A Harvard expert shares his Ideas on testosterone-replacement Treatment
A meeting with Abraham Morgentaler, M.D.
It might be said that testosterone is what makes guys, men. It gives them their characteristic deep voices, large muscles, and facial and body hair, differentiating them from girls. It stimulates the growth of the genitals at puberty, plays a role in sperm production, fuels libido, and leads to regular erections. It also boosts the creation of red blood cells, boosts mood, and aids cognition.
Over time, the "machinery" which makes testosterone gradually becomes less powerful, and testosterone levels start to fall, by approximately 1% a year, starting in the 40s. As men get into their 50s, 60s, and beyond, they might start to have signs and symptoms of low testosterone like lower libido and sense of vitality, erectile dysfunction, decreased energy, decreased muscle mass and bone density, and anemia. Taken together, these symptoms and signs are often referred to as hypogonadism ("hypo" meaning 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 those affected undergoing therapy.
Studies have revealed that testosterone-replacement therapy may provide a wide selection of benefits for men with hypogonadism, such as improved libido, mood, cognition, muscle mass, bone density, and red blood cell production. 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 ailments and male reproductive and sexual difficulties. 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 typical person to see a physician?
As a urologist, I tend to observe men since 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 guy who complains of erectile dysfunction should possess his testosterone level checked. Men can experience other symptoms, like more trouble achieving an orgasm, less-intense orgasms, a lesser amount of fluid from ejaculation, and a sense of numbness in the manhood when they see or experience something that would normally be arousing.
The more of the symptoms there are, 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 men have when they are treated for benign prostatic hyperplasia, or BPH?
Not exactly. There are quite a few drugs that may reduce libido, such as the BPH medication finasteride (Proscar) and dutasteride (Avodart). Those drugs can also decrease the amount of the ejaculatory fluid, no wonder. However a decrease in orgasm intensity usually does not go along with therapy for BPH. Erectile dysfunction does not ordinarily go together with it , though certainly if a person has less sex drive or less attention, it is more of a struggle to get a good erection.
How do you determine if or not a person is a candidate for testosterone-replacement treatment?
There are two ways that we determine whether somebody has low testosterone. One is a blood test and the other is by characteristic symptoms and signs, and the correlation between these two approaches is far from ideal. Normally guys with the lowest testosterone have the most symptoms and men with maximum testosterone possess the least. However, there are a number of guys who have low levels of testosterone in their blood and have no symptoms.
Looking purely 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's a reasonable guide. But no one quite agrees on a number. It's not like 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 apparent.
| *Notice: The Endocrine Society recommends clinical practice guidelines with recommendations for who should and should not review receive testosterone see here treatment. For a complete copy of these instructions, log on to www.endo-society.org. Is total testosterone the right thing to be measuring? Or should we be 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 the testosterone in the body. But about half of the testosterone that is circulating in the blood is not available to the cells. It's closely bound to a carrier 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. Even though it's only a small portion of this total, the free testosterone level is a pretty good indicator of reduced testosterone. It is not perfect, but the correlation is greater compared to testosterone.
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 begin to drop after 10 or even 11 a.m.. But the data behind this recommendation were drawn from healthy young men. Two recent studies demonstrated little change in blood glucose levels in men 40 and older within the course of the day. One reported no change in typical testosterone until after 2 p.m. Between 6 and 2 p.m., it went down by 13%, a small amount, and probably insufficient to influence identification. Most guidelines nevertheless say it's important to perform the test in the morning, however for men 40 and over, it probably does not matter much, as long as they obtain their blood drawn before 6 or 5 p.m. There are some rather interesting findings about diet. By way of example, it seems that individuals that have a diet low in protein have lower testosterone levels than men who eat more protein. But diet has not been studied thoroughly enough to create any recommendations that are clear.
What kinds of testosterone-replacement treatment can be found? * The oldest form is an injection, which we still use since it's cheap and since we faithfully get good testosterone levels in nearly everybody. The drawback is that a person should come in every few weeks to get a shot. A roller-coaster effect can also occur as blood glucose levels peak and return to baseline. Topical treatments help maintain a more uniform level of blood glucose. The first kind of topical treatment has been a patch, but it has a quite large rate of skin irritation. In 1 study, as many as 40% of men who used the patch developed a red area on their skin. That limits its use. The most commonly used testosterone preparation in the United States -- and the one I start almost everyone off with -- is a topical gel. There are just two brands: AndroGel and Testim. According to my experience, it has a tendency to be consumed to great degrees in about 80% to 85 percent of men, but leaves a substantial number who don't absorb enough for it to have a positive effect. [For specifics on various formulations, see table ] Are there any downsides to using dyes? How much time does it take for them to work? Men who start using the gels have to come back in to have their testosterone levels measured again to make sure they are absorbing the proper quantity. Our goal is that the mid to upper range of normal, which usually means around 500 to 600 ng/dl. The concentration of testosterone in the blood actually goes up quite fast, in just several doses. I normally measure it after two weeks, though symptoms may not change for a month or two. |