Erectile Dysfunction as Warning Sign
Impotence isn't a deadly disease, but it can signal other deadly health problems.
Running Low on Testosterone
In addition to healthy blood circulation, the male sex hormone testosterone is important for erections and for sex drive. Men with erectile dysfunction may have low testosterone levels.
"Most of us think that one of the measurements one must do when you have a patient with newly diagnosed [erectile dysfunction] is look at testosterone levels," says Glenn Cunningham, MD, spokesman for the Endocrine Society and a professor at Baylor College of Medicine in Houston.
Many things can cause testosterone levels to be low, such as problems with the pituitary gland, which regulates the production of the sex hormone; thyroid abnormalities; liver problems; and abnormalities within the testes themselves. So if you're unable to get an adequate erection, it's possible that something is causing trouble with your body's testosterone production.
Most commonly, however, low testosterone is a result of aging. "[Male sex hormone] deficiency occurs with greater frequency in older-aged men," Cunningham says, but doctors don't know exactly why. "There are theories, but it's not well understood at this point."
If low testosterone is the only cause of a man's erectile dysfunction, it can be treated with testosterone replacement therapy.
As with all bodily functions, erections depend on signals from the brain that say when to start and when to stop. The inability to get an erection can sometimes result from a problem with the nerves carrying signals from the brain to the penis.
Erectile dysfunction may be a sign of undiagnosed or poorly managed diabetes. People with diabetes who don't keep their blood sugar levels under control can develop nerve damage (neuropathy). Often it's the nerves of the extremities, such as the hands and feet, that are damaged. But the genitals can be affected, too.
According to the National Institute of Diabetes & Digestive & Kidney Diseases, it's estimated that about one-half of all people with diabetes have some kind of neuropathy. It becomes more common in those who are older, overweight, and those with high blood pressure.
Besides diabetes, which is very common in the U.S. today, there are other, somewhat rarer things that affect the nervous system and can in turn cause erectile dysfunction.
"I see a lot of HIV patients that have erectile dysfunction, which is due to neuropathy," Sharlip says. "The virus causes neuropathy, and the antiviral agents that are used for treatment also themselves cause neuropathy."
Multiple sclerosis and spinal cord injuries are diseases of the nervous system that can cause impotence, although impotence is not one of the main symptoms of either disease.
Sometimes men who abuse alcohol and drugs that depress the central nervous system may find themselves unable to achieve erections, too.
About 90% of the time, the cause of erectile dysfunction is physical. But erectile dysfunction can also be caused by psychological problems such as stress or performance anxiety. Men whose erectile dysfunction is mainly a psychological problem are able to get an adequate erection but not when they want to.
The classic test to find out whether the problem is psychological or physical is to measure "nocturnal tumescence." This involves wrapping a strip of paper or tape around the flaccid penis at night. If the strip is broken in the morning, an erection likely occurred during sleep and impotence is most likely a psychological one.
When the problem is psychological, the underlying depression or anxiety is what should be treated.