A Harvard Specialist shares his thoughts on testosterone-replacement therapy
It could be said that testosterone is what makes men, men. It gives them their characteristic deep voices, large muscles, and body and facial hair, differentiating them from girls. It stimulates the development of the genitals , 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 assists cognition.
Over time, the testicular"machinery" that makes testosterone gradually becomes less effective, and testosterone levels start to fall, by about 1% a year, beginning in the 40s. As men get into their 50s, 60s, and beyond, they might begin to have signs and symptoms of low testosterone such as reduced libido and sense of vitality, erectile dysfunction, decreased energy, reduced muscle mass and bone density, and nausea. Taken together, these symptoms and signs are often referred to as hypogonadism ("hypo" significance low working and"gonadism" speaking to the testicles). Yet it is an underdiagnosed problem, with just about 5 percent of these affected undergoing therapy.
But little consensus exists about what constitutes low testosterone, when testosterone supplementation makes sense, or what risks patients face. 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 sexual and reproductive difficulties. He has developed specific experience in treating lower testosterone levels. In this interview, Dr. Morgentaler shares his perspectives on current controversies, the treatment plans he utilizes his own patients, and why he believes specialists should rethink the possible connection between testosterone-replacement treatment and prostate cancer.
Symptoms and diagnosisWhat symptoms and signs of low testosterone prompt the average person to find a doctor?
As a urologist, I have a tendency to observe men since they have sexual complaints. The main hallmark of low testosterone is reduced sexual libido or desire, but another may be erectile dysfunction, and any guy who complains of erectile dysfunction must get his testosterone level checked. Men can experience other symptoms, such as more trouble achieving an orgasm, less-intense climaxes, a lesser quantity of fluid from ejaculation, and a sense 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 tend to discount these"soft symptoms" as a normal part of aging, however, 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 a number of drugs which may lessen sex drive, such as the BPH drugs finasteride (Proscar) and dutasteride (Avodart). Those drugs may also decrease the quantity of the ejaculatory fluid, no wonder. But a decrease in orgasm intensity usually doesn't go along with therapy for BPH. Erectile dysfunction does not ordinarily go together with it either, though certainly if somebody has less sex drive or less attention, it is more of a challenge to have a good erection.
How can you determine if a person is a candidate for testosterone-replacement therapy?
There are just two ways that we determine whether someone has low testosterone. One is a blood test and the other one is by characteristic symptoms and signs, and the correlation between these two methods is far from ideal. Generally guys with the lowest testosterone have the most symptoms and guys with highest testosterone possess the least. But there are a number of men who have reduced levels of testosterone in their blood and have no symptoms.
Looking at the biochemical amounts, The Endocrine Society* considers low testosterone for a entire testosterone level of less than 300 ng/dl, and I believe that's a sensible guide. However, no one really agrees on a number. It is similar to 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 is not quite as clear.
| *Note: The Endocrine Society publishes clinical practice guidelines with recommendations for who should and should here not receive testosterone treatment. look at here For a complete copy of the instructions, log on continue reading this to www.endo-society.org. |
Is total testosterone the ideal point to be measuring? Or should we be measuring something else?
This is another area of confusion and great discussion, but I do not think it's as confusing as it appears to be in the literature. When most physicians learned about testosterone in medical school, they heard about total testosterone, or all the testosterone in the body. However, about half of their testosterone that is circulating in the bloodstream is not available to the cells. It is closely bound to a copyright molecule called sex hormone--binding globulin, which we abbreviate as SHBG.
The biologically available part of overall testosterone is known as free testosterone, and it is readily available to the cells. Though it's just a small fraction of the 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.
Endocrine Society recommendations summarizedThis professional organization recommends testosterone therapy for men who have Therapy is not recommended for men who have
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Do time of day, diet, or other factors influence testosterone levels?
For many years, the recommendation was to receive a testosterone value early in the morning since levels start to drop after 10 or 11 a.m.. But the data behind this recommendation were attracted to healthy young men. Two recent studies demonstrated little change in blood glucose levels in men 40 and mature within the course of the day. One reported no change in average testosterone until after 2 p.m. Between 2 and 6 p.m., it went down by 13 percent, a small sum, and probably insufficient to affect identification. Most guidelines still say it is important to perform the evaluation in the morning, however for men 40 and over, 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 dietary supplements. By way of instance, it seems that individuals who have a diet low in protein have lower testosterone levels than men who consume more protein. But diet has not been studied thoroughly enough to make any recommendations that are clear.
Within the following article, testosterone-replacement treatment refers to the treatment of hypogonadism with adrenal gland -- testosterone that is manufactured outside the body. Depending upon the formula, treatment can lead to skin irritation, breast tenderness and enlargement, sleep apnea, acne, reduced sperm count, increased red blood cell count, and additional side effects.
Preliminary research has proven that clomiphene citrate (Clomid), a drug generally prescribed to stimulate ovulation in women struggling with infertility, may foster the production of natural testosterone, also termed endogenous testosterone, in men. Within four to six months, all the men had increased levels of testosteronenone reported any side effects throughout the year they were followed.
Since clomiphene citrate is not approved by the FDA for use in males, little information exists about the long-term ramifications of taking it (including the probability of developing prostate cancer) or whether it's more effective at boosting testosterone compared to exogenous formulations. But unlike adrenal gland, clomiphene citrate preserves -- and possibly enriches -- sperm production. That makes medication such as clomiphene citrate one of only a few choices for men with low testosterone that want to father children.
What kinds of testosterone-replacement treatment are available? *
The earliest form is an injection, which we use since it's cheap and because we faithfully get fantastic testosterone levels in nearly everybody. The disadvantage is that a person needs to come in every couple of weeks to get a shot. A roller-coaster effect may also occur as blood glucose levels peak and then return to research. [See"Exogenous vs. endogenous testosterone," above.]
Topical treatments help preserve a more uniform level of blood glucose. The first form of topical therapy has been a patch, but it has a very large rate of skin irritation. In one study, as many as 40 percent of men who used the patch developed a reddish area on their skin. That restricts its use.
The most widely used testosterone preparation from the United States -- and the one I begin almost everyone off with -- is a topical gel. The gel comes in miniature tubes or within a special dispenser, and you rub it on your shoulders or upper arms once a day. Based on my experience, it has a tendency to be absorbed to great levels in about 80% to 85 percent of guys, but that leaves a significant number who don't absorb sufficient for it to have a favorable impact. [For specifics on several different formulations, see table below.]
Are there any downsides to using gels? How long does it require them to work?
Men who start using the implants need to come back in to have their own testosterone levels measured again to make certain they are absorbing the right amount. Our goal is 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 although symptoms may not change for a month or two.