Erectile dysfunction, often called impotence, is characterized by the inability to achieve or sustain an erection. Studies indicate that approximately 30 million men in the United States suffer from some form of impotence and that erectile dysfunction accounts for 500,000 visits to health-care providers each year, according to the Encyclopedia of Mental Disorders. In other words, erectile dysfunction is a common disorder, and the likelihood of experiencing some type of impotence increases significantly with age, notes the Encyclopedia of Mental Disorders.
Diseases
Diabetes causes circulatory problems that can cause erectile dysfunction, particularly if left untreated. Between 35 and 50 percent of men with diabetes have erectile dysfunction, says the National Institutes of Health. Additional health problems that can increase your risk of impotence include heart disease, enlarged prostate, multiple sclerosis, Parkinson's disease, kidney disease and diseases or injuries that damage pelvic nerves or the spinal cord, says the Mayo Clinic. It is important to consult a physician about erectile dysfunction, as impotence can be a symptom of serious health problems.
Lifestyle
Lifestyle choices can play a big part in erectile dysfunction, particularly habits that lead to high blood pressure and poor circulation. Lifestyle choices linked to erectile dysfunction include smoking, heavy drinking or drug use, being overweight and insufficient exercise, notes the National Institutes of Health. The Mayo Clinic suggests quitting smoking and developing a regular exercise routine to improve blood flow and overall health. Fatigue can also be a factor in impotence if a man is pushing himself too hard.
Psychological Factors
Although once thought to be largely psychological, impotence is now recognized as having a medical cause in most cases. In fact, 85 percent of erectile dysfunction cases are caused by medical or physical problems, says HealthCentral.com. But psychological problems, including anxiety and depression, can and do cause impotence.


