Investigation of Neighborhood Greenspace as Protection Against Development of Childhood Asthma

项目总结/摘要 新出现的证据表明，暴露于植被覆盖的土地，或“绿地”，特别是在生命早期， 可以预防哮喘的发展。这种关系背后的一种拟议机制描述了微生物 自然景观的多样性有助于附近儿童的微生物组特征， 支持强大的免疫发育。另一个被提出的机制涉及到清除引起哮喘的空气 污染物的树冠。我们提出了一个研究邻里绿地与哮喘的关系 发病率，在一个纵向队列超过170,000名儿童生活在费城大都市区， 从婴儿期开始。在拟议的研究中，我们将把电子健康记录（EHR）与定义的 高空间分辨率绿地指标，由儿童的个人地理编码的地址。我们丰富 数据库还将包括一系列其他环境和社会人口措施， 儿童居住的社区，需要从其他绿色空间中分离出绿色空间的个体效应， 邻里因素，也使一个有意义的分析的共同影响，绿地与其他 可能增加或减少潜在绿地效益的条件。在我们的研究中，我们的具体目标是： 1)从婴儿期到2010年，研究社区绿地与哮喘发病率之间的关系。 城市和郊区儿童队列中的儿童期（特别是2岁、7岁和12岁）; 2）评估修改 绿地和哮喘发病率之间的关系，通过其他社区特征， 改变风险或脆弱性，包括空气污染（PM2.5、O3）、交通、城市状况和社会人口统计; 3)描述哮喘表型与邻里绿地相关性的异质性。我们 将评估与哮喘发病率有关的几项绿地措施，包括整体绿化，树木 树冠覆盖率、草/灌木、自然土地覆盖多样性和绿色空间的空间属性（例如，贴片 大小、聚集），并且我们将研究这些作为时间窗口特定的度量（例如，婴儿期）和 随访期间累积的绿地暴露。我们的研究将提供一个强大的分析的潜力， 城市绿地暴露在生命早期，以防止哮喘的发展。此外，来自 亚组和表型分析可以提供有关绿地可能 影响哮喘的风险，以及潜在影响的范围。

PROJECT SUMMARY/ABSTRACT Emerging evidence suggests that exposure to vegetated land cover, or ‘greenspace’, particularly in early life, may prevent development of asthma. One proposed mechanism behind this relationship describes microbial diversity of natural landscapes contributing to diverse microbiome profiles in children who live nearby, thus supporting robust immune development. Another proposed mechanism involves removal of asthma-causing air pollutants by tree canopy. We propose a study of neighborhood greenspace in relation to the asthma incidence, in a longitudinal cohort of over 170,000 children living in the Philadelphia metropolitan region, followed from infancy. In the proposed study, we will link electronic health records (EHR) from the defined cohort to high-spatial resolution greenspace metrics, by children’s individual geocoded addresses. Our rich database will also include an array of additional environmental and sociodemographic measures of the neighborhoods where children live, needed to disentangle the individual effects of greenspace from other neighborhood factors, and also enabling a meaningful analysis of the joint effects of greenspace with other conditions that may enhance or diminish the potential greenspace benefits. In our study, we specifically aim to: 1) Investigate the association between neighborhood greenspace and asthma incidence from infancy through childhood (specifically, ages 2, 7 and 12) in a cohort of urban and suburban children; 2) Evaluate modification of the relationship between greenspace and asthma incidence by other neighborhood characteristics that may alter risk or vulnerability, including air pollution (PM2.5, O3), traffic, urban status, and sociodemographics; and, 3) Describe heterogeneity of the association with neighborhood greenspace among asthma phenotypes. We will evaluate several greenspace measures in relation to asthma incidence, including overall greenness, tree canopy coverage, grass/shrubs, natural landcover diversity, and spatial attributes of green spaces (e.g., patch size, aggregation), and we will investigate these measures as time-window specific (e.g., infancy) and cumulative greenspace exposures during follow-up. Our study will provide a robust analysis of the potential for urban greenspace exposure in early life to protect against development of asthma. In addition, information from subgroup and phenotype analyses may provide clues regarding the mechanisms by which greenspace may affect risk of asthma, as well as the scope of potential impact.