Abstract
Purpose :
During the COVID-19 epidemic, home confinement led to myopic progression in children aged 6-8 years old. A key remaining question is whether the myopia spike persists or returns to pre-pandemic levels. We performed a prospective cross-sectional follow-up study with a cohort sub-study to investigate the changes of refractive status and the prevalence of myopia in school-aged children one year after the home confinement ended.
Methods :
The data for this school-based cohort study were gathered from children in ten primary schools in Feicheng, China. A total of 325,443 children, ranging in age from 6 to 13, were screened eight times over a period of seven years (2015-2021). One screening per year took place from 2015 to 2020, and two screenings took place during the year of 2021. Non-cycloplegic refractive information was obtained using the Spot Vision screening instrument version 2.1.4 (WelchAllyn). The spherical equivalent refraction (SER) was recorded for each child, and the prevalence of myopia was calculated yearly for each age group. This study mainly compares the SER and the prevalence of myopia in 2021 (post home confinement) and 2020 (during home confinement).
Results :
Of the 325,443 children included in the study, 167,152 (51.4%) were boys. Compared with the average SER of school-age children in 2020, the mean SER of children in 2021 increased significantly for ages 6 (+0.42D), 7 (+0.41D) and 8 (+0.33D). The prevalence of myopia (2021 vs. 2019) for each age group was: 6 years old (7.9% vs 5.7%), 7 years old (13.9% vs 13.6%), and 8 years old (29.5% vs 26.2%). Both the prevalence of myopia and mean SER for the school aged children have returned to their pre-epidemic levels.
Conclusions :
Compared with 2020, the prevalence of myopia among children aged 6-8 years in 2021 screenings decreased significantly, and the average SER returned to pre-epidemic level. The refractive development in children aged 6 to 8 is most susceptible to environmental changes. This supports the premise that 6 to 8 years of age is a critical period for myopia development, and suggests focusing preventive interventions for myopia control on children in this age range.
This abstract was presented at the 2023 ARVO Annual Meeting, held in New Orleans, LA, April 23-27, 2023.