Prevalence and Incidence of Keratoconus in South Korea: A Nationwide Population-based Study

Abstract

To determine the prevalence and incidence of keratoconus in South Korea. A nationwide, population-based, retrospective study of keratoconus in the entire South Korean population (N= 47 990 761) from 2009 to 2014 was conducted using data from the Korean Health Insurance Review and Assessment (HIRA) database. We identified patients with ophthalmologist-confirmed keratoconus using the HIRA database, and estimated keratoconus prevalence and incidence rates, both overall and according to age and sex. Of 47 990 761 subjects, 17 931 had keratoconus during the 6-year period. The prevalence in the general population was 37.4 cases (95% confidence interval [CI]: 36.8-37.9) per 100 000 people. After exclusion of an initial 1-year washout period, 13 343 cases of incident keratoconus were identified during the final 5-year period (2010-2014). The incidence rate in the general population was 5.56 cases (95% CI: 5.47-5.66) per 100 000 person-years. Incidence peaked among men in their late 20s and among women in their early 20s. The overall male-to-female incidence rate ratio was 1.00, meaning there was no sex predisposition. Estimates of the nationwide, population-based prevalence and incidence of keratoconus may help deepen our understanding of the pathophysiology of the disease and allow appropriate healthcare system planning.