Background: Hypertension is more common among men at younger ages and among women after age 60, suggesting a possible link between endogenous estrogens and systolic blood pressure (SBP). We tested whether serum 17beta-estradiol (E(2)) or any of its metabolites were associated with SBP among middle-aged and older adults.
Methods: Using a cross-sectional study design, we examined data from a population-based sample of 98 adults living in Cook County, Illinois. Age ranged between 55 and 69 years and body mass index (BMI) ranged between 19.8 and 50.6 kg/m(2). Serum was analyzed for 17beta-E(2) and 14 estrogen metabolites (EMs) using mass spectrometry. SBP was measured using a tonometric device that records a pulse wave at the radial artery. Demographic and health history information were obtained via questionnaires.
Results: Univariate analysis revealed an inverse relationship between SBP and both natural log (ln) 16alpha-hydroxyestrone (OHE(1)) (r = -0.360, P < 0.05) and ln 16-ketoestradiol (ketoE(2)) (r = -0.360, P < 0.05) among women but not men. No significant correlations were found between SBP and 17beta-E(2) in either sex. In multivariate analysis which adjusted for age, race, ethnicity, BMI, and use of cardiovascular medications, ln 16alpha-hydroxyestrone (16alpha-OHE(1)) (B = -5.3, s.e. = 2.1, P < 0.05) and ln 16-ketoE(2) (B = -4.7, s.e. = 1.9, P < 0.05) continued to be negatively associated with SBP among postmenopausal women.
Conclusions: These data suggest that serum 16alpha-OHE(1) or 16-ketoE(2) may be important for vascular health among postmenopausal women but not among similarly aged men.