Date: October 1st, 2000
Testosterone, the most important of the male sex hormones, has been both touted and blamed for the critical role it plays in making men men. It has been praised for building muscle, fueling a healthy libido and maintaining energy levels. It has also been faulted for making some men overly aggressive. But the level of testosterone peaks in a man's body in his 20s and gradually declines with age. Can it get too low and what happens if it does? Should he consider testosterone replacement therapy (TRT)? To find out more about this testosterone deficiency and its treatment, we spoke with Dr. Lisa Tenover, a geriatrician at Emory University who studies the effects of hormone replacement in men age 65 and older.
What Are the Symptoms of Testosterone Deficiency?
Physical symptoms include weakness, fatigue, reduced muscle and bone mass, impaired red blood cell production, and sexual dysfunction (low sperm production, diminished libido and impotence). Psychological symptoms include depression, anxiety, insomnia, memory impairment and reduced cognitive function.
Are All Older Men Affected?
Although testosterone levels decrease with age, some men will never become hormone deficient, according to Dr. Tenover. A man on the low end of the normal range can still have all the testosterone he needs. And unlike women, whose estrogen levels drop rapidly once they reach menopause, men experience a slow decline in testosterone, usually over a couple of decades, making symptoms difficult to detect. "We don't really know how many men are testosterone deficient," said Dr. Tenover. "It could be as low as 5 percent of men over the age of 65 or as high as 50 percent, depending on how you define testosterone deficiency. The normal range is quite wide, and there is a lot of variability between people. Testosterone is also secreted in pulses throughout the day, so depending on what time of day you test it, you could be measuring either the highest or lowest point."
What Can TRT Do?
Most general practitioners just don't treat testosterone deficiency right now, Dr. Tenover added. "It's not seen as a life-threatening problem and there are no hard and fast rules for diagnosing and treating it," she explained. However, a number of men are getting positive results with TRT in Dr. Tenover's studies. While it is not a fountain of youth—it won't prevent or smooth out wrinkles, or keep your hair from falling out-TRT can do the following:
- stabilize or increase bone density
- improve energy and mood
- enhance body composition by increasing muscle strength and reducing fat tissue
- maintain or restore sexual desire and performance
With results like that, it is no wonder that men are taking notice and volunteering for TRT studies such as the ones Dr. Tenover conducts at Emory University. Most of her patients, she said, are self-referrals.
What Do We Still Need to Learn?
"We're a lot further along than we were five years ago-when we weren't even sure if testosterone levels decreased with age-but we need a lot more data before we really understand the benefits and risks of testosterone replacement therapy," said Dr. Tenover. While short-term safety data (that is, data from the last 3-4 years) look good many questions remain. "We need a better test for measuring testosterone, better ways to select men for treatment, and more data on long-term safety and effectiveness," she said. "We're way behind where we are in studying estrogen replacement therapy in post-menopausal women. We need a large, multi-center clinical trial to give us the data we need."
What Can Men Do Now?
- Know your testosterone level. Men should have their levels checked when they're young to determine their "healthy" baseline level.
- Maintain a healthy lifestyle. Chronic illness, obesity, cigarette smoking and chronic alcohol consumption can lower testosterone levels significantly. So can some prescription medicines.
- Talk to your doctor. If you suspect that you might have a testosterone deficiency, talk to your primary care doctor. If your level is on the low end and you are experiencing symptoms, your primary care doctor can refer you to an endocrinologist for further testing and evaluation.
For men with a known testosterone deficiency, TRT may:
- improve energy and strength
- increase bone density
- enhance lean body mass
- decrease body fat
- improve mood
- revive interest in sex
- help fight depression
- condition and treatment are not well-understood
- no data on long-term effects
- treatment lowers both good (HDL) and bad (LDL) cholesterol, so patients with heart disease should be monitored closely
- can increase fluid retention
- can increase red blood cell count
- can increase tumor growth in patients with breast and prostate cancer
- causes testosterone levels to fluctuate, which could lead to aggressive, angry behavior and mood swings
- testosterone injections are painful and must be done every 2-3 weeks
- transdermal patches and gels can cause skin irritations