Long-term Air Pollution Exposure and Mortality in the NIH-AARP Cohort

描述（由申请人提供）：我们已经取得了重要的发现，室外PM2.5（空气动力学直径小于2.5 um的颗粒的质量浓度）与全因和主要心血管疾病（CVD）死亡率有关，包括缺血性心脏病（IHD），并可能与肺癌有关。然而，环境空气中的PM2.5是一个复杂的混合物，其来源和化学成分差异很大。因此，PM2.5风险的程度以及PM2.5污染的哪些来源和/或成分是造成这些影响的主要原因，仍然存在很大的不确定性。此外，人们怀疑吸烟、体重指数和其他因素可能会改变长期的空气污染死亡风险，但这些潜在的改变作用及其对识别潜在易感人群的影响尚未得到很好的理解。我们建议使用美国国立卫生研究院-美国退休人员协会的“饮食与健康研究”来解决这些研究需求，这是一项超过50万人的队列研究，他们分别以疾病风险因素为特征，并在1995-96年至2008年期间对特定疾病的死亡率进行了跟踪，在前10年的随访中，已经确定了6万多人死亡（19,400人死于心血管疾病，11,500人死于IHD， 7600多人死于肺癌）。除了在美国引入一个主要的新的空气污染研究队列外，我们的研究还将进行创新的暴露评估，将详细的NIH-AARP队列居住数据与空气污染数据联系起来。这些数据将包括来自EPA空气质量系统（AQS）网络数据的PM2.5质量和气态共污染物数据，以及来自EPA全国化学形态网络（CSN）的PM2.5成分数据。在另一项重大进展中，美国国立卫生研究院-美国退休人员协会的受试者流动性数据将允许对那些搬家的人进行时间依赖的暴露分类。有了这些进展，我们的研究团队建议在NIH-AARP队列中进行流行病学分析，这将：1)更准确地量化长期PM2.5空气污染与死亡率之间的关联；2)确定与总死亡率和死因特异性死亡率最密切相关的PM2.5源类别和微量成分；3)确定风险最大的人群亚群。美国环境保护署估计，在美国，长期暴露于PM2.5与约73,000例缺血性心脏病（IHD）死亡有关（美国环境保护署，2010年），与每年因吸烟导致的85,000例缺血性心脏病死亡人数相同（疾病预防控制中心，2005年）。这项研究将独特地确定空气污染源类别和PM2.5成分与全因、心血管疾病和IHD死亡率最密切相关，这是为空气污染预防政策提供信息的一个至关重要的进展。这项研究还将确定易感人群亚组，从而为医生提供关键的临床信息，以便就空气污染对健康的影响和预防向患者提供建议。

DESCRIPTION (provided by applicant): We have made significant findings that outdoor PM2.5 (the mass concentration of particles less than 2.5 um in aerodynamic diameters) is related to all-causes and major cardiovascular disease (CVD) mortality, including ischemic heart disease (IHD), and possibly to lung cancer. However, PM2.5 in ambient air is a complex mixture that varies greatly in sources and chemical constituents. As a result, significant uncertainty remains as to the magnitude of the PM2.5 risk and which sources and/or constituents of PM2.5 pollution are most responsible for these effects. Also, it is suspected that smoking, BMI, and other factors may modify long-term air pollution-mortality risks, but these potential modifying effects and their implications for identifying potentially susceptible populations are not well understood. We propose studies to address these research needs using the NIH-AARP "Diet and Health Study", a cohort of over one-half million people characterized individually for disease risk factors and followed for disease-specific mortality from 1995-96 to 2008, with over 60,000 deaths already ascertained in the first 10 years of follow-up (19,400 attributed to CVD, 11,500 to IHD, and over 7,600 to lung cancer). In addition to introducing a major new cohort in the U.S. for air pollution research, our study will carry out innovative exposure assessment, linking the detailed NIH-AARP cohort residence data to air pollution data. These data will include PM2.5 mass and gaseous co-pollutant data from the EPA's Air Quality System (AQS) network data, and PM2.5 constituent data from the EPA's nationwide Chemical Speciation Network (CSN). In another significant advance, the NIH-AARP subject mobility data will allow time-dependent exposure classification for those who move residence. With these advances, our research team propose epidemiologic analyses in the NIH-AARP cohort that will: 1) more accurately quantify associations between long-term PM2.5 air pollution and mortality; 2) identify the PM2.5 source categories and trace constituents most closely associated with total and cause-specific mortality; and, 3) identify the population subgroups at greatest risk. The U.S. EPA estimates that long-term exposure to PM2.5 in the US is associated with some 73,000 ischemic heart disease (IHD) deaths (U.S. EPA, 2010), which is on the same scale as the 85,000 IHD deaths per year caused by smoking (CDC, 2005). This study will uniquely identify air pollution source categories and PM2.5 constituents most strongly associated with all-cause, CVD and IHD mortality, a critically important advance for informing air pollution prevention policy. The study will also identify susceptible population sub-groups, and thereby provide physicians with critical clinical information for advising patients about air pollution health effects and prevention.