Recent Changes in Trends of Nationwide Incidence of Glaucoma and Associated Visual Impairment in South Korea

Background/Objectives: We analyzed recent changes in the incidence of glaucoma and associated visual impairment (VI) in Korea over a 16-year period. Methods: We utilized nationwide, longitudinal cohort data from the Korea National Health Insurance System (KNHIS) National Health Screening Cohort from 2004 to 2019 to evaluate the age-standardized incidence rate (SIR) of glaucoma and glaucoma-related VI. VI was determined based on KNHIS health examinations and the National Registry for Visual Disability. The incidence rates were estimated per 100,000 person-years. Joinpoint regression analysis was applied to assess significant changes in incidence trends, and subgroup analyses were conducted by age and sex. Results: The age-SIR of glaucoma increased from 864.1 per 100,000 in 2004 to a peak of 1101.1 in 2016, followed by a decline to 978.9 in 2019. Joinpoint regression identified a significant rise from 2007 to 2015 (annual percent change [APC]: +3.92%), with a subsequent decline (APC: –3.30%). The incidence of glaucoma-related severe VI decreased from 26.23 per 100,000 in 2004 to 8.76 in 2012, remaining stable thereafter at 12.49 in 2019. The VI-to-incidence ratio also declined from 0.030 in 2004 to 0.009 in 2012, which remained stable thereafter at 0.013 in 2019. Females consistently exhibited higher glaucoma incidence but lower VI rates than males. Conclusions: These recent trends highlight the evolving landscape of glaucoma epidemiology in Korea and underscore the need for sustained early detection efforts and optimized patient management.