The Canadian Alliance of Pediatric Rheumatology Investigators National Juvenile Idiopathic Arthritis Registry

1. BACKGROUND JIA includes all chronic arthritis of unknown cause starting before the age of 16. JIA is the most common rheumatic disease of childhood, affecting approximately 1 in 1,000 Canadian children. Despite trends to more favorable outcomes, JIA continues to have disabling sequelae that reduce mobility, quality of life and future productivity, affecting the child, their families and society as a whole. After a diagnosis of JIA, families have many questions about the prognosis of their child, treatments that may be required and their potential side-effects. Despite numerous studies, our ability to answer these questions remains limited.

International League of Associations for Rheumatology (ILAR) criteria classify children with JIA into seven categories based on clinical manifestations and laboratory tests. Current practice recommendations propose use of medications tailored according to JIA category or according to treatment groups defined by number of joints affected and features of poor prognosis. In general, initial treatment with intraarticular corticosteroids and nonsteroidal anti-inflammatory drugs (NSAIDs) is recommended for JIA affecting a few joints; while methotrexate and biologic agents are recommended when many joints are affected and for children with features of poor prognosis.

CAPRI is the collaborative network of all pediatric rheumatology investigators across Canada, with an outstanding track record of successful collaboration in a number of research projects. Since 2005 CAPRI investigators have worked on a project called ReACCH-Out, a team grant funded by the Canadian Institutes of Health Research (CIHR) to study the impact of arthritis on Canadian children. CAPRI developed a robust web-based longitudinal data base and enrolled 1,500 newly diagnosed children with JIA during a five year period. This study has resulted in one of the largest longitudinal JIA cohorts in the world and six published scientific manuscripts to date. Most importantly it has provided essential new answers about disease presentation and short to medium-term prognosis. The initial study was leveraged into two subsequent studies also funded by CIHR: Biologically Based Outcomes Predictors in JIA (BBOP) and Linking Exercise, Activity, and Pathophysiology in Canadian children with Arthritis (LEAP).

Continuation of this effort with a new registry can illuminate longer term prognosis for JIA patients. The rapidly changing landscape of available therapies necessitates maintenance and extension of the registry to elucidate the changing prognosis in different therapeutic eras, and to enable contemporary prognostic counseling to new patients and their families.

In April 2015, The Arthritis Society provided an infrastructure award to continue, expand and strengthen a harmonized Canadian registry of patients with JIA, to support pediatric rheumatology research. This award has been enriched with other sources to include assessment of medication adverse events, thus providing the funding that will be used for this CAPRI national JIA registry. 2. GOALS AND PRINCIPLES