Forty per cent of men over age 45 suffer from testosterone deficiency but few are actually treated for it, says a Canadian doctor who reviewed guidelines for the condition.
Less than 5 per cent are diagnosed and treated for the condition, Dr. Richard Bebb, a endocrinologist in Vancouver, wrote in the November issue of the B.C. Medical Journal.
Hypogonadism is the formal term for male menopause or andropause.
After the age of 30, testosterone levels decrease about 1.5 per cent a year.
Symptoms of hypogonadism include:
Mood changes such as irritability or increased sadness.
Decreased muscle bulk.
Decreased muscle strength.
Decreased ability to concentrate on tasks.
Lack of morning erections or less rigid erections.
Decreased volume of ejaculate.
Physical signs can include more central body fat, osteoporotic fractures, and height loss, Bebb noted.
Confirming a diagnosis involves symptoms of androgen deficiency, unequivocal blood test results of low testosterone levels and a positive response to testosterone replacement therapy, he said.
Testosterone replacements can be given by injection, patch or orally.
The long-term safety of testosterone replacement therapy is unknown.
In the New England Journal of Medicine last year, doctors reported a six-month study on men over the age 65 who used a testosterone gel showed that there was a higher rate of cardiac problems in the men using the hormone, compared to men on a placebo.
More of the participants getting the treatment had high blood pressure or high cholesterol levels that predisposed them to cardiovascular disease, Bebb noted.
The U.S. National Institutes of Health is sponsoring a large study to clarify the long-term cardiovascular effects of testosterone therapy in men.
Bebb said it is generally recommended that men with prostate cancer not be treated with androgens to avoid the possibility of the hormones accelerating tumour growth.
The production of sperm gets suppressed even more when hypogonadal men are given testosterone, so men who want to be fertile should be told about that side-effect.
Doctors should also be on alert for misuse of androgens by athletes, Bebb said.