Abstract
Purpose :
To investigate the prevalence and temporal trend of myopia throughout a 25-year period in urban and rural children and adolescents in China
Methods :
Data of 7.5 million children and adolescents (aged 7 to 18) from 187 individual school-based studies from 1998 to 2022 were analyzed, covering 31 provinces or autonomous regions around China. A weighted prevalence of myopia was estimated in both urban and rural regions at Grade 1-3 (or 7-9 years), Grade 4-6 (or 10-12 years), Grade 7-9 (or 13-15 years), and Grade 10-12 (or 16-18 years), respectively. The temporal change of myopia was analyzed in 6 time periods, including before and after the Covid-19 pandemic.
Results :
Prevalence of myopia in varied age groups was calculated in urban and rural regions, from 1998 to 2022 (Tab 1, Fig 1). The prevalence increased sharply in rural areas. For every 5 years, a rise was observed by 5%, 11%, 14% and 17% in Grade 1-3, Grade 4-6, Grade 7-9, and Grade 10-12, respectively. The change was steady in each age group in urban areas, with an increase by 5% to 7%, for every 5 years. The urban-rural gap reduced significantly over time for each age group (P<0.001), and achieved a similar prevalence (urban rural ratio ≤1.1) for children at Grade 1-3 since 2008-2011, and for children Grade 4-12 since 2012-2015 (Fig 2). The pandemic (2020-2022) saw a rise in myopia, with an increase by 15% for children at Grade 1-3, by 17% at Grade 4-6, and by 6% at Grade 7-9 (all P<0.001). However, myopia was not more prevalent in pandemic for adolescents at Grade 10-12(P=0.786) (Fig 1).
Conclusions :
We reported the prevalence of myopia in Chinese children and adolescents from 1998 to 2022 based on data of 7.5 million participants. Although an uprising trend was observed in all groups, the prevalence in rural children rose sharply and the rural-urban difference had been minor after 2015. The pandemic-related myopia increase was significant in children, but not in adolescents in senior high school.
This abstract was presented at the 2023 ARVO Annual Meeting, held in New Orleans, LA, April 23-27, 2023.