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Illustration credit:
Sylvain Leblanc
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Ever since the Women's Health Initiative
was prematurely halted for safety reasons in 2002, any
discussion about prescribing hormone therapy is bound
to incite debate. The use of testosterone-replacement
therapy (TRT) to treat symptoms of "male menopause,"
a rapidly growing field of research and an increasingly
common clinical concern, is certainly no exception.
While some physicians maintain
there just isn't enough data to be sure it's safe, others
say the concerns — namely that TRT increases the
risk of prostate cancer and heart disease — are
unfounded and that physicians' reticence is depriving
millions of Canadians of treatment. Experts debated
the merits of TRT at the recent 2nd North American Congress
on the Aging Male, held in Montreal in early February.
WHITHER
TRT?
The number of TRT prescriptions filled in Canada has
more than doubled since 1999 — to over 300,000
last year alone. But that number should be several orders
of magnitude higher still, according to Dr Andr� Guay,
a Harvard professor and endocrinologist who participated
in the recent debate. He says there's a persistent lack
of knowledge about testosterone deficiency in the medical
community at large. "Low testosterone and reproductive
hormones have fallen through the cracks. Those things
aren't treated much by endocrinologists, just by very
specialized centres now," he explains. "And until recently,
most doctors trained as FPs were trained in hospitals,
but low testosterone is not an inpatient issue."
Yet two to three million Canadians
will have testosterone deficiency in their lifetimes,
according to Dr Jay Lee, a University of Calgary urology
professor who also took part in the debate. He says
the majority of them are candidates for TRT — a
prospect that makes many physicians who are still unsure
of the treatment's safety very uneasy.
HEART
HEALTH
Though he admits more research is needed, Dr Guay says
TRT appears to be safe and effective for a variety of
health issues caused by testosterone deficiency, including
erectile dysfunction, low libido, osteoporosis, reduced
muscle mass and low energy. Even patients with metabolic
syndrome, he says, can benefit from TRT.
"There is a shift," agrees Dr Lee.
"In the old days, we all thought that testosterone was
bad for the heart, for example, because more men have
MIs and die of heart attacks [compared to women]. We
thought estrogen protects the heart, but now we know
it probably doesn't. In fact, low testosterone is associated
with heart problems."
Dr Lee is quick to point out that
although there is evidence that testosterone deficiency
is harmful to the heart and associated with metabolic
syndrome, there has never been an outcome study to measure
those relationships. A new meta-analysis, published
in the journal Mayo Clinic Proceedings in January,
however, did show that TRT is likely safe for the cardiovascular
system. Dr Lee, at least, is convinced — he regularly
prescribes TRT to men with metabolic syndrome as an
adjunctive treatment, to give them the extra energy
to start exercising.
PROSTATE
SAFETY
For many TRT-tenderfoots, the concern about the therapy's
purported connection to prostate cancer is even more
disquieting. "There are a lot of misconceptions," Dr
Guay counters. "A lot of people think it causes prostate
cancer, but there is no really good data that it does."
The link between testosterone and
prostate cancer was first proposed in 1941 by a Halifax-born
physician named Charles Huggins, whose work on the prostate
cancer-hormone relationship was so widely respected
that it garnered him the 1966 Nobel Prize for Physiology
or Medicine. But the literature has since discredited
the connection.
"One of the principles of evidence-based
medicine is that concepts that fail to withstand scientific
scrutiny are to be discarded," wrote one of the field's
current leaders, Dr Abraham Morgentaler, in European
Urology in October of last year. "Such a time has
come for the belief that testosterone causes enhanced
growth of prostate cancer."
TRT should not, however, be prescribed
to patients who have prostate cancer already, warns
Dr Lee.
DIAGNOSIS
411
So how do you know if your patient is suffering from
testosterone deficiency? It's clear that testosterone
levels decrease with age and that the hormone loss can
be exacerbated by stress, anxiety and chronic illness,
adds Dr Guay. Diabetics often have testosterone deficiency,
as do men with sleep apnea, osteoporosis and erectile
dysfunction (ED). "If you check every man who comes
into your office with ED, only 5-8% will have low testosterone,"
says Dr Lee. "If someone has low libido plus ED, that
goes up to 20-25%. Then, of those with ED who fail on
an ED drug, 35% of them will have low testosterone."
But you'll need to get biochemical
tests (salivary tests and blood tests are available)
to diagnose a patient with certainty, explains Dr Guay,
because some of the symptoms can coincide with those
common in depression or low thyroid function.
Dr Guay accepts that some doctors
have concerns about TRT, but he insists that it can
be of great benefit for the right patients.
"There is some risk," acknowledges
Dr Lee, of some potential side effects such as skin
irritation, benign prostate growth and urinary problems,
gynecomastia, infertility and others. "But as long as
you are checking on [your patients] often and talking
to them about the pros and cons," he says, "I believe
you are doing them a great service."
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