Patients with rheumatoid arthritis (RA) with positive antibodies against carbamylated proteins (anti-CarP) have a more severe clinical course. The primary objective of this study in adult subject with RA is as follows: To explore the clinical differences in activity indexes (Disease Activity Score of 28 joints with Erythro Sedimentaion Rate (DAS28-ESR)) at 6, 12 and 18 months of follow up according the anti-CarP antibodies status.