Persistence of mild, early inflammatory arthritis - The importance of disease duration, rheumatoid factor, and the shared epitope

Objective, To determine the factors that predict clinical outcome at 6 mont hs for patients with mild, early inflammatory arthritis. Methods, Sixty-three patients with mild, untreated, early arthritis were gi ven a single dose of corticosteroids at presentation, Administration was in tramuscular if disease was polyarticular (n = 53) or intraarticular if pati ents had <5 synovitic joints (n = 10), The primary outcome measure was clin ical disease remission or persistence of arthritis at 6 months following in jection, Results. At 6 months following injection, 49 of the 63 patients (78%) had p ersistent inflammatory joint disease. The other 14 (22%) had clinical disea se remission, Regression analysis showed that only disease duration was sig nificantly associated with persistent arthritis (P < 0.05), The other signi ficant factor (by chi-square test) was the presence of the shared epitope ( SE), Of the patients fulfilling the American College of Rheumatology (ACR) criteria at presentation (51% of the total), 53% with disease duration of l ess than or equal to 12 weeks at presentation had persistent disease 6 mont hs later, compared with 94% of those who presented with disease duration of >12 weeks, Conclusion. The strongest predictor of persistent disease was a disease dur ation of >12 weeks. Rheumatoid factor and SE were also predictors to a less er extent. Patients who both fulfilled the ACR classification criteria for rheumatoid arthritis (RA) and had a short disease duration included some wi th an excellent prognosis. Therefore, 12 weeks may be a more appropriate di sease duration to use for the RA classification criteria. Administering a b olus of corticosteroids may be a useful diagnostic/therapeutic approach.