A Harvard Specialist shares his Ideas on testosterone-replacement Treatment
It might be said that testosterone is what makes men, guys. It gives them their characteristic deep voices, big muscles, and facial and body hair, distinguishing them from women. 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 assists cognition.
Over time, the "machinery" which produces testosterone gradually becomes less effective, and testosterone levels begin to drop, by about 1 percent per year, beginning in the 40s. As guys get in 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, decreased energy, decreased muscle mass and bone density, and nausea. Taken together, these signs and symptoms are often referred to as hypogonadism ("hypo" significance low functioning and"gonadism" speaking to the testicles). Yet it's an underdiagnosed problem, with only about 5 percent of those affected receiving treatment.
But little consensus exists about what constitutes low testosterone, when testosterone supplementation makes sense, or what risks patients face. 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 problems. He has developed specific expertise in treating lower testosterone levels. In this interview, Dr. Morgentaler shares his views on current controversies, the treatment plans he uses with his own patients, and why he believes experts should reconsider the potential link between testosterone-replacement treatment and prostate cancer.
Symptoms and diagnosisWhat signs and symptoms of low testosterone prompt that the average man to find a doctor?
As a urologist, I have a tendency to see men since they have sexual complaints. The primary hallmark of reduced testosterone is reduced sexual desire or libido, but another may be erectile dysfunction, and any man who complains of erectile dysfunction must get his testosterone level checked. Men may experience different symptoms, such as more trouble achieving an orgasm, less-intense climaxes, a lesser quantity of fluid out of ejaculation, and a sense of numbness in the manhood 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 these"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 men have when they are treated for benign prostatic hyperplasia, or BPH?
Not precisely. There are a number of drugs which may reduce libido, including the BPH drugs finasteride (Proscar) and dutasteride (Avodart). Those drugs may also reduce the quantity of the ejaculatory fluid, no question. But a decrease in orgasm intensity normally does not go along with treatment for BPH. Erectile dysfunction does not ordinarily go together with it either, though certainly if somebody has less sex drive or less attention, it is more of a struggle to get a good erection.
How do you decide if or not a man is a candidate for testosterone-replacement therapy?
There are two ways 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 these two approaches is far from perfect. Generally men with the lowest testosterone have the most symptoms and men with maximum testosterone possess the least. However, there are a number of guys who have low levels of testosterone in their blood and have no symptoms.
Looking purely at the biochemical numbers, The Endocrine Society* believes low testosterone for a entire testosterone level of less than 300 ng/dl, and I believe that is a sensible guide. However, no one really agrees on a few. It's not like diabetes, where if your fasting glucose is above a certain level, they'll say,"Okay, you've got it." With testosterone, that break point is not quite as clear.
| *Note: The Endocrine Society publishes clinical practice guidelines with recommendations for who should and shouldn't anonymous receive testosterone therapy. visite site For a complete copy of these instructions, log on to www.endo-society.org. |
Is total testosterone the right thing to be measuring? Or should we be measuring something else?
Well, this is another area of confusion and great debate, but I do not think that it's as confusing as it is apparently from 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 is circulating in the bloodstream is not available to the cells. It's tightly bound to a carrier molecule called sex hormone--binding globulin, which we abbreviate as SHBG.
The available part of total testosterone is called free testosterone, and it is readily available to cells. Almost every laboratory has a blood test to measure free testosterone. Though it's just a little portion of this total, the free testosterone level is a pretty good indicator of low testosterone. It's not ideal, but the significance is greater compared to total testosterone.
This professional organization urges testosterone therapy for men who have both
- Low levels of testosterone in the blood (less than 300 ng/dl)
- symptoms of low testosterone.
Therapy is not recommended for men who've
- Breast or prostate cancer
- a nodule on the prostate which can be felt during a DRE
- 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 infections
- class III or IV heart failure.
Do time of day, diet, or other elements influence testosterone levels?
For many years, the recommendation has been to get a testosterone value early in the morning since levels start to drop after 10 or even 11 a.m.. But the data behind that recommendation were drawn from healthy young men. Two recent studies showed little change in blood glucose levels in men 40 and mature over 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 percent, a modest sum, and probably insufficient to influence identification. Most guidelines nevertheless say it's important to perform the test in the morning, however for men 40 and above, it probably does not matter much, as long as they obtain their blood drawn before 5 or 6 p.m.
There are some rather interesting findings about diet. By way of example, it seems that individuals that have a diet low in protein have lower testosterone levels than males who consume more protein. But diet has not been studied thoroughly enough to create any recommendations that are clear.
Within the following article, testosterone-replacement treatment refers to the treatment of hypogonadism with adrenal gland -- testosterone that is produced outside the body. Depending upon the formulation, therapy can cause skin irritation, breast tenderness and enlargement, sleep apnea, acne, reduced sperm count, increased red blood cell count, along with additional side effects.
At a recent prospective study, 36 hypogonadal men took a daily dose of clomiphene citrate for at least three months. Within four to six months, all the men had increased levels of testosterone; none reported some side effects throughout the year they had been followed.
Since clomiphene citrate is not accepted by the FDA for use in males, little information exists about the long-term ramifications of carrying it (including the risk of developing prostate cancer) or if it is more effective at boosting testosterone than exogenous formulas. But unlike exogenous testosterone, clomiphene citrate preserves -- and potentially enhances -- sperm production. That makes medication such as clomiphene citrate one of only a few choices for men with low testosterone that wish to father children.
FormulationsWhat kinds of testosterone-replacement treatment are available? *
The oldest form is the injection, which we use since it is cheap and because we reliably get fantastic testosterone levels in almost everybody. The drawback 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 maintain a more uniform level of blood testosterone. The first kind of topical treatment has been a patch, but it has a quite high rate of skin irritation. In one study, as many as 40% of men who used the patch developed a red area on their skin. That limits its usage.
The most widely used testosterone preparation from the United States -- and also the one I begin almost everyone off with -- is a topical gel. According to my experience, it has a tendency to be absorbed to good levels in about 80% to 85% of men, but that leaves a substantial number who don't consume sufficient for this to have a favorable impact. [For details on several different 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 come back in to have their testosterone levels measured again to make sure they are absorbing the proper quantity. Our goal is that the mid to upper assortment of normal, which generally means approximately 500 to 600 ng/dl. The concentration of testosterone in blood actually goes up quite quickly, within a few doses. I usually measure it after two weeks, although symptoms may not alter for a month or two.