Association between air pollution and telomere length: A study of 471,808 UK Biobank participants

Previous research suggested an association between air pollution and shortened telomere length (TL), a biomarker of oxidative stress and inflammation. However, supporting results are challenged by the small sample size and heterogeneity in participant characteristics. To comprehensively evaluate the association of long-term exposure to air pollution with telomere length, we studied 471,808 participants from UK Biobank with measurements on leukocyte telomere length (LTL). Air pollution data on PM2.5, PM10, NO2, NOx, SO2, and CO before baseline at 1 km spatial resolution were collected and linked to each participant��s residential address. We applied mixed-effects linear regression models to examine the association between long-term air pollution exposure and LTL. Compared to the lowest quartile (Q1) of air pollutants, the estimated percentage changes of age-corrected LTL were -2.71% [95% confidence interval (CI): -3.78, -1.63] for SO2, -0.82% (95% CI: -1.87, 0.23) for NO2, -1.17% (95% CI: -2.23, -0.11) for NOx, and -0.47% (95% CI: -1.45, 0.53) for CO in the highest quartile groups (Q4). Decreasing trends in age-corrected LTL following the increase in PM2.5 and PM10 leveled off during high levels of air pollutants. Among participants with lower household income, lower educational attainment, and higher BMI, a stronger association was found between air pollution and LTL. Our findings suggest a negative association between air pollution and LTL and provide insights into the potential pathways linking air pollution to age-related diseases.