Transcript ED - Audley Mills

ED
Dr Saqib Mahmud
MRCP(UK), MRCPS(Glasg), MRCGP
ED-inability to achieve/maintain an erection
sufficient for mutually satisfying intercourse
• Incidence- increase with age
• 39% men aged 40yrs, 67% age 70yrs
• Present worldwide prevalence>150 million
men, double in next 25yrs >300 million
men by 2025
• Previously thought of inorganic origin,
now believed that ED is increasingly due
to organic disease
Mechanism of erection
• Largely a vascular event
• In response to sexual stimuli, parasympathetic
•
nervous system dilates cavernosal arteries &
relaxes trabecular smooth muscle increased
blood flow filing sinusoidal spaces engorge
penis (tumescence) compress & stops venous
outflow maintaining the erection
Reverse of these events after ejaculation
sympathetic activity--.contraction of arteries &
trabecular smooth muscle--.venous outflow
decompression of venous channels
(detumescence)
Chemical pathways in penile erection
• Most important NO-induced cGMP pathway
• Endothelial cells release NO in response to
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sexual stimuli
NO increases cGMP, which relaxes the corpus
cavernosal smooth muscle leading to an erection
Detumescence occurs when cGMP is broken
down by an enzyme ‘’phosphodiesterase’’(PDE5)hence the role of PDE5 inhibitors in
maintaining the erection
causes
• Vascular-endothelial dysfunction,
atherosclerosis, htn, hypercholesterolemia
• Endocrine-DM, hypothyroidism,
hyperprolactinaemia, testosterone
deficiency, hormonal imbalance due to
hepatic & renal disease
• Neurological-MS, CVA, Parkinson’s,
Alzheimer’s, spinal cord & brain injuries
• Peyronie’s disease- rare inflammatory
condition->scaring of erectile tissue>painful erection
Drugs->200 commonly prescribed drugs can cause
or contribute to ED
• Beta-blockers
• Diuretics-BFZ, furosemide
• ACEI
• CCB
• LH-RH analogs
• Antiandrogens
• Benzodiazepines
• Alcohol
• Illicit drugs
Other causes of ED
• Pelvic trauma
• Radiotherapy
• Colorectal, prostate & bladder surgery
increases the risk of ED
• Vascular leak- veins unable to constrict
efficiently during erection
• Substance abuse- chronic use of cocaine,
marijuana, alcohol, steroids
• Excessive use of tobacco-nicotine in
tobacco causes contraction of small blood
vessels less flow to the region->ED
Psychological causes of ED
• Depression
• Anxiety
• Stress
• Performance anxiety– anxiety & stress
lead to increased production of
catecholamine which act as erection
inhibitors
Assessment – ED as a marker
Study of 980 men with ED found;
• 18% - undiagnosed HTN
• 16% - DM
• 15% - BPH
• 5% - IHD
• 4% - Ca Prostate
• 1% - Depression
b/w 39 & 64% of males with CVD suffer
from ED
Physical Assessment
• BP
• Femoral & peripheral pulses, femoral bruits –
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vascular abnormalities / PVD
Neurological exam – deep tendon reflexes,
bulbocavernosis reflex (gentle squeeze of
glans anal contraction), reduced sensationsacrum, perineum
Visual field defects – prolactinoma, pituitary
mass
Gynaecomastia – hyperprolactinaemia
Testicular atrophy- testosterone def,
hypogonadism
Assessment - contd
• Rectal exam – assessment of prostate &
sphincter tone
• PHQ-9 Questionnaire
• FBS
• U&Es, LFTs, TFTs
• Serum testosterone & SHBG, prolactin
Management of ED
• PDE5 inhibitors – sildenafil, tadalafil,
vardenafil
• Sildenafil (1998) - 25mg, 50mg,100mg
Taken 1hr before sex, effective up to 4 to
5 hrs, s/e - headache
• Tadalafil (2003) – 10mg, 20mg(PRN)
2.5mg, 5mg(once daily-2009)
Taken 30 minutes before sex, effective
up to 36hrs, s/e - dyspepsia, headache
contd
• Vardenafil(2003) – 5mg, 10mg, 20mg
Taken 25 – 60minutes before sex,
effective up to 4 – 5 hrs, s/e – headache,
flushing
When PDE5 inhibitors don’t work
Patient Education
• 81% do not take them correctly
• Adequate sexual stimulation necessary
• Food & alcohol delay & reduce absorption
• Some need 6-8 doses before an optimal
response occurs
• Psychotherapy integrated with
pharmacotherapy
Prescribing advice
• Switch drugs
• Optimize dose – increase to max
• Patients unresponsive to PRN Tadalafil,
consider once daily regime
• Combine with other drugs; intraurethral
alprostadil with PDE5 inhibitors or with
doxazocin (weak erectogenic agent) ideal
with BPH+HTN patients
Other treatments for ED
• MUSE – medicated urethral system for
erection, pallet of PGE1(alprostadil)
inserted in urethra 15min before sex,
lasts 30 to 60min
• Can be used up to twice daily
• s/e – penile pain, burning (32%)
• 43% efficacy compared to intracavernosal
route but less complications such as
priapism and penile fibrosis with injections
Vacuum constriction devices
• SOMACorrect Xtra, SOMAerect Response
II
• One time cost (£160 - £180/-)
• Efficacy – 92% regardless of underlying
cause of ED
• Time to erection onset- 90 to 120 seconds
• Time required to terminate erectin
<30seconds
• No systemic side effects compared to oral
Rx
Surgical treatment for ED
• Penile prosthesis – for patients who
probabaly have sufffered physical damage
to corpora, renndering other treatments
ineffective
• Vascular surgery – when ED is due to poor
arterial inflow or abnormal venous
drainage ( arterial revascularization,
ligation of venous incompetence)
• Results vary widely but usually poor
Testosterone therapy
• Only indicated in men whose loss of libido/
ED is due to hypogonadism or
documented low testosterone levels
• Testosterone deficiency is a rare cause of
ED
• Administered orally, i/m injections, skin
patches or implants