Risk of uveitis in patients with psoriasis in Korea: A nationwide population-based cohort study.

BACKGROUND: Evidence for the association between psoriasis and uveitis according to the severity of psoriasis including psoriatic arthritis (PsA) and type of uveitis is lacking, and there are no data on the frequency or timing of recurrence of uveitis in patients with psoriasis. OBJECTIVES: We aimed to evaluate the risk of first occurrence and recurrence of uveitis in patients with psoriasis in the Korean population. We further evaluated the risk of uveitis according to the severity of psoriasis, comorbidity of PsA and location of uveitis. METHODS: In a nationwide retrospective cohort study, we compared 317,940 adult patients who had psoriasis with 635,880 matched controls. Incidence rates (IRs) and estimated IR ratios of the first occurrence and recurrence of uveitis were calculated using survival analysis and Poisson regression, respectively. RESULTS: The rate of uveitis incidence and uveitis recurrence in patients with psoriasis was 1.18 and 2.31 per 1000 person-years, respectively. Compared to the controls, the IR ratios of development and recurrence of uveitis in patients with psoriasis were 1.14 (95% CI 1.08, 1.2) and 1.16 (95% CI 1.12, 1.21), respectively. The recurrence rate of uveitis was highest within 3 years after the onset of psoriasis. The corresponding IR ratios for uveitis recurrence in patients with mild psoriasis, severe psoriasis and PsA were 1.11 (1.06, 1.16), 1.24 (1.16, 1.33) and 1.49 (1.31, 1.7), respectively. Patients with psoriasis had an increased risk of recurrence of anterior uveitis, and patients with both psoriasis and PsA had an increased risk of recurrence of both anterior-uveitis and panuveitis. CONCLUSIONS: Patients with psoriasis had a higher risk of both development and recurrence of uveitis, especially with severe psoriasis and PsA. The timing of uveitis recurrence was related to the onset of psoriasis, and patients who had psoriasis with PsA had an increased risk of vision-threatening panuveitis.