Epidemiology and biomarkers of air pollution and burden of coronary artery disease

Abstract

In Lebanon, studies indicated significant increase in the risk factors associated with cardiovascular diseases (CVD). This was manifested by an onset of CVD of 12 years earlier than patients in other parts of the world. Several studies have linked PAH exposure to CVD in general population, and were based on self-reported CVD events related to coronary heart disease (CAD), angina, stroke and heart attack. To our knowledge, this is the first time to examine the association between polycyclic aromatic hydrocarbons (PAH) exposure and CAD based on cardiac catheterization results. Considering the high levels of PAHs in Lebanon due to heavy traffic, abundance of diesel generators in densely populated areas, and poorly maintained power plants in some areas, this study aims at identifying the association between PAH urinary metabolites and CAD based on already available cardiac catheterization results and associated urine samples. The study consists of assessing the CAD burden of a cohort of 258 patients who have been clinically evaluated at the American University of Beirut Medical Center (AUBMC) since 2014. It also includes quantifying hydroxylated polyaromatic hydrocarbons (OHPAH) concentrations in the urine provided by the cardiac cath patients using High Performance Liquid Chromatography coupled with Fluorescence Detector (HPLC-FLD). SPSS software was used to estimate the association between PAH exposure and CVD. PAH urinary metabolites can be considered biomarkers of CVD burden and may be used as a tool for early detection of CVD development. It was determined that OHPAHs concentrations that were measured for non-smokers in this study were higher than the levels that were reported for smokers and some occupational workers which implies that nonsmoker patients are highly exposed to sources of PAH mixtures. Such sources are assigned to old car fleet, diesel generators, incinerators and second hand smoking. In particular, 1-OHPYR showed a significant association with CAD status after adjusting for covariates like ag