A Harvard Specialist shares his Ideas on testosterone-replacement therapy
It might be stated that testosterone is what makes men, men. It gives them their characteristic deep voices, big muscles, and body and facial hair, distinguishing them from women. It stimulates the growth of the genitals at puberty, plays a role in sperm production, fuels libido, and contributes to normal erections. Additionally, it boosts the creation of red blood cells, boosts mood, and assists cognition.
As time passes, the "machinery" which produces testosterone slowly becomes less powerful, and testosterone levels start to fall, by about 1% a year, beginning in the 40s. As men get into their 50s, 60s, and beyond, they may start to have symptoms and signs of low testosterone like lower libido and sense of energy, erectile dysfunction, diminished energy, reduced muscle mass and bone density, and nausea. Taken together, these signs and symptoms are often called hypogonadism ("hypo" meaning low functioning and"gonadism" speaking to the testicles). Researchers estimate that the condition affects anywhere from two to six million men in the United States. Yet it's an underdiagnosed issue, with just about 5 percent of those 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 ailments and male reproductive and sexual problems. He has developed particular expertise 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 why he believes specialists should rethink the possible connection between testosterone-replacement treatment and prostate cancer.
Symptoms and diagnosisWhat signs and symptoms of low testosterone prompt that the typical man to find a doctor?
As a urologist, I tend to observe guys since they have sexual complaints. The main hallmark of low testosterone is reduced sexual desire or libido, but another may be erectile dysfunction, and some other guy 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 lesser quantity of fluid out of ejaculation, and a feeling of numbness in the penis when they see or experience something that would usually be arousing.
The more of the symptoms there are, the more probable it is that a man has low testosterone. Many physicians often dismiss those"soft symptoms" as a normal part of aging, however, they are often treatable and reversible by normalizing 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 lessen sex drive, such as the BPH drugs finasteride (Proscar) and dutasteride (Avodart). Those drugs may also decrease the quantity of the ejaculatory fluid, no question. However a reduction in orgasm intensity normally does not go together with treatment for BPH. Erectile dysfunction does not usually go together with it , though surely if somebody has less sex drive or less attention, it's more of a challenge to get a good erection.
How can you determine if or not a person is a candidate for testosterone-replacement therapy?
There are just two ways that we determine whether somebody has low 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 guys with the lowest testosterone have the most symptoms and men with maximum testosterone have the least. However, there are some guys who have reduced levels of testosterone in their blood and have no symptoms.
Looking at the biochemical amounts, The Endocrine Society* considers low testosterone to be a total testosterone level of less than 300 ng/dl, and I think that is a sensible guide. However, no one quite agrees on a few. It's not like 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.
| *Note: The Endocrine Society recommends clinical practice guidelines with recommendations for who should and should not receive testosterone therapy. Watch"Endocrine Society recommendations Click Here summarized." For a complete copy of the instructions, have a peek at this site log on to www.endo-society.org. |
Is total testosterone the ideal point to be measuring? Or should we be measuring something else?
This is just another area of confusion and great debate, 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 overall testosterone, or all of the testosterone in the human body. But about half of the testosterone that is circulating in the blood is not available to the cells.
The available part of overall testosterone is known as free testosterone, and it is readily available to the cells. Almost every lab has a blood test to measure free testosterone. Though it's just a little fraction of the total, the free testosterone level is a fairly good indicator of low testosterone. It's not perfect, but the correlation is greater compared to testosterone.
This professional organization urges testosterone treatment for men who have
- Low levels of testosterone in the blood (less than 300 ng/dl)
- symptoms of low testosterone.
Therapy Isn't Suggested for men who've
- Prostate or breast cancer
- a nodule on the prostate that can be felt during a DRE
- a PSA greater than 3 ng/ml without further evaluation
- a hematocrit greater than 50% or thick, viscous blood
- untreated obstructive sleep apnea
- severe lower urinary tract infections
- class III or why not try this out IV heart failure.
Do time daily, diet, or other elements affect testosterone levels?
For years, the recommendation was to receive a testosterone value early in the morning since levels begin to drop after 10 or even 11 a.m.. However, 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 within the course of this day. One reported no change in typical testosterone until after 2 p.m. Between 2 and 6 p.m., it went down by 13%, a modest sum, and probably insufficient to affect identification. Most guidelines nevertheless say it is important to perform the evaluation in the morning, however for men 40 and over, it probably doesn't matter much, as long as they get their blood drawn before 6 or 5 p.m.
There are a number of rather interesting findings about diet. For example, it seems that those who have a diet low in protein have lower testosterone levels than men who consume more protein. But diet has not been studied thoroughly enough to create any recommendations that are clear.
FormulationsExogenous vs. endogenous testosterone
In the following guide, testosterone-replacement treatment refers to the treatment of hypogonadism with exogenous testosterone -- testosterone that is manufactured outside the body. Based upon the formulation, treatment can cause skin irritation, breast enlargement and tenderness, sleep apnea, acne, reduced sperm count, increased red blood cell count, along with additional side effects.
In a recent prospective study, 36 hypogonadal men took a daily dose of clomiphene citrate for at least three months. Within four to six months, each one of the guys had heightened levels of testosteronenone reported any side effects throughout the year they were followed.
Since clomiphene citrate isn't approved by the FDA for use in males, little information exists regarding the long-term ramifications of carrying it (including the probability of developing prostate cancer) or whether it is more capable of boosting testosterone than exogenous formulations. But unlike adrenal gland, clomiphene citrate maintains -- and potentially enriches -- sperm production. This makes drugs such as 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 is 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.
Topical treatments help preserve a more uniform level of blood glucose. 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 on their skin. That restricts its use.
The most commonly used testosterone preparation from the United States -- and the one I start almost everyone off -- is a topical gel. There are just two brands: AndroGel and Testim. The gel comes in tiny tubes or in a unique dispenser, and you rub it on your shoulders or upper arms once a day. Based on my experience, it tends to be absorbed to great levels in about 80% to 85 percent of guys, but that leaves a significant number who don't consume sufficient for it to have a positive impact. [For specifics on several different formulations, see table ]
Are there any downsides to using gels? How much time does it require them to work?
Men who start using the implants need to come back in to have their own testosterone levels measured again to be sure they're absorbing the proper amount. Our target is that the mid to upper assortment of normal, which usually means approximately 500 to 600 ng/dl. The concentration of testosterone in blood really goes up quite quickly, within several doses. I usually measure it after 2 weeks, even although symptoms may not change for a month or two.