A Harvard expert shares his Ideas on testosterone-replacement Treatment
It might be stated that testosterone is what makes men, guys. 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. It also boosts the production of red blood cells, boosts mood, and aids cognition.
As time passes, the "machinery" that makes testosterone slowly becomes less effective, and testosterone levels start to drop, by about 1% a year, beginning in the 40s. As guys get into their 50s, 60s, and beyond, they may begin to have signs and symptoms of low testosterone such as reduced sex drive and sense of energy, erectile dysfunction, decreased energy, reduced muscle mass and bone density, and nausea. Taken together, these signs and symptoms are often referred to as hypogonadism ("hypo" meaning low functioning and"gonadism" speaking to the testicles). Yet it's an underdiagnosed problem, with just about 5% of these affected receiving treatment.
Various studies have shown that testosterone-replacement therapy may provide a wide selection of benefits for men with hypogonadism, such as improved 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 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 ailments and male sexual and reproductive difficulties. He's developed particular experience in treating low testosterone levels. In this interview, Dr. Morgentaler shares his perspectives on current controversies, the treatment plans he uses with his patients, and he thinks specialists should rethink the possible connection between testosterone-replacement therapy and prostate cancer.
Symptoms and diagnosisWhat symptoms and signs of low testosterone prompt that the average person to see a doctor?
As a urologist, I have a tendency to see guys since they have sexual complaints. The primary hallmark of reduced testosterone is reduced sexual desire or libido, but another may be erectile dysfunction, and some other man who complains of erectile dysfunction must 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 manhood when they see or experience something which 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 tend to discount 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, such as the BPH drugs finasteride (Proscar) and dutasteride (Avodart). Those drugs can also reduce the quantity of the ejaculatory fluid, no wonder. However a decrease in orgasm intensity usually does not go along with treatment for BPH. Erectile dysfunction does not usually go together with it , though certainly if a person has less sex drive or less attention, it's more of a struggle to have a fantastic erection.
How do you determine whether or not a person is a candidate for testosterone-replacement treatment?
There are just 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 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 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 these details should and should not receive testosterone Source therapy. For a complete copy of these instructions, log on to www.endo-society.org. Is complete testosterone the ideal point to be measuring? Or if we are measuring something different? This is just another area of confusion and great debate, but I don't think it's as confusing as it appears to be from 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 their 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 total testosterone is called free testosterone, and it's readily available to cells. Though it's just a small fraction of the overall, the free testosterone level is a fairly good indicator of low testosterone. It's not ideal, but the significance is greater than with total testosterone.
Do time of day, diet, or other elements affect testosterone levels? For years, the recommendation has been to receive a testosterone value early in the morning since levels begin to drop 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 not enough to affect diagnosis. Most guidelines nevertheless say it's important to perform the test in the morning, however for men 40 and above, it probably doesn't matter much, provided that they get their blood drawn before 6 or 5 p.m. There are some rather interesting findings about diet. By way of example, it appears that those who have a diet low in protein have lower testosterone levels than males who consume more protein. But diet hasn't been researched thoroughly enough to make any clear recommendations. Within this guide, testosterone-replacement treatment refers to the treatment of hypogonadism with exogenous testosterone -- testosterone that's manufactured outside the body. Based on the formulation, therapy can cause 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 months, all of the guys had heightened levels of testosterone; none reported some side effects throughout the year they had been followed. Since clomiphene citrate is not approved by the FDA for use in males, little information exists regarding the long-term effects of carrying it (including the probability of developing prostate cancer) or whether it is more capable of boosting testosterone compared to exogenous formulations. But unlike exogenous testosterone, clomiphene citrate maintains -- and potentially enhances -- sperm production. That makes medication such as clomiphene citrate one of only a few choices for men with low testosterone who wish to father children. What kinds of testosterone-replacement treatment are available? * The oldest form is the injection, which we use since it is cheap and since we reliably get good testosterone levels in almost everybody. The drawback is that a person needs to come in every few weeks to get a shot. A roller-coaster effect can also occur as blood testosterone levels peak and then return to research. Topical treatments help preserve a more uniform amount of blood testosterone. The first form of topical therapy was 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 use. The most commonly used testosterone preparation in the United States -- and the one I start almost everyone off -- is a topical gel. There are two brands: AndroGel and Testim. Based on my experience, it tends to be absorbed to good levels in about 80% to 85% of men, but that leaves a substantial number who don't absorb enough for it to have a positive impact. [For details on several different formulations, see table ] Are there any downsides 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 own testosterone levels measured again to be certain they are absorbing the right amount. Our goal is the mid to upper range of normal, which usually means around 500 to 600 ng/dl. The concentration of testosterone in blood actually goes up quite quickly, within several doses. I normally measure it after 2 weeks, even though symptoms may not change for a month or two. |