Background During the last decade, rheumatoid arthritis (RA) research has mainly focused on early disease, as it has become apparent that early and aggressive treatment can change the long-term outcome of RA. However, as no cure has been identified for RA, most patients in clinical practice have established disease.

Objectives To describe the proportion of patients with established RA (≥5years disease duration) who experience continued joint damage despite receiving aggressive DMARD therapy, and to identify predictors of joint damage in established disease.

Methods We analyzed data from the Brigham Rheumatoid Arthritis Sequential Study (BRASS), an observational RA cohort from an academic medical center in the US. The data collection includes structured joint examinations, serological markers and patient reported outcome measures. Hand and wrist radiographs are acquired at baseline and 2 years and scored by van der Heijde modified Sharp score (vdHSs). We included patients with a disease duration ≥5 years and 2-year radiographic data (n=390). Progression of joint damage was defined as an annual change of ≥1 unit in total vdHSs. We first assessed the association between progressive joint damage and potential predictors such as age, gender, disease duration, treatment, DAS-28 category, subcutaneous nodules, seropositivity (classified as either negative for both RF and anti-CCP, positive for either RF or anti-CCP, or positive for both RF and anti-CCP), BMI category and smoking in univariate logistic regression models. We then built a multivariate regression model, and variables with univariate p-values <0.25 were included in the model building. DMARD treatment and disease duration were forced into the model as covariates.

Results The median (25th percentile, 75th percentile) age of the 390 patients was 60 (52, 67) years and the median disease duration was 17 (10, 27) years. 84% were female and 44% received biologic DMARD treatment. 16% (64 patients) were negative for both RF and anti-CCP, 16% (64) were positive for either and 68% (250) were positive for both RF and anti-CCP. 44% (172) of the patients had progression of joint damage. Older age, longer disease duration, worse disease activity, seropositivity, normal BMI and never smoking had a p-value <0.25 and were included in the model buiding. In multivariate logistic regression analyses, seropositivity was independently associated with joint damage. Positivity for either RF or anti-CCP had an OR (95% confidence interval) of 5.0 (2.2, 11.1) and positivity for both serological markers an OR of 4.1 (2.1, 8.2) for subsequent joint damage. No other independent predictors were identified.

Conclusions Progression of joint damage is still common in RA patients with at least five years disease duration, even in settings where 44% of the patients receive biologic DMARDs. Seropositivity is strongly and independently associated with joint damage, and should potentially influence treatment choices also in the later RA stages.

Disclosure of Interest S. Lillegraven: None Declared, N. Shadick Grant/Research support from: AMGEN, Abbott, Genentech, Cresc. Biosci., MedImm., Biogen Idec, Z. Jabbar-Lopez: None Declared, A. Potapov: None Declared, M. Frits: None Declared, C. Iannaccone Grant/Research support from: Cresc. Biosci., MedImmune, E. Haavardsholm: None Declared, T. Kvien: None Declared, M. Weinblatt Grant/Research support from: Biogen Idec, Cresc. Biosci., MedImm., Consultant for: Biogen Idec, Cresc. Biosci., MedImm., D. Solomon Grant/Research support from: Amgen, Abbott, Lilly, Consultant for: CORRONA