Jarvis Ingrid, Davis Zoë, Sbihi Hind, Brauer Michael, Czekajlo Agatha, Davies Hugh W, Gergel Sarah E, Guhn Martin, Jerrett Michael, Koehoorn Mieke, Oberlander Tim F, Su Jason, van den Bosch Matilda
Department of Forest and Conservation Sciences, Faculty of Medicine, University of British Columbia, Vancouver, BC, Canada.
School of Population and Public Health, Faculty of Medicine, University of British Columbia, Vancouver, BC, Canada; British Columbia Centre for Disease Control, Vancouver, BC, Canada.
Lancet Planet Health. 2021 Oct;5(10):e709-e717. doi: 10.1016/S2542-5196(21)00235-7.
Exposure to greenspace is associated with improved childhood development, but the pathways behind this relationship are insufficiently understood. Therefore, we aimed to investigate the association between lifetime residential exposure to greenspace and early childhood development and evaluate the extent to which this association is mediated by reductions in traffic-related air pollution and noise.
This population-based birth cohort study comprised singleton births in Metro Vancouver, BC, Canada, between April 1, 2000, and Dec 31, 2005. Children and mothers had to be registered with the mandatory provincial health insurance programme, Medical Services Plan, and have lived within the study area from the child's birth to the time of outcome assessment. Early childhood development was assessed via teacher ratings on the Early Development Instrument (EDI), and we used the total EDI score as the primary outcome variable. We estimated greenspace using percentage vegetation derived from spectral unmixing of annual Landsat satellite image composites. Lifetime residential exposure to greenspace was estimated as the mean of annual percentage vegetation values within 250 m of participants' residential postal codes. Multilevel modelling, adjusted for eight covariates, was used to investigate associations between greenspace exposure and EDI scores. We estimated the mediation effects of nitrogen dioxide (NO), fine particulate matter (PM), and noise levels using causal mediation analyses.
Of the 37 745 children born in Metro Vancouver between April 1, 2000, and Dec 31, 2005, 27 372 were included in our final study sample. In the adjusted model, 1 IQR increase in percentage vegetation was associated with a 0·16 (95% CI 0·04-0·28; p=0·0073) increase in total EDI score, indicating small improvements in early childhood development. We estimated that 97·1% (95% CI 43·0-396·0), 29·5% (12·0-117·0), and 35·2% (17·9-139·0) of the association was mediated through reductions in NO, PM, and noise, respectively.
Increased exposure to residential greenspace might improve childhood development by reducing the adverse developmental effects of traffic-related exposures, especially NO air pollution. Our study supports the implementation of healthy urban planning and green infrastructure interventions.
Canadian Institutes of Health Research.
接触绿地与儿童发育改善相关，但这种关系背后的途径尚不清楚。因此，我们旨在研究一生中居住环境接触绿地与幼儿发育之间的关联，并评估这种关联在多大程度上是由与交通相关的空气污染和噪音减少所介导的。
这项基于人群的出生队列研究包括2000年4月1日至2005年12月31日在加拿大不列颠哥伦比亚省大温哥华地区的单胎出生。儿童和母亲必须注册参加强制性的省级医疗保险计划“医疗服务计划”，并且从孩子出生到结果评估时一直居住在研究区域内。通过教师对早期发展工具（EDI）的评分来评估幼儿发育情况，我们将EDI总分作为主要结局变量。我们使用从年度陆地卫星图像合成光谱解混得到的植被百分比来估算绿地面积。一生中居住环境接触绿地的情况被估算为参与者居住邮政编码250米范围内年度植被百分比值的平均值。采用多水平模型，并对八个协变量进行了调整，以研究绿地接触与EDI评分之间的关联。我们使用因果中介分析来估算二氧化氮（NO）、细颗粒物（PM）和噪音水平的中介效应。
在2000年4月1日至2005年12月31日于大温哥华地区出生的37745名儿童中，27372名被纳入我们的最终研究样本。在调整后的模型中，植被百分比每增加1个四分位间距，EDI总分增加0.16（95%CI 0.04 - 0.28；p = 0.0073），表明幼儿发育有小幅改善。我们估计，分别有97.1%（95%CI 43.0 - 396.0）、29.5%（12.0 - 117.0）和35.2%（17.9 - 139.0）的关联是通过减少NO、PM和噪音介导的。
增加居住环境接触绿地可能通过减少与交通相关暴露的不良发育影响，尤其是NO空气污染，来改善儿童发育。我们的研究支持实施健康的城市规划和绿色基础设施干预措施。
加拿大卫生研究院。
