A Harvard expert shares his thoughts on testosterone-replacement therapy
It might be said that testosterone is what makes men, men. It gives them their characteristic deep voices, large muscles, and facial and body hair, differentiating them from girls. It stimulates the development of the genitals , plays a role in sperm production, fuels libido, and contributes to normal erections. It also fosters the production of red blood cells, boosts mood, and aids cognition.
Over time, the testicular"machinery" that makes testosterone gradually becomes less powerful, and testosterone levels begin to drop, by approximately 1 percent per year, starting in the 40s. As guys get in their 50s, 60s, and beyond, they might start to have symptoms and signs of low testosterone like lower sex drive and sense of vitality, erectile dysfunction, decreased energy, reduced muscle mass and bone density, and anemia. Taken together, these symptoms and signs are often referred to as hypogonadism ("hypo" significance low working and"gonadism" speaking to the testicles). Yet it's an underdiagnosed problem, with only about 5% of these affected undergoing therapy.
But little consensus exists about what constitutes low testosterone, when testosterone supplementation makes sense, or what dangers patients face. 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 difficulties. He's developed specific experience in treating low testosterone levels. In this interview, Dr. Morgentaler shares his views on current controversies, the treatment plans he utilizes his patients, and why he thinks experts should reconsider the potential connection between testosterone-replacement treatment and prostate cancer.
Symptoms and diagnosisWhat signs and symptoms of low testosterone prompt the typical person to see a doctor?
As a urologist, I tend to observe men because they have sexual complaints. The main hallmark of reduced testosterone is low sexual desire or libido, but another may be erectile dysfunction, and some other man who complains of erectile dysfunction should possess his testosterone level checked. Men can experience other symptoms, like more trouble achieving an orgasm, less-intense orgasms, a lesser amount of fluid from ejaculation, and a sense 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, however, they are often treatable and reversible by decreasing testosterone levels.
Are not those the same symptoms that guys have when they're treated for benign prostatic hyperplasia, or BPH?
Not precisely. There are quite a few drugs which may reduce libido, including the BPH drugs finasteride (Proscar) and dutasteride (Avodart). Those drugs may also reduce the amount of the ejaculatory fluid, no question. However a decrease in orgasm intensity usually doesn't go along with therapy for BPH. Erectile dysfunction does not ordinarily go along with it , though surely if a person has less sex drive or less interest, it is more of a challenge to have a good erection.
How can you determine whether or not a man is a candidate for testosterone-replacement treatment?
There are two ways we determine whether somebody has reduced testosterone. One is a blood test and the other is by characteristic signs and symptoms, and the correlation between those two approaches is far from perfect. Normally men with the lowest testosterone have the most symptoms and guys with highest testosterone possess the least. However, there are some guys who have low levels of testosterone in their blood and have no signs.
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 believe that's a sensible guide. But no one quite agrees on a few. It is not like diabetes, where 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 who should click reference and visit homepage should not article source receive testosterone treatment. Is total testosterone the ideal point to be measuring? Or should we be measuring something different? This is another area of confusion and good discussion, but I don't think it's as confusing as it is apparently from the literature. When most doctors learned about testosterone in medical school, they learned about total testosterone, or all of the testosterone in the human body. But about half of the testosterone that's circulating in the blood isn't readily available to the cells. It's closely bound to a carrier molecule known as sex hormone--binding globulin, which we abbreviate as SHBG. The biologically available part of overall testosterone is known as free testosterone, and it is readily available to cells. Nearly every laboratory has a blood test to measure free testosterone. Though it's only a small fraction of the overall, the free testosterone level is a fairly good indicator of reduced testosterone. It is not ideal, but the correlation is greater than with total testosterone. This professional organization recommends testosterone therapy for men who have
Therapy is not recommended for men who've
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Do time of day, diet, or other factors affect testosterone levels?
For years, the recommendation was to receive a testosterone value early in the morning because levels start to fall after 10 or even 11 a.m.. But the information behind this recommendation were attracted to healthy young men. Two recent studies demonstrated little change in blood glucose levels in men 40 and mature over the course of the day. One reported no change in average testosterone until after 2 Between 6 and 2 p.m., it went down by 13 percent, a modest amount, and probably not enough to influence identification. Most guidelines nevertheless say it is important to perform the evaluation in the morning, but for men 40 and above, it probably does not matter much, provided that they obtain their blood drawn before 5 or 6 p.m.
There are some very interesting findings about dietary supplements. By way of instance, it appears 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 clear recommendations.
Exogenous vs. endogenous testosteroneIn this guide, testosterone-replacement treatment refers to the treatment of hypogonadism with exogenous testosterone -- testosterone that is produced outside the body. Based on the formulation, therapy can cause skin irritation, breast enlargement and tenderness, sleep apnea, acne, reduced sperm count, increased red blood cell count, along with other side effects. Preliminary research has proven that clomiphene citrate (Clomid), a drug generally prescribed to stimulate ovulation in women struggling with infertility, may foster the production of natural testosterone, also termed endogenous testosterone, in men. Within four to six weeks, all of the guys had heightened levels of testosterone; none reported some side effects during the entire year they had been followed. Because clomiphene citrate isn't approved by the FDA for use in men, little information exists regarding the long-term effects of carrying it (including the risk of developing prostate cancer) or if it is more capable of boosting testosterone than exogenous formulations. But unlike adrenal gland, clomiphene citrate preserves -- and potentially enhances -- sperm production. This makes drugs like clomiphene citrate one of just a few choices for men with low testosterone that want to father children. What kinds of testosterone-replacement therapy can be found? * The oldest form is the injection, which we still use since it's cheap and because we faithfully get fantastic testosterone levels in nearly everybody. The drawback is that a man should come in every few weeks to find a shot. A roller-coaster effect may also occur as blood glucose levels peak and then return to research. [See"Exogenous vs. endogenous testosterone," above.] Topical treatments help maintain a more uniform amount of blood testosterone. The first form of topical treatment was a patch, but it has a quite high rate of skin irritation. In one study, as many as 40 percent of men who used the patch developed a reddish area in their skin. That limits its usage. The most commonly used testosterone preparation in the United States -- and also the one I start almost everyone off -- is a topical gel. The gel comes in miniature tubes or within a special dispenser, and you rub it on your shoulders or upper arms once a day. Based on my experience, it has a tendency to be absorbed to great degrees in about 80% to 85% of men, but leaves a significant number who do not absorb enough for this to have a positive effect. [For details on several different formulations, see table below.] 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 own testosterone levels measured again to make certain they are absorbing the proper amount. Our target is that the mid to upper assortment of normal, which usually means around 500 to 600 ng/dl. The concentration of testosterone in blood actually goes up quite fast, in just a few doses. I usually measure it after 2 weeks, even although symptoms may not change for a month or two. |