Erectile dysfunction (ED) is common, affecting over 150 million men worldwide. It is a marker for other neurovascular complications in diabetes. The causes of ED include vascular, neurological, endocrine, and psychological factors. Treatments include oral phosphodiesterase type 5 inhibitors, vacuum devices, intracavernosal injections, testosterone replacement, and psychosexual counseling. Managing associated conditions and hormonal deficiencies can effectively treat ED.

1. Erectile dysfunction – a growing problem Dr Thomas Fox Endocrine SpR Royal Cornwall Hospital, Truro

2. Erectile Dysfunction (ED) Definition Epidemiology Aetiology Clinical features History Examination Investigation Treatment

3. Definition The consistent inability to obtain and maintain penile erection sufficient to complete satisfactory sexual performance

4. Epidemiology Estimated to affect 152m men worldwide Non-diabetic men 0.1-18.4% prevalence In a study of 541 diabetic males 35% in diabetic men 5.7% in 20-24 year olds 52.4% in 55-59 years olds ED is a growing problem Massachusetts Male Aging Study estimate an 11% world increase by 2015

5. Aetiology Vascular Neurological Endocrine Psychological Pharmacological Penile tissue abnormalities Others

6. Vascular Arterial insufficiency Endothelial dysfunction (up to 95%) Discrete lesions Venous leakage Failure of venule constriction

7. Neurological Damage to autonomic nervous system Predominant parasympathetic damage

8. Endocrine Hypogonadism Most commonly primary testosterone deficiency Secondary hypogonadism Hypothyroidism Hyperprolactinaemia

9. Other causes of ED Penile Balinitis Phymosis Penile finrosis Tumours Trauma Pharmacoloical

10. Clinical features History Examination

11. History Patient’s description of the problem Patient’s and partners expectations Duration Speed of onset Intermittent/progressive? History of sexual partners Nocturnal erections? Libido

12. PMH Glycaemic control Vascular/neurological disease Urological PSH and trauma DH Anti-hypertensives Androgen antagonists Sedatives Drugs that cause hyperprolactinaemia (phenolthiazides) Alcohol Psychological assessment

13. Examination General Vascular Neurological Genitalia DRE

14. Investigation Diabetic/vascular Endocrine 9am Testosterone Thyroid function tests Pituitary hormones (LH,FSH,PRL) Imaging

15. Management Multidisciplinary approach Involvement of partner Couples expectations and desires

16. Oral therapies Phosphodiesterase V inhibitors Sildenafl ( Viagra) 4hr Tadalafil ( Cialis) 17hrs Vardenafil (Levita) 4 hrs Side effects flushing, headache and GI disturbance Contraindications - nitrates

18. Efficacy of PDE-V inhibitors Hundreds of studies internauinally Improved erections and increased successful episodes of sexual intercourse vs placebo (15 RCTs)

19. Levinson et al 1998 254 males over 18 with clinical diagnosis of ED for >6 months Randomised double blind placebo controlled trial Primary end-point Index of Erectile Function (IEF) Variable dose 25mg-100mg adjusted by the patients

20. IEF Q3 ability to obtain erection IEF Q4 ability to maintain erection p<0.0001 IEF7 satisfaction with therapy

22. Improved erections at 12 weeks p<0.0001 % successful sexual attempts in last 4 weeks p<0.0001

23. PDE V inhibitor prescribing Following conditions DM PD, MS, polyiomyelitis Pinal cord injuries, spina bifida Radical prostatectomy Trial of 8 doses with dose titration before classifying as failure of treatment Once correct dose achieved then can prescribe 1 tablet per week

24. Vacuum devices Can improve erection Messy and user dependent Satisfaction varies 35-80%

25. Intracavernosal injections Intracavernosal injections with prostaglandins Alprostadil (prostaglandin E1) One large RCT found increased rate of satisfactory erections when alprostadil injected compared to placebo Side effects – pain, priapism

26. Testosterone replacement Improves erectile function and libido Preparations Topical (testim gel) Im testosterone Long-acting depots

27. Testosterone replacement improving diabetes? Kapoor et al 2006 Small double-blind placebo controlled crossover trial (n=24) T II DM with testosterone deficiency (10 on insulin therapy) 3 months treatment with testosterone (200mg im 2-weekly)replacement and 3 months with placebo (1 month washout) Endpoints – fasting glucose, HbA1C and HOMA in non-insulin treated subjects (homeostatic model index) Secondary endpoints waist circumference, BP and lipids

28. Results HbA1C reduced by 0.37% (p=0.03) Fasting glucose reduced by 1.58mmol/L(p=0.03) HOMA index reduced 1.73 (p=0.02) Waist circumference reduced 1.73cm (p=0.03) Total cholesterol reduced 0.4mmol/L (p=0.03) No effect on BP Conclusions Testosterone replacement can improve T II diabetic control

29. Intraurethral alprostadil Effective but requires sufficient training required

30. Penile implant Inflatable Malleable

31. Psychosexual counselling Talking therapies for men and couples

32. Summary ED Common Marker for other forms of neurovascular complications in diabetes Psychologically damaging Treatable Treat associated hormonal deficiencies

33. References Efficacy and safety of sildenafil citrate (Viagra ® ) for the treatment of erectile dysfunction in men in Egypt and South Africa International Journal of Impotence Research (2003) 15, Suppl 1, S25–S29.Levinson et al Testosterone replacement therapy improves insulin resistance, glycaemic control, visceral adiposity and hypercholesterolaemia in hypogonadal men with Type II Diabetes Kapoor et al European Journal of Endocrinology 2006 Diabetes Chronic conplication Wiley press, Shaw et al The role of testosterone in erectile dysfunction Gooren et al