Prognostic markers in rheumatoid arthritis and classification of antirheumatic therapies.

Rheumatoid arthritis is characterised by a generally poor outcome and high morbidity, and has a variable course. Identifying those patients most likely to have a poor prognosis is of key clinical significance. Disease outcome can be predicted from a variety of prognostic markers. Some of these are simple demographic features of the patients, and include age, disease duration, and gender. Others are more specific features of rheumatoid arthritis, including the presence of early erosive changes on plain radiographs, high rheumatoid factor titres, high levels of C-reactive protein, and high scores for disease activity. Although no single marker has adequate specificity or sensitivity to form the basis of clinical decisions, the presence of several is predictive of more severe disease. Thus, patients with early erosive damage who are seropositive for rheumatoid factor and have high levels of C-reactive protein are more likely to have a poor outcome. New markers and imaging techniques are likely to become the prognostic tools for the future. These include genetic markers, and a combination of magnetic resonance imaging and dual energy x-ray absorption scans for localised osteoporosis.