Objective: The goal of this study was to investigate the potential role of sex hormones in coronary atherosclerosis in both men and postmenopausal women.

Design: A total of 258 male and 236 female postmenopausal participants with angiographically defined stable coronary artery disease (CAD) were enrolled. We measured the levels of estradiol (E2), progesterone (P), testosterone (T), follicle-stimulating hormone, and luteinizing hormone in the participants and in 156 male and 132 female disease-free and age-matched controls using commercially available radioimmunoassay kits.

Results: In the male study participants and control subjects, the levels of E2 and P differed slightly in opposing directions; however, these differences were not significantly different, nor were there significant differences in T. However, the ratio of E2 to P in participants was significantly (P < 0.01) lower (even after adjustments for age and body mass index) than in the control subjects (mean +/- SEM: 70.2 +/- 56.4 vs 90.7 +/- 59.5, respectively). In the postmenopausal women, a slight decrease in E2 and increases in P and T in participants were not significantly different from levels in the control group. However, the E2 to P and E2 to T ratios were significantly (P < 0.01) lower (before and after adjustments for age and body mass index adjustments) in the participants relative to the control subjects (38.7 +/- 28.4 vs 49.6 +/- 36.3 and 46.5 +/- 37.6 vs 60.6 +/- 40.8, respectively). Correlation analyses demonstrated that the sex hormone ratio changes in both men and postmenopausal women were related with atherogenic blood lipoprotein changes. In both the male and female groups, levels of follicle-stimulating hormone and luteinizing hormone did not differ significantly between the participants and controls, and correlation analyses revealed no association between these hormones and the ratio of E2 to P in males and the ratios of E2 to P and E2 to T in females (r < 0.2, P > 0.05). Multiple regression analyses demonstrated that age and the presence of CAD were significantly and independently associated with the E2-to-P ratio in men and the E2-to-P and E2-to-T ratios in women and that E2-to-P ratio and low-density lipoprotein cholesterol level were significant independent predictors of CAD in males; E2-to-P and E2-to-T ratios and low-density lipoprotein cholesterol level were significant predictors of CAD in women.

Conclusions: In both men and postmenopausal women with angiographic CAD, there were significant differences (relative to age-matched control subjects) in sex hormone ratios, suggesting an abnormality that could influence coronary health. A lower E2-to-P ratio may be associated with the male disposition to coronary atherosclerosis, whereas lower E2-to-P and E2-to-T ratios may be associated with the same condition in females.