Abstract 13804: Extremes of Aromatase Activity Predict Increased 25 Year Risk of Cardiovascular Mortality in Postmenopausal Women: The Rancho Bernardo Study
Objective: Peripheral conversion of androgens to estrogens via aromatase is the primary source of estrogen in postmenopausal women and may play a role in cardiovascular health. This study examines the prospective association of an indirect measure of aromatase activity with CVD mortality among community-dwelling postmenopausal women.
Design: The association of an index of aromatase activity (AROM), the serum estrone (E1) to androstenedione (A) ratio, with CVD mortality was examined in 817 non-estrogen treated postmenopausal women aged 50–90 (mean=72) years at baseline (1984–87) who were followed for mortality through April, 2009.
Results: During the 25 year follow-up, 247 deaths were attributed to CVD. The 95% range for AROM (x100) was 1.6 to 12.6. AROM was positively associated with age, overall adiposity (BMI) and central adiposity (waist-to-hip ratio) (all P>.01). In an age, adiposity, and lifestyle adjusted proportional hazards regression the risk for CVD mortality was significantly higher for women in the lowest (HR=2.0, p=.002) and highest (HR=1.5, p=.043) quintiles of AROM, compared to the middle quintile, suggesting a U-shaped association (Figure 1). Separate analyses adding adjustment for classic CVD risk factors, excluding women with prevalent CVD (n=103), or excluding women with diabetes (n=114) diminished the association for high, but not low, AROM. Excluding deaths that occurred during the first 2 yrs of follow-up did not alter results. E1 and A levels alone did not predict CVD mortality. Estradiol did not influence these associations and was not independently related to CVD mortality risk in separate models. AROM was not related to non-CVD death (N=260).
Conclusion: These results suggest that aromatase is a novel endocrine factor predictive of CVD mortality among postmenopausal women. If confirmed, additional studies are needed to determine whether extremes of aromatase reflect genetic influences or underlying disease processes.
- © 2010 by American Heart Association, Inc.