A Harvard Specialist shares his thoughts on testosterone-replacement Treatment
It might be said that testosterone is what makes guys, guys. It gives them their characteristic deep voices, large muscles, and facial and body hair, differentiating them from girls. It stimulates the growth of the genitals at puberty, plays a role in sperm production, fuels libido, and leads to regular erections. It also fosters the creation of red blood cells, boosts mood, and aids cognition.
Over time, the "machinery" which produces testosterone gradually becomes less powerful, and testosterone levels start to fall, by approximately 1% a year, starting in the 40s. As men get in their 50s, 60s, and beyond, they might start to have symptoms and signs of low testosterone like lower libido and sense of vitality, erectile dysfunction, diminished energy, decreased muscle mass and bone density, and anemia. Taken together, these symptoms and signs are often called hypogonadism ("hypo" meaning low working and"gonadism" referring to the testicles). Researchers estimate that the illness affects anywhere from two to six million men in the United States. Yet it is an underdiagnosed issue, with only about 5 percent of those affected undergoing therapy.
But little consensus exists on 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 reproductive and sexual difficulties. He's developed particular experience in treating low testosterone levels. In this interview, Dr. Morgentaler shares his views on current controversies, the treatment plans he utilizes his own patients, and he thinks specialists should rethink the possible connection between testosterone-replacement treatment and prostate cancer.
Symptoms like this and find more information diagnosisWhat signs and symptoms of low testosterone prompt that the average man to find a doctor?
As a urologist, I have a tendency to observe men since 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 guy 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 quantity of fluid from ejaculation, and a sense 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 tend to discount those"soft symptoms" as a normal part of aging, but they're often treatable and reversible by normalizing testosterone levels.
Aren't those the very same symptoms that guys have when they're treated for benign prostatic hyperplasia, or BPH?
Not exactly. There are a number of medications which may lessen sex drive, including the BPH drugs finasteride (Proscar) and dutasteride (Avodart). Those drugs may also decrease the amount of the ejaculatory fluid, no question. However a decrease in orgasm intensity usually does not go along with therapy for BPH. Erectile dysfunction does not ordinarily go together with it , though certainly if a person 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 just two ways we determine whether someone has low testosterone. One is a blood test and the other is by characteristic symptoms and signs, and the correlation between these two approaches is far from ideal. Normally guys with the lowest testosterone have the most symptoms and guys with highest testosterone have the least. But there are some men who have low levels of testosterone in their blood and have no symptoms.
Looking purely 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, in which if your fasting sugar is over 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 should and should not receive testosterone treatment. |
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 discussion, but I don't think it's as confusing as it appears to be in the literature. When most doctors learned about testosterone in medical school, they heard about overall testosterone, or all of the testosterone in the human body. However, about half of their testosterone that's circulating in the blood isn't available to the cells. It's tightly bound to a carrier molecule known as sex hormone--binding globulin, which we abbreviate as SHBG.
The available portion of overall testosterone is known as free testosterone, and it's readily available to the cells. Though it's only a small fraction 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 testosterone.
Endocrine Society recommendations summarizedThis professional organization recommends testosterone therapy for men who have Therapy Isn't Suggested for men who have
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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 fall after 10 or even 11 a.m.. But the information behind that recommendation were drawn from healthy young men. Two recent studies demonstrated little change in blood testosterone levels in men 40 and mature within the course of the day. One reported no change in average testosterone till after 2 Between 6 and 2 p.m., it went down by 13%, a small sum, and probably not enough to affect diagnosis. Most guidelines still say it is important to do the evaluation in the morning, but for men 40 and over, 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 diet. By way of example, it seems that individuals that have a diet low in protein have lower testosterone levels than men who eat more protein. But diet hasn't been researched thoroughly enough to make any recommendations that are clear.
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 formula, therapy can lead to skin irritation, breast tenderness and enlargement, sleep apnea, acne, decreased sperm count, increased red blood cell count, and additional side effects.
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.
Since clomiphene citrate is not approved by the FDA for use in males, little information exists about the long-term effects of carrying it (such as the risk 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 possibly enriches -- sperm production. This makes drugs like clomiphene citrate one of just a few options for men with low testosterone that want to father children.
FormulationsWhat kinds of testosterone-replacement treatment can be found? *
The oldest form is an injection, which we still use because it is cheap and since we faithfully get fantastic testosterone levels in almost everybody. The disadvantage is that a man needs to come in every few weeks to find a shot. A roller-coaster effect may also happen as blood glucose levels peak and return to baseline.
Topical treatments help preserve a more uniform amount of blood glucose. The first kind of topical therapy was a patch, but it has a very high rate of skin irritation. In one study, as many as 40 percent of people that used the patch developed a reddish area in their skin. That restricts its usage.
The most commonly used testosterone preparation from the United States -- and also the one I begin almost everyone off -- is a topical gel. The gel comes from 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 tends to be consumed to great degrees in about 80% to 85 percent of guys, but leaves a significant number who do not consume enough for it to have a positive effect. [For specifics 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 return in to have their own testosterone levels measured again to be certain they are absorbing the proper amount. Our target is the mid to upper range of normal, which usually means approximately 500 to 600 ng/dl. The concentration of testosterone in blood actually goes up quite quickly, within several doses. I normally measure it after two weeks, although symptoms may not alter for a month or two.