Prediction of Disease Outcome in Early Arthritis

Abstract

The terms early arthritis, undifferentiated arthritis (UA) and early rheumatoid arthritis (RA) are not completely synonymous. They refer to slightly different sets of patients with intrinsic differences in the disease outcome. UA refers to arthritis that cannot be classified according to current criteria. The disease course of UA is variable, 40–50% remit spontaneously, whereas about one third of the UA-patients are in an early phase of RA. These UA-patients provide an opportunity, as the disease process in UA is less established and treatment in this early phase may halt the progression towards RA. To identify the UA-patients who will develop RA a prediction rule has recently been developed. This rule estimates the chance to develop RA in individual UA-patients and its predictive ability is established in several countries throughout the world. Another initiative to identify RA patients early is the development of new classification criteria for RA. The sensitivity and specificity for early RA of these criteria are not known yet. Clinical trials evaluating the effects of DMARD-therapy in UA are still scarce but are needed in order to derive a personalized medicine for UA-patients.