W12 Erectile Dysfunction (SW) Flashcards
What is the definition of erectile dysfunction?
- ED is defined as the persistent inability to attain and maintain an erection sufficient to permit satisfactory sexual performance.
- It is a symptom and not a disease and may be due to multiple underlying causes.
- The European Association of Urology (EAU) suggests that the terms ‘primary organic’ or ‘primary psychogenic’ are used to define the likely cause, as most cases are of mixed aetiology.
Causes of ED?
Erectile dysfunction is caused by various vascular, neuronal, hormonal, and metabolic factors, mediated by endothelial and smooth muscle dysfunction, as normal erectile function relies on arterial dilatation, smooth muscle relaxation, and veno-occlusion within the penile corpora
Organic causes
- Vasculogenic (most common) — cardiovascular disease (CVD), hypertension, peripheral arterial disease, hyperlipidaemia, type 1 and 2 diabetes mellitus, metabolic syndrome, smoking, obesity, major pelvic surgery (radical prostatectomy), or radiotherapy (to pelvis or retroperitoneum).
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Neurogenic (central) — degenerative disorders (e.g. MS, PD, and multiple system atrophy), stroke, spinal cord trauma or disease, or central nervous system (CNS) tumours.
Neurogenic (peripheral)— type 1 and 2 diabetes mellitus, chronic kidney disease, chronic liver disease, polyneuropathy, major surgery of the pelvis or retroperitoneum, or urethral surgery (for example, urethroplasty for urethral stricture).
Anatomical or structural — Peyronie’s disease, penile cancer, prostate cancer, congenital curvature of the penis, micropenis, hypospadias, epispadias, or phimosis. - Endocrine — type 1 and type 2 diabetes mellitus, metabolic syndrome, primary or secondary hypogonadism, hyperprolactinaemia, hyper- or hypothyroidism, Cushing’s disease, panhypopituitarism and multiple endocrine disorders, or hypopituitarism following traumatic brain injury.
Psychogenic causes? (2)
- Generalized — for example, due to lack of arousability and disorders of sexual intimacy.
- Situational — for example, due to partner- or performance-related issues, relationship problems (marital, extramarital, or new relationship), stress, depression, anxiety, post-traumatic stress disorder, or psychosis.
Some common medication can cause or worsen ED:
- Antihypertensives — beta-blockers, verapamil, methyldopa, and clonidine.
- Diuretics — spironolactone and thiazides.
- Antidepressants — tricyclics, monoamine oxidase inhibitors (MAOIs), selective serotonin reuptake inhibitors (SSRIs), lithium, and venlafaxine.
- Antiarrhythmic drugs — digoxin and amiodarone.
- Anticholinergics — pregabalin, gabapentin, and duloxetine.
- Antiepileptics — carbamazepine, topiramate, gabapentin, and pregabalin.
- Antipsychotics/tranquilizers — chlorpromazine, haloperidol, and phenothiazines.
- Hormones and hormone-modifying drugs — anti-androgens (such as cyproterone acetate); gonadotrophin-releasing hormone agonists (such as leuprorelin, goserelin); corticosteroids; 5-alpha reductase inhibitors (such as finasteride), oestrogens, and progesterone.
- Histamine (H2)-antagonists — cimetidine and ranitidine.
- Cytotoxic drugs — cyclophosphamide and methotrexate.
- Recreational drugs — alcohol, heroin, cocaine, cannabis, methadone, anabolic steroids, and opiates.
Risk factors for ED?:
- Similar to those for CVD in general: age, obesity, hypertension, hyperlipidaemia, diabetes, metabolic syndrome/NAFLD, sleep apnoea, BPH/LUTS.
- Lifestyle factors: lack or exercise and sedentary lifestyle, smoking, alcohol misuse, bicycle-riding for more than 3 hours a week.
Diagnosis:
What tests to diagnose ED?
- Explore psychosexual factors
- Medical history – CVD, hypertension, hyperlipidaemia, diabetes, medication, smoking/alcohol, LUTS
- Medical tests and investigations:
-HbA1c, TFT, lipids, U+E, PSA, testosterone
-BP, pulse, weight and BMI
-DRE
Prognosis:
- Psychogenic erectile dysfunction, post-traumatic arteriogenic erectile dysfunction in young men, and erectile dysfunction due to hormonal causes (e.g. hypogonadism or hyperprolactinaemia) may be cured with specialist treatment
- Drug-induced ED can be cured by stopping the offending drug
- ED following prostatectomy may be reversible depending on the nature of the surgery
- 60-65% of men with ED will be able to have sex using a PDE-5 inhibitor
Management of ED:
Non pharmacological?
address risk factors, e.g. weight loss, exercise, smoking cessation, alcohol reduction, reduce cycling(!)
optimise management of underlying diseases, e.g. hypertension, diabetes, hypercholesterolaemia
consider stopping contributory medicines
vacuum erection assistance devices*
Management of ED:
Pharamcological:
phosphodiesterase-5 (PDE) inhibitor, e.g. sildenafil, tadalafil, vardenafil, avanafil
alprostadil penile intracavernous injections*
medicated urethral system for erection (MES)*
PDE-5 inhibitors – contraindications
- Unstable angina
- Regular or intermittent use of nitrates in any form
- Hypotension (they tend to drop BP even further)
- Hx of non-arteritic anterior ischaemic optic neuropathy
- Recent hx of MI (within 90 days for tadalafil)
- Recent hx of stroke
- HF
- Uncontrolled arrhythmias
…more on NICE guidelines
PDE-5 inhibitors – counselling
- work by dilating the blood vessels supplying the penis
- allow erections to be achieved and maintained more easily but also requires sexual stimulation
- should be taken between 30 minutes and 1 hour before anticipated sexual activity
- best taken on empty stomach
- avoid alcohol
- if priapism occurs seek emergency medical help (prolonged erection)
Adverse effects of PDE5 inhibitors e.g. Sildenafil, Tadalafil, Vardenafil, Avamafil…
Headache
Flushing
Indigestion
Nasal congestion
Dizziness
Abnormal vision
Back pain
Muscle aching
Availability on NHS in Wales:
Who is eligible for treatment and what is the dose?
Usually one dose per week in men with:
* diabetes, MS, Parkinson’s disease, poliomyelitis, prostate cancer, severe pelvic injury, single gene neurological disease, spina bifida, spinal cord injury
* renal failure receiving dialysis
* surgery – prostatectomy, radical pelvic surgery, renal failure treated by transplant
* severe distress resulting from ED where the assessment has been made by a specialist service
In England generic sildenafil is not restricted
OTC brands of treatment? (2)
- Viagra connect- sildenafil
(pharmacy checklist before giving to pt
-check pt CV health, check concomitant meds use, check concomitant conditions) - Cialis together- tadalafil
