Background Systemic-onset juvenile idiopathic arthritis (soJIA) is a rare subtype of juvenile idiopathic arthritis (JIA). Data on outcome of patients with soJIA are limited. Most other cohort studies describe a higher risk of progression to severe disability, growth failure and poorer functional outcome compared to the other JIA subgroups.
Objectives to assess outcome in systemic-onset juvenile idiopathic arthritis (soJIA) over the last years.
Methods Data were analyzed from the German National paediatric rheumatologic database (NPRD) of the years 2000 to 2010. All patients with soJIA and a minimum follow-up period of 3 years were included. Outcome variables were disease activity measured by the Juvenile Arthritis Disease Activity Score (JADAS), physician`s global rating of health status (numeric rating scale (NRS) and functional capacity in daily living activities documented by the Childhood Health Assessment Questionnaire (CHAQ). Influencing factors for achieving an inactive disease (physicians´ global assessment, NRS=0) were analysed by logistic regression. Body heights of soJIA patients were compared with those of age- and sex-machted controls from the general population (German Health Interview and Examination Survey for Children and Adolescents) (1).
Results Data of 100 consecutive patients with early soJIA (disease duration ≤12 months) were analysed. At baseline, the patients (47% female) with a median age of 7 years had a mean CHAQ-Score of 0.3 and a mean JADAS of 8.4. In the first year of the disease 74.5% of patients were treated with glucocorticoids and 66.3% with DMARDs (60% Methotrexate, 3.2% biologic drugs). At the three-year follow-up the disease was inactive in 70% of patients, the mean JADAS was 1.9 and the CHAQ 0.1, one in four patients still received glucocorticoids and every second DMARDs (11.9% biologic drugs).
Height SDS for chronologic age (z-score) was significantly reduced in 15% of soJIA patients (below the second standard deviation) compared to the control group (2%) from the general population (p<0.001).
JADAS and CHAQ at baseline were of predictive value in terms of reaching an inactive disease (p = < 0.05). Functional capacity at baseline was a predictor for disease activity, JADAS, CHAQ, pain and patient overall well-being at follow up (p < 0.05). The higher the functional limitation at baseline was, the higher were disease activity, the JADAS and functional limitation, and the stronger patients suffered from pain and the more limited was their overall well-being at follow-up.
Conclusions Patients with soJIA experience improvement regarding disease activity and functional outcome within three years of paediatric rheumatology care. However, length growth was significantly reduced in patients with soJIA. Given the new treatment options with biologic drugs it can be expected, that the prognosis of soJIA patients will further improve.
Public Use File KiGGS, The German Health Survey for Children and Adolescents 2003-2006. 2008. Robert Koch Institute, Berlin (Germany). Ref Type: Online Source
Disclosure of Interest None Declared