Study and Monitoring of Early Undifferentiated Arthritis

All patients were referred to each regional center every 6 months during the first 2 years, then every year. Procedures were set up to avoid patients lost to followup as much as possible. At baseline and at each visit, we recorded data for a set of clinical and biological variables recommended for the management of early arthritis. At each visit, rheumatoid arthritis was classified according to the 1987 American College of Rheumatology (ACR) criteria and retrospectively to the 2010 ACR/European League Against Rheumatism (EULAR) criteria. At each visit, patients completed function and quality-of-life self-administered questionnaires including the Health Assessment Questionnaire-Disability Index (HAQ-DI), Arthritis Impact Measurement Scales version 2 short form, a medico economic questionnaire, and globally assessed disease, pain at rest and pain during motion on a visual analog scale (VAS). Patients underwent radiographs of the hand and wrist (face) and foot (face and oblique). Radiographs were stored in the radiological coordinating center (Brest) and then were evaluated by the van der Heijde-modified Sharp score. Serum, DNA, urine, were collected at baseline. Serum and urine were also obtained at each follow-up visit. They were then sent and stored in adequate and definite conditions in the biological coordinating centre (Paris-Bichat).