Association of Built Environment Attributes with Screening Myopia Among Children and Adolescents: Large-Sample, Cross-Sectional, Observational Evidence from Shanghai, China

Background: The built environment might be associated with myopia, but evidences are limited. We explored the relationship between myopia and built environment features, characterized as green spaces, food environment and building density. Methods: We used large-scale, cross-sectional observational data from Shanghai, China. Participants aged 3-20 years old and underwent visual acuity and non-cycloplegic refraction in 2021. Using GIS-based data on environments around participants’ schools and kindergartens, we examined whether green spaces, density of buildings and food shops were associated with myopia. We used logistic mixed effect models adjusting for potential confounders, and conducted several mediate and sensitivity analyses. Findings: Complete case sample sizes were 1727709 from 3399 schools and kindergartens [899817 (52.082%) boys; mean age 10.065 years (SD:3.633)]. Greenness within 1000 m radius of schools was independently associated with lower odds of myopia (OR:0.299, 95%CI:0.249~0.357, P <0.001), with 2.7% of the total effects attributed to the mediation effects of outdoor time. Those exposed in schools with higher building density had significantly higher risk of myopia (OR: 2.764, 95% CI: 2.168~3.525, P <0.001), in which outdoor time accounting for 6.2% of the total effects. Schools with more fast-food outlets nearby was weakly associated with myopia (OR: 1.001, 95% CI:1.001~1.001, P <0.001). No significant effects were observed between ice cream/coffee shops and myopia for the whole population. The effect sizes varied in age and gender, especially higher in 7 to 12-year-old group. Interpretation: This study shows significant effects of greenness, building density and fast-food shops on myopia for 3-20-year-old children and adolescents. Policy makers should consider interventions aimed at tackling the myopic built environment to enhance a eye-health-friendly city or school.Funding: This study was supported by National Key R&D Program of China (No.2021YFC2702100, No.2021YFC2702104, No.2019YFC0840607); Excellent Discipline Leader Cultivation Program of Shanghai Three Year Action Plan on Strengthening Public Health System Construction (No.GWV- 10.2-XD09); National Natural Science Foundation of China (No.82003562); Shanghai Health Commission Research Project (No. 20194Y0308).Declaration of Interest: We declare no competing interests.Ethical Approval: The study protocol was approved by the Institutional Ethics Committee of Shanghai General Hospital and follows the tenets of the Declaration of Helsinki for experimentation on humans. Parents or guardians of all participants were contacted and informed of the study purpose and procedures and informed consent was obtained.