Description

• Erectile dysfunction: The consistent or recurrent inability to acquire or sustain an erection of sufficient rigidity and duration for sexual intercourse.
• In the past, erectile dysfunction was assumed to be a symptom of the aging process in men, but it can result from concurrent medical conditions of the patient or from medications that patients may be taking to treat those conditions.
• Sexual problems are frequent among older men and have a detrimental effect on their quality of life but are infrequently discussed with their physicians (1).
• Synonym(s): Impotence

ALERT
When ED occurs in a younger man, it is associated with a significantly increased risk of future cardiac events (2).

Epidemiology

Incidence
It is estimated that over 600,000 new cases of erectile dysfunction will be diagnosed annually in the US, although this may be an underestimation of the true incidence, as erectile dysfunction is vastly underreported.

• 52% in men age 40–70 years
• Age-related increase ranging from 12.4% in men age 40–49 years up to 46.6% in men age 50–69 years

Risk Factors

• Advancing age
• Cardiovascular disease
• Diabetes mellitus
• Metabolic syndrome
• Cigarette smoking
• Urologic surgery, radiation, trauma/injury to pelvic area or spinal cord
• Medications that induce erectile dysfunction
• Central neurologic and endocrinologic conditions
• Substance abuse
• Psychological conditions: Stress, anxiety, or depression

Genetics
Rarely related to chromosomal disorders

General Prevention

The 2 best ways to prevent erectile dysfunction is by:

• Making healthy lifestyle choices by exercising regularly, eating well-balanced meals, and limiting alcohol and avoiding smoking
• Treating existing health problems and working with your patients to manage diabetes, heart disease, and other chronic problems

Pathophysiology

• Erectile dysfunction is a neurovascular event:
  • With stimulation, there is release of nitrous oxide, which increases production of cGMP.
  • This leads to relaxation of cavernous smooth muscle, leading to increased blood flow to penis.
  • As cavernosal sinusoids distend with blood, there is passive compression of subtunical veins, which decreases venous outflow and this leads to an erection.
• Alterations in any of these events leads to erectile dysfunction.

Etiology

• Erectile dysfunction may result from problems with systems required for normal penile erection:
  • Vascular: Diseases that compromise blood flow:
    • Peripheral vascular disease, arteriosclerosis, essential hypertension
  • Neurologic: Diseases that impair nerve conduction to brain or penile vasculature:
    • Spinal cord injury, stroke, diabetes
  • Endocrine: Diseases associated with changes in testosterone, luteinizing hormone, prolactin levels
  • Psychological: Patients suffering from malaise, depression, performance anxiety
• Social habits such as smoking or excessive alcohol intake
• Medications may cause erectile dysfunction.
• Structural injury or trauma (bicycling accident)

Geriatric Considerations
Aging alone is not a cause.

Commonly Associated Conditions

• Cardiovascular disease:
  • Men with erectile dysfunction have a greater likelihood of having angina, myocardial infarction, stroke, transient ischemic attack, congestive heart failure, or cardiac arrhythmia compared to men without erectile dysfunction (3).
• Diabetes
• Psychiatric disorders