A Harvard expert shares his thoughts on testosterone-replacement therapy
It could be stated that testosterone is the thing that makes men, men. It gives them their characteristic deep voices, big muscles, and body and facial hair, distinguishing them from women. It stimulates the development of the genitals , 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 aids cognition.
As time passes, the testicular"machinery" that produces testosterone gradually becomes less effective, and testosterone levels begin to fall, by about 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 lower sex drive and sense of energy, erectile dysfunction, diminished energy, reduced muscle mass and bone density, and anemia. Taken together, these symptoms and signs are often called hypogonadism ("hypo" significance low working and"gonadism" referring to the testicles). Yet it is an underdiagnosed issue, with only about 5 percent of those affected undergoing therapy.
Various studies have shown that testosterone-replacement therapy can offer a vast range of advantages for men with hypogonadism, including enhanced libido, mood, cognition, muscle mass, bone density, and red blood cell production. 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 diseases and male sexual and reproductive problems. He has developed specific expertise in treating lower testosterone levels. In this interview, Dr. Morgentaler shares his views on current controversies, the treatment strategies he utilizes his own patients, and he thinks experts should reconsider the potential connection between testosterone-replacement therapy and prostate cancer.
Symptoms and diagnosisWhat symptoms and signs of low testosterone prompt the typical man to find a physician?
As a urologist, I tend to observe men because 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 should possess his testosterone level checked. Men may experience other symptoms, like more difficulty achieving an orgasm, less-intense orgasms, 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, but they are often treatable and reversible by decreasing testosterone levels.
Are not those the same symptoms that men have when they are treated for benign prostatic hyperplasia, or BPH?
Not precisely. There are a number of drugs which may reduce libido, including the BPH medication finasteride (Proscar) and dutasteride (Avodart). Those drugs may also reduce the amount of the ejaculatory fluid, no question. However a decrease in orgasm intensity normally does not go along with treatment 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 challenge to get a good erection.
How do you decide if or not a person is a candidate for testosterone-replacement therapy?
There are two ways that 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 perfect. Generally men with the lowest testosterone have the most symptoms and men with highest testosterone have the least. But there are a number of guys who have reduced levels of testosterone in their blood and have no signs.
Looking at the biochemical numbers, The Endocrine Society* considers low testosterone to be a total testosterone level of less than 300 ng/dl, and I think that's a reasonable guide. But no one quite agrees on a number. It's not like diabetes, where if your fasting glucose is above a certain level, they'll say,"Okay, you've got it." With testosterone, that break point is not quite as apparent.
| *Notice: The Endocrine Society recommends clinical practice guidelines with recommendations for who should and should not receive testosterone treatment. For a view itvisit this site complete copy of these instructions, log on to www.endo-society.org. Is total testosterone the right thing to be measuring? Or should we be 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 physicians learned about testosterone in medical school, they heard about overall testosterone, or all the testosterone in the body. But about half of the testosterone that is circulating in the blood isn't available to the cells. It's closely bound to a carrier molecule known as sex hormone--binding globulin, which we abbreviate as SHBG. The available portion of overall testosterone is called free testosterone, and it is readily available to cells. Though it's only a small portion of this overall, the free testosterone level is a pretty good indicator of low testosterone. It is not ideal, but the correlation is greater than with total testosterone.
Do time daily, diet, or other elements affect testosterone levels? For many years, the recommendation has been to get a testosterone value early in the morning since levels start to fall after 10 or even 11 a.m.. But the data behind this recommendation were drawn from healthy young men. Two recent studies demonstrated 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 6 and 2 p.m., it went down by 13%, a small amount, and probably insufficient to influence diagnosis. Most guidelines nevertheless say it's important to perform the test in the morning, however for men 40 and above, it probably does not 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. 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 studied thoroughly enough to make any recommendations that are clear. Within this guide, testosterone-replacement therapy refers to the treatment of hypogonadism with adrenal gland -- testosterone that is manufactured outside the body. Based on the formula, treatment can lead to skin irritation, breast tenderness and enlargement, sleep apnea, acne, reduced sperm count, increased red blood cell count, and additional side effects. In a recent prospective study, 36 hypogonadal men took a daily dose of clomiphene citrate for three or more months. Within four to six weeks, each one the guys had heightened levels of testosterone; none reported some side effects during the year they had been followed. Because clomiphene citrate is not accepted by the FDA for use in males, little information exists about the long-term effects of carrying it (including the risk of developing prostate cancer) or if it's more effective at boosting testosterone than exogenous formulas. But unlike adrenal gland, clomiphene citrate preserves -- and potentially enriches -- sperm production. That makes drugs such as clomiphene citrate one of just a few options for men with low testosterone who want to father children. What kinds of testosterone-replacement treatment are available? * The oldest form is the injection, which we use because it is cheap and because we reliably get fantastic testosterone levels in almost everybody. The disadvantage is that a man needs to come in every couple of weeks to find a shot. A roller-coaster effect can also occur as blood testosterone levels peak and then return to research. Topical treatments help maintain 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 one study, as many as 40% of men who used the patch developed a red area on their skin. That restricts its usage. The most widely used testosterone preparation from the United States -- and the one I start almost everyone off with -- is a topical gel. The gel comes in tiny tubes or within 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 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 various formulations, see table below.] 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 certain they are absorbing the proper quantity. Our goal is the mid to upper assortment of normal, which generally means around 500 to 600 ng/dl. The concentration of testosterone in the blood really goes up quite quickly, within a few doses. I usually measure it after two weeks, even although symptoms may not alter for a month or two. |