Subjective Eye Health Status by Extent of Internet and Smartphone Use by Korean Adolescents

Purpose: To explore the subjective eye health status of Korean adolescents by the extent of Internet use in 2009-2010 and smartphone use in 2020.Methods: We secondarily analyzed the results of the Korea Youth Risk Behavior Survey performed by the Korean Disease Control and Prevention Agency that enrolled Korean adolescents aged 12-18 years. Changes in internet use time from 2009 to 2019 and smartphone use in 2020 were examined. Questionnaires exploring subjective eye health were administered in 2009, 2010, and 2020. We performed complex logistic regression analysis.Results: A total of 748,490 subjects were enrolled. Korean adolescents used the Internet for an average of 2.48 hours (h) on weekdays and 4.06 h on weekends in 2019, thus significantly more than the 2009 averages of 1.93 h on weekdays and 2.96 h on weekends (both p < 0.001). In 2009 and 2010, the average internet use time on weekends significantly and positively correlated with subjective eye problems (odds ratio = 1.161, p < 0.001). The average smartphone use time was 4.72 h on weekdays and 6.56 h on weekends in 2020. In that year, the average smartphone use time on weekends (odds ratio = 1.049, p < 0.001) and smartphone overdependence (odds ratio = 8.636, p < 0.001) significantly and positively correlated with the presence of subjective health problems.Conclusions: Internet and smartphone use time on weekends affect subjective eye health.