A Harvard Specialist shares his Ideas on testosterone-replacement Treatment
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, large muscles, and facial and body hair, distinguishing 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. It also fosters the creation of red blood cells, boosts mood, and aids cognition.
Over time, the "machinery" which produces 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 sex drive and sense of energy, 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" significance low functioning and"gonadism" speaking to the testicles). Yet it's an underdiagnosed problem, with just about 5% of those affected undergoing therapy.
Various studies have shown that testosterone-replacement therapy can offer a vast range of advantages for men with hypogonadism, including enhanced 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 diseases 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 he thinks specialists should rethink the possible connection between testosterone-replacement therapy and prostate cancer.
Symptoms and diagnosisWhat symptoms and signs of low testosterone prompt the typical man to see a physician?
As a urologist, I tend to observe guys because they have sexual complaints. The main hallmark of low testosterone is low sexual desire or libido, but another can be erectile dysfunction, and some other man who complains of erectile dysfunction must possess his testosterone level checked. Men may experience different symptoms, such as more difficulty achieving an orgasm, less-intense climaxes, a smaller quantity of fluid from 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 tend to dismiss those"soft symptoms" as a normal part of aging, however, they are often treatable and reversible by normalizing testosterone levels.
Are not those the very same symptoms that men have when they're treated for benign prostatic hyperplasia, or BPH?
Not precisely. There are quite a few drugs that may reduce libido, including the BPH drugs finasteride (Proscar) and dutasteride (Avodart). Those drugs may also reduce the amount of the ejaculatory fluid, no question. But a decrease in orgasm intensity normally does not go along with treatment for BPH. Erectile dysfunction does not ordinarily go together with it , though surely if a person has less sex drive or less interest, it's more of a challenge to have a fantastic erection.
How can you determine whether or not 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 symptoms and signs, and the correlation between those two methods is far from ideal. Normally guys with the lowest testosterone have the most symptoms and guys with maximum testosterone possess the least. However, there are a number of guys 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's a reasonable guide. But no one quite agrees on a number. It's not like diabetes, where if your fasting glucose is above a certain level, they'll say,"Okay, you've got it." With testosterone, that break point is not quite as clear.
| *Note: The Endocrine Society recommends clinical practice guidelines with recommendations for who should and should not receive testosterone therapy. For a complete copy of the guidelines, log on site to www.endo-society.org. |
Is total testosterone the right thing to be measuring? Or if we are measuring something else?
This is just another area of confusion and good discussion, but I don't think it's as confusing as it is apparently from the literature. When most doctors 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's circulating in the blood isn't readily available to cells. It is closely bound to a carrier molecule known as sex hormone--binding globulin, which we abbreviate as SHBG.
The biologically available part of total testosterone is called free testosterone, and it is readily available to cells. Though it's only a small fraction of this overall, the free testosterone level is a pretty good indicator of low testosterone. It is not ideal, but the correlation is greater than with testosterone.
This professional organization recommends testosterone treatment for men who have
Therapy Isn't recommended for men who have
- Breast or prostate cancer
- a nodule on the prostate which can be felt during a DRE
- that a PSA higher than 3 ng/ml without further evaluation
- that a hematocrit greater than 50% or thick, viscous blood
- untreated obstructive sleep apnea
- severe lower urinary tract symptoms
- class III or IV heart article source failure.
Do time daily, diet, or other elements affect testosterone levels?
For many years, the recommendation has been to get a testosterone value early in the morning since levels begin to drop after 10 or even 11 a.m.. However, the data behind this recommendation were drawn from healthy young men. Two recent studies showed little change in blood glucose levels in men 40 and older within the course of the day. One reported no change in average testosterone till after 2 p.m. Between 6 and 2 p.m., it went down by 13%, a small amount, 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 5 or 6 p.m.
There are a number of very interesting findings about dietary supplements. For instance, 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 create any recommendations that are clear.
FormulationsExogenous vs. endogenous testosterone
Within this guide, testosterone-replacement therapy refers to the treatment of hypogonadism with adrenal gland -- testosterone that's manufactured outside the body. Based on the formula, treatment can lead to skin irritation, breast enlargement and tenderness, sleep apnea, acne, decreased sperm count, increased red blood cell count, along with other side effects.
Preliminary studies have shown that clomiphene citrate (Clomid), a drug generally prescribed to stimulate ovulation in women struggling with infertility, may boost the production of natural testosterone, also known as endogenous testosterone, in men. Within four to six weeks, each one of the men had increased levels of testosteronenone reported some side effects during the entire year they had been followed.
Because clomiphene citrate is not accepted by the FDA for use in men, little information exists regarding the long-term ramifications of taking it (including the probability of developing prostate cancer) or if it is more effective at boosting testosterone compared to exogenous formulations. But unlike adrenal gland, clomiphene citrate maintains -- and possibly enhances -- sperm production. This makes medication like clomiphene citrate one of only a few choices for men with low testosterone that wish to father children.
What kinds of testosterone-replacement treatment can be found? *
The oldest form is an injection, which we use because it is cheap and since we reliably get good testosterone levels in almost everybody. The drawback is that a person needs to come in every few weeks to get a shot. A roller-coaster effect can also happen as blood glucose levels peak and return to research. [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 quite large rate of skin irritation. In 1 study, as many as 40 percent of people that used the patch developed a reddish area on their skin. That restricts its usage.
The most widely used testosterone preparation from the United States -- and also the one I begin almost everyone off -- is a topical gel. The gel comes from tiny tubes or in a special dispenser, and you rub it on your shoulders or upper arms once a day. Based on my experience, it tends to be absorbed to good levels in about 80% to 85% of men, but that leaves a substantial number who don't absorb enough for it to have a positive effect. [For specifics on various formulations, see table below.]
Are there any drawbacks to using gels? How much time does it require them to get the job done?
Men who begin using the implants need to return in to have their own testosterone levels measured again to be certain they are absorbing the right amount. Our goal is that 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 quickly, within a few doses. I usually measure it after two weeks, even although symptoms may not alter for a month or two.