Erectile dysfunction

Erectile dysfunction (ED) is the persistent inability to achieve and/or maintain a sufficient erection. It usually causes significant psychosexual morbidity, decreased self-esteem, anxiety, and depression, which might worsen the ED, causing an evil cycle.

Epidemiology

Affects 50% of men aged 40 – 70
Prevalence increases with age

Physiological erection

Flaccid penis
- Sympathetic nervous system predominates
- Cavernous smooth muscle is contracted
- Artery is vasoconstricted
Erect penis
- Parasympathetic nervous system predominates
- Cavernous smooth muscle relaxes
- Artery is vasodilated

Diagnosis and evaluation

Diagnosis is clinical
Anamnesis
- International Index of Erectile Function (IIEF)
Physical examination
- Hypogonadism
- Neurological disease
- Vascular disease
Labs
- Testosterone
- CVD risk factors
Nocturnal penile tumescence
- Erections physiologically occur during the night
- This test monitors the penis for erections during the night
  - If erections -> most likely psychogenic ED
  - If no erections -> most likely organic ED

Organic erectile dysfunction

Due to vasculogenic, neurologic, hormonal, or cavernosal abnormalities
Often co-exists with cardiovascular disease
- ED can be an early manifestation of CVD
Etiology
- Hypertension
- Diabetes
- Cardiovascular disease
- Smoking
- Alcohol
- Neurologic disease
- SSRIs
- Radical prostatectomy
- Pelvic injury

Psychogenic erectile dysfunction

Due to central inhibition of the erectile mechanism
Etiology
- Depression
- Anxiety
- Relationship issues
- Stress

Mixed type erectile dysfunction

Features of both organic and psychogenic ED

Treatment

Psychotherapy
First line
- PDE5 inhibitors
  - Sildenafil
  - Vardenafil
  - Tadalafil
  - Contraindicated in patients who take nitrates or other NO-donor drugs
- Vacuum tumescence device
  - Vacuum tube creates negative pressure around the penis
Second line therapy
- Intracavernous injection
- Intraurethral insertion of pellet
- Alprostadil
Third line
- Penile prosthesis implantation