Green Space Morphology and School Myopia in China

Yahan Yang, Huipeng Liao, Lanqin Zhao, Xun Wang, XiaoWei Yang, Xiaohu Ding, Xuelong Li, Zhiyu Jiang, Xingying Zhang, Qingling Zhang, Huagui He, Liang Guo, Hualiang Lin, Guanghui Dong, Bryan Spencer, Mingguang He, Nathan Congdon, Ian George Morgan, Haotian Lin

Research output: Journal article publicationJournal articleAcademic researchpeer-review

1 Citation (Scopus)

Abstract

Importance: China has experienced both rapid urbanization and major increases in myopia prevalence. Previous studies suggest that green space exposure reduces the risk of myopia, but the association between myopia risk and specific geometry and distribution characteristics of green space has yet to be explored. These must be understood to craft effective interventions to reduce myopia.

Objective: To evaluate the associations between myopia and specific green space morphology using novel quantitative data from high-resolution satellite imaging.

Design, setting, and participants: This prospective cohort study included students grades 1 to 4 (aged 6 to 9 years) in Shenzhen, China. Baseline data were collected in 2016-2017, and students were followed up in 2018-2019. Data were analyzed from September 2020 to January 2022. 

Exposures: Eight landscape metrics were calculated using land cover data from high-resolution Gaofen-2 satellite images to measure area, aggregation, and shape of green space. 

Main outcome and measures: The 2-year cumulative change in myopia prevalence at each school and incidence of myopia at the student level after 2 years were calculated as main outcomes. The associations between landscape metrics and school myopia were assessed, controlling for geographical, demographic, and socioeconomic factors. Principal component analyses were performed to further assess the joint effect of landscape metrics at the school and individual level. 

Results: A total of 138 735 students were assessed at baseline. Higher proportion, aggregation, and better connectivity of green space were correlated with slower increases in myopia prevalence. In the principal component regression, a 1-unit increase in the myopia-related green space morphology index (the first principal component) was negatively associated with a 1.7% (95% CI, −2.7 to −0.6) decrease in myopia prevalence change at the school level (P = .002). At the individual level, a 1-unit increase in myopia-related green space morphology index was associated with a 9.8% (95% CI, 4.1 to 15.1) reduction in the risk of incident myopia (P < .001), and the association remained after further adjustment for outdoor time, screen time, reading time, and parental myopia (adjusted odds ratio, 0.88; 95% CI, 0.80 to 0.97; P = .009).

Conclusion and relevance:  Structure of green space was associated with a decreased relative risk of myopia, which may provide guidance for construction and renovation of schools. Since risk estimates only indicate correlations rather than causation, further interventional studies are needed to assess the effect on school myopia of urban planning and environmental designs, especially size and aggregation metrics of green space, on school myopia.

Original languageEnglish
Pages (from-to)115-122
Number of pages8
JournalJAMA Ophthalmology
Volume142
Issue number2
DOIs
Publication statusPublished - 18 Feb 2024

ASJC Scopus subject areas

  • Ophthalmology

Fingerprint

Dive into the research topics of 'Green Space Morphology and School Myopia in China'. Together they form a unique fingerprint.

Cite this