A Harvard Specialist shares his thoughts on testosterone-replacement Treatment
It could be stated that testosterone is what makes guys, guys. It gives them their characteristic deep voices, large muscles, and body and facial hair, distinguishing them from girls. It stimulates the growth of the genitals , plays a role in sperm production, fuels libido, and contributes to regular erections. It also boosts the creation of red blood cells, boosts mood, and aids cognition.
As time passes, the testicular"machinery" that produces testosterone gradually becomes less powerful, and testosterone levels begin to fall, by approximately 1 percent a year, starting in the 40s. As guys get into their 50s, 60s, and beyond, they might begin to have signs and symptoms of low testosterone like reduced sex drive and sense of energy, erectile dysfunction, decreased energy, reduced muscle mass and bone density, and nausea. Taken together, these symptoms and signs are often called hypogonadism ("hypo" significance low working and"gonadism" referring to the testicles). Yet it's an underdiagnosed problem, with only about 5 percent of these affected receiving treatment.
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 ailments and male reproductive and sexual difficulties. He has developed particular experience in treating lower testosterone levels. In this interview, Dr. Morgentaler shares his perspectives on current controversies, the treatment strategies he uses with his own patients, and why he believes specialists should rethink the potential link between testosterone-replacement therapy and prostate cancer.
Symptoms and diagnosisWhat signs and symptoms 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 low sexual desire or libido, but another may be erectile dysfunction, and some other guy who complains of erectile dysfunction must possess his testosterone level checked. Men can experience different symptoms, like more trouble achieving an orgasm, less-intense climaxes, a smaller amount of fluid from ejaculation, and a feeling of numbness in the penis when they see or experience something that would normally be arousing.
The more of these symptoms there are, the more likely it is that a man has low testosterone. Many physicians often discount those"soft symptoms" as a normal part of aging, however, they're often treatable and reversible by decreasing 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 medication finasteride (Proscar) and dutasteride (Avodart). Those drugs may also decrease the amount of the ejaculatory fluid, no question. But a reduction in orgasm intensity usually does not go together with therapy for BPH. Erectile dysfunction does not ordinarily go together with it , though certainly if somebody has less sex drive or less interest, it's more of a struggle to have a fantastic erection.
How can you determine whether a person is a candidate for testosterone-replacement treatment?
There are just two ways we determine whether someone has reduced testosterone. One is a blood test and the other 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 highest testosterone have the least. However, there are a number of men who have low levels of testosterone in their blood and have no symptoms.
Looking at the biochemical numbers, 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 really agrees on a few. It's similar to 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 clear.
| *Notice: The Endocrine Society publishes clinical practice guidelines with recommendations for who should and shouldn't view receive testosterone treatment. For a complete copy of the guidelines, log on to www.endo-society.org. Is total testosterone the ideal thing to be measuring? Or should we be measuring something different? Well, this is another area of confusion and good debate, but I do not think it's as confusing as it appears to be from the literature. When most doctors learned about testosterone in medical school, they heard about overall testosterone, or all the testosterone in the body. However, about half of their testosterone that's circulating in the blood is not readily available to the cells. It is closely bound to a carrier molecule called sex hormone--binding globulin, which we abbreviate as SHBG. The 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 low testosterone. It's not ideal, but the correlation is greater compared to total testosterone.
Do time daily, diet, or other factors affect testosterone levels? For many years, the recommendation has been 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 mature over the course of this day. One reported no change in typical testosterone until after 2 p.m. Between 6 and 2 p.m., it went down by 13 percent, a modest 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 likely doesn't matter much, as long as they obtain their blood drawn before 6 or 5 p.m. There are some very interesting findings about dietary supplements. By way of example, it appears that individuals 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.
What kinds of testosterone-replacement treatment can be found? * The earliest form is the injection, which we use because it's cheap and since we faithfully become fantastic testosterone levels in almost everybody. The drawback is that a man needs to come in every few weeks to get a shot. A roller-coaster effect can also occur as blood testosterone levels peak and return to baseline. [See"Exogenous vs. endogenous testosterone," above.] Topical therapies help maintain a more uniform level of blood glucose. The first kind of topical treatment has been a patch, but it has a very high rate of skin irritation. In one study, as many as 40% of men who used the patch developed a reddish area in their skin. That restricts its usage. The most widely used testosterone preparation from the United States -- and the one I start almost everyone off -- is a topical gel. The gel comes in miniature tubes or in a unique dispenser, and you rub it on your shoulders or upper arms once a day. According to my experience, it has a tendency to be consumed to good levels in about 80% to 85% of guys, but leaves a substantial number who don't consume sufficient for it to have a positive impact. [For details on several different formulations, see table below.] Are there any drawbacks to using gels? How long does it take for them to work? Men who begin using the implants need to come back in to have their testosterone levels measured again to be certain they are absorbing the right amount. Our goal is that the mid to upper range of normal, which generally means approximately 500 to 600 ng/dl. The concentration of testosterone in the blood actually goes up quite fast, in just a few doses. I normally measure it after two weeks, although symptoms may not change for a month or two. |