Benefits of testosterone therapy on the cardiovascular system

T. Hugh Jones, MD, MB, ChB, BSc, MRCP, FRCP, Centre for Diabetes and Endocrinology, Barnsley District General Hospital, United Kingdom

During the 1940s several studies consistently claimed that administration of testosterone proprionate improved anginal symptoms in the majority of patients treated. More recently, it has been shown that intravenous testosterone acutely reduces myocardial ischemia and dilates coronary arteries. Testosterone replacement to physiological levels over 1 to 3 months significantly reduces the time to ischemia (1mm ST depression) in men with chronic stable angina as an add-on to their usual antianginal medication. The lower the baseline testosterone the greater the improvement in time to ischemia. There is accumulating evidence that men with CHD have a high prevalence of hypogonadism and low normal levels of testosterone (<12nmol/l). Long term studies will be needed to determine whether or not testosterone replacement therapy will reduce cardiovascular outcome.

The mechanism by which testosterone improves myocardial ischemia under physiological conditions has not been fully elucidated. In vitro, supraphysiological levels of testosterone are required to isolated coronary arteries and this has been the major argument against a physiological role of this hormone. We have recently demonstrated that testosterone, at physiological concentrations inhibits extracellular calcium entry via voltage-gated calcium channels using patch-clamping and calcium fluorescence techniques.

Chronic congestive heart failure is a condition poor quality of lie and survival prognosis similar to that of many cancers. A double-blind placebo controlled study using testosterone esters by intramuscular injection has shown that there was a significant improvement in functional exercise capacity and quality of life in the testosterone treated group. A one-year study is in progress. Acute administration of testosterone in CHF patients reduced peripheral vascular resistance and enhanced cardiac index.

In summary, recent research provides evidence that testosterone replacement therapy may have a role to play in men with heart disease.