Erectile Dysfunction

Background

• Erectile dysfunction is the persistent inability to attain or maintain an erection satisfactory for sexual performance.
• It most often affects in men > 40 years old, and prevalence increases with age; erectile dysfunction is reported in 2%-12% of men aged 40-49 years, and 50%-100% of men > 70 years old.
• Causes of erectile dysfunction include:
  • vascular, neurogenic, endocrinologic, or psychogenic disorders
  • congenital or acquired anatomic anomalies, surgical complications, or trauma
  • respiratory, liver, or renal disease
  • medications or recreational substance use
• Erectile dysfunction shares some risk factors (modifiable and unmodifiable) with cardiovascular disease. Potentially treatable risk factors include smoking, lack of exercise, diabetes, hypertension, and obesity.

Evaluation

• Diagnose erectile dysfunction based on a history of inability to attain or maintain an erection satisfactory for sexual performance; psychosocial evaluation, physical exam, and routine blood testing are used to identify possible causes.
• Use a validated questionnaire for assessing the severity of erectile dysfunction, such as the International Index of Erectile Function-5 (IIEF-5) (Strong recommendation).
• Obtain a psychosocial, medical, and sexual history, including the patient's attitude and knowledge about sex; consider including the patient's partner (Strong recommendation).
• Perform a physical exam with attention to detecting penile deformities and signs of underlying medical conditions that may be associated with erectile dysfunction (Strong recommendation).
• Consider blood tests to help identify underlying medical conditions:
  • In all patients, fasting blood sugar or HbA1c, lipid profile, and morning total testosterone level is suggested (Weak recommendation).
  • If testosterone level is consistently low on ≥ 2 tests, measure luteinizing hormone (LH) and follicle-stimulating hormone (FSH) levels (Strong recommendation).
  • In selected patients where screening is warranted, consider thyroid function tests and/or prostate-specific antigen (PSA) testing.
• New-onset erectile dysfunction may be a marker for asymptomatic cardiovascular disease. Prior to treating erectile dysfunction or resuming sexual activity in men at risk for cardiovascular disease:
  • for intermediate-risk patients (symptomatic cardiovascular disease or ≥ 3 risk factors), perform cardiac stress testing.
  • for high-risk patients, refer to cardiologist for cardiac workup.
• Consider additional testing in select patients which may include nocturnal penile tumescence and rigidity (NPTR) test, duplex Doppler ultrasound of penis, intracavernous injection test, or invasive vascular imaging.

Management

• Initial management consists of identifying and treating a curable cause of erectile dysfunction, including any organic comorbidities and psychosexual dysfunctions (Strong recommendation).
• Address lifestyle changes and modify any reversible risk factors (Strong recommendation).
• If uncertain if sexual activity is safe (due to cardiac risk), manage based on risk assessment. If high risk, refer to cardiologist; if intermediate risk, obtain cardiac stress testing.
• Inform patient of relevant treatment options and their associated risks and benefits; choice of treatment should be made jointly by physician, patient, and partner, when possible, taking into consideration patient values, preferences, and expectations and experience and judgment of physician.
• Apply therapies in a stepwise fashion of increasing invasiveness with risks balanced against the likelihood of efficacy.
• Offer oral phosphodiesterase-5 (PDE-5) inhibitors as first-line therapy for erectile dysfunction in most men (Strong recommendation).
  • All PDE-5 inhibitors appear effective and have similar efficacy for treating erectile dysfunction, including in subgroups of patients with conditions such as cardiovascular disease, diabetes, prostate cancer, chronic kidney disease, and neurological and psychological conditions.
  • Approved PDE-5 inhibitors in the United States and worldwide include:
    • Sildenafil (Viagra): 50 mg (range 25-100 mg) orally 1 hour before intercourse
    • Tadalafil (Cialis): 10 mg (range 5-20 mg) orally before intercourse, or alternative daily dose of 2.5 mg (range 2.5-5 mg) orally once daily
    • Vardenafil (Levitra): 10 mg (range 2.5-20 mg) orally 1 hour before intercourse
    • Avanafil (Stendra): 100 mg (range 50-200 mg) orally 15-30 minutes before intercourse
  • PDE-5 inhibitors are contraindicated in patients receiving nitrates due to the risk of severe hypotension (Strong recommendation), but PDE-5 inhibitors are safe and effective in men with stable angina not taking nitrates.
  • Adverse effects that are reported to occur in > 2% of men taking sildenafil, tadalafil, or vardenafil include headache, flushing, dyspepsia, rhinitis, back pain, and color visual disturbances.
• Inform patients who have failed a trial with PDE-5 inhibitor therapy of benefits and risks of other therapies, including a different PDE-5 inhibitor, alprostadil intra-urethral suppositories, intracavernous drug injection, vacuum constriction devices, and penile prostheses (Strong recommendation).
  • Intraurethral alprostadil (prostaglandin E1), while generally less effective than intracavernous injection, may be considered as a second-line therapy for men who prefer a less invasive alternative (Weak recommendation).
  • Intracavernous injection therapy is a second-line treatment (Strong recommendation) which produces a predictable erection, usually within 10 minutes.
    • Intracavernous alprostadil may be more effective than intraurethral alprostadil.
    • If intracavernous alprostadil is ineffective or too painful, combination injection therapies that may be more effective or less painful include papaverine/phentolamine (bimix) and papaverine/phentolamine/alprostadil (trimix).
  • A vacuum erection device can be considered as a first-line therapy in well-informed older patients with infrequent sexual intercourse and comorbidity requiring noninvasive, nonpharmacologic management (Weak recommendation). Consider use in men who fail to improve with pharmacotherapy or who refuse intracavernous injection or penile prosthesis implantation.
  • Penile prosthesis implantation is considered a third-line therapy (Strong recommendation) and may be appropriate for men who fail to improve with pharmacotherapy or who prefer a permanent treatment modality.
    • Available classes of penile implants include inflatable (2- and 3-piece) and malleable prostheses.
    • The surgical approach can be penoscrotal or infrapubic.
• Management of erectile dysfunction that has specific causes may include:
  • psychosexual therapy for psychogenic erectile dysfunction, either alone or with another therapeutic approach; group psychotherapy may improve erectile function
  • correction of hormonal disorders, such as testosterone replacement for hypogonadism after other endocrine causes for testicular failure have been excluded; testosterone replacement is not indicated for treatment of erectile dysfunction in men with normal serum testosterone levels (Strong recommendation)
  • penile vascular surgery for pelvic or perineal trauma, or focal arterial occlusion in young men (Weak recommendation)
  • treatment of Peyronie disease with medications in early inflammatory phase or surgery in chronic fibrotic phase