Disease activity and dropout in young persons with juvenile idiopathic arthritis in transition of care: a longitudinal observational study.

Objectives: Reaching a certain age, juvenile idiopathic arthritis (JIA) patients in paediatric care are transferred to adult care. An increased disease activity after transfer and increased dropout has been suggested, however, evidence is scarce. Our aim is to determine whether the process of transition is associated with increased disease-activity and dropout, and to identify associated factors.

Methods: During a 3-year prospective transition cohort study, paediatric patients (14-17yrs) were transferred to adult care. Paediatric (10-13yrs) and adult JIA patients (18-27yrs) were used as control groups. Demographic and disease-related items were obtained yearly. Non-parametric tests were used to compare differences between the groups and mixed models to evaluate disease activity over time, measured by JADAS27 and DAS28. Dropout was defined as not attending the clinic for 2 consecutive visits.

Results: Groups did not differ regarding baseline variables of subtype, gender, uveitis, ANA-, RF- or HLA B27-positivity and current or past DMARD use. Median disease activity was not different between groups during follow-up. Transfer was not associated with disease activity. Dropout rate was 12%, and was significantly higher in patients under transition (22%) compared with paediatric (3%) and adult care (10%). Patients who dropped out had significantly lower disease activity at baseline and were using less MTX, but did not differ regarding subtype, ANA, RF and HLA-B27.

Conclusions: The process of transition in JIA is not associated with an increase in disease activity, however, this period carries a risk for drop out especially in patients with low disease activity.