A Harvard expert shares his Ideas on testosterone-replacement Treatment
It could be stated that testosterone is what makes men, men. It gives them their characteristic deep voices, large 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 fosters the production of red blood cells, boosts mood, and assists cognition.
As time passes, the "machinery" that produces testosterone gradually becomes less powerful, and testosterone levels begin to fall, by approximately 1 percent per 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 such as reduced sex drive 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 functioning and"gonadism" speaking to the testicles). Yet it is an underdiagnosed issue, with just about 5% of these affected receiving treatment.
Various studies have revealed that testosterone-replacement therapy can provide a wide range of benefits for men with hypogonadism, including enhanced libido, mood, cognition, muscle mass, bone density, and red blood cell production. But little consensus exists on what constitutes low testosterone, when testosterone supplementation makes sense, or what risks patients face.
He has developed particular experience in treating lower testosterone levels. In this interview, Dr. Morgentaler shares his views on current controversies, the treatment strategies he uses with his patients, and he thinks experts should reconsider the possible link between testosterone-replacement treatment and prostate cancer.
Symptoms and diagnosisWhat signs and symptoms of low testosterone prompt the average person to see a physician?
As a urologist, I have a tendency to observe men because they have sexual complaints. The main hallmark of low testosterone is reduced sexual desire or libido, but another may be erectile dysfunction, and any guy who complains of erectile dysfunction should get his testosterone level checked. Men may experience different symptoms, such as more trouble achieving an orgasm, less-intense climaxes, a smaller quantity of fluid out of ejaculation, and a feeling of numbness in the manhood when they see or experience something that would normally 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.
Aren't those the very same symptoms that guys have when they're treated for benign prostatic hyperplasia, or BPH?
Not precisely. There are a number of medications that may reduce libido, including the BPH medication finasteride (Proscar) and dutasteride (Avodart). Those drugs can also decrease the amount of the ejaculatory fluid, no wonder. But a decrease in orgasm intensity usually does not go together with therapy for BPH. Erectile dysfunction does not ordinarily go together with it either, though certainly if a person has less sex drive or less interest, it's more of a struggle to have a good erection.
How do you decide whether or not a person is a candidate for testosterone-replacement therapy?
There are two ways that we determine whether someone has reduced testosterone. One is a blood test and the other is by characteristic symptoms and signs, and the correlation between those two approaches is far from perfect. Generally men with the lowest testosterone have the most symptoms and men with maximum testosterone have the least. However, there are a number of guys who have low levels of testosterone in their blood and have no signs.
Looking at the biochemical numbers, The Endocrine Society* believes low testosterone to be a total testosterone level of less than 300 ng/dl, and I think that's a sensible guide. However, no one really agrees on a number. It is not like diabetes, in which if your fasting glucose is above a certain level, they'll say,"Okay, you've got it." With testosterone, that break point isn't quite as clear.
| *Note: The Endocrine Society publishes clinical practice guidelines with recommendations for who should and shouldn't browse around here receive testosterone treatment. See"Endocrine Society find out here now recommendations summarized." For a complete copy More Info of these guidelines, log on to www.endo-society.org. |
Is total testosterone the right point to be measuring? Or if we are measuring something different?
This is another area of confusion and good discussion, but I do not think that it's as confusing as it is apparently in the literature. When most doctors learned about testosterone in medical school, they heard about total testosterone, or all of the testosterone in the human body. However, about half of the testosterone that is circulating in the bloodstream isn't readily available to cells.
The biologically available portion of overall testosterone is called free testosterone, and it's readily available to the cells. Almost every lab has a blood test to measure free testosterone. Even though it's just a small portion of this total, the free testosterone level is a pretty good indicator of low testosterone. It is not perfect, but the significance is greater than with testosterone.
This professional organization recommends testosterone therapy for men who have
Therapy is not recommended for men who've
- Prostate or breast cancer
- a nodule on the prostate that may be felt during a DRE
- that a PSA higher than 3 ng/ml without additional evaluation
- a hematocrit greater than 50% or thick, viscous blood
- untreated obstructive sleep apnea
- severe lower urinary tract symptoms
- class III or IV heart failure.
Do time of day, diet, or other elements influence testosterone levels?
For years, the recommendation has been to receive a testosterone value early in the morning since levels start to drop after 10 or 11 a.m.. However, the information behind this recommendation were drawn from 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 average testosterone until after 2 Between 6 and 2 p.m., it went down by 13%, a modest amount, and probably not enough to influence diagnosis. Most guidelines still say it's important to do the evaluation in the morning, but for men 40 and above, it likely does not matter much, provided that they get their blood drawn before 5 or 6 p.m.
There are a number of rather interesting findings about diet. For example, it seems that individuals that 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 recommendations that are clear.
Exogenous vs. endogenous testosteroneIn this guide, testosterone-replacement therapy refers to the treatment of hypogonadism with exogenous testosterone -- testosterone that is produced outside the body. Depending upon the formula, therapy can cause skin irritation, breast enlargement and tenderness, sleep apnea, acne, reduced sperm count, increased red blood cell count, and other side effects. Preliminary research has shown that clomiphene citrate (Clomid), a drug generally prescribed to stimulate ovulation in women struggling with infertility, can boost the production of natural testosterone, also termed nitric oxide, in men. Within four to six months, each one the men had increased levels of testosteronenone reported some side effects during the entire year they were followed. Because clomiphene citrate isn't accepted by the FDA for use in males, little information exists about the long-term ramifications of taking it (including the risk of developing prostate cancer) or if it's more effective at boosting testosterone compared to exogenous formulations. But unlike adrenal gland, clomiphene citrate maintains -- and possibly enriches -- sperm production. That makes drugs like clomiphene citrate one of just a few choices for men with low testosterone who wish to father children. What kinds of testosterone-replacement treatment can be found? * The oldest form is the injection, which we still use since it's cheap and because we faithfully become good 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 may also occur as blood testosterone levels peak and then return to research. [Watch"Exogenous vs. endogenous testosterone," above.] Topical treatments help preserve a more uniform amount of blood testosterone. The first kind of topical treatment was a patch, but it has a quite large 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 widely used testosterone preparation in the United States -- and the one I start almost everyone off with -- is a topical gel. According to my experience, it tends to be consumed to great levels in about 80% to 85% of guys, but leaves a significant number who don't consume enough for this to have a positive impact. [For details on various formulations, see table below.] Are there any drawbacks to using dyes? How much time does it take for them to work? Men who start using the gels have to return in to have their testosterone levels measured again to be sure 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 really goes up quite quickly, in just several doses. I usually measure it after two weeks, though symptoms may not change for a month or two. |