Predictors of outcome in patients with oligoarthritis: results of a protocol of intraarticular corticosteroids to all clinically active joints.

Objective: To determine the outcome and the factors that predict the persistence of synovitis following intraarticular corticosteroid injections in patients with recent-onset oligoarthritis.

Methods: Fifty-one patients with < or =5 joints with synovitis (disease duration < or =12 months) were treated with intraarticular injections of methylprednisolone into all joints with clinical synovitis. Predictors of outcome were sought, with the primary end point a complete response (no synovitis on clinical examination) at 12 weeks.

Results: Patient's and physician's assessments of disease activity, the swollen joint count, and function (by Health Assessment Questionnaire) were all significantly improved at 12 weeks (P < 0.001). Twenty-nine patients (57%) were judged to have had a complete response at 2 weeks. The best predictor of response at 12 and 26 weeks was the presence or absence of synovitis at 2 weeks (P = 0.002 and P = 0.004, respectively). At 52 weeks of followup, nearly 50% of the patients still had evidence of synovitis.

Conclusion: Intraarticular corticosteroids are an effective treatment for early oligoarthritis, but there is still a high level of long-term morbidity. Failure to respond by 2 weeks indicates a high likelihood of persistent disease, and this is relevant when producing management guidelines and selecting patients for studies focusing on early intervention.