A Harvard expert shares his thoughts on testosterone-replacement therapy
An interview with Abraham Morgentaler, M.D.
It could be said that testosterone is the thing that makes guys, men. It gives them their characteristic deep voices, large muscles, and body and facial hair, differentiating them from women. It stimulates the growth of the genitals , plays a role in sperm production, fuels libido, and leads to regular erections. Additionally, it fosters the production of red blood cells, boosts mood, and assists cognition.
Over time, the testicular"machinery" which produces testosterone gradually becomes less powerful, and testosterone levels begin 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 libido and sense of energy, erectile dysfunction, diminished energy, reduced muscle mass and bone density, and nausea. Taken together, these signs and symptoms are often called hypogonadism ("hypo" significance low functioning and"gonadism" speaking to the testicles). Yet it is an underdiagnosed issue, with just about 5% of these 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 problems. He has developed specific experience in treating low testosterone levels. In this interview, Dr. Morgentaler shares his perspectives on current controversies, the treatment strategies he utilizes his own patients, and he thinks experts should reconsider the possible connection between testosterone-replacement therapy and prostate cancer.
Symptoms and diagnosisWhat symptoms and signs of low testosterone prompt the typical man 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 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, like more difficulty achieving an orgasm, less-intense climaxes, a much smaller amount of fluid out of ejaculation, and a feeling of numbness in the penis when they see or experience something which 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 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 are treated for benign prostatic hyperplasia, or BPH?
Not precisely. There are a number of drugs that may reduce libido, such as the BPH drugs finasteride (Proscar) and dutasteride (Avodart). Those drugs can also reduce the quantity of the ejaculatory fluid, no question. However a reduction in orgasm intensity usually does not go together 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 do you decide if or not a person is a candidate for testosterone-replacement treatment?
There are 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 these two approaches is far from ideal. Generally men with the lowest testosterone have the most symptoms and men with highest testosterone have 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 amounts, The Endocrine Society* believes low testosterone for a entire testosterone level of less than 300 ng/dl, and I believe that is a reasonable guide. However, no one really agrees on a few. 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 isn't quite as apparent.
| *Notice: The Endocrine Society recommends clinical practice guidelines with recommendations for who should and should not Look At This receive testosterone treatment. For my site a complete copy of these instructions, log on to www.endo-society.org. Is total testosterone the right thing to be measuring? Or if we are measuring something different? This is just another area of confusion and good debate, but I don't think it's as confusing as it appears to be 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 the testosterone that's circulating in the blood isn't readily available to the cells. It's tightly bound to a carrier molecule called sex hormone--binding globulin, which we abbreviate as SHBG. The available part of overall testosterone is known as free testosterone, and it is readily available to the cells. Though it's just a little fraction of the overall, the free testosterone level is a fairly good indicator of low testosterone. It's not perfect, but the significance is greater compared to total testosterone.
Do time of day, diet, or other elements influence testosterone levels? For many years, the recommendation was to get a testosterone value early in the morning since levels start 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 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 modest sum, and probably not enough to affect diagnosis. Most guidelines nevertheless say it is important to do the evaluation in the morning, however for men 40 and above, it likely doesn't matter much, provided that they get their blood drawn before 6 or 5 p.m. There are some rather 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 researched thoroughly enough to create any recommendations that are clear.
What kinds of testosterone-replacement therapy are available? * The earliest form is the injection, which we still use because it is cheap and because we reliably become fantastic testosterone levels in nearly everybody. The drawback is that a person needs to come in every few weeks to find a shot. A roller-coaster effect may also occur as blood testosterone levels peak and return to research. Topical treatments help maintain a more uniform level of blood glucose. The first kind of topical treatment was a patch, but it has a quite high rate of skin irritation. In one study, as many as 40 percent of people that used the patch developed a reddish area on their skin. That limits its use. The most commonly used testosterone preparation from the United States -- and also the one I begin almost everyone off -- is a topical gel. There are just two brands: AndroGel and Testim. The gel comes from miniature 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 consumed to great degrees in about 80% to 85 percent of guys, but leaves a substantial number who do not consume sufficient for this to have a favorable impact. [For details on several different formulations, see table ] Are there any drawbacks to using gels? How long does it take for them to work? Men who start using the gels have to come back in to have their testosterone levels measured again to make sure they're absorbing the right amount. Our target is that the mid to upper assortment of normal, which generally means approximately 500 to 600 ng/dl. The concentration of testosterone in blood actually goes up quite quickly, within a few doses. I normally measure it after 2 weeks, even although symptoms may not alter for a month or two. |