Air Pollution, Intima-media Thickness, and Lung Function in College Students

描述（由申请人提供）：本项目追求的假设是，终生累积暴露于环境空气污染与超声测量的18-20岁颈动脉内膜中层厚度（CIMT）相关。CIMT是亚临床动脉粥样硬化-心血管疾病（CVD）的主要致病过程的既定标志物。CIMT从出生到死亡逐渐增加，并且与所有年龄的亚临床炎症相关，并且是CVD的强决定因素。环境空气污染与心血管死亡率和发病率有关，并且是肺部和全身炎症的原因--动脉粥样硬化的标志。空气污染和CIMT之间的显着关联已在成人中报道。长期暴露于空气污染也会对肺功能（LF）产生不利影响，这是CVD死亡率的一个强有力的预测因素。肺部和全身炎症都是低LF的重要相关因素。低LF也会改变污染物在呼吸道中的分布和吸收，导致更高的组织剂量。考虑到影响CIMT、LF和血脂异常、低LF、高C-反应蛋白（CRP）和高血脂（LDL）的全身炎症，这些标志物将用于那些最容易受到空气污染致动脉粥样硬化影响的人。将在800名终生居住在加州的不吸烟南加州大学学生中评估CIMT、终生居住史、心肺协变量、LF、LDL和CRP。全州范围内的空气污染监测信息将被收集起来，以插值每月细颗粒物（PM2.5），二氧化氮（NO2）和臭氧（O3）的浓度，以每个住宅在整个生命周期。浓度将按活动水平和在室内和室外度过的时间加权，以分别得出终生接触的估计值。将使用多变量回归、相互作用检验和结构方程模型研究暴露与CIMT之间的关联以及与LF、CRP和LDL的相互作用。美国心脏协会建议在生命早期关注动脉粥样硬化的预防。空气污染物代表着无处不在的炎症暴露，数百万美国年轻人生活在超过现行政府标准的地区。年轻时CIMT和LF的微小差异转化为临床相关疾病，包括CVD -美国死亡的主要原因。

DESCRIPTION (provided by applicant): This project pursues the hypothesis that lifetime cumulative exposure to ambient air pollution is associated with sonographically measured carotid intima-media thickness (CIMT) at age 18-20. CIMT is an established marker of subclinical atherosclerosis - the primary pathogenic process of cardiovascular diseases (CVD). CIMT gradually increases from birth to death and is associated with subclinical inflammation at all ages, and is a strong determinant of CVD. Ambient air pollution is associated with cardiovascular mortality and morbidity and is a cause of pulmonary and systemic inflammation - a hallmark of atherosclerosis. Significant associations between air pollution and CIMT have been reported in adults. Long-term exposure to air pollution also adversely affects lung function (LF) which is a strong predictor of CVD mortality. Both pulmonary and systemic inflammation is an important correlate of poor LF. Poor LF also modifies the distribution and uptake of pollutants in the respiratory tract, leading to higher tissue dose. Given systemic inflammation affecting CIMT, LF and dyslipidemia, low LF, high C-reactive protein (CRP) and high lipids (LDL) these markers will be used to those most susceptible to atherogenic effects of air pollution. CIMT, lifetime residential history, cardio-respiratory covariates, LF, LDL and CRP will be assessed among 800 non-smoking USC College students with lifetime California residencies. Statewide air pollution monitoring information will be assembled to interpolate monthly fine particulate matter (PM2.5), nitrogen- dioxide (NO2) and ozone (O3) concentrations to each residence across lifetime. Concentrations will be weighted by activity levels and time spent indoors and outdoors to individually derive estimates of lifetime exposure. The association between exposure and CIMT and the interaction with LF, CRP and LDL will be investigated with multivariate regressions, tests for interactions, and structural equation modeling. The American Heart Association recommends focusing on prevention of atherosclerosis in early life. Air pollutants represent ubiquitous inflammatory exposures, and millions of young Americans live in areas that exceed current government standards. Small differences in CIMT and LF at a young age translate into clinically relevant diseases, including CVD - the leading cause of mortality in the U.S.