What is erectile dysfunction?
Erectile dysfunction, or impotence, is the inability to achieve and sustain an erection suitable for sexual intercourse. The condition is not considered normal at any age. Premature ejaculation, infertility, or low sex drive are not the same as erectile dysfunction, though one or more of these conditions may be associated with it.
How serious a problem is erectile dysfunction?
It is estimated that erectile dysfunction affects about 1 in 10 adult males on a long-term basis. A much more common problem that affects most men at some point is the occasional failure to achieve an erection. Occasional failure can occur for a variety of reasons, such as from drinking too much alcohol or from extreme fatigue.
Failure to achieve an erection less than 20 percent of the time is not unusual and treatment is rarely needed. Failure more than 50 percent of the time generally means there is a psychological or physical problem (or combination of both) that requires treatment.
Is erectile dysfunction a normal part of aging?
No. ED doesn't have to be a part of getting older. While it is true that older men may need more stimulation (such as stroking and touching) to achieve an erection, they should still be able to get an erection and enjoy sex.
What causes ED?
In order to achieve an erection, three conditions must occur:
- the nerves to the penis must be functioning properly
- the blood circulation to the penis must be adequate
- there must be a stimulus from the brain
If there is something interfering with any or all of these conditions, a full erection will be prevented.
Diseases that commonly cause ED include:
- Vascular disease: Vascular diseases are those that affect the blood vessels. These diseases include atherosclerosis (hardening of the arteries), hypertension (high blood pressure), and high cholesterol. These diseases, which account for 70% of physical-related causes of ED, restrict blood flow to the heart, the brain, and--in the case of ED--to the penis. Atherosclerosis alone accounts for 50%-60% of ED cases in men over age 60.
- Diabetes: Diabetes can cause nerve and artery damage that can make achieving an erection difficult. Between 35% and 50% of men with diabetes experience ED.
- Kidney disease: Kidney disease can cause chemical changes that affect hormones, circulation, nerve function, and energy level. These changes can lower libido (sex drive) or sexual ability. Drugs used to treat kidney disease may also cause ED.
- Neurological (nerve and brain) diseases: The nervous system plays a vital part in achieving and maintaining an erection. It is common for men with conditions such as stroke, multiple sclerosis (MS), Alzheimer’s disease, Parkinson’s disease, and spinal cord injuries to experience ED. This is due to an interruption in the transmission of nerve impulses between the brain and the penis.
- Prostate cancer: Prostate cancer doesn’t cause ED on its own, but treatment for prostate cancer can lead to erectile problems.
Other possible causes of ED include:
- psychological factors, such as stress, depression, and performance anxiety
- injury to the penis
- chronic illness
- certain medications
- a condition called Peyronie's disease (scar tissue in the penis)
- operations for prostate, bladder, and colon cancer
- venous leak: If the veins in the penis cannot prevent blood from leaving the penis during an erection, an erection cannot be maintained. This is known as a venous leak, and can be a result of injury, disease, or stress.
- tobacco, alcohol, or drug use: All three of these substances can damage a person’s blood vessels and/or restrict blood flow to the penis, causing ED. Smoking in particular plays a large role in causing ED in people with atherosclerosis.
- prescription drugs: There are more than 200 types of prescription drugs that may cause ED.
What is cholesterol?
Cholesterol is a type of fat that circulates in your blood. Your body makes some cholesterol on its own, regardless of what you eat. Cholesterol also comes from the foods you eat.
What's so bad about cholesterol?
Your body produces more than enough cholesterol on its own to stay healthy. Most Americans eat far too much cholesterol and fat, which can raise blood cholesterol levels. High levels of cholesterol can lead to heart disease.
How much cholesterol is too much?
A healthy cholesterol level depends on a variety of factors, including:
- your level of HDL (good) cholesterol compared with your level of LDL (bad) cholesterol
- your total cholesterol
- your number of risk factors for heart disease
- your age and activity level
- your current health status
Excess LDL cholesterol in your blood gets deposited in arteries, the blood vessels that feed the heart and brain. These deposits can join with other substances to form plaque, a thick, hard deposit in the blood vessel that leads to atherosclerosis. Plaque can narrow the passageway inside the artery and pinch off the flow of blood to the heart muscle, and to the penis.
How can I lower my cholesterol?
Here are a few tips for lowering cholesterol:
- Eat fewer fats and fried foods. Choose non-fat and low-fat versions of foods, if available.
- When eating fats, select unsaturated fats. (Unsaturated fats are liquid at room temperature; vegetable oils, for example. Avoid tropical oils, such as palm and coconut oil and any fat that is solid at room temperature.)
- Choose fish and poultry more often than red meat.
- Limit total amount of meat, fish, poultry, and low-fat cheeses to 7 ounces or fewer each day.
- If you smoke, quit.
- Lose extra weight.
- Eat more soluble fiber. Good sources are fruits, beans, peas, and oats.
- Limit egg yolks to no more than three per week. (Egg whites are fat-free.)
What is the link between erectile dysfunction and heart disease?
There is a very strong link between erectile dysfunction and heart disease. Several studies have shown that if a man has ED, he has a greater risk of having heart disease. For instance, in one study, 57% of men who had bypass surgery and 64% of men hospitalized for a heart attack had had ED.
Having ED can predict that a man will probably have heart disease symptoms within five years. In fact, having ED is as much a risk factor for heart disease as a history of smoking or a family history of coronary artery disease.
How is erectile dysfunction treated?
The ED drugs sildenafil (Viagra), vardenafil (Levitra), and tadalafil (Cialis) work by enhancing the presence of nitric oxide in the cavernosal smooth muscle in the penis. This allows the smooth muscles to relax and increases the blood flow to the penis.
- Thomson IM, Tangen CM, Goodman PJ, et al. Erectile Dysfunction and Subsequent Cardiovascular Disease. JAMA. 2005;294(23):2996-3002.
- Böhm M, Baumhäkel M, Teo K, et al. Erectile Dysfunction Predicts Cardiovascular Events in High-Risk Patients Receiving Telmisartan, Ramipril, or Both. Circulation. 2010;121:1439-1446.
- National Kidney and Urologic Diseases Information Clearinghouse. Erectile dysfunction. kidney.niddk.nih.gov Accessed 4/27/2012.
- National Kidney and Urologic Diseases Information Clearinghouse. What I Need to Know about Erection Problems. kidney.niddk.nih.gov Accessed 4/27/2012.
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This information is provided by the Cleveland Clinic and is not intended to replace the medical advice of your doctor or health care provider. Please consult your health care provider for advice about a specific medical condition. This document was last reviewed on: 4/13/2012…#15029