Association of low-level blood lead and blood pressure in NHANES 1999-2006.

This study investigated whether low blood-lead levels (≤10 μg/dL) were associated with blood pressure (BP) outcomes. The authors analyzed data from National Health and Nutrition Examination Survey 1999-2006 and participants aged 20 years or older. Outcome variables were systolic and diastolic BP measurements, pulse pressure, and hypertension status. Multivariable linear and logistic regressions stratified by race/ethnicity and gender were performed. Blood lead levels (BLL) were significantly correlated with higher systolic BP among black men and women, but not white or Mexican-American participants. BLLs were significantly associated with higher diastolic BPs among white men and women and black men, whereas, a negative association was observed in Mexican-American men that had, also, a wider pulse pressure. Black men in the 90th percentile of blood lead distribution (BLL≥3.50 μg/dL) compared to black men in the 10th percentile of blood lead distribution (BLL≤0.7 μg/dL) had a significant increase of risk of having hypertension (adjusted POR=2.69; 95% CI: 1.08-6.72). In addition, blood cadmium was significantly associated with hypertension and systolic and diastolic blood. This study found that, despite the continuous decline in blood lead in the U.S. population, lead exposure disparities among race and gender still exist. Published by Elsevier Inc.