title: Markers of progression to rheumatoid arthritis: discriminative value of the new ACR/EULAR rheumatoid arthritis criteria in a Portuguese population with early polyarthritis.
abstract: OBJECTIVE
  Our goal was to test the performance of the new American College of Rheumatology (ACR)/European League Against Rheumatism (EULAR) criteria for the classification of rheumatoid arthritis (RA) in a cohort of patients with very recent onset polyarthritis.
  
  
  METHODS
  Untreated polyarthritis patients with less than 6 weeks of duration were enrolled. All patients were followed-up in order to establish a definitive diagnosis.
  
  
  RESULTS
  Thirty-seven patients were included. During the follow up 57% of the patients evolved to RA. The median age of the RA-group patients was simi­lar to the median age of the non-RA group [median (IQR) 47 (31-58.5) vs 43 (34-69) years, p=0.74]. At the initial visit the DAS 28 in the RA group was significantly higher than in the non-RA group, as well as the visual analogue scale (VAS), the HAQ and the number of swollen joints. Among the 21 RA patients, 43% presented RF and 28.6% presented anti-citrullinated protein antibody (ACPA) in the first visit. RF and ACPA were not detectable in any of the patients who did not evolve to RA. According to the new ACR/EULAR criteria, 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].
  
  
  CONCLUSIONS
  In our cohort high DAS28, swollen joint count, VAS and HAQ and the presence of RF or ACPA were eventually associated with the evolution into RA. The new ACR/EULAR criteria for the classification of RA seem to perform well in very early RA.
authors.affiliation: Rheumatology Research Unit, Instituto de Medicina Molecular, Faculdade de Medicina da Universidade de Lisboa, Portugal.
authors.forename: Ana Filipa
authors.initials: AF
authors.lastname: Mourão
authors.forename: Helena
authors.initials: H
authors.lastname: Canhão
authors.forename: Rita Aguiar
authors.initials: RA
authors.lastname: Moura
authors.forename: Rita
authors.initials: R
authors.lastname: Cascão
authors.forename: Pamela
authors.initials: P
authors.lastname: Weinmann
authors.forename: Ana
authors.initials: A
authors.lastname: Rodrigues
authors.forename: Joaquim
authors.initials: J
authors.lastname: Polido-Pereira
authors.forename: Catarina
authors.initials: C
authors.lastname: Resende
authors.forename: Susana
authors.initials: S
authors.lastname: Capela
authors.forename: José Alberto
authors.initials: JA
authors.lastname: Silva
authors.forename: João Eurico
authors.initials: JE
authors.lastname: Fonseca
mesh_terms: D001168:Arthritis / Q000150:complications*; D001172:Arthritis, Rheumatoid / Q000145:classification* / Q000209:etiology*; D018450:Disease Progression; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D011174:Portugal; D011446:Prospective Studies; D013997:Time Factors