Identification of early risk factors for anti-citrullinated-protein-antibody positive rheumatoid arthritis-a prospective cohort study.

We propose a high-Risk-RA phase characterized by presence of ACPA reactivity, tenosynovitis, IL6, and IL15-Rα and suggest that these factors need to be further investigated for their biological effects and clinical values, to identify individuals at particular low risk and high risk for arthritis progression.