December 04, 2022
2 min read
Higher levels of novel tibia and blood epigenetic biomarkers of lead exposure were associated with increased CVD mortality risk in American Indian men, researchers reported.
“This analysis builds on the development of bone and blood lead epigenetic biomarkers and is the first study to evaluate their relation with cardiovascular outcomes,” Wil Lieberman-Cribbin, MPH, PhD student at Columbia University, and colleagues wrote in the Journal of American Heart Association.
For the prospective cohort study, Lieberman-Cribbin and colleagues evaluated the relationship between epigenetic biomarkers of lead exposure and CV health in 2,321 American Indian adults aged 45 to 74 years from the Southwest and Great Plains regions who were recruited between 1989 and 1991 for the Strong Heart Study (SHS).
Participants completed baseline questionnaires, laboratory analyses and physical examinations that tested for age, sex, education, place of recruitment, smoking status, BMI, lipid levels, hypertension treatment and diabetes.
In the study, incident CVD was defined as CHD, stroke or HF. CVD outcomes and deaths were identified via field centers, the coordinating center and surveillance reporting, and then reviewed by the Morbidity and Mortality Review Committee.
All participants were assessed for lead epigenetic biomarkers in blood (eBlood), tibia (eTibia) and patella (ePatella).
In the study, researchers found that none of the tibia, blood or patella lead biomarkers were significantly associated with CVD incidence.
However, tibia lead (adjusted HR per doubling increase = 1.42; 95% CI, 1.07-1.87) and blood lead (aHR per doubling increase = 1.57; 95% CI, 1.16-2.11) were associated with CVD mortality, but patella lead was not, Lieberman-Cribbin and colleagues found.
For eBlood lead, the risk for CVD incidence was higher in North Dakota/South Dakota (HR = 1.27; 95% CI, 1.13-1.42; P = .002) than in Arizona (HR = 1.04; 95% CI, 0.78-1.38; P = .002) and Oklahoma (HR = 0.95; 95% CI, 0.84-1.07; P = .002).
In addition, men had a higher CVD mortality risk due to high levels of eTibia (HR = 1.42; 95% CI, 1.17-1.72) than women (HR = 1.04; 95% CI, 0.89-1.23; P for interaction = .014), the researchers wrote.
“The present study adds to the weight of evidence of DNA [methylation]-based biomarkers to predict disease risk in the SHS,” Lieberman-Cribbin and colleagues wrote. “Future work must perform further validation of these lead epigenetic biomarkers in different populations, given their potential to capture disease risk.”