BACKGROUND: Short-duration exposure to ambient particulate matter (PM) air pollution is associated with cardiac autonomic dysfunction and prolonged ventricular repolarization. However, associations with sub-chronic exposures to coarser particulates are relatively poorly characterized as are molecular mechanisms underlying their potential relationships with cardiovascular disease.
MATERIALS AND METHODS: We estimated associations between monthly mean concentrations of PM < 10 μm and 2.5-10 μm in diameter (PM 10; PM 2.5-10) with time-domain measures of heart rate variability (HRV) and QT interval duration (QT) among U.S. women and men in the Women's Health Initiative and Atherosclerosis Risk in Communities Study (n HRV = 82,107; n QT = 76,711). Then we examined mediation of the PM-HRV and PM-QT associations by DNA methylation (DNAm) at three Cytosine-phosphate-Guanine (CpG) sites (cg19004594, cg24102420, cg12124767) with known sensitivity to monthly mean PM concentrations in a subset of the participants (n HRV = 7,169; n QT = 6,895). After multiply imputing missing PM, electrocardiographic and covariable data, we estimated associations using attrition-weighted, linear, mixed, longitudinal models adjusting for sociodemographic, behavioral, meteorological, and clinical characteristics. We assessed mediation by estimating the proportions of PM-HRV and PM-QT associations mediated by DNAm.
RESULTS: We found little evidence of PM-HRV association, PM-QT association, or mediation by DNAm.
CONCLUSIONS: The findings suggest that among racially/ethnically and environmentally diverse U.S. populations, sub-chronic exposures to coarser particulates may not exert appreciable, epigenetically mediated effects on cardiac autonomic function or ventricular repolarization. Further investigation in better-powered studies is warranted, with additional focus on shorter duration exposures to finer particulates and non-electrocardiographic outcomes among relatively susceptible populations.
Bibliographical noteFunding Information:
The Atherosclerosis Risk in Communities study has been funded in whole or in part with Federal funds from the National Heart, Lung, and Blood Institute (NHLBI) , National Institutes of Health , Department of Health and Human Services (contract numbers HHSN268201700001I , HHSN268201700002I , HHSN268201700003I , HHSN268201700004I and HHSN268201700005I ). The authors thank the staff and participants of the ARIC study for their important contributions. Funding was also supported by 5RC2HL102419 and R01NS087541 .
This work was supported by National Institute of Environmental Health Sciences ( NIEHS) grant R01-ES020836 (LH, AB, EAW), NHLBI contract HHSN268201100046C (KC), NIEHS grant R01-ES017794 (EAW), NHLBI National Research Service Award T32-HL007055 (RG), NIEHS National Research Service Award T32-ES007018 (KH), and NCI grant R25-CA094880 (KJ) .
The WHI program is funded by the NHLBI , U.S. Department of Health and Human Services, through contracts HHSN268201100046C , HHSN268201100001C , HHSN268201100002C , HHSN268201100003C , HHSN268201100004C , and HHSN271201100004C . WHI-AS311 was supported by American Cancer Society award 125299-RSG-13-100-01-CCE . WHI-BAA23 was supported by NHLBI's Broad Agency Announcement contract HHSN268201300006C . WHI-MIMS was supported by Glaxo Wellcome (now GlaxoSmithKline ). All contributors to WHI science are listed at https://www.whi.org/researchers/Documents%20%20Write%20a%20Paper/WHI%20Investigator%20Long%20List.pdf .
© 2021 Elsevier Inc.
- DNA methylation
- Heart rate variability
- Particulate matter
- QT interval Duration
- Women's Health
- Air Pollution/adverse effects
- Air Pollutants/analysis
- Particulate Matter/analysis
- Environmental Exposure/adverse effects
- Atherosclerosis/chemically induced
PubMed: MeSH publication types
- Research Support, Non-U.S. Gov't
- Research Support, U.S. Gov't, P.H.S.
- Journal Article
- Research Support, N.I.H., Extramural