Outcome and predictive factors in juvenile rheumatoid arthritis and juvenile spondyloarthropathy

To describe outcome and determine predictive factors in juvenile rheumatoid arthritis (JRA) and juvenile spondyloarthopathy (JSpA).

Seventy-two children with chronic arthritis were studied on first admission to the pediatric rheumatology clinic and after a mean of 9.7 +/- 1.8 yrs of disease duration.

At followup, 53 patients had JRA and 19 had JSpA. Eleven (21%) of the patients with JRA did not meet the criteria for JRA on first admission, and 12 (22%) of 54 children diagnosed as having JRA on first admission were later reclassified as having another disease. Remission occurred in 43 (60%) of the 72 patients with JRA and JSpA. Forty-four patients (60%) reported no disability by the childhood or adult Health Assessment Questionnaire and 18 patients (25%) had developed joint erosions. Disease modifying antirheumatic drugs (DMARD) were given to 49 patients (68%) after a median of 0.8 yrs (range 0.2-10.8) disease duration. The patients who developed erosions and disability tended to have started treatment later than those who did not (NS). Active disease 5 years after onset was a predictor of disability in JRA and JSpA (OR 4.5, 95% CI 1.6-12.5). Predictors of joint erosions were long duration of elevated erythrocyte sedimentation rate (ESR) (OR 3.7/yr of elevated ESR, 95% CI 1.9-7.2), long disease duration before first admission (OR 1.5/yr of duration, 95% CI 1.1-2.1), long disease duration before treatment with DMARD (OR 1.8, 95% CI 1.0-3.3), and IgM rheumatoid factor (OR 12 x 10(4), 95% CI 0-1.2 x 10[52]).

The longterm outcome in JRA and JSpA was more favorable than previously reported. This may be explained by less selection in favor of severely diseased patients and by the use of early aggressive treatment regimes.