Andrology [ Erectile dysfunction ]
( Lecture )Goals and Objectives
Define erectile dysfunction (ED) Discuss the most common causes of ED Review a practical evaluation of men with ED Review the treatment options Provide suggestions for urologic referralWhat is ED?
ED is the inability to achieve and maintain an erection adequate for intercourse to the mutual satisfaction of the man and his partner. Remember, both partners in a relationship are affected.Incidence
20-30 million American men suffer ED Age dependent 2% men age <40 years 25% men age 65 75% men >75 years Not a necessary occurrence of the aging processHow Does an Erection Occur?
The brain controls all sexual functions, from perceiving arousal to initiating and controlling the psychological, hormonal, nerve, and blood flow changes that lead to an erection. Hormones, including testosterone, control the male sex driveHow Does an Erection Occur? (cont.)
Nerve impulses relay signals of arousal and sensation to and from the penis Arteries deliver extra blood to the penis that causes it to stiffen. Veins then drain the blood out of the penis after intercourse.
Physical or Psychological Stimuli Results
Sacral parasympathetics (S2,3,4) stimulation to the penile nerves Dilation of the penile arteries Relaxation of the smooth muscle in the corporal bodies of the penis Decrease venous outflowAn Erection Requires a Coordinated Interaction of Multiple Organ Systems
Psychological Endocrine Vascular NeurologicMechanism of Smooth Muscle Relaxation
Release of Neurotransmitters-nitric oxide Conversion of GTP to cGMP - erection Breakdown of cGMP by PDE type 5 - detumesenceCause of ED
Psychogenic Causes: Anxiety Depression Fatigue Guilt Stress Marital Discord Excessive alcohol consumptionCauses of ED
Organic Causes Cardiovascular disease Diabetes mellitus Surgery on colon, bladder, prostate Neurologic causes (lumbar disc, MS, CVA) Priapism Hormonal deficiencyCauses of ED
Hormone Deficiency End Organ Failure Blockage of Blood Vessels Venous LeakCauses of ED
Spinal cord injuries: 5% - 80% Pelvic and urogenital surgery and radiation Substance abuse Alcohol: >600ml/wk Smoking amplifies other risk factors Medications may be responsible for ~25% of cases of ED Bicycle ridingCauses of ED
Medication: Most common cause of ED in men >50 Many men are polymedicated Also have co-morbid conditionsCauses of ED
Medications (cont.) Anti-hypertensive drugs All capable Common: thiazides and beta blockers Uncommon: calcium channel blockers, alpha-adrenergic blockers, and ACE inhibitorsCauses of ED
Medications (cont.) CNS drugs: Antidepressants, tricyclics, SSRIs Tranquilizers Sedatives Analgesics H1 and H2 receptor blockersCauses of ED
Medications (cont.) Anticholinergics LHRH agonists (Lupron, Zolladex) Alcohol Tobacco Drug abuse Estrogens, KetoconazoleA Practical Evaluation of Men with ED Basic evaluation
Medical History Cardiovascular history Endocrine history Sexual history/questionnaireA Practical Evaluation of Men with ED Basic evaluation (cont.)
Physical exam: Focused neurovascular exam Size of testis DRE Lab tests UA Testosterone, CMP, Lipid panel PSA in men >50 yearsA Practical Evaluation of Men with ED Sexual History
Premature ejaculation Retarded ejaculation Painful intercourse Anorgasmia Decreased Libido Dissatisfaction with sex lifeA Practical Evaluation of Men with ED Sexual History (cont.)
Do you have any problems with intimacy with your partner? Do you have early morning erections? Do you have erections with self-stimulation? Are you able to consistently obtain and maintain an erection sufficient for sexual intimacy? Does it hurt to have an erection or intercourse?A Practical Evaluation of Men with ED Sexual History (cont.)
Do you ejaculation sooner than you would like? Does it take too long to reach an orgasm? Do you fail to reach an orgasm? Did your erection problems start suddenly or over time?A Practical Evaluation of Men with ED Questionaire (cont.)
During sexual intercourse, how often were you able to maintain your erection after you had penetrated your partner? During sexual intercourse, how difficult was it to maintain your erection to completion of intercourse? When you attempted sexual intercourse, how often was it satisfactory for you?A Practical Evaluation of Men with ED Differentiating Psychogenic from Organic ED
Psychogenic Impotence: Younger patient (<40) Preservation of morning erections and nocturnal erections Achieve erection with masturbation May be partner-specific Often sudden onsetA Practical Evaluation of Men with ED Differentiating Psychogenic from Organic ED
Organic ED: Gradual deterioration Decrease in morning erections and nocturnal erections No erections with masturbation No loss of libido Presence of co-morbid conditionsA Practical Evaluation of Men with ED Physical Examination
Blood pressureExamine penis (R/O Peyronie’s disease)Determine size and consistency of testesDigital rectal examFocused vascular exam/peripheral pulsesFocused neurologic examA Practical Evaluation of Men with ED Laboratory Tests
UA (glycosuria) – Fasting if elevatedPSA in men over 50Testosterone (best to draw in A.M.)Prolactin, Thyroid function, Lipid profile, Liver function, CreatinineA Practical Evaluation of Men with ED Other Tests
NPT – Nocturnal Penile Tumescence TestPenile dopplerInjection of vasoactive drugsNEVA (Nocturnal Electobioimpedance Volumetric Assessment)Treatment Options Goal directed therapy4
Find out what the patient wants Try to tailor the treatment to the patients needs and wants Etiology rarely affects treatment choice for the patient 4 Lue TF, World J. Urol 8:67,1990Treatment Options
Nonpharmacologic Non-invasive Minimally invasive Invasive Counseling and/or sex therapy
Treatment Options
Oral medications - Viagra, Levitra, Cialis Urethral suppositories (MUSE) Injection therapy - Caverject, Trimix, Bimix Vacuum constriction device Surgery Sex therapyCounseling and/or Sex Therapy
Rule out depression Try oral medication in patient with psychogenic impotence Refer to sex therapist or psychiatrist for sever psychopathologyNonpharmacologic Treatment Options
Lifestyle changes: Reduce fat and cholesterol in diet Decrease or limit alcohol consumption Eliminate tobacco use and substance abuse Weight loss if appropriate Regular exerciseIdeal Medication for Treatment of ED
Effective Available on demand Free of toxicity and side effects Easy to administer InexpensiveMedication (Viagra, Levitra, Cialis)
Mechanism of Action: PDE inhibitor and increases the cGMP that promotes and sustains smooth muscle relaxationMedication (PDE Inhibitors)
Indications: Psychogenic ED Mild vasculogenic ED Neurogenic ED Side effects from medication(s) patient is already takingMedication (PDE Inhibitors)
Side effects: Headache Flushing Dyspepsia Nasal congestion Visual disturbances PriapismMedication (PDE Inhibitors)
Contraindications: Organic Nitrites: Oral Sublingual Severe cardiac disease Obtain stress testingMedication (Yohimbine, Yocon, Erex, Yohimex)
Alpha 2 andrenoreceptor antagonist Dose: 5.4 mg TID Results: ~20% (same as placebo) Side effects: increase blood pressure, tachycardia, anxietyMedication Trazodone(Desyrel)
Anti-depressant associated with priapism Mechanism of action nor fully understood Nor FDA approved for ED Side effects: drowsiness, dry mouth, sedation, priapismMedication Apomorphine (Spontane)
Dopaminergic mechanism with hypothalamic activity Sublingual administration 64% to 67% response rate with ED Side effects: nausea, sweating, hypotension, yawning Awaiting FDA approval
Medication Phentolamine (Vasomax)
Alpha-blocker Relaxes smooth muscle tissue 40% efficacy in mild organic ED Side effects: nasal congestion, tachycardia, dizziness, hypotension Awaiting FDA approvalMedication Side effects
Discontinue tobacco, alcohol, and abusive drugs Alter dosage of drugs with ED side effects Change to another class of drugsTransurethral Therapy Alprostadil - MUSE
Mechanism of Action: vasodilator Administration: 125, 250, 500. 1000ug Insert in the urethra Erection occurs 10-15 minutes later Erection lasts 30-45 minutes Results: 10-65% Side effects: Pain, bleeding, priapism (<3%)Penile Injection Therapy Caverject, Edex, Tri/Bi-Mix
Mechanism of action: smooth muscle vasodilator Administration: 10, 20, 40ug Inject directly into corporeal bodies of the penis Results: 70%-90% Dropout rates: 25%-60% Side effects: pain (36%), priapism (4%), fibrosisAndrogen Replacement Therapy
Indications: hypogonadism (<285ng/dl)Avoid oral estrogens-increase LFTsInjectable – 200mg testosterone (cypionate, enathate, propionate), q2-3 weeksTransdermalPatchgelAndrogen Replacement Therapy
Avoid in patients with prostate or breast cancer Slight increase risk of BPH Monitor all patients with annual DRE and PSA