Jul 9 2007
Post-menopausal women with lower levels of testosterone are more likely to suffer from heart disease. Research, published in the June edition of the European Journal of Endocrinology, shows that higher testosterone levels in post-menopausal women may have a protective effect against cardiovascular disease.
Researchers led by Dr Erik Debing at the Free University of Brussels in Belgium examined the levels of sex hormones in natural post-menopausal women (i.e. those not taking hormone replacement therapy) and their association with the presence of atherosclerosis. Atherosclerosis is a condition where the arteries become hardened and blocked by the deposition of substances such as cholesterol. It is commonly seen as a precursor to heart disease. The research team examined 56 post-menopausal women who had atherosclerosis of the carotid artery (the artery that supplies blood to the head and neck) and compared the levels of sex hormones in their blood with 56 age-matched controls.
While they found no significant difference between the levels of other sex hormones, women with atherosclerosis had significantly lower testosterone levels than women who were free from the disease (0.23±0.12 vs. 0.31±0.20 µg/l). Even after the researchers had controlled for other risk factors associated with heart disease (such as diet, high blood pressure, smoking and diabetes), the relationship between low testosterone levels and atherosclerosis remained strong.
Although the hormone testosterone is usually associated with men, women also produce some testosterone, mainly from their ovaries and adrenal glands. Testosterone performs many essential functions in the bodies of both men and women including maintaining muscle strength and bone density. While statistics show that the risk of heart disease increases in post-menopausal compared to pre-menopausal women, the reasons for this have remained unclear.
Traditionally seen as a male disease, heart disease is now one of the leading causes of death in post-menopausal women in Europe. This is the first time that a case-control study has been carried out, directly comparing the levels of sex hormones in post-menopausal women with and without atherosclerosis of the carotid artery. Further work is now required to enhance our understanding of the mechanisms behind this relationship and the implications for health provision.
Researcher Dr Erik Debing said:
"This is the first time that a case-control study has found that post-menopausal women with athlerosclerosis have lower testosterone levels. Athlerosclerosis is the main precursor to heart disease, one of the major causes of death in post-menopausal women. Our work suggests that higher levels of testosterone may have a protective role against atherosclerosis in women who have undergone the menopause.
This research represents an important step forward in our understanding of the causes of atherosclerosis and will allow us to develop more effective treatments and advice. We now need to carry out further research to examine why low testosterone levels in post-menopausal women may predispose them to develop cardiovascular disease."