PREDICTING FUTURE RESPONSE TO TUMOR NECROSIS FACTOR INHIBITORS BY THE DISTRIBUTION OF AFFECTED JOINTS IN RHEUMATOID ARTHRITIS PATIENTS

Background Achieving remission is essential for avoiding joint destruction and disability in patients with rheumatoid arthritis (RA). Tumor necrosis factor inhibitors (TNFi) therapies represent an important advancement in therapy for RA. However, there remains a proportion of patients who do not improve despite TNFi therapies. Recently, Terao et al. (1) analyzed the distribution of affected joints in the 28 joints in patients with RA and showed that RA patients can be categorized into three subgroups based on their affected joints (1: PIP joints dominant, 2: MCP joints dominant, and 3: large joints with wrist joints dominant). Nevertheless, it remains obscure whether these three subgroups were correlated with treatment response. Objectives To analyze the prognostic significance of data collected at starting TNFi, especially the distribution of affected joints, to predict remission in RA patients at week 16. Methods Data from 62 TNFi-treated patients with RA at the baseline were used as variables to predict remission. The disease status at the baseline and week 16 was assessed using the disease activity score (DAS 28) and patients achieving remission at week 16 were identified according to EULAR criteria (DAS 28 Results The patients were classified into 11 (18%) of PIPd group, 19 (31%) of MCPd group, and 32 (52%) of L-Wd group according to their affected joints. Univariate analyses revealed that patients who achieved remission showed significantly lower levels of DAS28, mHAQ, ESR, and CRP, and shorter disease duration than those without remission. It was also disclosed that patients in PIPd group were more likely to achieve remission than patients in MCPd group or L-Wd group. The baseline characteristics including concurrent use of MTX and/or GC, previous biologics therapy, tender joint count, and swollen joint count were not associated with response to TNFi. Among the baseline characteristics, lower levels of ESR and belonging to PIPd group were independently correlated with achievement of remission in multivariate analysis (p=0.012 and 0.028, respectively). Conclusions We suggested that RA patients predominantly affected with PIP joints were likely to achieve remission in response to TNFi. The distribution of affected joints could predict future response to TNFi in RA patients. References Terao C et al. PLoS One. 2013; 8: e59341. Disclosure of Interest None declared DOI 10.1136/annrheumdis-2014-eular.1980