Testosterone administration has cardio protective effects in men, particularly those with lower circulating levels of the hormone.

Dr. Giuseppe M. C. Rosano and others at the Istituto H. San Raffaele in Rome, Italy, write that the association between testosterone and coronary artery disease (CAD) is a controversial one. On the one hand, men have higher rates of cardiovascular disease than women, implicating testosterone as a cause of CAD. On the other hand, some studies suggest that testosterone may have beneficial effects on coronary arteries.

They randomized 14 men with CAD to either a placebo or testosterone, 2.5 mg IV in 5 minutes, followed by exercise testing at 30 minutes in a crossover design trial.

The Italian team reports "...that acute administration of testosterone improved exercise-induced myocardial ischemia in male patients with coronary artery disease." Specifically, testosterone significantly increased total exercise time and time to 1-mm ST-segment depression, as well as "...heart rate at the onset of 1-mm ST-segment depression and at peak exercise." Testosterone use also increased the "...rate-pressure product at the onset of 1-mm ST-segment depression..." compared with the placebo.

The findings suggest that that testosterone has significant cardio protective effects in men, Dr. Rosano and others say in the journal Circulation: Journal of the American Heart Association. The findings also help to "...explain the cardio protective effect of testosterone supplementation in men with hypotestosteronemia."

And while all the men in the trial appeared to benefit from testosterone administration, the hormone's anti-ischemic effects were greatest in men with lower baseline testosterone levels.

Circulation 1999;99:1666-1670.