Female sex and oligoarthritis category are not risk factors for uveitis in Italian children with juvenile idiopathic arthritis

Objective. To investigate the risk factors for chronic anterior uveitis in patients with juvenile idiopathic arthritis (JIA). Methods. The clinical charts of patients followed between January 1987 and December 2011 were reviewed to establish whether they had uveitis. Inclusion criteria were a diagnosis of JIA and a disease category of persistent oligoarthritis, extended oligoarthritis, rheumatoid factor-negative polyarthritis, psoriatic arthritis, or undifferentiated arthritis. Risk factors included sex, age at arthritis onset, disease category, and antinuclear antibody (ANA) status. The association of risk factors with occurrence of uveitis was evaluated by survival analysis, with first episode of uveitis as the event of interest, and Cox regression analysis. Results. Of a total of 1189 patients, 278 (23.4%) had uveitis a median of 1.1 years after onset of arthritis. There was no difference in the cumulative probability of developing uveitis between males and females and between patients belonging to different JIA categories, whereas uveitis was strongly associated with age at arthritis onset ≤ 3.5 years and positive ANA. Patients possessing the latter 2 factors in combination had a greater probability of having uveitis than patients who had either of them alone. Conclusion. In our patients, the risk of uveitis was related to younger age at onset of arthritis and presence of ANA, but not to female sex and disease category. This finding suggests that the patients who require the most intensive ophthalmologic screening are those who have early-onset JIA and are ANA-positive, regardless of their sex or disease subtype.