Erectile dysfunction
๐ Erectile Dysfunction (ED) = persistent inability to achieve or maintain an erection sufficient for satisfactory sexual performance.
It is common, impacts quality of life, and is often an early marker of systemic vascular disease.
๐ Definition
- ED = difficulty obtaining or maintaining an erection until completion of sexual activity, present โฅ3 months.
- Differentiate from decreased libido ๐ฝ, ejaculatory disorders ๐ฆ, and infertility ๐งฌ.
๐งฌ Physiology & Pathophysiology
- Normal erection requires:
- ๐ง Neural input: Parasympathetic S2โS4 โ nitric oxide โ smooth muscle relaxation.
- ๐ฉธ Vascular inflow: Cavernosal artery dilation โ โ blood filling.
- ๐ง Venous occlusion: Blood trapped within corpora cavernosa.
- ๐ช Hormones: Adequate testosterone.
- ED results from disruption in one or more: vascular (HTN, atherosclerosis), neurogenic (SCI, neuropathy), endocrine (hypogonadism, diabetes), psychogenic (anxiety, depression).
โ ๏ธ Causes of ED
| Category | Examples |
|---|
| ๐ง Psychogenic | Stress, performance anxiety, depression |
| ๐ฉธ Vascular | HTN, atherosclerosis, diabetes, smoking |
| ๐งฌ Neurological | MS, spinal cord injury, peripheral neuropathy |
| ๐ Endocrine | Hypogonadism, diabetes, thyroid disease |
| ๐ Drugs | SSRIs, TCAs, ฮฒ-blockers, alcohol, cannabis, cocaine |
| ๐ Mixed | Combination is very common |
๐ฉบ Clinical Assessment
- ๐ History: Onset (sudden = psychogenic, gradual = organic), nocturnal erections (present = psychogenic), libido, systemic illness, psychiatric history, substance use.
- ๐จโโ๏ธ Exam: Secondary sexual characteristics, genital exam (Peyronieโs, testicular size), pulses/BP (vascular disease), neuro exam (neuropathy).
๐ฌ Investigations
- ๐ฉธ Bloods: Fasting glucose/HbA1c, lipids, testosterone, prolactin, TFTs.
- โค๏ธ Cardiac risk assessment: ECG, exercise test if high vascular risk.
- ๐ฅ๏ธ Penile Doppler US: specialised, for surgical planning.
๐ Management
- ๐ฑ Lifestyle: Stop smoking ๐ญ, reduce alcohol ๐ท, weight loss โ๏ธ, exercise ๐.
- ๐ง Psychological: CBT, counselling, couples therapy.
- ๐ Pharmacological: PDE5 inhibitors (sildenafil, tadalafil, vardenafil) โ enhance NOโcGMP pathway โ erection.
โ Contraindicated with nitrates โ severe hypotension.
- ๐ ๏ธ Other therapies: Vacuum devices, intracavernosal alprostadil, intraurethral pellets, penile prosthesis (last-line).
๐ Prognosis
- Most men respond to PDE5 inhibitors or devices.
- Addressing lifestyle risks improves erectile & CV health.
- โก ED can precede coronary artery disease by 2โ5 years โ treat as a vascular warning sign.
โจ Clinical Pearls
- ๐ก Sudden ED + normal morning erections โ psychogenic.
- โก Gradual ED โ organic (usually vascular).
- โค๏ธ โAngina of the penisโ โ ED as sentinel for systemic vascular disease.
- โ PDE5 inhibitors + nitrates = fatal hypotension.
- ๐งโโ๏ธ Always check testosterone if libido low.
๐งโโ๏ธ Case Examples
Case 1:
๐จ A 52-year-old man with type 2 diabetes presents with gradual onset ED. He has reduced morning erections and mild peripheral neuropathy.
๐งช HbA1c 72 mmol/mol, fasting glucose elevated, testosterone normal.
โ
Management: optimise diabetes control, lifestyle changes, start PDE5 inhibitor, screen for cardiovascular risk.
Case 2:
๐จ A 40-year-old man reports sudden onset ED after starting sertraline for depression. He still has normal nocturnal/masturbatory erections.
๐ Exam and testosterone normal.
โ
Management: recognise drug-induced/psychogenic component, discuss alternative antidepressant, consider CBT, PDE5 inhibitor if needed.
๐ References
