A Harvard expert shares his thoughts on testosterone-replacement therapy
An interview with Abraham Morgentaler, M.D.
It might be stated that testosterone is the thing that makes men, men. It gives them their characteristic deep voices, big muscles, and body and facial hair, distinguishing them from women. It stimulates the development of the genitals , plays a role in sperm production, fuels libido, and leads to normal erections. It also boosts the production of red blood cells, boosts mood, and aids cognition.
As time passes, the "machinery" that makes testosterone slowly becomes less effective, and testosterone levels start to drop, by about 1 percent per year, beginning in the 40s. As guys get into their 50s, 60s, and beyond, they may begin to have signs and symptoms of low testosterone such as reduced sex drive and sense of energy, erectile dysfunction, diminished energy, reduced muscle mass and bone density, and nausea. Taken together, these signs and symptoms are often called hypogonadism ("hypo" significance low functioning and"gonadism" speaking to the testicles). Researchers estimate that the illness affects anywhere from two to six million men in the United States. Yet it's an underdiagnosed problem, with just about 5% of these affected receiving treatment.
Much of the current debate focuses on the long-held belief that testosterone can stimulate prostate cancer.
Dr. Abraham Morgentaler, an associate professor of surgery at Harvard Medical School and the director of Men's Health Boston, specializes in treating prostate ailments and male sexual and reproductive problems. He has developed specific expertise in treating lower testosterone levels. In this interview, Dr. Morgentaler shares his views on current controversies, the treatment plans he uses with his patients, and why he believes experts should reconsider the potential link between testosterone-replacement treatment and prostate cancer.
Symptoms and diagnosisWhat signs and symptoms of low testosterone prompt that the average man to find a doctor?
As a urologist, I have a tendency to see men since they have sexual complaints. The primary hallmark of low testosterone is reduced sexual desire or libido, but another may be erectile dysfunction, and some other man who complains of erectile dysfunction must possess his testosterone level checked. Men may experience different symptoms, like more difficulty achieving an orgasm, less-intense climaxes, a much smaller quantity of fluid out of ejaculation, and a feeling of numbness in the penis when they see or experience something which would normally be arousing.
The more of these symptoms you will find, the more likely it is that a man has low testosterone. Many physicians often discount these"soft symptoms" as a normal part of aging, but they're often treatable and reversible by decreasing testosterone levels.
Aren't those the same symptoms that guys have when they are treated for benign prostatic hyperplasia, or BPH?
Not exactly. There are a number of medications which may lessen sex drive, including the BPH medication finasteride (Proscar) and dutasteride (Avodart). Those drugs may also decrease the amount of the ejaculatory fluid, no wonder. However a reduction in orgasm intensity usually doesn't go along with therapy for BPH. Erectile dysfunction does not ordinarily go along with it either, though certainly if a person has less sex drive or less attention, it is more of a challenge to get a good erection.
How can you decide whether a man is a candidate for testosterone-replacement therapy?
There are just two ways we determine whether somebody has low testosterone. One is a blood test and the other is by characteristic signs and symptoms, and the correlation between these two approaches is far from ideal. Generally men with the lowest testosterone have the most symptoms and men with highest testosterone have the least. But there are some men who have reduced levels of testosterone in their blood and have no signs.
Looking at the biochemical numbers, The Endocrine Society* considers low testosterone to be a total testosterone level of less than 300 ng/dl, and I think that is a sensible guide. However, no one really agrees on a few. It is similar to diabetes, in which if your fasting sugar is over a certain level, they will say,"Okay, you've got it." With testosterone, that break point isn't quite as clear.
*Note: The Endocrine Society publishes clinical practice guidelines with recommendations for who should and shouldn't receive testosterone therapy. For a complete copy of the guidelines, log Discover More on to www.endo-society.org. |
Is total testosterone the right thing to be measuring? Or should we be measuring something else?
Well, this is another area of confusion and good discussion, but I do not think that it's as confusing as it is apparently in the literature. When most doctors learned about testosterone in medical school, they learned about total testosterone, or all of the testosterone in the human body. However, about half of their testosterone that is circulating in the bloodstream is not available to the cells. It is closely bound to a copyright molecule known as sex hormone--binding globulin, which we abbreviate as SHBG.
The available portion of overall testosterone is known as free testosterone, and it's readily available to the cells. Though it's only a small fraction of this overall, the free testosterone level is a pretty good indicator of low testosterone. It's not ideal, but the significance is greater than with total testosterone.
Endocrine Society recommendations summarizedThis professional organization recommends testosterone treatment for men who have Therapy Isn't Suggested for men who have
|