A Harvard expert shares his thoughts on testosterone-replacement therapy
A meeting with Abraham Morgentaler, M.D.
It could be said that testosterone is what makes men, guys. It gives them their characteristic deep voices, big muscles, and body and facial hair, differentiating them from women. It stimulates the growth of the genitals at puberty, plays a role in sperm production, fuels libido, and contributes to normal erections. It also fosters the production of red blood cells, boosts mood, and assists cognition.
As time passes, the "machinery" which produces testosterone slowly becomes less powerful, and testosterone levels begin to drop, by approximately 1 percent per year, starting in the 40s. As guys get in their 50s, 60s, and beyond, they might begin to have symptoms and signs of low testosterone like reduced libido and sense of energy, erectile dysfunction, diminished energy, decreased 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" referring to the testicles). Yet it is 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 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 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 he believes specialists should rethink the possible link 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 tend to observe men because they have sexual complaints. The main hallmark of reduced testosterone is low sexual desire or libido, but another may be erectile dysfunction, and any man who complains of erectile dysfunction must get his testosterone level checked. Men may experience different symptoms, such as more difficulty achieving an orgasm, less-intense climaxes, a lesser quantity of fluid from ejaculation, and a sense of numbness in the manhood when they see or experience something that would usually be arousing.
The more of the symptoms there are, the more likely it is that a man has low testosterone. Many physicians often dismiss these"soft symptoms" as a normal part of aging, however, they are often treatable and reversible by decreasing testosterone levels.
Aren't those the very same symptoms that men have when they're treated for benign prostatic hyperplasia, or BPH?
Not precisely. There are a number of medications that may reduce libido, such as the BPH drugs finasteride (Proscar) and dutasteride (Avodart). Those drugs may also decrease the amount 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 usually go together with it either, though surely if somebody has less sex drive or less attention, it's more of a struggle to get a fantastic erection.
How do you decide whether or not a person is a candidate for testosterone-replacement treatment?
There are two ways we determine whether somebody has reduced testosterone. One is a blood test and the other is by characteristic signs and symptoms, and the correlation between those two approaches is far from ideal. Generally guys with the lowest testosterone have the most symptoms and men with maximum testosterone have the least. But there are a number of men who have low levels of testosterone in their blood and have no signs.
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 think that's a sensible guide. But no one quite agrees on a few. It's not like diabetes, in which if your fasting glucose is above a certain level, they will say,"Okay, you've got it." With testosterone, that break point is not quite as apparent.
| *Notice: The Endocrine Society publishes clinical practice guidelines with recommendations for who should and should not receive testosterone treatment. For see hereclick to read more a complete copy of these instructions, log you could try here on to www.endo-society.org. |
Is complete testosterone the ideal thing to be measuring? Or if we are measuring something different?
Well, this is another area of confusion and good discussion, but I don't think it's as confusing as it is apparently in the literature. When most doctors learned about testosterone in medical school, they heard about overall testosterone, or all of the testosterone in the body. But about half of their testosterone that is circulating in the bloodstream is not readily available to cells.
The available part of total testosterone is known as free testosterone, and it is readily available to cells. Though it's just a small fraction of this overall, the free testosterone level is a fairly good indicator of low testosterone. It's not perfect, but the correlation is greater compared to testosterone.
Endocrine Society recommendations outlinedThis professional organization urges testosterone therapy for men who have both Therapy Isn't Suggested for men who've
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Do time of day, diet, or other factors affect testosterone levels?
For years, the recommendation has been to get a testosterone value early in the morning because levels start to drop after 10 or 11 a.m.. But the data behind that recommendation were drawn from healthy young men. Two recent studies showed little change in blood testosterone levels in men 40 and older over the course of the day. One reported no change in average testosterone until after 2 Between 2 and 6 p.m., it went down by 13%, a modest amount, and probably not enough to influence 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, provided that they obtain their blood drawn before 6 or 5 p.m.
There are some very interesting findings about diet. For example, it seems that those that have a diet low in protein have lower testosterone levels than males who consume more protein. But diet hasn't been studied thoroughly enough to create any recommendations that are clear.
Exogenous vs. endogenous testosteroneWithin the following article, testosterone-replacement therapy refers to the treatment of hypogonadism with exogenous testosterone -- testosterone that is produced outside the body. Based on the formulation, treatment can cause skin irritation, breast tenderness and enlargement, sleep apnea, acne, decreased sperm count, increased red blood cell count, along with additional side effects. Preliminary research has shown that clomiphene citrate (Clomid), a drug generally prescribed to stimulate ovulation in women struggling with infertility, can foster the creation of natural testosterone, also termed endogenous testosterone, in men. Within four to six months, all of the guys had increased levels of testosterone; none reported some side effects throughout the entire year they were followed. Because clomiphene citrate isn't approved by the FDA for use in men, little information exists regarding 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 adrenal gland, clomiphene citrate preserves -- and potentially enhances -- sperm production. This makes medication like clomiphene citrate one of just a few choices for men with low testosterone that want to father children. |
What kinds of testosterone-replacement therapy 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 drawback is that a man should come in every few weeks to find a shot. A roller-coaster effect can also happen as blood testosterone levels peak and return to research.
Topical treatments help maintain a more uniform amount of blood testosterone. The first kind 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 in their skin. That limits its usage.
The most commonly used testosterone preparation from the United States -- and the one I begin almost everyone off with -- is a topical gel. There are just two brands: AndroGel and Testim. According to my experience, it tends to be consumed to good degrees in about 80% to 85 percent of men, but leaves a significant number who don't consume enough for it to have a favorable effect. [For details 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 return in to have their testosterone levels measured again to be certain they're absorbing the proper quantity. Our target is the mid to upper assortment of normal, which usually means approximately 500 to 600 ng/dl. The concentration of testosterone in blood really goes up quite quickly, within several doses. I usually measure it after two weeks, even although symptoms may not change for a month or two.