Association between COVID-19 infection and uveitis flare in patients with Behcet's disease, a retrospective multicenter cohort study

Purpose To explore if COVID-19 infection and its subsequent immunosuppressant adjustment as well as previous vaccination status are associated with higher risks of uveitis flare in patients with Behcet's disease. Methods This retrospective multicenter cohort study was conducted in January 2023 among patients with Behcet's uveitis, during the second wave of the COVID-19 pandemic in China, with an anticipated sample size of 250. The primary objective was to examine the association between COVID-19 infection and the occurrence of uveitis flare. The potential impact of other exposures, including the patient's vaccination status and treatment adjustments to the risk of uveitis flare and the course of COVID-19 infection were also analyzed. Results 207 patients with COVID-19 infection and 47 patients without COVID-19 infection were included. A total of 127 uveitis flares occurred in the observational period (14.29 events per 100 person-month). COVID-19 infection was found to be significantly associated with a higher rate of uveitis flare (adjusted rate ratio = 4.8, 95% CI 3.7 to 6.3, P < 0.001). However, neither systemic immunosuppressive adjustment nor COVID-19 vaccination status showed a significant association with uveitis flare or the course of COVID-19 infection. Conclusions This study provides evidence of an association between COVID-19 infection and an increased risk of uveitis flare in patients with Behcet's disease. However, there was no significant evidence to support that baseline immunosuppressive therapy regimens, treatment adjustment after COVID-19 infection, or vaccination status were associated with higher risks of uveitis flare or prolonged COVID-19 course.