A Harvard Specialist shares his thoughts 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, large muscles, and body and facial hair, distinguishing 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. Additionally, it fosters the creation of red blood cells, boosts mood, and aids cognition.
Over time, the testicular"machinery" which produces testosterone gradually becomes less powerful, and testosterone levels start to drop, by approximately 1% per year, beginning in the 40s. As men get in their 50s, 60s, and beyond, they might begin to have symptoms and signs of low testosterone such as reduced libido and sense of vitality, erectile dysfunction, decreased energy, reduced muscle mass and bone density, and anemia. Taken together, these signs and symptoms are often referred to as hypogonadism ("hypo" significance low working and"gonadism" referring 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 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 difficulties. He's developed specific expertise in treating lower testosterone levels. In this interview, Dr. Morgentaler shares his views on current controversies, the treatment plans he uses with his own patients, and why he thinks experts should reconsider the potential link between testosterone-replacement therapy and prostate cancer.
Symptoms and diagnosisWhat symptoms and signs of low testosterone prompt that the typical person to find a physician?
As a urologist, I have a tendency to see men because they have sexual complaints. The primary 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 can experience different symptoms, like more trouble achieving an orgasm, less-intense orgasms, a smaller quantity of fluid from ejaculation, and a feeling of numbness in the manhood when they see or experience something that would normally be arousing.
The more of the symptoms you will find, the more likely it is that a man has low testosterone. Many physicians often dismiss those"soft symptoms" as a normal part of aging, however, they're often treatable and reversible by normalizing testosterone levels.
Are not those the very same symptoms that men have when they're treated for benign prostatic hyperplasia, or BPH?
Not precisely. There are quite a few drugs which may reduce libido, such as the BPH medication finasteride (Proscar) and dutasteride (Avodart). Those drugs may also decrease the quantity of the ejaculatory fluid, no question. But a reduction in orgasm intensity normally does not go along with treatment for BPH. Erectile dysfunction does not usually go along with it , though certainly if a person has less sex drive or less attention, it is more of a challenge to have a fantastic erection.
How do you determine if or not a person 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 ideal. Normally men with the lowest testosterone have the most symptoms and men with maximum testosterone have the least. However, there are a number of guys who have low levels of testosterone in their blood and have no symptoms.
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 is a reasonable guide. But no one quite agrees on a number. It's similar to diabetes, where 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.
*Notice: The Endocrine Society publishes clinical practice guidelines with recommendations for who should and should important link not receive testosterone treatment. her response Is complete testosterone the right point to be measuring? Or should we be measuring something different? This is another area of confusion and great discussion, but I do not 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 the testosterone in the body. But about half of their testosterone that's circulating in the blood isn't available to cells. It is 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 called free testosterone, and it's readily available to cells. Even though it's just a small fraction of the overall, the free testosterone level is a fairly good indicator of reduced testosterone. It is not perfect, but the correlation is greater compared to testosterone.
Do time of day, diet, or other factors affect testosterone levels? For years, the recommendation has been to receive 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 attracted to 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 typical testosterone till after 2 p.m. Between 2 and 6 p.m., it went down by 13 percent, a small amount, and probably not enough to influence diagnosis. Most guidelines still say it is important to perform the evaluation in the morning, however for men 40 and over, it likely doesn't matter much, as long as they obtain their blood drawn before 5 or 6 p.m. There are a number of very 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 create any clear recommendations.
What forms of testosterone-replacement treatment are available? * The earliest form is the injection, which we still use because it's cheap and since we reliably become good testosterone levels in nearly everybody. The disadvantage is that a person should come in every couple of 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 level of blood testosterone. The first form of topical therapy has been a patch, but it has a quite large rate of skin irritation. In 1 study, as many as 40% of men who used the patch developed a red area on their skin. That limits its usage. The most widely 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. According to my experience, it has a tendency to be consumed to great degrees in about 80% to 85 percent of guys, but leaves a significant number who do not consume sufficient for this to have a favorable impact. [For details on several different formulations, see table ] Are there any downsides to using dyes? How much time does it require them to get the job done? Men who begin using the implants need to return in to have their own testosterone levels measured again to be certain they are absorbing the proper quantity. Our goal 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 usually measure it after two weeks, though symptoms may not change for a month or two. |