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 normal erections. It also boosts the production of red blood cells, boosts mood, and aids cognition.
As time passes, the "machinery" which makes testosterone slowly becomes less effective, and testosterone levels start to drop, by about 1% per year, starting in the 40s. As guys get into their 50s, 60s, and beyond, they might start to have signs and symptoms of low testosterone like lower sex drive 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" meaning low working and"gonadism" speaking to the testicles). Yet it is an underdiagnosed issue, with only about 5 percent of these affected receiving treatment.
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.
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 he believes experts should reconsider the potential link between testosterone-replacement therapy and prostate cancer.
Symptoms my response and you can try these out diagnosisWhat symptoms and signs of low testosterone prompt the typical person to see a physician?
As a urologist, I tend to see guys because they have sexual complaints. The primary hallmark of reduced testosterone is low 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, like more difficulty achieving an orgasm, less-intense orgasms, a much smaller amount of fluid out of ejaculation, and a feeling of numbness in the penis when they see or experience something which would usually be arousing.
The more of these symptoms there are, the more probable it is that a man has low testosterone. Many physicians often discount those"soft symptoms" as a normal part of aging, but they are often treatable and reversible by decreasing 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 lessen sex drive, including the BPH medication finasteride (Proscar) and dutasteride (Avodart). Those drugs may also decrease the amount of the ejaculatory fluid, no question. However a decrease in orgasm intensity normally does not go along with treatment for BPH. Erectile dysfunction does not ordinarily go together with it , though certainly if somebody has less sex drive or less interest, it's more of a struggle to have a fantastic erection.
How do you decide whether or not a man is a candidate for testosterone-replacement therapy?
There are just two ways that we determine whether someone has reduced testosterone. One is a blood test and the other one is by characteristic signs and symptoms, and the correlation between these two approaches is far from perfect. Generally guys with the lowest testosterone have the most symptoms and guys with highest testosterone have the least. But there are some men who have reduced levels of testosterone in their blood and have no symptoms.
Looking at the biochemical amounts, 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 is similar to 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.
| *Note: The Endocrine Society publishes clinical practice guidelines with recommendations for who should and shouldn't receive testosterone therapy. |
Is total testosterone the right thing to be measuring? Or if we are measuring something different?
This is just another area of confusion and good debate, but I don't think it's as confusing as it appears to be from the literature. When most physicians learned about testosterone in medical school, they learned about total testosterone, or all the testosterone in the human body. However, about half of their testosterone that is circulating in the blood isn't available to cells. It's tightly bound to a carrier molecule known as sex hormone--binding globulin, which we abbreviate as SHBG.
The available part of overall testosterone is called free testosterone, and it's readily available to the cells. Though it's just a small fraction of this overall, the free testosterone level is a pretty good indicator of low testosterone. It is not perfect, but the significance is greater compared to total testosterone.
This professional organization recommends testosterone therapy for men who have
- Low levels of testosterone in the blood (less than 300 ng/dl)
- symptoms of low testosterone.
Therapy Isn't recommended for men who have
- Breast or prostate cancer
- a nodule on the prostate which can be felt during a DRE
- that a PSA higher than 3 ng/ml without additional evaluation
- a hematocrit greater than 50 percent or thick, viscous blood
- untreated obstructive sleep apnea
- severe lower urinary tract symptoms
- class III or IV heart failure.
Do time daily, diet, or other factors influence testosterone levels?
For many years, the recommendation has been to receive a testosterone value early in the morning because levels start to fall after 10 or 11 a.m.. However, the data behind that recommendation were attracted to healthy young men. Two recent studies showed little change in blood glucose levels in men 40 and older within the course of this day. One reported no change in average testosterone till after 2 p.m. Between 6 and 2 p.m., it went down by 13%, a small sum, and probably insufficient to affect diagnosis. Most guidelines nevertheless say it's important to perform the test in the morning, however for men 40 and above, it likely doesn't matter much, provided that they get their blood drawn before 6 or 5 p.m.
There are some rather interesting findings about diet. For 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 article, testosterone-replacement therapy refers to the treatment of hypogonadism with adrenal gland -- testosterone that's produced outside the body. Depending upon the formulation, therapy can lead to skin irritation, breast enlargement and tenderness, sleep apnea, acne, decreased sperm count, increased red blood cell count, and additional side effects.
Within four to six months, all of the guys had heightened levels of testosterone; none reported some side effects throughout the year they were followed.
Because clomiphene citrate isn't approved by the FDA for use in men, little information exists regarding the long-term ramifications of taking it (including the probability of developing prostate cancer) or if it is more effective at boosting testosterone compared to exogenous formulas. But unlike exogenous testosterone, clomiphene citrate maintains -- and potentially enhances -- sperm production. This makes medication like clomiphene citrate one of only a few choices for men with low testosterone that wish to father children.
FormulationsWhat forms of testosterone-replacement treatment can be found? *
The earliest form is an injection, which we still use since it's inexpensive and since we faithfully become good testosterone levels in nearly everybody. The disadvantage is that a man should 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.
Topical therapies help maintain a more uniform level of blood testosterone. The first form of topical treatment has been a patch, but it has a quite high rate of skin irritation. In 1 study, as many as 40% of men who used the patch developed a reddish area in their skin. That limits its use.
The most commonly used testosterone preparation in the United States -- and the one I start almost everyone off with -- is a topical gel. Based on my experience, it tends to be absorbed to good levels in about 80% to 85% of men, but that leaves a substantial number who don't absorb enough for it to have a positive impact. [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 goal is the mid to upper assortment of normal, which usually means around 500 to 600 ng/dl. The concentration of testosterone in the blood actually goes up quite fast, in just several doses. I usually measure it after two weeks, though symptoms may not alter for a month or two.