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，终身累积暴露于环境空气污染与18-20岁时超声测量的颈动脉内膜-中膜厚度（CIMT）有关。CIMT是确定的亚临床动脉粥样硬化-心血管疾病（CVD）的主要致病过程的标志物。CIMT从出生到死亡逐渐增加，并与所有年龄段的亚临床炎症相关，是CVD的一个强有力的决定因素。环境空气污染与心血管疾病的死亡率和发病率有关，是引起肺部和全身炎症的原因——这是动脉粥样硬化的一个标志。据报道，空气污染与成人CIMT之间存在显著关联。长期暴露于空气污染也会对肺功能（LF）产生不利影响，而肺功能是心血管疾病死亡率的一个强有力的预测指标。肺部和全身炎症都是LF不良的重要相关因素。低LF也改变了污染物在呼吸道的分布和吸收，导致较高的组织剂量。考虑到影响CIMT、LF和血脂异常的全身性炎症，低LF、高c反应蛋白（CRP）和高血脂（LDL），这些标志物将用于最容易受到空气污染致动脉粥样硬化影响的人群。将对800名在加州终身居住的南加州大学非吸烟学生进行CIMT、终身居住史、心肺协变量、LF、LDL和CRP的评估。全州范围的空气污染监测信息将被收集起来，以插值每个居民一生中每月的细颗粒物（PM2.5）、二氧化氮（NO2）和臭氧（O3）浓度。浓度将按活动水平和在室内和室外度过的时间加权，以单独得出终生暴露的估计。暴露与CIMT之间的关系以及与LF、CRP和LDL的相互作用将通过多变量回归、相互作用测试和结构方程模型进行研究。美国心脏协会建议关注早期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，数百万年轻的美国人生活在超过当前政府标准的地区。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.