Predictors of chronicity and the discriminative value of the new ACR/EULAR rheumatoid arthritis classification criteria in an untreated polyarthritis cohort with less than 6 weeks of disease duration
- A F Mourão†1,
- H Canhão†1, 2,
- R A Moura1,
- R Cascão1,
- P Weinmann1,
- A Rodrigues1, 2,
- J Pereira1, 2,
- C Resende2,
- S Capela2,
- J A Pereira da Silva2 and
- J E Fonseca1, 2
© Mourão et al; licensee BioMed Central Ltd. 2010
Published: 25 November 2010
1. To find predictors of progression to RA in a cohort of patients with a very recent onset polyarthritis. 2. To test the performance of the new ACR/EULAR criteria for the classification of RA in this population.
Patients with polyarthritis with less than 6 weeks of duration were enrolled during a period of 4 years. They were not exposed previously to corticosteroids or DMARDs. All patients were prospectively followed-up in order to establish a definitive clinical diagnosis. A protocol was applied, including demographic and clinical data, and a blood sample was collected to assess ESR, RF and ACPA levels, before any treatment was started.
Baseline differences between patients who latter evolved into RA (RA-group), comparing to who did not (non-RA group).
Total involved joints
Among the 21 RA patients, 21 were evaluated for RF and 17 for ACPA in the first visit. Of these, 45% presented RF and 37.5% presented ACPA. RF and ACPA were not detectable in any of the patients who did not evolve to RA.
According to the new criteria for the classification of RA, the mean total score of the RA group at baseline was significantly higher than the non-RA group (median (IQR) 6 (4.5-8) vs 4.5 (2.2-6), p=0,007). Interestingly, the highest score reached in the non-RA patients was 6 points, the cut-off point to classify patients as having RA.
In our cohort a high DAS28 score, a high number of swollen joints, a low functional status and the presence of RF or ACPA are associated with the future evolution into RA. The new ACR/EULAR criteria for the classification of RA seem to identify the majority of patients that will evolve to RA.
This article is published under license to BioMed Central Ltd.