Abdominal Obesity, Insulin Resistance
A growing number of studies have linked androgen deficiency to insulin resistance, as well as increased abdominal obesity. These two factors are also common with men suffering from cardiovascular disease, and may directly contribute to (among other things) endothelial cell dysfunction and vascular damage. Androgen substitution has been shown in several studies to reduce midsection fat deposits, increase glucose tolerance, and improve the overall metabolic state. It has additionally been postulated that due to the important role of testosterone in managing insulin sensitivity, androgen deficiency may be a contributing factor to adult-onset (type 2) diabetes. Likewise, the substitution of testosterone in aging men with hypogonadism might reduce the likelihood of developing diabetes.
The endothelium is a layer of cells that lines the blood vessels throughout the entire circulatory system. These cells are responsible for managing the passage of some materials in and out of the blood vessels, and supporting the flow of blood through the system. Endothelial cells play a role in vasoconstriction and vasodilation, they regulate certain inflammatory processes, and they’re involved in blood clotting and in supporting the formation of new blood vessels. Endothelial dysfunction is linked to androgen deficiency in men, and may result in elevated blood pressure (hypertension), vascular ‘stiffness,’ and significantly increased risk of cardiovascular disease. Likewise, replacement of testosterone in men with a deficiency has been shown to improve endothelial function, blood vessel dilation, arterial vasoreactivity, and blood flow.
One additional important ‘endpoint’ of improvement to this therapy appears to be an increase in endothelial progenitor cell activity, which helps repair damage to the vascular system.
Traditionally, most physicians are extremely cautious with testosterone drugs. Many family doctors are very willing to prescribe estrogens to their female menopausal patients complaining of symptoms such as sexual dysfunction, but when it comes to their male patients with similar complaints, the response is often different. Many of these same physicians are much more willing to prescribe a drug like Viagra than the basic male androgen testosterone. Some mistakenly consider testosterone to be ‘too dangerous’ to give most of their patients, and reserve its use for extreme cases. And when testosterone is considered, it is given only for a very narrow and specific set of psychological or physical symptoms.
Of course in the era of AndroGel, some physicians are much more enlightened. Still, the troubling common fear of this hormone remains. Perhaps this is changing, and perhaps the accepted set of symptoms and therapies for prescribing this hormone is changing.
It seems clear that we can no longer paint testosterone as simply a ‘bad’ hormone for the cardiovascular system. While excessive high-level elevations of this hormone may indeed damage an individual’s cardiovascular health, we have strong evidence that within a certain physiological range, it may also protect the cardiovascular system from some of the same health issues. As such, its replacement may indeed turn out to be very important medical intervention for millions of men across the country, helping us to not only live better— but also live longer.
After all this time, it appears that this very controversial hormone, the same steroid demonized in the media, might actually help reduce the risk of cardiovascular disease in aging male patients. The study we reviewed this month is, likewise, something all men should take to heart— literally.
1. The Dark Side of Testosterone Deficiency: III. Cardiovascular Disease. Traish AM, Saad F et al. Journal of Andrology, April 2, 2009. ePub, Ahead of Print.