Peak Indoor NO2 Concentration and Respiratory Outcomes in Children with Asthma

哮喘儿童的室内二氧化氮峰值浓度和呼吸结果

• 批准号: 8393941
• 负责人: LAURA Marie PAULIN
• 金额: $ 5.57万
• 依托单位: JOHNS HOPKINS UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2012
• 资助国家: 美国
• 起止时间: 2012-09-01 至 2014-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8393941
• 关键词: Accident and Emergency department; Affect; African American; Air; Air Pollutants; American; Asthma; Baltimore; Child; Childhood; Childhood Asthma; Chronic Disease; Clinical Data; Coughing; Data Analyses; Disease; Enrollment; Environment; Environmental Monitoring; Equipment; Exposure to; Frequencies; Future; Gases; Goals; Health; Home environment; Hospitalization; Hour; Intervention; Intervention Studies; Investigation; Link; Measurement; Measures; Mentors; Monitor; Morbidity - disease rate; Nitrogen Dioxide; Outcome; Pharmaceutical Preparations; Process; Questionnaires; Relative (related person); Research; Respiratory physiology; Sampling; Source; Speech; Subgroup; Symptoms; System; Time; United States Environmental Protection Agency; Visit; Vulnerable Populations; Work; base; cohort; cost effective; design; diaries; effective intervention; improved; inner city; innovation; interest; member; novel; respiratory

DESCRIPTION (provided by applicant): Asthma is the most common chronic disease among children and current management focuses on control using medications and avoidance of factors that exacerbate the disease. Exposure to outdoor and indoor air pollutants, including nitrogen dioxide (NO2), which is a byproduct of combustion, has been associated with worsening asthma morbidity. Recent evidence suggests that hourly peak concentrations of ambient NO2 are associated with increases in emergency department visits and hospitalizations in people with asthma, prompting the EPA to modify the NAAQS standard for ambient NO2 to include an hourly concentration limit of 100ppb. Investigations by members of this research group have shown an association between higher mean concentrations of indoor NO2 and worsening respiratory symptoms in Baltimore children with asthma. Combustion sources, such as gas stoves, are unique to the indoor environment and produce short-term peak concentrations of NO2 that are not captured in mean concentrations measured over several days. However, the effect of peak indoor NO2 concentrations on asthma health is unknown. We hypothesize that these peak concentrations contribute to worse asthma and are more strongly linked to respiratory health than daily or weekly averages of NO2 concentrations. To study the effect of short-term and peak NO2 concentrations on asthma symptoms and lung function in children with asthma, we propose to add continuous monitoring of indoor NO2 concentrations and the administration of comprehensive time activity diaries in a subgroup (n=40) of children with asthma already enrolled in an existing study, The Center for Childhood Asthma in the Urban Environment ASTHMA-DIET Study. This proposal has three novel aims. First, to determine whether daily peak indoor NO2 concentrations are associated with asthma morbidity in inner city children, we will examine the effect of daily peak indoor NO2 concentrations on lung function and symptoms in children with asthma. Second, to determine whether daily average indoor NO2 concentrations are associated with asthma morbidity in inner city children, we will examine the relationship between 24-hour average NO2 concentrations and asthma outcomes. Finally, we will use detailed time activity diaries to determine the relative contribution of indoo sources to short-term variability in NO2 concentrations in inner-city homes. Results from this study will identify potential sources of elevated NO2 concentrations and inform whether future intervention studies can be directed at short-term increases in NO2 concentrations, which may be more cost-effective and feasible than strategies aimed at continuous NO2 reduction. PUBLIC HEALTH RELEVANCE: Asthma is a common disease of childhood and can be exacerbated by indoor air pollutants, including nitrogen dioxide (NO2), which is produced by combustive processes such as gas stove use. We are interested in quantifying peak and daily concentrations of NO2 in relation to use of combustion sources in the home, and to determine if these concentrations are associated with worsening lung function and symptoms in children with asthma. If peak concentrations of NO2 are found to be the predominant driver of asthma symptoms in children, and these levels are associated with use of an indoor source of NO2, modifying the home environment to reduce exposure during these periods of use may be a feasible intervention to reduce the harmful effect of NO2 on children with asthma.

描述（由申请人提供）：哮喘是儿童中最常见的慢性疾病，目前的治疗重点是使用药物进行控制并避免加剧疾病的因素。接触室外和室内空气污染物，包括燃烧副产品二氧化氮 (NO2)，与哮喘发病率恶化有关。最近的证据表明，环境 NO2 的每小时峰值浓度与哮喘患者急诊就诊和住院次数的增加有关，促使 EPA 修改了环境 NO2 的 NAAQS 标准，将每小时浓度限值纳入 100ppb。该研究小组成员的调查表明，巴尔的摩哮喘儿童的室内二氧化氮平均浓度较高与呼吸道症状恶化之间存在关联。燃气灶等燃烧源是室内环境所特有的，会产生短期的二氧化氮峰值浓度，而几天内测量的平均浓度无法捕获这些峰值浓度。然而，室内二氧化氮峰值浓度对哮喘健康的影响尚不清楚。我们假设这些峰值浓度会导致哮喘恶化，并且与每日或每周平均二氧化氮浓度相比，与呼吸系统健康的关系更为密切。为了研究短期和峰值 NO2 浓度对哮喘儿童哮喘症状和肺功能的影响，我们建议在一个亚组 (n=40) 中添加对室内 NO2 浓度的连续监测和综合时间活动日记的管理患有哮喘的儿童已经参加了一项现有的研究，即城市环境中儿童哮喘中心的 ASTHMA-DIET 研究。 该提案具有三个新颖的目标。首先，为了确定每日室内 NO2 峰值浓度是否与内城区儿童的哮喘发病率相关，我们将检查每日室内 NO2 峰值浓度对哮喘儿童肺功能和症状的影响。其次，为了确定每日平均室内 NO2 浓度是否与市中心儿童的哮喘发病率相关，我们将检查 24 小时平均 NO2 浓度与哮喘结果之间的关系。最后，我们将使用详细的时间活动日记来确定 indoo 源对市中心家庭中 NO2 浓度短期变化的相对贡献。这项研究的结果将确定NO2浓度升高的潜在来源，并告知未来的干预研究是否可以针对NO2浓度的短期升高，这可能比旨在持续减少NO2的策略更具成本效益和可行性。 公共健康相关性：哮喘是儿童的一种常见疾病，室内空气污染物可能会加剧哮喘，其中包括二氧化氮 (NO2)，二氧化氮 (NO2) 是由燃气灶等燃烧过程产生的。我们感兴趣的是量化与家庭燃烧源的使用相关的二氧化氮峰值浓度和每日浓度，并确定这些浓度是否与哮喘儿童肺功能和症状恶化有关。如果发现二氧化氮峰值浓度是儿童哮喘症状的主要驱动因素，并且这些水平与使用室内二氧化氮源有关，那么改变家庭环境以减少这些使用期间的暴露可能是一种可行的干预措施减少NO2对哮喘儿童的有害影响。