Lead exposure tied to increased risk of CVD mortality: JAHA

Findings from the prospective Strong Heart Study (SHS) showed that higher epigenetic biomarkers levels of lead exposure estimated in blood and tibia (reflecting cumulative exposure) were tied to a higher risk of cardiovascular disease (CVD) and mortality."Our findings support that epigenetic biomarker of lead exposure may reflect some of the disease risk associated with the lead exposure," Wil Lieberman‐Cribbin and colleagues wrote in their study.

Lead is a cardiotoxic metal which is linked with several health effects. The researchers leveraged novel epigenetic biomarkers of lead exposure to examine their association with the incidence of cardiovascular disease (CVD) and mortality. Without data on bone lead exposure, epigenetic biomarkers can indicate cumulative lead exposure and body burden.

Mortality data and incidence of CVD were available through 2017. For this purpose, the researchers measured Blood DNA methylation using the Illumina MethylationEPIC BeadChip in 2231 participants of the SHS at baseline (1989–1991). They estimated epigenetic biomarkers of lead levels in the patella, blood, and tibia using previously identified cytosine‐guanine dinucleotide (CpG) sites. Median concentrations of lead epigenetic biomarkers in the patella, tibia, and blood were 21.3 μg/g, 13.8 μg/g, and 2.9 μg/dL, respectively.

The authors reported the following findings:

• In adjusted models, the hazard ratio (HR) of cardiovascular disease mortality per doubling increase in lead epigenetic biomarkers was 1.42 for tibia lead, 1.57 for blood lead, and 1.22 for patella lead. The hazard ratios for incident CVD were 0.99, 1.07, and 1.06.
• The association between the tibia lead epigenetic biomarker, and CVD mortality was modified by sex, with men at increased risk (HR, 1.42) compared with women (HR, 1.04).

"The findings showed that recently developed blood and tibia lead epigenetic biomarkers were tied to an increased risk of CV mortality, reflecting the cardiovascular impact of cumulative and ongoing lead exposures," the researchers explained.

"Further validation of these lead epigenetic biomarkers should be performed in future research in different populations, given their potential to capture disease risk," they concluded.

Tibia and blood lead biomarkers were tied to the SHS's increased CVD mortality risk. The association of blood and tibia lead biomarkers was modified by sex, with a positive association seen in men and no association found in women.

Reference:

Lieberman-Cribbin W, Domingo-Relloso A, Navas-Acien A, Cole S, Haack K, Umans J, Tellez-Plaza M, Colicino E, Baccarelli AA, Gao X, Kupsco A. Epigenetic Biomarkers of Lead Exposure and Cardiovascular Disease: Prospective Evidence in the Strong Heart Study. J Am Heart Assoc. 2022 Nov 16:e026934. doi: 10.1161/JAHA.122.026934. Epub ahead of print. PMID: 36382957.