Abstract
Purpose :
To investigate the association between building density with myopia among schoolchildren.
Methods :
This multi-center cross-sectional study was conducted in 187 primary schools from four Chinese cities (Shenzhen, Dongguan, Nanjing, and Bayan Nur) and included children from grade 1 to 5. Eye refraction was measured by noncycloplegic autorefraction. Building density in a 500m and 1,000m buffer around schools was quantified using geographic information system technology. Subdistrict-level gross domestic product (GDP) per capita and population density were also collected. Questionnaire was used to estimate parental myopia, screen time, reading time, and outdoor time per day. Generalized linear mixed models were used to investigate the association of building density and individual-level myopia risk, controlling for demographic and questionnaire-derived factors. Multiple linear regression models were used to investigate the association of building density and school-level myopia prevalence.
Results :
A total of 254,195 schoolchildren from four cities were recruited with an average age of 8.2 ± 1.5 years and 55.3% were males. In individual-level analyses adjusted for demographic factors, GDP and population density, a 0.1-unit increase in building density in a 500m and 1000m buffer around schools was associated with a 9.2% (95% confidence interval (CI), 4.7% to 13.9%, P < 0.001) and 10.2% (95% CI, 4.7% to 16.0%, P < 0.001) increase in myopia risk, respectively. After adjusted for demographic, economic and questionnaire-derived factors, a 0.1-increase in building density in a 500m and 1,000m buffer increased myopia risk by 22.4% (95% CI, 10.8% to 35.2%, P < 0.001) and 23.5% (95% CI, 8.0% to 41.2%, P = 0.002), respectively. In school-level analyses, the average myopia rate of 187 included schools was 25.3%. With a 0.1-unit increase in building density in a 500m and 1,000m buffer, school myopia prevalence increased by 1.8% (95% CI, 1.1% to 2.5%, p < 0.001), and 2.2% (95% CI, 1.4% to3.1%, p < 0.001), respectively.
Conclusions :
A higher level of building density around schools is associated with increased myopia risk at individual-level and myopia prevalence at school-level. It suggests a potential novel approach for myopia protection from an urban planning perspective, namely, specifically by implementing regulations on building density.
This abstract was presented at the 2024 ARVO Annual Meeting, held in Seattle, WA, May 5-9, 2024.