Prospective Determination of the Incidence and Risk Factors of New-Onset Uveitis in Juvenile Idiopathic Arthritis: The Research in Arthritis in Canadian Children Emphasizing Outcomes Cohort.

OBJECTIVE: Identification of the incidence of Juvenile Idiopathic Arthritis (JIA)-associated uveitis and its risk factors is essential to optimize early detection. Data from the Research in Arthritis in Canadian Children Emphasizing Outcomes (ReACCh-Out) inception cohort were used to estimate the annual incidence of new-onset uveitis following JIA diagnosis and identify associated risk factors.

METHODS: Data were reported every 6 months for 2 years, then yearly to 5 years. Incidence was determined by Kaplan-Meier estimators with time of JIA diagnosis as the reference point. Univariate log-rank analysis identified risk factors and Cox regression determined independent predictors.

RESULTS: In total, 1183 patients enrolled within 6 months of JIA diagnosis met inclusion criteria, median age (IQR) at diagnosis of 9.0 (3.8-12.9) years, median follow-up of 35.2 (22.7-48.3) months. Of these, 87 patients developed uveitis after enrollment. The incidence of new-onset uveitis was 2.8% per year (95% CI 2.0-3.5) in the first 5 years. The annual incidence decreased during follow-up but remained at 2.1% (95% CI 0, 4.5) in the 5th year although confidence intervals overlapped. Uveitis was associated with young age (< 7 years) at JIA diagnosis (HR=8.29, p<0.001), positive ANA (HR=3.20, p<0.001), oligoarthritis (HR=2.45, p=0.002), polyarthritis RF-negative (HR=1.65, p=0.002), female sex (HR=1.80, p=0.02). In multivariable analysis, only young age at JIA diagnosis and ANA positivity were independent predictors of uveitis.

CONCLUSION: Vigilant uveitis screening should continue for at least 5 years after JIA diagnosis and priority for screening placed on young age (< 7 years) at JIA diagnosis and a positive ANA. This article is protected by copyright. All rights reserved.