Reduced testosterone linked to increased mortality

The exact reasons for the age-related decrease in testosterone levels are unknown. It is probably due to a combination of factors including an increase in body fat mass (and an associated increase in aromatase activity), oxidative damage to testosterone-producing tissues and a decline in precursor molecules such as DHEA.

A report published in the November 2010 issue of the British journal Heart revealed an increased risk of cardiovascular disease and death from all causes in men with deficient testosterone levels.

The study involved 930 men with heart disease who were undergoing coronary angiography at a specialist cardiac centre. Baseline serum levels of total testosterone and free testosterone were measured.

Volunteers were monitored for more than six years, during which time 129 deaths occurred, 73 of which were cardiovascular-related. Twenty-four per cent of subjects had low levels of testosterone or free testosterone.

The use of aspirin or beta-blockers was associated with a lower mortality risk but with an increased risk associated with heart failure and a reduction in free testosterone.

Twenty-two per cent of subjects presenting with testosterone deficiency died from various causes over the course of the study, against twelve per cent of those with normal testosterone levels. In addition, low levels of free testosterone were associated with an increased risk of cardiovascular-related death.

In an editorial accompanying the publication of this study, the researchers commented on these results: “Clinical studies of testosterone supplementation in men with low testosterone are associated with decreased visceral adiposity, improved insulin sensitivity and an improved metabolic profile. Studies on subjects with cardiovascular disease also suggested beneficial effects, with improved functional capacity in cases of heart failure and improved symptoms in subjects with coronary artery disease.” (Heart, 2010 ;96 : 1821-1825)