A Harvard Specialist shares his Ideas on testosterone-replacement therapy
It might be said that testosterone is the thing that makes men, men. 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 contributes to regular erections. It also boosts the creation of red blood cells, boosts mood, and aids cognition.
As time passes, the "machinery" which produces testosterone slowly becomes less effective, and testosterone levels begin to drop, by about 1 percent per year, beginning in the 40s. As guys get in their 50s, 60s, and beyond, they may begin to have signs and symptoms of low testosterone such as reduced libido and sense of vitality, erectile dysfunction, diminished energy, decreased muscle mass and bone density, and anemia. Taken together, these signs and symptoms are often referred to as hypogonadism ("hypo" meaning 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 is an underdiagnosed issue, with just about 5% of those affected undergoing therapy.
But little consensus exists on what constitutes low testosterone, when testosterone supplementation makes sense, or what risks patients face.
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 sexual and reproductive 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 treatment and prostate cancer.
Symptoms and diagnosisWhat signs and symptoms of low testosterone prompt the average man to find a physician?
As a urologist, I have a tendency to observe guys since they have sexual complaints. The primary hallmark of low testosterone is low sexual desire or libido, but another can be erectile dysfunction, and any man who complains of erectile dysfunction should get his testosterone level checked. Men may experience other symptoms, such as more difficulty achieving an orgasm, less-intense orgasms, a smaller amount of fluid from ejaculation, and a feeling of numbness in the penis when they see or experience something that would usually be arousing.
The more of these 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, however, they're often treatable and reversible by decreasing testosterone levels.
Aren't those the same symptoms that men have when they're treated for benign prostatic hyperplasia, or BPH?
Not exactly. There are a number of medications which may reduce libido, such as the BPH medication finasteride (Proscar) and dutasteride (Avodart). Those drugs may also decrease the amount of the ejaculatory fluid, no question. But a decrease in orgasm intensity usually 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 attention, it is more of a challenge to get a good erection.
How do you decide if or not a man is a candidate for testosterone-replacement therapy?
There are two ways we determine whether somebody has reduced testosterone. One is a blood test and the other one is by characteristic signs and symptoms, and the correlation between these two methods is far from perfect. Normally guys with the lowest testosterone have the most symptoms and guys with highest testosterone have the least. However, there are a number of men who have low levels of testosterone in their blood and have no signs.
Looking at the biochemical amounts, The Endocrine Society* believes low testosterone to be a total testosterone level of less than 300 ng/dl, and I believe that is a reasonable guide. But no one really agrees on a few. It's not like diabetes, in which if your fasting sugar is above a certain level, they will 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 complete copy of these instructions, log 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 good discussion, but I don't think that it's as confusing as it is apparently in the literature. When most physicians learned about testosterone in medical school, they learned about total testosterone, or all of the testosterone in the body. However, about half of the testosterone that is circulating in the bloodstream isn't readily available to the cells.
The available portion of total testosterone is called free testosterone, and it is readily available to the cells. Nearly every lab has a blood test to measure free testosterone. Though it's only a little portion of the overall, the free testosterone level is a fairly good indicator of low testosterone. It is not perfect, but the significance is greater than with testosterone.
This professional organization urges testosterone therapy 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
- that a PSA greater 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 symptoms
- class III or IV heart failure. visit site
Do time daily, diet, or other factors influence testosterone levels?
For 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.. But the information 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 this day. One reported no change in average testosterone till after 2 Between 6 and 2 p.m., it went down by 13%, a modest sum, and probably insufficient to influence identification. Most guidelines nevertheless say it's important to do the evaluation in the morning, however for men 40 and over, it probably doesn't matter much, provided that they obtain their blood drawn before 6 or 5 p.m.
There are some very interesting findings about dietary supplements. By way of instance, it appears 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 make any recommendations that are clear.
Exogenous vs. endogenous testosterone
Within the following guide, testosterone-replacement therapy refers to the treatment of hypogonadism with exogenous testosterone -- testosterone that is produced outside the body. Based upon the formula, therapy can lead to skin irritation, breast enlargement and tenderness, sleep apnea, acne, reduced sperm count, increased red blood cell count, and other side effects.
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, all of the men had increased levels of testosteronenone reported any side effects during the year they were followed.
Because clomiphene citrate is not approved by the FDA for use in men, little information exists about the long-term effects of taking it (such as the probability of developing prostate cancer) or if it's more capable of boosting testosterone compared to exogenous formulas. But unlike adrenal gland, clomiphene citrate maintains -- and potentially enhances -- sperm production. That makes drugs like clomiphene citrate one of only a few choices for men with low testosterone that wish to father children.
What kinds of testosterone-replacement therapy are available? *
The oldest form is an injection, which we still use since it is cheap and since we reliably get good testosterone levels in almost 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 preserve a more uniform amount of blood testosterone. The first form of topical therapy was 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 red area in their skin. That restricts its usage.
The most widely used testosterone preparation in the United States -- and the one I begin almost everyone off -- is a topical gel. Based on my experience, it has a tendency to be absorbed to good degrees in about 80% to 85 percent of men, but leaves a significant number who don't consume sufficient for it to have a favorable impact. [For specifics on several different formulations, see table ]
Are there any drawbacks to using dyes? How much time does it take for them to get the job done?
Men who begin using the gels have to return in to have their testosterone levels measured again to make certain they're absorbing the proper amount. Our target is that the mid to upper range of normal, which generally means around 500 to 600 ng/dl. The concentration of testosterone in blood actually goes up quite fast, within a few doses. I normally measure it after two weeks, even though symptoms may not change for a month or two.