Association between Air Pollution Exposure and Epigenetic Age Acceleration: Insights from the Taiwan Biobank

Abstract

Exposure to air pollution has been associated with various health outcomes, but its impact on epigenetic age acceleration (EAA) remains inconclusive. The study aims to assess the relationship between air pollution exposure and EAA in a Taiwanese cohort. The Taiwan Biobank (TWB) has been recruiting community-based adults aged 30 to 70 years since 2012, with a total of 173,806 participants enrolled by the end of 2022. Among them, 2,469 were selected for serum DNA methylation (DNAm) analysis. DNAm ages were estimated through penalized elastic net regression, and residuals were qualified as TWBEAA. Additionally, four EAAs were calculated using Horvath’s online DNA Methylation Age Calculator: DNAmEAA, DNAmSkinBloodEAA, PhenoEAA, and GrimEAA. Air pollution exposure levels at participants' residential townships were estimated from pre-1 day through pre-1 year using a kriging-based spatial interpolation method. Associations were assessed using multiple linear regression models. The TWB epigenetic age-predicting model contained 179 CpG sites with an R-Squared of 0.94, higher than those by DNAmEAA and DNAmSkinBloodEAA. In the single-pollutant model, we observed significant positive associations between long-term exposure to PM2.5 (β = 0.39 [0.22–0.56]), SO2 (β = 0.14 [0.05–0.23]), O3 (β = 0.15 [0.03–0.27]), and TWBEAA. In the two-pollutant model, only PM2.5 remained robust, while other pollutants did not exhibit consistent associations. Similar adverse effects of air pollution exposure were observed for DNAmEAA and DNAmSkinBloodEAA. This study represents one of the first attempts to quantify epigenetic clocks using an Asian population-based predicting model. The findings suggest that exposure to air pollution may accelerate epigenetic aging, particularly to PM2.5.

Note:
Funding Information: The study was supported by the Health Promotion Administration, Ministry of Health and Welfare, Taiwan (Grant No. 112-0324-02-30-01).

Conflict of Interests: Yue Leon Guo reports financial support was provided by Health Promotion Administration, Ministry of Health and Welfare, Taiwan. If there are other authors, they declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.

Ethical Approval: The study protocol was approved by the Institutional Review Board of National Taiwan University Hospital (202210076RINB).

Keywords: Taiwan Biobank, air pollution, epigenetic age, DNA methylation