Testosterone and estrogen balance (men). Recent studies suggest that testosterone-replacement may improve the symptoms of vascular disease.

From: http://www.lef.org/protocols/heart_circulatory/coronary_artery_disease_atherosclerosis_03.htm

Testosterone and estrogen balance (men). Recent studies suggest that testosterone-replacement may improve the symptoms of vascular disease. A placebo-controlled crossover study in men with ischemic heart disease and low testosterone levels reported that exercise time and the time to development of ischemic changes on a treadmill test were both increased with testosterone-replacement therapy (Malkin, 2004).
It has been shown that men with lower levels of testosterone have poorer endothelial function. In a study of 187 males, researchers found that those men in the highest quartile of testosterone levels had 1.7 fold greater flow mediated dilation, a marker of endothelial function (Akishita, 2007).
In another study, researchers examined the correlation between testosterone levels and mortality in over 900 men with coronary heart disease. The team found that the mortality rate in patients with testosterone deficiency was 21%, while only 12% of subjects with normal testosterone levels died. The authors of the study concluded that “in patients with coronary disease testosterone deficiency is common and impacts significantly negatively on survival” (Malkin, 2010).
Researchers analyzed 30-day survival data for 126 men who had suffered a heart attack. All of the men who did not survive were found to have low total testosterone levels (<= 300 ng/dL). The team went on to conclude that “a low level of testosterone was independently related to total short-term [post-heart attack] mortality (Militaru, 2010).
Testosterone levels are also inversely associated with the development of coronary artery disease. In a study of men 45 years of age or younger, researchers found that subjects with diagnosed coronary artery disease had significantly lower levels of free testosterone than did healthy, age-matched controls. The researchers went on to caution that, based on their findings, “a low level of free testosterone may be related to the development of premature coronary artery disease” (Turhan, 2007).
Italian researchers compared plasma testosterone levels of 119 elderly men with isolated systolic hypertension to those of 106 nonhypertensive elderly men. All the study participants were 60 to 79 years old, non-obese, nondiabetic, and nonsmokers. The hypertensive men were found to have 14% lower levels of testosterone compared to the nonhypertensive men. In both the hypertensive and nonhypertensive men, low testosterone levels correlated with higher blood pressure values (Fogari, 2003).
In a study of over 11,000 men, followed for up to 10 years, baseline testosterone concentrations were inversely associated with cardiovascular and all-cause mortality. Men with total testosterone levels of 481 ng/dL or greater at baseline were significantly less likely to die of cardiovascular disease or any cause during the follow-up period compared to men with testosterone levels below 481 ng/dL. The correlation held even after adjustment for various other confounding factors. The authors of this study declared that “low testosterone may be a predictive marker for those at high risk of cardiovascular disease” (Khaw, 2007).
A study published in the Journal of the American Medical Association (JAMA) measured blood estradiol (a dominant estrogen) in 501 men with chronic heart failure. Compared to men in the balanced estrogen quintile, men in the lowest estradiol quintile were 317% more likely to die during a 3-year follow-up, while men in the highest estradiol quintile were 133% more likely to die (Jankowska, 2009).
The men in the balanced quintile—with the fewest deaths—had serum estradiol levels between 21.80 and 30.11 pg/mL. This is very similar to the optimal range that Life Extension has long recommended for aging men. The men in the highest quintile who suffered 133% increased death rates had serum estradiol levels of 37.40 pg/mL or above. The lowest estradiol group that suffered a 317% increased death rate had serum estradiol levels under 12.90 pg/mL.
For more information on optimizing male hormone levels in order to prevent not only vascular disease, but many other age-related diseases as well, please review the chapter on Male Hormone Restoration Therapy.