Differences in Serum Sex Hormone and Plasma Lipid Levels in Caucasian and African-American Premenopausal Women

Abstract

Risk of coronary heart disease is higher in African-American than in Caucasian women. The aim of this study was to evaluate the contribution of sex hormone levels, race, and measures of body fat to the variation in plasma lipid levels, a well-established risk factor for coronary heart disease. This was a cross-sectional study. The study was conducted in the general community. Sixty Caucasian and 117 African-American premenopausal women participated. Body weight, body mass index (BMI), and waist to hip circumference ratio (WHR), as well as plasma lipid and serum sex hormone levels, were assessed. Relative to Caucasian women, African-American women had significantly higher mean BMI (23.92 +/- 3.87 vs. 26.99 +/- 5.87 kg/m2, respectively; P < 0.001), and WHR (0.733 +/- 0.052 vs. 0.757 +/- 0.068; P < 0.03). Also, plasma triglyceride (TG) levels were significantly lower in African-American women (81 +/- 61 vs. 55 +/- 24 mg/dl; P < 0.0001). Serum estrone sulfate (556 +/- 323 vs. 442 +/- 332 pg/ml, Caucasian vs. African-American; P < 0.001), estradiol (E2) (55.1 +/- 43.6 vs. 35.8 +/- 17.7 pg/ml; P < 0.0001), androstenedione (2.6 +/- 0.9 vs. 1.6 +/- 0.7 ng/ml; P < 0.0001), and testosterone (0.36 +/- 0.12 vs. 0.31 +/- 0.19 ng/ml; P < 0.002) levels were significantly lower in African-American women than in Caucasian women. After correction for the effects of age, BMI, and WHR, serum E2 levels were significantly and positively associated with plasma high-density lipoprotein cholesterol levels in all women, and serum estrone sulfate levels with plasma total cholesterol and TG levels in African-American women. Our results indicate that race is an important determinant of plasma TG and serum sex hormone levels, even after adjustment for differences in body size. A significant association between endogenous E2 and high-density lipoprotein cholesterol levels exists in premenopausal women, independent of their race.