A Harvard Specialist shares his thoughts on testosterone-replacement Treatment
A meeting with Abraham Morgentaler, M.D.
It could be said that testosterone is what makes guys, men. It gives them their characteristic deep voices, big muscles, and facial and body hair, differentiating them from girls. It stimulates the development of the genitals at puberty, plays a role in sperm production, fuels libido, and contributes to normal erections. Additionally, it boosts the creation of red blood cells, boosts mood, and aids cognition.
Over time, the testicular"machinery" which produces testosterone gradually becomes less powerful, and testosterone levels start to fall, by approximately 1% per year, starting in the 40s. As guys get in their 50s, 60s, and beyond, they might start to have symptoms and signs of low testosterone such as reduced sex drive and sense of energy, erectile dysfunction, diminished energy, reduced muscle mass and bone density, and anemia. Taken together, these symptoms and signs are often referred to as hypogonadism ("hypo" significance low working and"gonadism" referring 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 only about 5% of those 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 diseases and male reproductive and sexual difficulties. He's developed particular expertise in treating low testosterone levels. In this interview, Dr. Morgentaler shares his perspectives on current controversies, the treatment plans he uses with his own patients, and he thinks experts should reconsider the possible link between testosterone-replacement treatment and prostate cancer.
Symptoms look at these guys and diagnosisWhat symptoms and signs of low testosterone prompt that the typical person to find a physician?
As a urologist, I tend to see guys since they have sexual complaints. The primary hallmark of reduced testosterone is reduced sexual libido or desire, but another can be erectile dysfunction, and some other guy who complains of erectile dysfunction should get his testosterone level checked. Men can experience other symptoms, such as more trouble achieving an orgasm, less-intense orgasms, a much lesser amount of fluid out of ejaculation, and a feeling 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 probable it is that a man has low testosterone. Many physicians often discount these"soft symptoms" as a normal part of aging, but they are often treatable and reversible by decreasing 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 quite a few drugs that may reduce libido, such as the BPH medication finasteride (Proscar) and dutasteride (Avodart). Those drugs may also reduce the quantity of the ejaculatory fluid, no wonder. However a decrease in orgasm intensity usually doesn't go together with treatment for BPH. Erectile dysfunction does not usually go along with it , though surely if somebody has less sex drive or less interest, it is more of a challenge to get a good erection.
How can you determine if or not a person is a candidate for testosterone-replacement treatment?
There are two ways that we determine whether someone has reduced testosterone. One is a blood test and the other one is by characteristic symptoms and signs, and the correlation between those two approaches is far from perfect. Generally men with the lowest testosterone have the most symptoms and guys with highest testosterone have the least. However, there are some men who have reduced levels of testosterone in their blood and have no symptoms.
Looking at the biochemical numbers, The Endocrine Society* considers low testosterone for a total testosterone level of less than 300 ng/dl, and I believe that's a sensible guide. But no one quite agrees on a number. It's not like diabetes, in which if your fasting glucose is above a certain level, they'll say,"Okay, you've got it." With testosterone, that break point isn't quite as clear.
| *Note: The Endocrine Society recommends clinical practice guidelines with recommendations for who should and shouldn't receive testosterone therapy. See"Endocrine Society recommendations summarized." |
Is total testosterone the ideal point to be measuring? Or if we are measuring something different?
This is just another area of confusion and great debate, but I do not think it's as confusing as it appears to be from the literature. When most doctors learned about testosterone in medical school, they heard about total testosterone, or all the testosterone in the body. However, about half of the testosterone that is circulating in the bloodstream isn't available to cells. It's tightly bound to a carrier molecule called sex hormone--binding globulin, which we abbreviate as SHBG.
The biologically available portion of overall testosterone is called free testosterone, and it's readily available to the cells. Nearly every lab has a blood test to measure free testosterone. Even though it's just a little portion of the overall, the free testosterone level is a fairly good indicator of reduced testosterone. It is not perfect, but the correlation is greater than with testosterone.
Endocrine Society recommendations outlinedThis professional organization recommends testosterone treatment for men who have both Therapy Isn't recommended for men who have
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Do time daily, diet, or other factors influence testosterone levels?
For many years, the recommendation has been to receive a testosterone value early in the morning because levels start to fall after 10 or 11 a.m.. However, the data behind that recommendation were attracted to healthy young men. Two recent studies showed little change in blood glucose levels in men 40 and mature within the course of the day. One reported no change in typical testosterone until after 2 Between 2 and 6 p.m., it went down by 13 percent, a small amount, and probably insufficient to influence diagnosis. Most guidelines nevertheless say it is important to do the evaluation in the morning, however for men 40 and above, it likely does not matter much, as long as they get their blood drawn before 5 or 6 p.m.
There are some rather interesting findings about diet. By way of example, it appears that those who have a diet low in protein have lower testosterone levels than males who consume more protein. But diet has not been studied thoroughly enough to make any clear recommendations.
Exogenous vs. endogenous testosteroneIn this guide, testosterone-replacement treatment refers to the treatment of hypogonadism with exogenous testosterone -- testosterone that's manufactured outside the body. Depending upon the formula, treatment can lead to skin irritation, breast enlargement and tenderness, sleep apnea, acne, decreased sperm count, increased red blood cell count, and additional side effects. Preliminary research has shown that clomiphene citrate (Clomid), a drug generally prescribed to stimulate ovulation in women struggling with infertility, may foster the creation of natural testosterone, known as nitric oxide, in men. In a recent prospective study, 36 hypogonadal men took a daily dose of clomiphene citrate for at least three months. Within four to six weeks, each one of the men had heightened levels of testosterone; none reported any side effects during the entire year they were followed. Because clomiphene citrate isn't approved by the FDA for use in males, little information exists about the long-term ramifications of taking it (such as the risk of developing prostate cancer) or whether it is more capable of boosting testosterone than exogenous formulas. But unlike exogenous testosterone, clomiphene citrate maintains -- and possibly enhances -- sperm production. This makes medication such as clomiphene citrate one of only a few options for men with low testosterone who want to father children. |
What kinds of testosterone-replacement treatment are available? *
The earliest form is an injection, which we use because it is inexpensive and since we faithfully get fantastic testosterone levels in almost everybody. The drawback is that a man needs to come in every couple of weeks to find a shot. A roller-coaster effect may also happen as blood glucose levels peak and then return to baseline. [Watch"Exogenous vs. endogenous testosterone," above.]
Topical treatments help maintain a more uniform level of blood testosterone. The first form of topical therapy has been a patch, but it has a very large rate of skin irritation. In 1 study, as many as 40% of men who used the patch developed a reddish area in their skin. That restricts its usage.
The most commonly used testosterone preparation from the United States -- and the one I start almost everyone off -- is a topical gel. Based on my experience, it tends to be consumed to great levels in about 80% to 85% of men, but leaves a significant number who do not absorb enough for it to have a positive impact. [For specifics on various formulations, see table ]
Are there any drawbacks to using gels? How much time does it require them to get the job done?
Men who start using the implants need to return in to have their testosterone levels measured again to make sure they are absorbing the right quantity. Our goal is the mid to upper range of normal, which usually means around 500 to 600 ng/dl. The concentration of testosterone in blood actually goes up quite fast, in just a few doses. I usually measure it after 2 weeks, although symptoms may not change for a month or two.