Sung Kyun Park
The accumulation of lead in the tibia was associated with resistant hypertension, according to a study published in the Journal of the American Heart Association.
“Once lead enters the body, it is very difficult to remove it,” Sung Kyun Park, ScD, MPH, associate professor in the departments of epidemiology and environmental health sciences at the University of Michigan School of Public Health, told Cardiology Today. “It stays several decades in your hard bones. When you get old and your bones get weak, lead can be released to the bloodstream and interfere with blood pressure control. Therefore, the most important clinical and public health implication of our study is to prevent lead exposure early in life.”
To examine the risk of resistant hypertension in relation to bone lead levels, researchers conducted a prospective cohort study of the Veterans Affairs Normative Aging Study, a longitudinal cohort study of 475 male volunteers aged 21 to 80 years (97% white).
Data on systolic BP, diastolic BP, antihypertension medication, lead in the blood, lead in the patella bone, lead in the tibia bone and demographic and confounding variables were considered.
Researchers defined resistant hypertension as systolic BP greater than 140 mm Hg or diastolic BP greater than 90 mm Hg while on three medications or requiring more than four medications for BP control.
Among the cohort, 20.4% of participants had resistant hypertension, with median tibia and patella lead levels of 20 µg/g and 25 µg/g, respectively.
The researchers found an association between resistant hypertension and a per interquartile range (IQR) increase in tibia lead, defined as 13 µg/g to 28.5 µg/g (RR = 1.19; 95% CI, 1.01-1.41).
No associations between resistant hypertension and patella lead per IQR increase, defined as 18 µg/g to 40 µg/g (RR = 1.1; 95% CI, 0.92-1.31), were found. There was also no relationship observed between resistant hypertension and blood lead levels (RR = 1.11; 95% CI, 0.88-1.4).
“Our study should be replicated in other populations,” Park said in an interview. “We also want to test in the future if dietary intervention, such as calcium intake or physical activity, can mitigate the observed lead effect on resistant hypertension.” – by Melissa J. Webb
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Sung Kyun Park, ScD, MPH,
can be reached at email@example.com.
Disclosures: The authors report no relevant financial disclosures.