The association of urinary polycyclic aromatic hydrocarbon biomarkers and cardiovascular disease in the US population

Abstract

Background: Polycyclic aromatic hydrocarbons (PAHs) are potent atmospheric pollutants produced by incomplete combustion of organic materials. Pre-clinical and occupational studies have reported a positive association of PAHs with oxidative stress, inflammation and subsequent development of atherosclerosis, a major underlying risk factor for cardiovascular disease (CVD). The aim of the current study is to estimate the association between levels of PAH biomarkers and CVD in a national representative sample of United States (US) adults.

Methods: We examined adult participants (≥20years of age) from the merged US National Health and Nutrition Examination Survey 2001-2010. Logistic regression models were used to estimate the associations of each urinary PAH biomarker and CVD. Post-exploratory structural equation modeling was then used to address the interdependent response variables (angina, heart attack, stroke and coronary heart disease) as well as the interdependencies of PAH biomarkers.

Results: PAH biomarkers were positively associated with cardiovascular disease in multiple logistic regression models, although some associations were not statistically robust. Using structural equation modeling, latent PAH exposure variable was positively associated with latent CVD level variable in the multivariable adjusted model (β=0.12; 95% CI: 0.03, 0.20).

Conclusion: A modest association between levels of PAH biomarkers and CVD was detected in US adults. Further prospective studies with adequate sample size are needed to replicate or refute our findings.

Keywords: Cardiovascular disease; NHANES; Polycyclic aromatic hydrocarbons; Structural equation modeling.

Figure 1

Model depicting the hypothesized PAH exposure-CVD association. Data for the National Health and Nutrition Examination Survey 2001–2010 (n=7301) Each latent construct is modeled as a common factor underlying the associated measures. These "loadings" linking constructs to measures are labeled with the Greek character λ "lambda". β "beta" refers to the linear regression parameter regressing the latent CVD variable on the latent PAH exposure variable. Age-sex adjusted unstandardized estimates presented.