease activity >12). Demographic data, disease duration, autoantibody status, radiological data, concomitant csDMARD therapy was collected. Laboratory measurements included CRP, ESR, calprotectin serum levels, TNFi trough serum levels, and antidrug antibodies (enzyme-linked immunosorbent assay (ELISA) test kit (Calprolab™ Calpro AS, Oslo, Norway, and Promonitor®, Progenika SA, Spain, respectively) according to the manufacturers’ protocol. Pearson´s correlations coefficients were used to identify variables correlating with RAPID3 score. Mixed-effects analyses of covariance (ANCOVAs) models were used to identify factors influencing RAPID3 score.Results:Patients in “target group”have shown a significant lower TJC, pain by VAS 0-10mm, and calprotectin serum levels, but higher TNFi serum trough levels in comparison to “non-target group”. When patients were classified according to RAPID 3 categories, patients in “remission” have shown lower calprotectin serum levels than those classified as in “high disease activity” (0.94 (4.88-0.14) vs. 4.57 (7.97-1.25),p=0.001, respectively). Accordingly, when classified according to pain by VAS 0-10mm, patients with low levels of pain had lower calprotectin serum levels vs. those with severe pain (1.43 (6.33-10.14) vs. 5.16 (8.80-1.25),p=0.009, respectively). When distributed according to PGA (1=very good, 2=good, 3=regular, 4=bad, 5=very bad) patients in “very good” group had lower mean of calprotectin serum levels than those in “very bad” group (0.94 (4.88-0.14) vs. 4.57 (7.97-1.25),p=0.001, respectively). PGA and Pain VAS have shown a strong correlation with RAPID 3 (R20.978, and 0.834,p=0.001, respectively), while calprotectin and TNFi serum trough levels showed a moderate correlation (R20.311, and 0.372,p=0.005, respectively). The multivariate adjusted analysis showed a significant association between Pain and RAPID3 (p<0.001) according to the different covariates (age, gender, anti-CCP positivity, time in remission, SJC, TJC, DAS28ESR). In addition, calprotectin and TNFi trough serum levels were associated with RAPID 3 (p<0.005). Backward selection of variables did not substantially modify the association between RAPID 3 and pain, calprotectin and TNFi trough serum levels.Conclusion:61.7% of RA patients undergoing TNFi classified as in remission or low disease activity by DAS28ESR, self-reported their disease activity as moderate or high by RAPID3. The most significant factor influencing patient’s perception of disease activity is pain (pain VAS and TJC). However, inflammation markers (calprotectin, TNFi serum trough levels) remain statistically significant after fully adjustment by different confounders. Thus, therapies improving these three domains will have a larger impact in patient´s perception of disease activity.