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.