Background New ACR/EULAR criteria for the classification of rheumatoid arthritis (RA) were recently proposed.
Objectives The aim of this analysis was to examine the impact of fulfilling the 2010 ACR/EULAR criteria at the initial visit on long-term progression of disease and radiographic progression.
Methods For this observational cohort study within the Swiss RA registry SCQM, we included patients suffering from early RA or undifferentiated arthritis (UA, disease duration ≤1 year), as defined by the treating rheumatologist, who had not received any previous DMARDs. Baseline diagnosis of RA/UA was reassessed according to the 2010 ACR/EULAR criteria at baseline. Patients were separated into 2 groups depending on whether or not they fulfilled the 2010 ACR/EULAR criteria at baseline (≥ 6 points versus < 6 points). The primary outcome measures were the DAS 28 and erosions as measured by the Ratingen score over time.
Results A total number 592 patients was analysed. 352 of them fulfilled the 2010 ACR/EULAR at baseline, 240 were not classifiable as RA according to the new criteria at baseline. The score calculated by the new ACR/EULAR criteria correlated with disease activity at disease onset. Treatment was initiated with DMARDs, mostly MTX, in all patients. There were no significant differences in the therapeutic strategies between patients fulfilling the classification criteria or not. The patients fulfilling ACR/EULAR criteria at baseline developed a 39.1%reduction of DAS 28 scores, as compared to a 33.6%reduction in ACR/EULAR-negative patients after 6 months, independent of their respective treatments. After 1 year of follow-up no differences were found comparing the mean DAS28 scores in the 2 groups. Average radiographic progression was higher among ACR/EULAR-positive patients (progression of Ratingen score/year 0.50 vs. 0.32, resp., p=0.03) after 3 years of follow up.
Conclusions The 2010 ACR/EULAR criteria appeared to select a subset of patients among early RA/UA patients with a favourable clinical response to conventional anti-rheumatic therapy. Despite this therapy, radiographic progression was higher in 2010 ACR/EULAR positive patients.
Disclosure of Interest None Declared