Background: Anterior uveitis (AU) is a significant concern in patients with ankylosing spondylitis (AS), and the choice of tumor necrosis factor inhibitors (TNFi) as a treatment modality raises questions regarding its effects on AU. We compared the effects of TNFi on AU in patients with AS. Methods: Patients diagnosed with AS and treated with at least one TNFi, including anti-TNFα antibodies (adalimumab and infliximab) or a soluble TNF receptor molecule (etanercept), between January 2010 and December 2022, were retrospectively reviewed. We compared the recurrence rate of AU in patients with a history of uveitis and the incidence of new-onset AU in those without a history of uveitis among the three TNFi groups. We also compared the effects of two different TNFi agents in patients who underwent TNFi switching. Results: Within two years of treatment initiation, there was no significant difference in AU recurrence among the three TNFi groups. However, the incidence of new-onset AU was significantly higher in the etanercept group than in the adalimumab group (26.4% vs. 6.3%; p = 0.024). After two years, the AU recurrence rate was significantly lower in the adalimumab group than in the other groups (p < 0.001). Among patients who underwent anti-TNFi switching, adalimumab treatment was associated with a significantly lower incidence of uveitis than etanercept (p = 0.023). Conclusion: In the short-term period following TNFi therapy, etanercept induced new-onset AU more frequently than adalimumab in patients with AS. Adalimumab recipients experienced fewer AU recurrences during the subsequent long-term period compared to other TNFi recipients.
Keywords: ankylosing spondylitis; anterior uveitis; tumor necrosis factor inhibitors.