The best predictors of rapidly progressing RA are currently the number of swollen joints, the presence of autoantibodies (high-titre rheumatoid factor and anti-citrullinated peptide antibodies) and elevated acute-phase response (as measured by the erythrocyte sedimentation rate (ESR) or C-reactive protein (CRP) level) [47-50]. Here, CRP is linked to rheumatoid arthritis.