Nationwide Trends in the Incidence and Use of Immunosuppressive Therapy for Non-Infectious Non-Anterior Uveitis in South Korea (2010–2021)

To investigate the incidence of non-infectious non-anterior uveitis (NINAU) based on steroid prescriptions recorded in the Korean National Health Insurance Service (KNHIS) database, covering nearly the entire Korean population. Data were collected from patients diagnosed with uveitis who visited clinics between 2010 and 2021. Patients categorized as having NINAU prescribed steroids within one month were defined as “true NINAU.” We compared the demographics and underlying comorbidities between patients treated with steroids alone and those receiving immunomodulatory therapy (IMT). Additionally, we analysed trends in IMT use. Among 38 271 patients with NINAU, the average incidence (per 100, 000 persons) was 6.2 (95% confidence interval, 6.1–6.3) increasing from 2010 to 2017 before gradually declining. Incidence rates increased with age. Most patients with NINAU were managed with systemic corticosteroids alone (approximately 89%); however, steroid-sparing IMT use increased from 2010 to 2021. By 2021, nearly one-third of patients treated with IMT required combination regimens, reflecting increased therapeutic complexity in refractory cases. We estimated the nationwide incidence of NINAU from the KNHIS database by incorporating steroid prescriptions as an additional criterion. These findings could help inform the national impact of NINAU in South Korea and may have implications for other countries.