Association between Exposure to Ambient Air Pollution and Age-Related Cataract: A Nationwide Population-Based Retrospective Cohort Study

This study aimed to investigate the association between ambient air pollutants and cataracts in the general population aged 50 years or older using data from the Korean National Insurance Service-National Sample Cohort. Cataract patients were defined as those diagnosed by a physician and having undergone cataract surgery. After matching the average concentrations of PM2.5, PM10, NO2, CO, SO2, and O-3 in residential areas, the association between quartile level of air pollutants and incidence of cataract was analyzed using a multivariate Cox-proportional hazard risk model. Among the 115,728 participants, 16,814 (14.5%) were newly diagnosed with cataract and underwent related surgery between 1 January 2004, and 31 December 2015. Exposure to PM10, NO2, and SO2 was positively associated with cataract incidence, while O-3 was negatively associated. The adjusted hazard ratio (HR) with 95% confidence interval was 1.069 (1.025-1.115) in PM10 and 1.080 (1.030-1.133) in NO2. However, the association between cataract and the quartile of PM2.5 measured during one year in 2015 was not clear. The HR of female participants aged 65 or older was significantly increased according to quartile of air pollutants. We identified exposure to PM10, NO2, SO2, and O-3 associated with cataract development in Korean adults aged >= 50 years. This information may be helpful for policymaking to control air pollution as a risk factor for eye health.