Retention in Rheumatology Care Across the Juvenile Idiopathic Arthritis Care Pathway: From Diagnosis Through Transition

Objectives Juvenile idiopathic arthritis (JIA) comprises a heterogeneous group of childhood-onset arthritides, many of whom require continuous pediatric rheumatology care and transition to adult rheumatologists. We examined retention in pediatric rheumatology care from childhood through adulthood and transition times between pediatric and adult rheumatology care. Methods This was a population-based longitudinal study following an inception cohort of children/adolescents with JIA diagnosed between 2010 and 2018, and followed until January 2024. JIA patients were defined as those with at least 3 diagnosis codes for inflammatory arthritis (ICD 714, 720, 721) over 2 years, with at least 1 by a pediatric rheumatologist before their 16th birthday. Patients were followed from their first pediatric rheumatologist visit until the earliest of their first adult rheumatologist visit, 23rd birthday, death, out-migration or study end date. For each follow-up year, we classified patients as engaged in care (at least 1 pediatric rheumatologist visit), out of care (no visits that year), lost to follow-up (after 3-year gap), re-engaged in care (after gap year(s)), or transferred to adult rheumatology care, and assessed for longitudinal transitions between care states. For JIA patients transitioning to adult rheumatology care, we described the interval between their last pediatric rheumatologist visit prior to their first adult rheumatologist visit. Results Among 2,919 patients with JIA, the median (IQR) age at diagnosis was 11 (6-14) years and 63% were female. By 5 years of follow-up, only 42% of patients were engaged in pediatric rheumatology care, with 31% lost to follow-up (Figure). Among 923 patients who successfully transitioned to adult rheumatologists, 601 (65%) where seen by adult rheumatology within 6 months of their last pediatric rheumatology visit (throughout the entire study period), and the mean (SD) interval between the last pediatric and first adult visit decreased from 584 (891) days at the start of the observation period to 150 (289) by end of the study period. Figure. Sankey diagram representing JIA patient flow between states over 5-years. Conclusion This study found that nearly half of JIA patients do not remain continuously engaged in pediatric rheumatology care through to transition to adult rheumatology care. However, transition times from pediatric to adult rheumatology care improved over calendar time. Given the limitations of health administrative data with few diagnosis codes to identify all JIA subtypes (some of whom do not require transition), further research requires more detailed clinical data to identify which JIA patients are experiencing gaps in care and further strengthen retention and successful transitions to adult care.