Lead and hypertension in a sample of middle-aged women.

Abstract

The role of lead exposure as a risk factor for hypertension is less well defined among women than among men. This case-control study assessed the relation of blood and bone lead concentrations to hypertension in women. Cases and controls were a subsample of women from the Nurses' Health Study. Hypertension was defined as a physician diagnosis of hypertension between 1988 and 1994 or measured systolic blood pressure > or = 140 mm Hg or diastolic blood pressure > or = 90 mm Hg. Mean (SD) blood lead concentration was 0.15 (0.11) mumol/L; mean tibia and patella lead concentrations by K-x-ray fluorescence were 13.3 (9.0) and 17.3 (11.1) micrograms/g, respectively. After adjustment for potentially confounding factors, an increase from the 10th to the 90th percentile of patella lead values (25 micrograms/g) was associated with approximately 2-fold (95% confidence interval = 1.1, 3.2) increased risk of hypertension. There was no association between hypertension and either blood or tibia lead concentrations. These findings support a potentially important role for low-level lead exposure as a risk factor for hypertension among non-occupationally exposed women.