Cardiovascular Disease (CVD) refers to diseases of the heart and blood vessels. Examples of diseases in this category are congestive heart failure, coronary artery disease, angina, high blood pressure and stroke.
Cardiovascular disease, in many cases, is caused by atherosclerosis - an excess build-up of plaque on the inner wall of a large blood vessel, which restricts blood flow.
In a small observational study comparing men presenting for scheduled angiography, testosterone levels were significantly lower in males with coronary artery disease compared to men with normal coronaries. (1)
Literature suggests that exogenous testosterone (testosterone acquired from outside the body's own testosterone-making system) is associated with a reduced risk of cardiovascular disease and more favorable levels of certain risk factors for heart disease; however, the relationship between the development of cardiovascular disease and serum testosterone levels remains uncertain.
Elevated lipids and apoproteins in the blood are risk factors associated with cardiovascular diseases, in particular, high total cholesterol and high LDL (low density lipoprotein). These lipids are pro-atherogenic – they may form deposits in the walls of the blood vessels - whereas HDL (high density lipoprotein) is protective against these deposits.
There is a more consistent relationship with testosterone and other lipid fractions. Most studies of elderly or hypogonadal populations report reductions in total cholesterol, LDL and apo-protein B after treatment with exogenous testosterone.
A study measuring the effects of testosterone replacement on lipid levels in the hypogonadal population, showed reductions of up to 22% in total cholesterol and 15% in LDL.(2)
Hypertension (high blood pressure) is another established risk factor for coronary artery disease, and lowering high blood pressure reduces the risk of cardiovascular events. Testosterone levels have shown to be lower in populations of men with hypertension than in men with normal blood pressures. This may be because testosterone acts like a natural vasodilator (causing dilation of the blood vessels) by reducing peripheral vascular resistance; therefore, lowering blood pressure.
The purpose of secondary prevention in patients with vascular disease is to reduce the incidence of subsequent events, thus prolonging the duration and quality of life. There are well-established therapies for coronary disease that target the known cardiovascular risk factors. There is a lot of evidence that suggests that testosterone treatment in men has potentially beneficial effects on virtually all of the coronary risk factors, as well as an independent anti-atherogenic action. In addition, testosterone therapy improves the ischemic threshold and therefore the quality of life in patients with symptomatic coronary disease. This is important, since it is rare that a secondary prevention treatment can make a patient feel better.
(1) English KM, Mandour O, Steeds RP, Diver MJ, Jones TH, Channer KS. Men with coronary artery disease have lower levels of androgens than men with normal coronary angiograms. Eur Heart J 2000; 21:890–4.
(2) Zgliczynski S, Ossowski M, Slowinska-Srzednicka J, Brzezinska A, Zglicznski W, Soszynski P, Chotkowska E, Srzednicki M, Sadowski Z. Effect of testosterone replacement therapy on lipids and lipoproteins in hypogonadal and elderly men. Atherosclerosis 1996; 121:35–43.