Experts know one thing for sure – being male is a cardiovascular risk factor in itself. You can alter many of the lifestyle risks, from being overweight to smoking, but you can’t eradicate the Y chromosome. Death rates from coronary heart disease are four to five fold higher in men, than women, in the under 65s, according to the British Heart Foundation.
Yet, men do not suffer from raised cholesterol more than women and are only slightly more vulnerable to high blood pressure. A slightly greater number of men are obese, but it’s unlikely this alone accounts for the disparity.
Now, some doctors are considering a more complex basis for male heart disease around hormone levels. Much the same way women’s risk of cardiovascular disease is predicated on diminishing oestrogen levels, could some men’s risk of suffering angina – the chest pain or discomfort that occurs if an area of your heart muscle doesn’t get enough oxygen-rich blood – and even having heart attacks, be due to low or non-existent levels of testosterone?
The connection was first made in 1941, followed by an article appearing in Time magazine in 1942 claiming testosterone replacement therapy (TRT) could improve the symptoms of angina. But it wasn’t until the 1990s, when a group led by endocrinologist Professor Hugh Jones of Barnsley Hospital NHS Foundation Trust and the University of Sheffield with Professor Kevin Channer of Sheffield’s Royal Hallamshire Hospital began to unpick the evidence, that a link became clearer.
It would seem men need normal testosterone levels not just to function sexually, but also perhaps to survive into older age
“We learnt testosterone could dilate arteries if injected right into them,” explains Professor Jones, “and laboratory studies showed it acts like a commonly used anti-anginal drug nifedipine.”
Further investigation showed that up to 40 per cent of men with existing heart disease had low or low-to-normal testosterone levels. In 2010, the team published a paper in the journal Heart which showed that, where testosterone levels were low and heart disease existed, men were twice as likely as normal to be dead in seven years.
It would seem men need normal testosterone levels not just to function sexually, but also perhaps to survive into older age. One theory why is fascinating: when animals are sick, cells called cytokines produced by the immune system suppress the production of hormones made in the pituitary gland. This causes testosterone levels to fall, presumably so that they cannot reproduce equally sickly infants. The lack of the hormone also means these animals will die off sooner as they are superfluous to requirements.
Could low testosterone be an indicator of previous or present illness, apart from heart disease?
Professor Jones’s group has found strong links between low testosterone, and obesity and type 2 diabetes, both also risk factors for heart disease. His most recent study, published last month online, shows that men with type 2 diabetes and low testosterone are 2.3 times more likely to be dead at the end of six years than patients with normal levels.
“Testosterone replacement in diabetic men with deficiency improves insulin sensitivity,” he says, “plus it reduces central fat and lowers cholesterol, all of which are well-known cardiovascular risk factors.
“And the evidence suggests that replacing testosterone to the normal range is safe from a cardiovascular point of view provided patients are monitored carefully as guided by international clinical recommendations.”
What is required to firmly support current evidence is a large placebo-controlled multi-centre trial over a five-year period. This may not be feasible due to great cost of this type of study and ethical issues. Getting the message out about testosterone deficiency to the public and the medical profession remains difficult, but the good news is there is a simple and effective treatment.
QUESTIONS TO ASK YOUR PARTNER
1. Should you be taking HRT?
Many women were put off hormone replacement therapy after the Million Women Study showed a link between oestrogen therapy and increased risk in breast and ovarian cancer. Other studies have shown a possible protective effect of HRT on the heart. “When you look closely at the first study, the numbers of women with cancer are very small,” says Dr Adam Fitzpatrick, consultant cardiologist at BMI Healthcare and the Manchester Royal Infirmary. “And the study group was aged over 60 and not menopausal. If you are young or your menopause symptoms are intolerable, it is better to be on HRT than not.”
2. Are you getting palpitations?
Atrial fibrillation (AF) affects one million people in the UK and the numbers are rising rapidly. “Many people may experience the occasional palpitation – a transient bump and somersault sensation,” says Dr Fitzpatrick. “This is benign in most cases. But if you can feel sustained or irregular, rapid palpitations, you need to seek help, especially if you are getting tired or breathless, and are aged over 65. Do ask your GP for an ECG to rule out AF, although ideally this must be carried out while the palpitations are occurring.” AF may also be associated with fainting or chest pain.
3. Are you still smoking?
One in five women smoke and the British Heart Foundation warns that smokers have twice the risk of a heart attack compared to those who have never smoked. Research also shows that non-smokers, who live with smokers, have a greater risk of CVD than other non-smokers. Dr Fitzpatrick says: “Women’s coronary arteries are narrower than men’s so they will clog up quicker and female smokers will fare worse in a significant angina attack. It is more likely to become a heart attack.” Within a year of stopping smoking, your risk is reduced by about half. But quitting is immediately beneficial and it’s never too late to stop.
