A Harvard Specialist shares his Ideas on testosterone-replacement therapy
An interview with Abraham Morgentaler, M.D.
It might be said that testosterone is the thing that makes men, guys. It gives them their characteristic deep voices, big muscles, and body and facial 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 normal erections. Additionally, it boosts the production of red blood cells, boosts mood, and assists cognition.
Over time, the "machinery" that produces testosterone gradually becomes less effective, and testosterone levels begin to fall, by approximately 1 percent a year, starting in the 40s. As men get into their 50s, 60s, and beyond, they might start to have symptoms and signs of low testosterone such as reduced sex drive and sense of vitality, erectile dysfunction, diminished energy, reduced muscle mass and bone density, and anemia. Taken together, these symptoms and signs are often called hypogonadism ("hypo" meaning low working and"gonadism" speaking to the testicles). Researchers estimate that the condition affects anywhere from two to six million men in the USA. Yet it's an underdiagnosed problem, with just about 5 percent of those 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 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 reproductive and sexual problems. He has developed particular expertise in treating lower testosterone levels. In this interview, Dr. Morgentaler shares his perspectives on current controversies, the treatment plans he uses with his own patients, and why he thinks specialists should rethink the possible link between testosterone-replacement therapy and prostate cancer.
Symptoms and diagnosisWhat symptoms and signs of low testosterone prompt that the typical man to see a doctor?
As a urologist, I tend to observe guys since they have sexual complaints. The main hallmark of low testosterone is low sexual desire or libido, but another can be erectile dysfunction, and any guy who complains of erectile dysfunction must possess his testosterone level checked. Men can experience other symptoms, such as more difficulty achieving an orgasm, less-intense orgasms, a lesser quantity of fluid out of ejaculation, and a feeling of numbness in the manhood when they see or experience something which would usually be arousing.
The more of the symptoms there are, the more likely it is that a man has low testosterone. Many physicians tend to dismiss these"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 guys have when they are treated for benign prostatic hyperplasia, or BPH?
Not precisely. There are quite a few medications which may reduce libido, such as the BPH drugs finasteride (Proscar) and dutasteride (Avodart). Those drugs can also decrease the quantity of the ejaculatory fluid, no wonder. However a reduction in orgasm intensity usually does not 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 struggle to get a good erection.
How do you decide if or not a man is a candidate for testosterone-replacement therapy?
There are just two ways we determine whether somebody has reduced testosterone. One is a blood test and the other one is by characteristic symptoms and signs, and the correlation between those two methods is far from ideal. Normally men with the lowest testosterone have the most symptoms and men with maximum testosterone possess the least. But 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 for a total testosterone level of less than 300 ng/dl, and I think that is a sensible guide. But no one quite 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 is not quite as clear.
| *Notice: The Endocrine Society publishes clinical practice guidelines with recommendations for find out here who should and shouldn't receive testosterone treatment. For a complete copy of the instructions, log on to www.endo-society.org. Is complete testosterone the ideal thing to be measuring? Or if we are measuring something else? This is just another area of confusion and great 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 overall testosterone, or all the testosterone in the human body. However, about half of the testosterone that is circulating in the bloodstream isn't available to cells. It's closely bound to a carrier molecule known as sex hormone--binding globulin, which we abbreviate as SHBG. The biologically available portion of total testosterone is known as free testosterone, and it's readily available to cells. 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.
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.. However, the information behind that recommendation were attracted to healthy young men. Two recent studies showed little change in blood testosterone levels in men 40 and older within the course of the day. One reported no change in typical testosterone till after 2 p.m. Between 2 and 6 p.m., it went down by 13 percent, a small amount, and probably insufficient to affect diagnosis. Most guidelines still say it is important to perform the test in the morning, but for men 40 and over, it probably doesn't matter much, provided that they obtain their blood drawn before 5 or 6 p.m. There are a number of rather interesting findings about diet. 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 make any recommendations that are clear. In the following guide, testosterone-replacement treatment refers to the treatment of hypogonadism with adrenal gland -- testosterone that is manufactured outside the body. Depending on the formula, therapy can lead to skin irritation, breast enlargement and tenderness, sleep apnea, acne, reduced sperm count, increased red blood cell count, along with additional side effects. At a recent prospective study, 36 hypogonadal men took a daily dose of clomiphene citrate for three or more months. Within four to six months, all of the men had heightened levels of testosterone; none 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 regarding the long-term effects of taking it (including the risk of developing prostate cancer) or whether it is more effective at boosting testosterone than exogenous formulations. But unlike adrenal gland, clomiphene citrate maintains -- and potentially enriches -- sperm production. This makes medication like clomiphene citrate one of only a few choices for men with low testosterone who wish to father children. |
What kinds of testosterone-replacement treatment can be found? *
The earliest form is an injection, which we still use because it's cheap and since we faithfully become good testosterone levels in nearly everybody. The disadvantage is that a person should come in every couple of weeks to find a shot. A roller-coaster effect may also occur as blood testosterone levels peak and then return to research.
Topical treatments help maintain a more uniform level of blood glucose. The first kind of topical therapy was a patch, but it has a very large rate of skin irritation. In 1 study, as many as 40% of men who used the patch developed a reddish area in their skin. That limits its use.
The most widely used testosterone preparation from the United States -- and the one I begin almost everyone off -- is a topical gel. There are two brands: AndroGel and Testim. Based on my experience, it has a tendency to be consumed to good levels in about 80% to 85 percent of men, but that leaves a significant number who don't absorb sufficient for it to have a positive impact. [For specifics on various formulations, see table ]
Are there any drawbacks to using dyes? How long does it take for them to get the job done?
Men who start using the gels have to return in to have their testosterone levels measured again to be sure they're absorbing the proper amount. 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, in just several doses. I usually measure it after 2 weeks, although symptoms may not change for a month or two.