Is long-term PM exposure associated with blood lipids and dyslipidemias in a Chinese rural population?

Background: Air pollution has been shown to be associated with blood lipid levels. However, studies on long-term ambient particulate matter with aerodynamic diameter ≤1 μm (PM) exposure in high-exposure areas are still limited. This study aimed to explore the associations among long-term PM exposure, blood lipids and dyslipidemias.

Methods: Baseline data of The Henan Rural Cohort study was used in present study, including a total of 39,259 participants aged from 18 to 79 years. Daily levels of PM were estimated by a spatiotemporal model using ground-level measurements of PM, satellite remote sensing data and other predictors, according to participants' home addresses. Individual exposure to PM was the 3-year average before baseline investigation. Linear regression and logistic regression models were applied to examine the associations among PM, blood lipids ((total cholesterol (TC), triglyceride (TG), high-density lipoprotein cholesterol (HDL-C) and low-density lipoprotein cholesterol (LDL-C)), and prevalence of dyslipidemias.

Results: The 3-year concentration of PM was 55.7 ± 2.1 μg/m. Each 1 μg/m increment of PM was associated with an increase of 0.21% (95% confidence interval (CI): 0.11%-0.31%) in TC and 0.75% (95% CI: 0.61%-0.90%) in LDL-C, while decrease of 2.68% (95% CI: 2.43%-2.93%) in TG and 0.47% (95% CI: 0.35%-0.59%) in HDL-C. Each 1 μg/m increase in PM was associated with 6% (95% CI: 4%-8%), 3% (95% CI: 2%-5%) and 5% (95% CI: 3%-7%) higher risks of hypercholesterolemia, hyperbetalipoproteinemia and hypoalphalipoproteinemia. Sex, age and BMI statistically modified the associations between PM with blood lipid levels and dyslipidemias.

Conclusions: Higher PM exposure was associated with adverse changes of blood lipid levels and dyslipidemias. Males, older and overweight participants were susceptive to the adverse effects of PM.