Acute Effects of Diesel Exhaust in Asthmatic Children

柴油机尾气对哮喘儿童的急性影响

• 批准号: 7100123
• 负责人: TOBY C LEWIS
• 金额: $ 12.88万
• 依托单位: UNIVERSITY OF MICHIGAN AT ANN ARBOR
• 依托单位国家: 美国
• 财政年份: 2004
• 资助国家: 美国
• 起止时间: 2004-09-06 至 2009-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7100123
• 关键词: aerosols; airborne allergen; asthma; carbon; clinical research; clinical trials; engine exhaust; environmental contamination; environmental exposure; enzyme linked immunosorbent assay; human subject; hydrogen peroxide; interview; middle childhood (6-11); petroleum oil; respiratory airflow disorder; respiratory disorder diagnosis; respiratory function; respiratory hypersensitivity; spirometry; urban area

DESCRIPTION (provided by applicant): Exposure to diesel exhaust, a significant source of particulate matter (PM) in urban residential environments, adversely effects respiratory health of asthmatics and augments allergic sensitization to allergens. Yet much remains unknown about which aspects of diesel exposure are driving the observed health effects, the effect of diesel exhaust exposure in combination with other asthma triggers, and whether any of the effects of diesel are modifiable on an individual basis. The Michigan Center for the Environment and Children's Health (MCECH) recently conducted an integrated ambient PM exposure assessment, health effects epidemiologic study, and home intervention to reduce indoor allergens among asthmatic children in Detroit. Fluctuations in lung function associated with PM2.5 or PM10 exposure were more prominent in children who were allergic to cockroach compared to those who were not allergic. These data suggest a model in which PM, specifically that derived from diesel exhaust, and indoor allergen exposures interact synergistically to increase pulmonary inflammation in asthmatic patients. To test this hypothesis, the investigators propose these specific aims: 1) Determine whether the fraction of ambient PM arising from diesel exhaust determines pollution-related respiratory health effects in children with asthma in an inner-city environment. Statistical associations between ambient elemental carbon (EC), a marker for diesel exhaust, and acute respiratory outcomes (lung function, symptoms, bronchodilator use, acute care visits) will be investigated in children with asthma. 2) Determine the potential interactions between the effects of ambient diesel exhaust (as traced by EC) and exposure to allergens and environmental tobacco smoke (lETS). Interactive effects between EC and household exposure to indoor allergens, and ETS exposure, on health status will be investigated in children with asthma. 3) Determine the causal relationship between indoor allergen exposure and heightened sensitivity to air pollutants by performing an intervention designed to reduce indoor allergen exposure. A new integrated health effects study and prospective randomized trial of home environmental intervention will be conducted with extensive spatial and temporal assessment of ambient diesel exposure, assessed by EC concentration and ultrafine particle number, and health outcomes. The investigators will compare the acute air pollutant-associated fluctuations in asthma health status in the intervention group to that in a control group. They will also investigate associations between exhaled hydrogen a biomarker of asthma activity, and diesel exhaust exposure.

描述（由申请人提供）： 柴油机尾气是城市居住环境中颗粒物 (PM) 的重要来源，接触柴油机尾气会对哮喘患者的呼吸系统健康产生不利影响，并增加对过敏原的过敏反应。 然而，对于柴油暴露的哪些方面正在驱动所观察到的健康影响、柴油尾气暴露与其他哮喘诱因相结合的影响，以及柴油的任何影响是否可以根据个人情况进行改变，仍然有很多未知之处。密歇根环境与儿童健康中心 (MCECH) 最近进行了一项综合环境 PM 暴露评估、健康影响流行病学研究和家庭干预，以减少底特律哮喘儿童的室内过敏原。与不过敏的儿童相比，对蟑螂过敏的儿童与 PM2.5 或 PM10 暴露相关的肺功能波动更为明显。这些数据提出了一个模型，其中颗粒物（特别是来自柴油机尾气的颗粒物）和室内过敏原暴露协同相互作用，增加哮喘患者的肺部炎症。为了检验这一假设，研究人员提出了以下具体目标： 1) 确定柴油机尾气产生的环境 PM 比例是否决定了城市内环境中患有哮喘的儿童与污染相关的呼吸系统健康影响。将在患有哮喘的儿童中研究环境元素碳（EC）（柴油机尾气的标志物）与急性呼吸系统结果（肺功能、症状、支气管扩张剂的使用、紧急护理就诊）之间的统计关联。 2) 确定环境柴油废气（通过 EC 追踪）的影响与暴露于过敏原和环境烟草烟雾 (IETS) 之间的潜在相互作用。将在患有哮喘的儿童中研究 EC 和家庭暴露于室内过敏原以及 ETS 暴露对健康状况的交互影响。 3) 通过执行旨在减少室内过敏原暴露的干预措施，确定室内过敏原暴露与对空气污染物敏感性升高之间的因果关系。一项新的综合健康影响研究和家庭环境干预的前瞻性随机试验将通过对环境柴油暴露进行广泛的空间和时间评估，通过 EC 浓度和超细颗粒数量以及健康结果进行评估。 研究人员将干预组与对照组中与急性空气污染物相关的哮喘健康状况波动进行比较。 他们还将研究呼出的氢气（哮喘活动的生物标志物）与柴油机尾气暴露之间的关联。