Increasingly, more elderly men are using testosterone supplementation to improve their muscle mass, increase energy level, vitality and restore libido. This apparent restoration of 'youthfulness' is not without potential downsides.
IT was not too long ago that all women who became menopausal were routinely given hormone replacement treatment as it seemed logical to supplement the body with female hormones that were previously present.
Logic does not equal truth
However, the results of the Women's Health Initiative (WHI) randomised trial of female hormones on about 16,000 postmenopausal women
caused a major paradigm shift in the approach to female hormone replacement. The results of the study, published in the New England Journal of Medicine and the Journal of the American Medical Association, found that after an average follow-up of five years, the women on hormone replacement had higher risks of heart disease, stroke, clot formation in leg veins and breast cancer.
Most alarmingly, there was a significant 26 per cent increase in breast cancer incidence and breast cancers in women on hormone replacement were more likely to be at an advanced stage. As a result of these startling findings, guidelines have been changed and hormones are no longer given routinely to post-menopausal women. Hence, what appeared to be logical did not correlate with reality.
More recently, there has been an increasing trend to replace testosterone in men who have low testosterone levels. So, when the libido is low and there is a lack of energy, is it safe to provide male hormonal supplement? The WHI trial in women has taught us not to assume that replacing hormones when they decrease with age is safe. Hence, to make an informed decision, one has to look at the current evidence.
Testosterone and heart
Many research studies have shown that testosterone appear to have a beneficial impact on the heart. Many ageing males with low libido and general fatigue go on testosterone supplementation in a belief that the testosterone increases their physical strength and perhaps makes the heart stronger.
It may be heartening for them to know that laboratory studies on heart muscle cells have shown that a high testosterone level is associated with a lower tendency to develop an abnormal heart rhythm. Rat studies have also shown a similar association and hence, the current evidence suggests that testosterone may reduce the likelihood of developing an abnormal heart rhythm.
Testosterone can also improve blood flow by causing the heart artery wall to relax by a mechanism that appears to be a direct effect of the hormone on the blood vessel artery wall.
In addition, animal studies have also shown that testosterone seems to be able to protect the heart from injury due to insufficient oxygen and blood supply. Hence, studies in rats have shown that there is less heart muscle cell death and less heart muscle damage during a heart attack if there was testosterone supplementation, suggesting that the presence of testosterone can provide a beneficial protective effect on the heart. Although many studies appear to suggest that testosterone may reduce the likelihood of development of plaques in heart arteries, there is some conflicting data which suggests that we do not fully understand the mechanisms by which the hormone impacts heart arteries.
An anti-ageing panacea?
As testosterone decreases with increasing age, some men may experience reduced libido, decreased spontaneous erections, difficulty in sleeping, increased fat, decreased muscle mass, less energy, depression or difficulty in concentrating. Testosterone strengthens muscle mass and bone density, and maintains red blood cell production, sex drive and sperm production. Animal studies have also shown that testosterone supplementation reduces the fat within the abdomen, improve blood glucose levels and reduces mean blood pressure. However, there was no significant impact on cholesterol levels.
Increasingly, more elderly men are using testosterone supplementation to improve their muscle mass, increase energy level, vitality and restore libido. This apparent restoration of "youthfulness" is not without potential downsides. Testosterone supplementation can increase acne, result in excessive red blood cell production and blood thickening, worsen pre-existing sleep disturbances, increase hair loss, decrease sperm production, exacerbate prostate enlargement and increase activity of pre-existing prostate cancer.
Given these potential side effects of testosterone supplementation, it is generally not advised for males who have normal testosterone levels and who are generally healthy.
However, for males who have been found to have symptoms related to significant deficiency of testosterone (hypogonadism), testosterone supplementation has generally found to be safe and have generally increased their general well being.
For those who may potentially benefit from testosterone supplementation, their physicians will generally prescribe testosterone delivered through gel, patch, injection or implants. Oral testosterone is generally avoided as there is some concern that absorption through the gut may result in the hormone passing through the liver and causing an adverse impact on the liver.
Before you rush off to get your jab of testosterone to boost your "youthfulness", it will be best to discuss with your physician whether your symptoms are part of normal ageing, due to other medical conditions mimicking the effect of low testosterone levels or true deficiency of testosterone levels.
- Dr Lim is medical director at the Singapore Heart, Stroke & Cancer Centre. He is also editor-in-chief, Heart Asia (a journal of the British Medical Journal Publishing Group); chairman, scientific advisory board, Asia Pacific Heart Association; and honorary professor and senior medical adviser, Peking University Heart Centre
This series is brought to you by Heart, Stroke and Cancer Centre. It is produced on alternate Saturdays.