Testosterone and cardiovascular risk in men.

Testosterone deficiency is highly prevalent in men with cardiovascular disease (CVD) and is associated with an increased mortality. Low testosterone also has an adverse effect on several cardiovascular risk factors, which include insulin resistance, diabetes, dyslipidaemia, central adiposity and endothelial dysfunction. Male gender is a well-recognised risk factor for premature CVD and mortality. The question of whether or not testosterone deficiency is a contributory factor to atherogenesis or merely a biomarker of ill health arises. Animal studies and experiments on isolated cells indicate that many of the mechanisms intimate to the atherosclerotic process are beneficially modulated by testosterone. Epidemiological studies have shown that men with endogenous testosterone levels in the mid-upper normal range have reduced cardiovascular events and mortality compared to those with low or lower range, and with high range testosterone. Testosterone replacement in men diagnosed with hypogonadism where mid-normal range levels are achieved have shown a beneficial effect on several cardiovascular risk factors, cardiac ischaemia, functional exercise capacity and improved mortality. Yet studies where patients were either undertreated or given high-dose testosterone have been associated with an increased risk of cardiovascular-related events. Clinical monitoring and titration of testosterone dose is therefore of paramount importance.