A Harvard Specialist shares his thoughts on testosterone-replacement Treatment
An interview with Abraham Morgentaler, M.D.
It could be said that testosterone is what makes guys, guys. It gives them their characteristic deep voices, big 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 leads to normal erections. It also fosters the production of red blood cells, boosts mood, and aids cognition.
Over time, the testicular"machinery" that makes testosterone gradually becomes less effective, and testosterone levels start to fall, by approximately 1 percent a year, starting in the 40s. As guys get in their 50s, 60s, and beyond, they might begin to have symptoms and signs of low testosterone like reduced libido and sense of energy, erectile dysfunction, diminished energy, decreased muscle mass and bone density, and nausea. Taken together, these signs and symptoms are often referred to as hypogonadism ("hypo" significance low working and"gonadism" speaking to the testicles). Yet it's an underdiagnosed issue, with only about 5% of those affected receiving treatment.
But little consensus exists about what constitutes low testosterone, when testosterone supplementation makes sense, or what dangers patients face. Much of the current debate focuses on the long-held belief that testosterone may 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 specific expertise in treating low testosterone levels. In this interview, Dr. Morgentaler shares his views on current controversies, the treatment plans he utilizes his own patients, and he believes experts should reconsider the possible link between testosterone-replacement treatment and prostate cancer.
Symptoms and diagnosisWhat symptoms and signs of low testosterone prompt that the average person to find a doctor?
As a urologist, I have a tendency to observe men because they have sexual complaints. The main hallmark of low testosterone is low sexual libido or desire, but another may be erectile dysfunction, and any guy who complains of erectile dysfunction must get his testosterone level checked. Men can experience different symptoms, such as more trouble achieving an orgasm, less-intense orgasms, a much smaller amount of fluid out of ejaculation, and a sense of numbness in the penis when they see or experience something which would normally be arousing.
The more of the symptoms you will find, the more likely it is that a man has low testosterone. Many physicians often dismiss these"soft symptoms" as a normal part of aging, however, they're often treatable and reversible by normalizing testosterone levels.
Are not those the same symptoms that guys have when they're treated for benign prostatic hyperplasia, or BPH?
Not precisely. There are a number of drugs that may reduce libido, including the BPH medication finasteride (Proscar) and dutasteride (Avodart). Those drugs can also reduce the amount of the ejaculatory fluid, no wonder. But a decrease in orgasm intensity usually doesn't go together with treatment for BPH. Erectile dysfunction does not usually go together with it either, though surely if somebody has less sex drive or less attention, it's more of a struggle to get a fantastic erection.
How do you decide whether or not a person is a candidate for testosterone-replacement therapy?
There are just two ways that we determine whether someone has low testosterone. One is a blood test and the other is by characteristic symptoms and signs, and the correlation between those two approaches is far from perfect. Normally guys with the lowest testosterone have the most symptoms and men with maximum testosterone have the least. However, there are some men who have reduced levels of testosterone in their blood and have no symptoms.
Looking purely at the biochemical amounts, The Endocrine Society* considers low testosterone for a entire testosterone level of less than 300 ng/dl, and I think that is a sensible guide. But no one really agrees on a number. It is similar to diabetes, where if your fasting glucose is over a certain level, they'll say,"Okay, you've got it." With testosterone, that break point is not quite as apparent.
| *Note: The Endocrine Society recommends clinical practice guidelines with recommendations for who should and shouldn't receive testosterone this link therapy. For a basics complete copy of the guidelines, log you can try here on to www.endo-society.org. |
Is total testosterone the ideal point to be measuring? Or should we be measuring something different?
This is another area of confusion and great discussion, but I do not think it's as confusing as it appears to be from the literature. When most physicians learned about testosterone in medical school, they learned about overall testosterone, or all of the testosterone in the body. However, about half of their testosterone that's circulating in the bloodstream isn't available to the cells. It is closely bound to a carrier molecule called sex hormone--binding globulin, which we abbreviate as SHBG.
The biologically available portion of overall testosterone is known as free testosterone, and it's readily available to cells. Even though it's only a little fraction of the total, 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 summarizedThis professional organization recommends testosterone treatment for men who have
Therapy is not Suggested for men who've
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Do time of day, diet, or other factors affect testosterone levels?
For years, the recommendation has been to get a testosterone value early in the morning because levels start to drop after 10 or even 11 a.m.. However, the information behind this recommendation were attracted to healthy young men. Two recent studies demonstrated little change in blood testosterone levels in men 40 and older over the course of this day. One reported no change in average testosterone until after 2 p.m. Between 6 and 2 p.m., it went down by 13 percent, a small sum, and probably insufficient to affect diagnosis. Most guidelines still say it's important to do the evaluation in the morning, however for men 40 and over, it probably doesn't matter much, as long as they get their blood drawn before 6 or 5 p.m.
There are a number of rather interesting findings about diet. For example, it seems that those who have a diet low in protein have lower testosterone levels than men who consume more protein. But diet has not been researched thoroughly enough to make any clear recommendations.
Within the following article, testosterone-replacement therapy 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 enlargement and tenderness, sleep apnea, acne, decreased sperm count, increased red blood cell count, and other side effects.
Preliminary studies have proven that clomiphene citrate (Clomid), a drug generally prescribed to stimulate ovulation in women struggling with infertility, can foster the production of natural testosterone, termed nitric oxide, in men. At a recent prospective study, 36 hypogonadal men took a daily dose of clomiphene citrate for at least three months. Within four to six months, all of the men had increased levels of testosterone; none reported any side effects throughout the year they had been followed.
Since clomiphene citrate is not accepted by the FDA for use in males, little information exists about the long-term ramifications of carrying it (including the probability of developing prostate cancer) or whether it's more effective at boosting testosterone compared to exogenous formulas. But unlike exogenous testosterone, clomiphene citrate maintains -- and possibly enriches -- sperm production. That makes drugs such as clomiphene citrate one of only a few options for men with low testosterone who wish to father children.
FormulationsWhat forms of testosterone-replacement treatment are available? *
The earliest form is an injection, which we use since it is cheap and because we faithfully get fantastic testosterone levels in nearly everybody. The drawback is that a man should come in every few weeks to find a shot. A roller-coaster effect can also happen as blood glucose levels peak and then return to research.
Topical treatments help maintain a more uniform amount of blood testosterone. The first form of topical treatment was a patch, but it has a quite large rate of skin irritation. In 1 study, as many as 40% of people that used the patch developed a red area in their skin. That restricts its use.
The most widely used testosterone preparation in the United States -- and the one I begin almost everyone off with -- is a topical gel. There are two brands: AndroGel and Testim. Based on my experience, it tends to be consumed to good degrees in about 80% to 85 percent of men, but that leaves a significant number who don't consume enough for it to have a favorable effect. [For specifics on several different formulations, see table ]
Are there any downsides to using dyes? How long does it take for them to get the job done?
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 quantity. Our goal is the mid to upper assortment of normal, which generally means around 500 to 600 ng/dl. The concentration of testosterone in blood actually goes up quite fast, in just several doses. I usually measure it after two weeks, although symptoms may not change for a month or two.