Nationwide incidence of blindness in South Korea: a 12-year study from 2002 to 2013

Abstract

Importance: Blindness is an important public health issue.

Background: The background of the study is to determine the incidence of blindness in South Korea.

Design: Nationwide population-based retrospective study.

Participants: All individuals from South Korea (n = 47 516 098).

Methods: Patients confirmed with legal blindness based on the worse-seeing and better-seeing eyes between 1 January 2002 and 31 December 2013 were included. The Korean National Health Insurance Service (KNHIS) database was used. Using the World Health Organization definition, blindness was defined as best-corrected visual acuity in the worse-seeing and better-seeing eyes of <20/400. The mean incidence of blindness during the 12-year period was estimated. The population of South Korea was estimated using census data in 2005 and 2010.

Main outcome measures: The total number of legal blindness cases in the KNHIS database.

Results: We identified 195 004 and 20 492 cases of newly developed legal blindness based on the worse-seeing and better-seeing eyes, respectively, and the mean incidences of blindness were 34.2 and 3.6 cases/100 000 person-years, respectively. The prevalence of blindness based on the worse-seeing and better-seeing eyes was 425.3 and 57.7 cases/100 000 persons, respectively. The incidence of blindness based on the worse-seeing eye was higher in men than in women overall. Additionally, the incidence increased with age and showed a decreasing trend from 2002 to 2013.

Conclusions and relevance: The prevalence of blindness showed an increasing trend from 2002 to 2013. The findings of our study will help in the assessment of the blindness-related socio-economic burden and in healthcare planning.

Keywords: blindness; epidemiology; incidence.