Cumulative incidence of macular edema in non-infectious uveitis indicates an early therapeutic window.

Purpose: Uveitis-associated macular edema (UME) is a significant cause of visual impairment in non-infectious uveitis (NIU). However, the UME incidence remains unclear. Here, we evaluated the cumulative incidence of UME.

Methods: Medical records of patients registered with a uveitis diagnosis code between 2010 and2024 were assessed to validate uveitis diagnoses of the patient registry of the North Denmark Region, a region of 600 000 inhabitants. Positive predictive values (PPV) were calculated for uveitis diagnosis and subtypes. The data from medical records were used to estimate prevalence, incidence and cumulative incidence of UME. The group differences were analysed by chi-squared test and cox proportional-hazards model.

Results: A total of 1476 medical records were reviewed. The PPV for a uveitis diagnosis was 92.2% (95% CI: 90.7-93.5) and 88.4% (95% Cl: 86.8-90.0) for uveitis subtypes. Among 1218 patients with NIU, 6.9% had UME at referral. During follow-up, 8.3% of the NIU patients developed UME with an incidence rate of 1.4 per 100 person-years (95% CI: 1.3-1.7) and a cumulative incidence of 10.7% (95% CI: 8.5-13.5). A higher incidence of UME was observed for patients with bilateral uveitis, systemic disease, intermediate uveitis, posterior uveitis and panuveitis (p < 0.001). A substantial increase in the cumulative incidence of UME was observed in the first 2 years post-referral.

Conclusion: The high PPV supported the registry's reliability for uveitis research. UME was frequently present at the first uveitis clinic visit. NIU patients were at heightened risk of UME within the first 2 years after referral, indicating an early time window with a critical need for inflammation management.