Accuracy of Wallace criteria for clinical remission in juvenile idiopathic arthritis: a cohort study of 761 consecutive cases.

Abstract

To evaluate disease course and clinical usefulness in some categories of juvenile idiopathic arthritis (JIA) by applying newly developed Wallace definitions of remission off drugs. In a retrospective study, charts of patients with chronic form of primary (idiopathic) arthritis followed from our center since 1970 were reviewed and clinical/laboratory variables were collected for further analysis. The cohort included 761 eligible patients [516 (67.8%) female, 245 (32.2%) male] with JIA. Mean disease onset age (+/- standard deviation) was 6.25 +/- 4.4 years (range 0.5-15.9). Disease mean duration to last visit was 10.02 +/- 4.31 years. Followup mean period was 7.6 +/- 6.4 years (range 1.5-35 yrs). A total of 247 (32.46%) patients achieved remission according to criteria [persistent oligoarthritis 153 (42.9%); extended oligoarthritis 15 (13.1%); seronegative polyarthritis 21 (22.4%); systemic arthritis 33 (33.7%); enthesitis related arthritis (ERA) plus juvenile psoriatic arthritis (JPsA) 25 (33.4%)]. No patients with seropositive polyarthritis achieved remission status (p < 0.001). In remitted patients the mean survival function (+/- standard error of the mean) before relapse calculated by Kaplan-Meier was of 20.9 (+/- 1.3) months overall: 21.7 (+/- 0.46) in persistent oligoarthritis, 25.0 (+/- 6.6) in extended oligoarthritis, 26.7 (+/- 13.2) in seronegative polyarthritis, and 17.6 (+/- 2.44) in ERA+JPsA (p > 0.1). In our cohort about one-third of cases obtained a remission episode in 4 decades of observation, with a significant difference between oligoarthritis and other categories (p < 0.001) using the Kaplan-Meier method; the remission status duration before a relapse has been about 20 months, without a significant difference between JIA categories.