Endogenous sex hormone levels in postmenopausal women undergoing carotid artery endarterectomy.

OBJECTIVE To study the endogenous sex hormone levels in natural postmenopausal women and their association with the presence of internal carotid artery (ICA) atherosclerosis. DESIGN Case-control study METHODS We compared 56 patients with severe ICA atherosclerosis referred for carotid artery endarterectomy (CEA) with 56 age-matched control subjects free of severe atherosclerotic disease. The presence of atherosclerosis was determined by high-resolution B-mode ultrasound. Metabolic parameters and sex hormones were measured or calculated: total cholesterol, high-density lipoprotein, low-density lipoprotein, triglycerides, glucose, insulin, quantitative insulin sensitivity check index, insulin resistance index, IGF-I, DHEA, DHEA sulfate (DHEA-S), free testosterone, total testosterone, estrone, estradiol, androstenedione, and sex hormone-binding globulin. RESULTS The cases had statistically significant lower levels of both total testosterone (0.23 +/- 0.12 vs 0.31 +/- 0.20 microg/l, P = 0.043) and free testosterone (3.42 +/- 1.94 vs 4.59 +/- 2.97 ng/l, P = 0.009) and significantly lower levels of androstenedione (625.3 +/- 168.7 vs 697.0 +/- 211.9 ng/l, P = 0.017) when compared with controls. Multivariate linear regression analysis, adjusted for traditional cardiovascular risk factors, baseline and physiologic characteristics, showed a significant inverse relationship between both serum free testosterone (beta = -0.234, P = 0.028) and androstenedione (beta = -0.241, P = 0.028) levels with the presence of severe atherosclerosis of ICA. CONCLUSIONS The study provides evidence of a positive association between low serum androgen levels and severe ICA atherosclerosis in postmenopausal women. It suggests that higher, but physiological, levels of androgens in postmenopausal women have a protective role in the development of atherosclerosis of ICA.