AUA 2005 - Take Home Message - Sexual Function / Dysfunction

The ISSM thanks very much Dr Raymond Costabile for having entrusted it to post this Take Home message on its website, as well as to publish it in its Newsbulletin. J Buvat MD, ISSM webmaster

Raymond A Costabile MD
Urology Department
University of Virginia Health System
Charlottesville, VA

This year�s AUA annual meeting extends the focus from previous years on the topics of pharmacological treatment of sexual function and sexual rehabilitation after prostate surgery. New agents to treat a variety of abnormalities of sexual function including premature ejaculation and female sexual dysfunction as well as continued evaluation of the safety and efficacy of FDA approved agents to treat erectile dysfunction are well represented by a series of excellent abstracts.

Sexual function following prostatectomy

Freedland et al showed that the recovery of sexual function after radical prostatectomy (RP) occurred at 24 months in 51% of men undergoing bilateral nerve sparing procedures vs. 32% of men undergoing unilateral nerve sparing. Zanni et al demonstrated that recovery of erectile function after RP correlated significantly with the rate of post-op sexual desire, mood deflection and incontinence. In looking at the concept of penile rehabilitation following RP, Raina et al showed early intraurethral MUSE therapy increased the incidence of sexual activity and erections after RP. Allaf, in an animal model of cavernous nerve injury, gave recombinant erythropoeiten or darbepoetin to promote axonal regeneration to improve recovery of sexual function. Studies of penile function after RP by Bannowsky, show that some men demonstrate adequate penile rigidity measured by NPT testing shortly after catheter removal. Lee discussed the phenomenon of �climacturia� or leakage of urine on orgasm which occurs in 45% of men following RP.

Pharmacological treatment of Erectile Dysfunction

An ongoing evaluation of approved PDE-5 inhibitors has better delineated the efficacy and side effect profile of these agents. Raina et al concluded that at five years following RP, 50% of initial sildenafil responders continue to show efficacy but only in men having bilateral nerve sparing procedures. Concomitant use of alpha blockers and vardenafil were shown to have a favorable safety profile in a �real world� post marketing surveillance trial. Similar results were seen by Hellstrom in an analysis of 17 placebo controlled trials using vardenafil. Hellstrom also reported on significantly reduced ejaculatory function in healthy volunteers taking tamsulosin. Further research is needed to better delineate the mechanism of this ejaculatory disturbance. Two papers looked at the real world implications of patients having prescriptions for nitrates and PDE-5 inhibitors despite the FDA mandated contraindication regarding concomitant use. Scales et al showed that two thirds of patients with overlapping prescriptions for medications with Level one interactions received prescriptions for nitrates and sildenafil. In a similar study, Shelton et al showed that 60% of patients prescribed nitrates on an �as needed� schedule had zero use of nitrates indicating that a significant number of patients prescribed a nitrate may be able to discard them and be candidates for PDE-5 therapy.

Pharmacological treatment of premature ejaculation (PE)

Researchers have suggested that PE may be the most common sexual dysfunction in men. An FDA approved therapy for the treatment of PE is presently not available. Several presentations looked at the mechanism, safety and efficacy of dapoxetine for the treatment of PE. Gengo et al studied the mechanism of competitive binding of dapoxetine to specific 3H citalopram binding sites on the 5-HT reuptake transporter to inhibit 5-HT, NE and DA. In pharmacological trials and concomitant use trials dapoxetine and ethanol co administered to healthy men did not produce significant changes in dapoxetine pharmacokinetic profiles and had no clinically significant adverse events in healthy subjects. No interaction was seen with use of PDE-5 inhibitors and dapoxetine as well. In dose ranging trials, Hellstrom and Pryor demonstrated significant efficacy (measured by intravaginal ejaculatory latency time � IELT) and safety for dapoxetine doses of 30mg and 60mg. Other drugs and drug combinations, including the combination of tadalafil and fluoxetine showed improved IELT over monotherapy with either agent or placebo. In order to accurately diagnose and evaluate treatment effect, Rosen et al studied predictions of the clinical diagnosis of PE and showed that IELT alone was not as accurate as the addition of patient reported outcomes (PRO). Patrick et al looked at other questions of patient satisfaction with ejaculatory function and showed significant differences in single item questions for patients with PE over those without PE.

Sexual function and men�s health

Several presentations focused on sexual dysfunction as an indication of over all men�s health. Shabsigh et al outlined the increased incidence of metabolic syndrome (central obesity, insulin dysregulation, abnormal lipids and hypertension) in men with erectile dysfunction. Conversely, Demir showed that metabolic syndrome was a potential risk factor for ED. Montorsi et al showed that ED pre-dated the development of symptomatic coronary artery disease in 71% of men evaluated for angina by 25 months. Indeed Sommer has concluded that PDE-5 inhibitors may ultimately be used to treat not only ED but prostate symptoms and cardiovascular disease.

Penile prosthetic surgery

While pharmacological therapy for sexual function remains a hot topic, significant advances continue to be made in surgical therapy for the treatment of male sexual dysfunction. Wilson et al discussed using rear tip extenders to repair proximal corporal perforations during implant surgery. Several authors presented data on the decreasing incidence of post-op implant infections using the antibiotic coated AMS Inhibizone� prosthesis. Fogla et al demonstrated low infection rates of 1.07% in patients undergoing prosthesis revision, significantly lower than previous studies. Other surgical improvements including the AMS two-piece inflatable Ambicor� prosthesis and the new AMS tactile pump were discussed.

Hypogonadism and the association between LUTS and ED

Kshirsagar et al presented information on a non-linear method of neural computation which uses age, ED and depression to accurately predict hypogonadism. In keeping with that topic, Gades used the ADAM questionnaire to predict androgen levels. Additional data showing an association between LUTS and ED was presented by Rosen. Interestingly a similar relationship was shown by Johnson et al linking sexual health in women with stress and urge incontinence.

Excitement in the field of sexual health continues to grow as we expand the diagnostic methods and treatment schemes to encompass a growing array of sexual problems.