A Harvard Specialist shares his Ideas on testosterone-replacement therapy
It might be said that testosterone is the thing that makes men, guys. It gives them their characteristic deep voices, big muscles, and facial and body hair, differentiating them from women. It stimulates the development of the genitals at puberty, plays a role in sperm production, fuels libido, and leads to regular erections. It also boosts the production of red blood cells, boosts mood, and aids cognition.
As time passes, the testicular"machinery" which produces testosterone gradually becomes less powerful, and testosterone levels begin to fall, by approximately 1 percent a year, starting in the 40s. As guys get into their 50s, 60s, and beyond, they might begin to have signs and symptoms of low testosterone like reduced sex drive and sense of vitality, erectile dysfunction, diminished 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). Yet it is an underdiagnosed problem, with just about 5 percent 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 ailments and male reproductive and sexual difficulties. He's developed specific experience in treating low testosterone levels. In this interview, Dr. Morgentaler shares his views on current controversies, the treatment strategies he utilizes his patients, and why he thinks specialists should rethink the potential connection between testosterone-replacement therapy and prostate cancer.
Symptoms and diagnosisWhat signs and symptoms of low testosterone prompt the average man to see a physician?
As a urologist, I have a tendency to observe guys since they have sexual complaints. The main hallmark of reduced testosterone is reduced sexual libido or desire, but another may be erectile dysfunction, and some other guy who complains of erectile dysfunction must possess his testosterone level checked. Men can experience different symptoms, like more trouble achieving an orgasm, less-intense climaxes, a much lesser quantity of fluid out of ejaculation, and a sense of numbness in the manhood when they see or experience something which would usually be arousing.
The more of the symptoms you will find, the more probable it is that a man has low testosterone. Many physicians often discount those"soft symptoms" as a normal part of aging, but they are often treatable and reversible by normalizing testosterone levels.
Aren't those the same symptoms that men have when they're treated for benign prostatic hyperplasia, or BPH?
Not precisely. There are quite a few medications which may reduce libido, including the BPH drugs finasteride (Proscar) and dutasteride (Avodart). Those drugs can also decrease the quantity 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 along with it either, though certainly if a person has less sex drive or less attention, it is more of a challenge to get a good erection.
How can you decide whether a man is a candidate for testosterone-replacement treatment?
There are just two ways that 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 those two methods is far from perfect. Normally guys with the lowest testosterone have the most symptoms and men with highest testosterone possess the least. However, there are some guys who have reduced levels of testosterone in their blood and have no symptoms.
Looking purely at the biochemical amounts, The Endocrine Society* believes low testosterone to be a entire testosterone level of less than 300 ng/dl, and I believe that's a reasonable guide. However, no one really agrees on a number. It is similar to diabetes, where if your fasting sugar is over 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 should not receive testosterone therapy. For a imp source complete copy of these guidelines, log on to www.endo-society.org. |
Is complete testosterone the right point to be measuring? Or if we are measuring something else?
This is another area of confusion and good discussion, but I don't think that 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 the testosterone in the human body. But about half of the testosterone that is circulating in the bloodstream isn't available to cells.
The available portion of total testosterone is known as free testosterone, and it's readily available to cells. Nearly every laboratory has a blood test to measure free testosterone. Even though it's just a small portion of the overall, the free testosterone level is a pretty good indicator of reduced testosterone. It's not ideal, but the correlation is greater compared to total testosterone.
This professional organization recommends testosterone treatment for men who have both
- Reduced levels of testosterone in the blood (less than 300 ng/dl)
- symptoms of low testosterone.
Therapy is not Suggested for men who have
- Breast or prostate cancer
- a nodule on the prostate that may be felt during a DRE
- a PSA higher than 3 ng/ml without additional evaluation
- that a hematocrit greater than 50% or thick, viscous blood
- untreated obstructive sleep apnea
- severe lower urinary tract infections
- class III or IV heart failure.
Do time of day, diet, or other elements affect testosterone levels?
For many 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 showed little change in blood glucose levels in men 40 and older over the course of this day. One reported no change in average testosterone till after 2 Between 6 and 2 p.m., it went down by 13%, a small sum, and probably not enough to affect identification. Most guidelines still say it is important to perform the test in the morning, however for men 40 and over, it likely doesn't matter much, as long as they obtain their blood drawn before 5 or 6 p.m.
There are some rather interesting findings about dietary supplements. For instance, it seems that individuals who have a diet low in protein have lower testosterone levels than males who eat more protein. But diet hasn't been studied thoroughly enough to create any clear recommendations.
Within the following guide, testosterone-replacement treatment refers to the treatment of hypogonadism with exogenous testosterone -- testosterone that is produced outside the body. Based upon the formula, treatment can cause skin irritation, breast tenderness and enlargement, sleep apnea, acne, decreased sperm count, increased red blood cell count, and other side effects.
Preliminary research has shown that clomiphene citrate (Clomid), a drug generally prescribed to stimulate ovulation in women struggling with infertility, may boost the creation of natural testosterone, termed endogenous testosterone, 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 months, each one the men had heightened levels of testosterone; none reported any side effects throughout the entire year they had been followed.
Since clomiphene citrate isn't accepted by the FDA for use in males, little information exists regarding the long-term ramifications of taking it (including the risk of developing prostate cancer) or whether it is more effective at boosting testosterone than exogenous formulations. But unlike exogenous testosterone, clomiphene citrate preserves -- and possibly enriches -- sperm production. This makes medication such as clomiphene citrate one of just a few options for men with low testosterone that want to father children.
FormulationsWhat forms of testosterone-replacement therapy are available? *
The oldest form is an injection, which we use since it's inexpensive and because we reliably become fantastic testosterone levels in almost everybody. The drawback is that a man needs to come in every few weeks to get a shot. A roller-coaster effect may also happen as blood glucose levels peak and then return to baseline.
Topical therapies help preserve a more uniform amount of blood glucose. The first form of topical therapy has been a patch, but it has a quite large rate of skin irritation. In one study, as many as 40% of men who 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 start almost everyone off -- is a topical gel. There are just two brands: AndroGel and Testim. The gel comes from tiny tubes or within a special dispenser, and you rub it on your shoulders or upper arms once a day. Based on my experience, it tends to be consumed to great degrees in about 80% to 85% of men, but leaves a substantial number who don't absorb sufficient for it to have a positive impact. [For details on various formulations, see table ]
Are there any downsides to using gels? How long does it require them to get the job done?
Men who start using the gels have to come back in to have their own testosterone levels measured again to be sure they are absorbing the proper amount. Our goal is that the mid to upper range of normal, which usually means approximately 500 to 600 ng/dl. The concentration of testosterone in the blood actually goes up quite fast, within a few doses. I normally measure it after two weeks, although symptoms may not change for a month or two.