A Harvard expert shares his thoughts on testosterone-replacement Treatment
An interview with Abraham Morgentaler, M.D.
It could be said that testosterone is what makes men, men. It gives them their characteristic deep voices, large muscles, and body and facial hair, differentiating them from girls. It stimulates the development of the genitals , plays a role in sperm production, fuels libido, and contributes to normal erections. It also boosts the creation of red blood cells, boosts mood, and assists cognition.
As time passes, the "machinery" that produces testosterone slowly becomes less powerful, and testosterone levels begin to drop, by about 1% a year, beginning in the 40s. As men get in their 50s, 60s, and beyond, they might begin to have symptoms and signs of low testosterone like reduced sex drive and sense of vitality, erectile dysfunction, decreased energy, decreased muscle mass and bone density, and nausea. Taken together, these symptoms and signs are often referred to as hypogonadism ("hypo" meaning low working and"gonadism" speaking to the testicles). Yet it's an underdiagnosed problem, with only about 5 percent of these affected undergoing therapy.
But little consensus exists on what constitutes low testosterone, when testosterone supplementation makes sense, or what risks patients face. 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 diseases and male sexual and reproductive difficulties. He's developed particular expertise in treating lower testosterone levels. In this interview, Dr. Morgentaler shares his views on current controversies, the treatment strategies he utilizes his own patients, and why he believes experts should reconsider the possible connection between testosterone-replacement therapy and prostate cancer.
Symptoms and diagnosisWhat signs and symptoms of low testosterone prompt that the average person to see a physician?
As a urologist, I tend to see guys because they have sexual complaints. The main hallmark of low testosterone is reduced sexual libido or desire, but another can be erectile dysfunction, and some other man who complains of erectile dysfunction must get his testosterone level checked. Men can experience different symptoms, like more difficulty achieving an orgasm, less-intense climaxes, a lesser amount of fluid out of ejaculation, and a feeling of numbness in the manhood when they see or experience something that would usually be arousing.
The more of the symptoms there are, the more probable it is that a man has low testosterone. Many physicians tend to discount those"soft symptoms" as a normal part of aging, but they're often treatable and reversible by normalizing testosterone levels.
Are not those the same symptoms that guys have when they are treated for benign prostatic hyperplasia, or BPH?
Not exactly. There are quite a few drugs that may reduce libido, including the BPH medication finasteride (Proscar) and dutasteride (Avodart). Those drugs may also decrease the amount of the ejaculatory fluid, no wonder. But a decrease in orgasm intensity usually does not go together with therapy for BPH. Erectile dysfunction does not usually go along with it , though certainly if a person has less sex drive or less attention, it's more of a challenge to have a fantastic erection.
How do you determine if or not a person is a candidate for testosterone-replacement therapy?
There are two ways we determine whether somebody has low testosterone. One is a blood test and the other one is by characteristic signs and symptoms, and the correlation between these two methods is far from perfect. Generally guys with the lowest testosterone have the most symptoms and guys with maximum 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* believes low testosterone for a entire testosterone level of less than 300 ng/dl, and I think that's a reasonable guide. But no one quite agrees on a number. It's not like diabetes, where 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 apparent.
| *Notice: The Endocrine Society recommends clinical practice guidelines with recommendations for who should read this article and should not receive testosterone therapy. For a complete copy of the guidelines, log on to www.endo-society.org. |
Is complete testosterone the ideal point to be measuring? Or if we are measuring something different?
This is just another area of confusion and good discussion, but I do not think that it's as confusing as it is apparently from the literature. When most physicians learned about testosterone in medical school, they heard about overall testosterone, or all of the testosterone in the body. But about half of the testosterone that is circulating in the bloodstream is not available to the cells.
The available part of total testosterone is known as free testosterone, and it is readily available to cells. Nearly every laboratory has a blood test to measure free testosterone. Though it's just a small fraction of the overall, the free testosterone level is a fairly good indicator of reduced testosterone. It's not perfect, but the correlation is greater than with testosterone.
Endocrine Society recommendations outlinedThis professional organization urges testosterone therapy for men who have both Therapy Isn't Suggested for men who have
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Do time of day, diet, or other elements affect testosterone levels?
For years, the recommendation was to get a testosterone value early in the morning since levels start to drop after 10 or even 11 a.m.. But the information behind that recommendation were drawn from healthy young men. Two recent studies demonstrated little change in blood testosterone levels in men 40 and mature over the course of this day. One reported no change in average testosterone till after 2 p.m. Between 6 and 2 p.m., it went down by 13 percent, a modest sum, and probably not enough to affect diagnosis. Most guidelines nevertheless say it's important to perform the test in the morning, however for men 40 and above, it likely doesn't matter much, provided that they get their blood drawn before 6 or 5 p.m.
There are some rather interesting findings about diet. By way of instance, it appears that those who have a diet low in protein have lower testosterone levels than males who eat more protein. But diet hasn't been researched thoroughly enough to make any recommendations that are clear.
Within the following article, testosterone-replacement treatment refers to the treatment of hypogonadism with exogenous testosterone -- testosterone that's produced outside the body. Depending upon the formula, treatment can cause skin irritation, breast tenderness and enlargement, sleep apnea, acne, reduced sperm count, increased red blood cell count, along with other side effects.
In a recent prospective study, 36 hypogonadal men took a daily dose of clomiphene citrate for at least three months. Within four to six months, each one of the men had increased levels of testosteronenone reported some side effects during the year they were followed.
Since clomiphene citrate isn't accepted by the FDA for use in men, little information exists about the long-term ramifications of carrying it (including the risk of developing prostate cancer) or if it's more capable of boosting testosterone compared to exogenous formulas. But unlike adrenal gland, clomiphene citrate maintains -- and potentially enhances -- sperm production. That makes drugs like clomiphene citrate one of only a few choices for men with low testosterone who want to father children.
What forms of testosterone-replacement treatment can be found? *
The earliest form is the injection, which we use because it's inexpensive and because we reliably get good testosterone levels in nearly everybody. The disadvantage is that a person should come in every couple of weeks to find a shot. A roller-coaster effect may also happen as blood glucose levels peak and return to baseline.
Topical therapies help maintain a more uniform level of blood glucose. The first kind of topical treatment has been a patch, but it has a very high rate of skin irritation. In one study, as many as 40% of people that used the patch developed a reddish area in their skin. That restricts its use.
The most commonly used testosterone preparation in the United States -- and the one I begin almost everyone off -- is a topical gel. According to my experience, it has a tendency to be consumed to good levels in about 80% to 85% of guys, but leaves a substantial number who don't consume sufficient for this to have a positive effect. [For details on several different formulations, see table ]
Are there any drawbacks to using gels? How much time does it require them to work?
Men who start using the gels have to return in to have their own testosterone levels measured again to make sure they are absorbing the proper amount. Our target is the mid to upper assortment of normal, which generally means around 500 to 600 ng/dl. The concentration of testosterone in the blood really goes up quite fast, within several doses. I normally measure it after two weeks, even although symptoms may not change for a month or two.