Investigation of Neighborhood Greenspace as Protection Against Development of Childhood Asthma

项目摘要/摘要 新出现的证据表明，接触植被覆盖的土地，或绿地，特别是在生命的早期， 可以预防哮喘的发展。一种提出的这种关系背后的机制描述了微生物 自然景观的多样性导致了居住在附近的儿童的微生物群谱不同，因此 支持强健的免疫发展。另一种拟议的机制涉及清除导致哮喘的空气 树木树冠造成的污染物。我们建议对社区绿地与哮喘的关系进行研究。 在生活在费城大都市区的17万多名儿童的纵向队列中， 从婴儿时期就开始了。在拟议的研究中，我们将把电子健康记录(EHR)与定义的 根据儿童单独的地理编码地址，对高空间分辨率的绿地指标进行队列。我们的富人 数据库还将包括一系列额外的环境和社会人口统计指标 儿童居住的社区需要将绿地的个人影响与其他社区分开 社区因素，并使有意义的分析绿地的联合影响与其他 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)调查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童年(特别是2、7和12岁)；2)评估修改 绿地与哮喘发病率之间的关系可能与其他社区特征有关 改变风险或脆弱性，包括空气污染(PM2.5、臭氧)、交通、城市状况和社会人口结构；以及 3)描述哮喘表型与邻里绿地关系的异质性。我们 将评估与哮喘发病率相关的几项绿地措施，包括总体绿色度、树木 树冠覆盖度、草/灌木、自然土地覆盖多样性和绿地的空间属性(例如，斑块 大小、聚合)，我们将按特定时间窗口(例如，婴儿期)和 随访期间的累积绿地暴露。我们的研究将提供一个强有力的分析潜在的 城市绿地早年暴露，预防发展哮喘。此外，来自 亚群和表型分析可以提供关于绿地可能 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.