Juvenile idiopathic arthritis during 20 years in Sweden: Characteristics of children, therapy interventions, occurrence of uveitis and ocular complications.

Purpose: To assess and compare the characteristics, therapy interventions, occurrence of uveitis and ocular complications in children with juvenile idiopathic arthritis (JIA) screened and examined for uveitis in Gothenburg, Sweden, over 20 years. Biological immunomodulatory treatment was increasingly used during the second half of the over 20 years.

Methods: Data were retrospectively collected from children with JIA examined for uveitis at the Queen Silvia Children's Hospital between 2012 and 2021. These data were compared with those from a previously published study of children (the first cohort) screened between 2002 and 2011 in the same setting.

Results: The first 10-year cohort (2002-2011) included 299 children, while the second cohort (2012-2021) included 253 children. The median age at JIA diagnosis was 5 years (range: 1-15 years) in both cohorts (p = 0.72), and girls were overrepresented in both groups, 68.9% and 72.7%, respectively (p = 0.32). Oligoarthritis was less frequent in the first cohort than in the second, 57.5% versus 73.9% (p < 0.001). The presence of anti-nuclear antibodies (ANAs) was similar between the cohorts, 57.6% versus 57.9% (p = 0.95). Uveitis occurred less frequently in the first cohort, 10.7% versus 17.0% in the second (p = 0.032). However, uveitis children had (not significantly) more ocular complications in the first cohort, 46.9% versus 34.9% in the second (p = 0.34) and complications were more often affecting both eyes, 73.3% versus 40.0% (p = 0.14). Systemic treatments, particularly biological immunomodulatory therapies, were less commonly used in the first cohort, 24.4% versus 42.7% in the second cohort (p < 0.001).

Conclusion: Over 20 years, we observed a higher occurrence of uveitis in children with JIA in the second 10-year cohort. However, despite being statistically insignificant, we found fewer ocular complications, and less frequent in both eyes. This may indicate a beneficial effect of the increased use of biological immunomodulatory therapy.