Very low testosterone levels can kill

Low testosterone levels can increase the risk of early death from heart disease and other causes, according to new research.

The heart health of 930 men, all of whom had heart disease and had been referred to a specialist heart centre between 2000 and 2002, was tracked for around 7 years. Almost twice as many men with low testosterone died as did those with normal levels. One in five of those with low testosterone died, compared with one in eight of those with normal levels.

It should be stressed that we are talking here about clinically low levels of testosterone called hypogonadism rather than the natural tailing off of testosterone with age.

In fact of the 930 men, low testosterone was relatively common at the time of referral. One in four of the men was classified as having low testosterone. (This is defined as levels of either bioavailable testosterone or bio-T – testosterone available for tissues to use - of under 2.6 mmol/l or total testosterone of under 8.1 mmol/l.) But borderline levels of low total testosterone (15.1mmol/l) also increased the risk of an early death.

A low bio-T level was an independent risk factor for premature death from all other causes as well as heart disease, after taking account of other factors, such as age, other underlying health problems, smoking and weight.

Testosterone replacement therapy

What does this mean? Should men be having hormone replacement therapy to build up testosterone levels?

According to an editorial in the BMJ’s Heart magazine in which this research first appeared, there is increasing interest in looking at testosterone replacement or TRT. But the authors warn that it is not without its risks which include prostate cancer.

MHF trustee and GP Dr Howard Stoate said: ''This is well-designed study linking low testosterone levels to increased mortality. However, it only looked at men who already have heart disease. What we don't yet know is whether taking testosterone supplements can prevent heart diesase or improve survival. I hope this will trigger researchers to carry out further research leading to treatments which could prevent many early deaths in men.'

We know that high levels of testosterone as found in anabolic steroids, for example, are dangerous. High testosterone in women also boosts the risk of diabetes and cardiovascular disease. But research into the benefits of testosterone, which has taken a back seat for many years in favour of looking at the impact of female homones, could be back on the table.