Prevalence and related factors of children myopia in Pudong New Area, Shanghai: a cross-sectional study.

Objectives: This study aimed to assess the prevalence and related factors of myopia among school-aged children after COVID-19 pandemic.

Design: Cross-sectional study.

Setting: Pudong New Area, Shanghai.

Participants: 1722 children aged 7-9 randomly selected from 8 primary schools were screened from 1 February 2023 to 30 April 2023.

Main Outcome Measures: Children's height, weight and eye parameters were examined. Myopia was defined as a cycloplegic spherical equivalent ≤-0.50 dioptres in either eye. A vision-related behaviour questionnaire was applied to investigate the associations between myopia and its risk factors.

Results: Of the 1722 individuals enrolled, 25.6% (456) had myopia. After adjusting other characteristics, the following factors were associated with an increased rate of myopia: age (9 years vs 7 years, adjusted OR (AOR) 1.84, 95% CI 1.18 to 2.85, p=0.007), parental myopia status (both myopia vs none, AOR 5.66, 95% CI 3.71 to 8.63, p<0.001; one myopia vs none, AOR 2.92, 95% CI 1.93 to 4.42, p<0.001), reading books too close (yes vs no, AOR 1.58, 95% CI 1.20 to 2.08, p=0.001), writing with a tilted head (yes vs no, AOR 1.37, 95% CI 1.05 to 1.77, p=0.019), sleep patterns (early to bed late to rise vs early to bed early to rise, AOR 1.52, 95% CI 1.02 to 2.26, p=0.039). By contrast, a higher monthly household income and the habit of reading while lying down were associated with lower risk of myopia.

Conclusions: The prevalence of myopia is of concern among young school-aged children after COVID-19. Correcting eye use behaviour and improving sleep habits may reduce myopia. Also, gender differences should be considered in prevention strategies for children's myopia.