The function of sildenafil on female sexual pathways: a double-blind, cross-over, placebo-controlled study

Proceedings of PRINCETON IV: PDE5 inhibitors and cardiac health symposium

INTRODUCTION

Prior consensus meetings have addressed the relationship between phosphodiesterase type 5 (PDE5) inhibition and cardiac health. Given significant accumulation of new data in the past decade, a fourth consensus conference on this topic was convened in Pasadena, California, on March 10 and 11, 2023.

OBJECTIVES

Our meeting aimed to update existing knowledge, assess current guidelines, and make recommendations for future research and practice in this area.

METHODS

An expert panel reviewed existing research and clinical practice guidelines.

RESULTS

Key findings and clinical recommendations are the following: First, erectile dysfunction (ED) is a risk marker and enhancer for cardiovascular (CV) disease. For men with ED and intermediate levels of CV risk, coronary artery calcium (CAC) computed tomography should be considered in addition to previous management algorithms. Second, sexual activity is generally safe for men with ED, although stress testing should still be considered for men with reduced exercise tolerance or ischemia. Third, the safety of PDE5 inhibitor use with concomitant medications was reviewed in depth, particularly concomitant use with nitrates or alpha-blockers. With rare exceptions, PDE5 inhibitors can be safely used in men being treated for hypertension, lower urinary tract symptoms and other common male disorders. Fourth, for men unresponsive to oral therapy or with absolute contraindications for PDE5 inhibitor administration, multiple treatment options can be selected. These were reviewed in depth with clinical recommendations. Fifth, evidence from retrospective studies points strongly toward cardioprotective effects of chronic PDE5-inhibitor use in men. Decreased rates of adverse cardiac outcomes in men taking PDE-5 inhibitors has been consistently reported from multiple studies. Sixth, recommendations were made regarding over-the-counter access and potential risks of dietary supplement adulteration. Seventh, although limited data exist in women, PDE5 inhibitors are generally safe and are being tested for use in multiple new indications.

CONCLUSION

Studies support the overall cardiovascular safety of the PDE5 inhibitors. New indications and applications were reviewed in depth.

Overview of sexual dysfunction in patients with cancer

Among survivor's patients with cancer, sexual dysfunction (SD) is a common treatment-related disturbance that significantly affects their quality of life. The disorder can be a short-term effect, but frequently it can be permanent and patients often do not receive adequate support to overcome the problem. The characteristics of SD may differ depending on the type of neoplasm and oncological treatment. The most common long-term effects are those related to treatment-induced menopause, ablative oncologic surgery, and altered gonadal function. Breast, prostate, and gynecologic cancers are the tumors most commonly associated with disturbances in sexual health, although there is evidence of SD in patients with other types of neoplasms. It is necessary for the healthcare team caring for oncological patients to be aware of the characteristics of sexual dysfunction in this population. This will make it possible to offer patients a comprehensive and personalized approach to improve their quality of life.

Ultrastructural Study of Clitoral Cavernous Tissue and Clitoral Blood Flow From Type 1 Diabetic Premenopausal Women on Phosphodiesterase-5 Inhibitor

BACKGROUND

The effects of phosphodiesterase-type 5 (PDE5) inhibitors on the in vivo clitoral structure of women with diabetes have never been investigated.

AIM

To study the in vivo structural and hemodynamic changes of the clitoris in premenopausal women with type 1 diabetes on PDE5 inhibitors.

METHODS

38 premenopausal women with type 1 diabetes aged 36 -46 years. A randomized 1:1 study design was used: Study Group (group A) on Tadalafil 5 mg daily, and control group (group B). Blood samples were taken from each woman to measure HbA1c, testosterone, and Free Androgen Index. The women underwent microbiopsy of the clitoral body by means of semiautomatic gun during total anesthesia for surgery therapy of a benign gynecological pathology. The tissue removed was processed for electron microscopy. Translabial color Doppler ultrasound was used to measure the peak systolic velocity (PSV), the end diastolic velocity (EDV), and the pulsatility index (PI) of clitoral arteries.

MAIN OUTCOME MEASURES

Micro-ultrastructure observation of clitoral tissue and color Doppler sonography of clitoral blood flow.

RESULTS

Of the 38 women, 13 (68.4%) of group A and 15 (78.9%) of group B completed the study. Group A showed a mean PSV and EDV increase, and a mean PI decrease with respect to baseline (P < .001). Group B did not show any change in both the parameters (P = NS). By a quantitative study in both groups a variable degree of ultrastructural abnormalities of smooth muscle cells (SMCs) was observed, consisting in increased glycogen and lipoic deposits, cytoplasmic vacuoles, and focal increase of electron density of SMCs. Moreover, the mean SMC thickness of group A (1.83 ± 0.68 µm) was larger than that of group B (1.3 ± 0.41 µm) (P = .02).

CLINICAL IMPLICATIONS

PDE5 inhibitors could be used to treat diabetic women with genital arousal disorder.

STRENGTHS & LIMITATIONS

The study shows a clear effect of PDE5 inhibitors on clitoral SMCs. However, a limit was to not have investigated the sexual function/behavior of women of both groups, this was because of the short time of the study.

CONCLUSION

This study could help to understand in what way PDE5 inhibitors act on the ultrastructural pathophysiological clitoral cavernous tissue of women with diabetes. It could support PDE5 inhibitor usage in women with genital sexual arousal disorder due to metabolic diseases. Caruso S, Cianci A, Cianci S, et al. Ultrastructural Study of Clitoral Cavernous Tissue and Clitoral Blood Flow From Type 1 Diabetic Premenopausal Women on Phosphodiesterase-5 Inhibitor. J Sex Med 2019;16:375-382.

Sex Differences in the Treatment of Sexual Dysfunction

PURPOSE OF REVIEW

Sex differences in the treatment of sexual dysfunction are partly due to neurobiological differences, as well as, the central and peripheral physiological effects of hormones and neurotransmitter actions on reproductive systems in men and women. Differences in epidemiology of complaints and diagnostic considerations, variance in medical comorbidities, and interference from related medications also contribute to the need for different strategies for treatments of sexual dysfunction according to gender.

RECENT FINDINGS

Flibanserin and ospemifene are new medication treatment options that may help some women with symptoms of sexual dysfunction. Various therapies are available to address sexual dysfunction and sex differences are relevant to consider, in terms of diagnosis, effectiveness of treatments, and side effect profiles that may help determine indication, safety, and outcomes for specific treatments.

Randomized crossover study investigating daily versus on-demand vulvar Visnadine spray in women affected by female sexual arousal disorder

The aim of the study was to verify the efficacy of vulvar Visnadine spray in premenopausal women affected by female sexual arousal disorder (FSAD). Thirty-eight women aged 25-40 years affected by FSAD were enrolled in the randomized crossover study, by two possible sequences: on-demand, washout, daily (A sequence); and daily, washout, on-demand (B sequence). The Female Sexual Function Index (FSFI) and the Female Sexual Distress Scale (FSDS) were used to assess sexual function and sexual distress, respectively. Color Doppler ultrasonography was used to measure clitoral blood flow. The study had two follow-ups at 30 (T1) and 60 days (T2). Thirty-one women completed the study. Mean (SD) sexual activity and vulvar Visnadine spray usage was 1 ± 0.9 weekly during on-demand administration for both the sequences (Vs T0, p = NS). The mean sexual activity during daily usage was 2 ± 0.9 (Vs T0, p < .004) and 2 ± 0.8 (Vs T0, p < .001) for A and B sequences, respectively. FSFI total score, particularly genital arousal, improved more during the daily than during on-demand phases of both sequences (p < .001). Finally, clitoral blood flow improved significantly during daily usage of both the sequences (p < .001). Our study suggests that vulvar Visnadine spray could improve sexual performance of women affected by FSAD, producing changes in subjective and objective sexual aspects.

Female Sexual Dysfunction-Medical and Psychological Treatments, Committee 14

INTRODUCTION

Since the millennium we have witnessed significant strides in the science and treatment of female sexual dysfunction (FSD). This forward progress has included (i) the development of new theoretical models to describe healthy and dysfunctional sexual responses in women; (ii) alternative classification strategies of female sexual disorders; (iii) major advances in brain, hormonal, psychological, and interpersonal research focusing on etiologic factors and treatment approaches; (iv) strong and effective public advocacy for FSD; and (v) greater educational awareness of the impact of FSD on the woman and her partner.

AIMS

To review the literature and describe the best practices for assessing and treating women with hypoactive sexual desire disorder, female sexual arousal disorder, and female orgasmic disorders.

METHODS

The committee undertook a comprehensive review of the literature and discussion among themselves to determine the best assessment and treatment methods.

RESULTS

Using a biopsychosocial lens, the committee presents recommendations (with levels of evidence) for assessment and treatment of hypoactive sexual desire disorder, female sexual arousal disorder, and female orgasmic disorders.

CONCLUSION

The numerous significant strides in FSD that have occurred since the previous International Consultation of Sexual Medicine publications are reviewed in this article. Although evidence supports an integrated biopsychosocial approach to assessment and treatment of these disorders, the biological and psychological factors are artificially separated for review purposes. We recognize that best outcomes are achieved when all relevant factors are identified and addressed by the clinician and patient working together in concert (the sum is greater than the whole of its parts). Kingsberg SA, Althof S, Simon JA, et al. Female Sexual Dysfunction-Medical and Psychological Treatments, Committee 14. J Sex Med 2017;14:1463-1491.

Flibanserin for hypoactive sexual desire disorder: place in therapy

The pathophysiology, diagnosis and treatment of female sexual interest in pre- and post-menopausal women present a complex arena for patients and physicians to navigate. Flibanserin was the first pharmacologic treatment, approved by the United States Food and Drug Administration in August 2015, for hypoactive sexual desire disorder (HSDD) in premenopausal women. Side effects, contraindications and lack of approval in postmenopausal women are all limitations, as are issues surrounding patient and physician knowledge and access. Testosterone, buspirone, sildenafil, bupropion, bremelanotide, as well as herbal medications (Herbal vX or Tribulus terrestris) have demonstrated some clinical benefit in women with sexual dysfunction disorders however, trials have significant design, dosing or generalizability limitations. Nonpharmaceutical cognitive behavioral therapy, mindfulness meditation, pelvic floor therapy, and clitoral stimulators are also interventions women may pursue. This manuscript will explore the clinical data regarding these therapeutic modalities so as to bring attention to this issue of female HSDD, to offer an overview of current research, and to incite providers to initiate discussion among themselves and their patients.

Women's Sexual Health and Reproductive Function After SCI

Sexual function and to a lesser extent reproduction are often disrupted in women with spinal cord injuries (SCI), who must be educated to better understand their sexual and reproductive health. Women with SCI are sexually active; they can use psychogenic or reflexogenic stimulation to obtain sexual pleasure and orgasm. Treatment should consider a holistic approach using autonomic standards to describe remaining sexual function and to assess both genital function and psychosocial factors. Assessment of genital function should include thoracolumbar dermatomes, vulvar sensitivity (touch, pressure, vibration), and sacral reflexes. Self-exploration should include not only clitoral stimulation, but also stimulation of the vagina (G spot), cervix, and nipples conveyed by different innervation sources. Treatments may consider PDE5 inhibitors and flibanserin on an individual basis, and secondary consequences of SCI should address concerns with spasticity, pain, incontinence, and side effects of medications. Psychosocial issues must be addressed as possible contributors to sexual dysfunctions (eg, lower self-esteem, past sexual history, depression, dating habits). Pregnancy is possible for women with SCI; younger age at the time of injury and at the time of pregnancy being significant predictors of successful pregnancy, along with marital status, motor score, mobility, and occupational scores. Pregnancy may decrease the level of functioning (eg, self-care, ambulation, upper-extremity tasks), may involve complications (eg, decubitus ulcers, weight gain, urological complications), and must be monitored for postural hypotension and autonomic dysreflexia. Taking into consideration the physical and psychosocial determinants of sexuality and childbearing allows women with SCI to achieve positive sexual and reproductive health.

Comparing the effects of treatment with sildenafil and cognitive-behavioral therapy on treatment of sexual dysfunction in women: a randomized controlled clinical trial

Background

Sexual dysfunction in women is prevalent and common in women after menopause. Many attempts to treat patients with sexual dysfunction by cognitive-behavioral therapy (CBT) methods. But to the best of our knowledge, there has been no study that compared these two methods.

Objective

The aim of this study was to assess and compare the effects of sildenafil and cognitive-behavioral therapy on treatment of sexual dysfunction in women.

Methods

In this randomized, controlled, clinical trial, 86 women with arousal and orgasm dysfunction were surveyed. The patients were divided into two groups, i.e., sildenafil and CBT groups. The patients in the sildenafil group were treated by 50 mg of oral sildenafil one hour before intercourse, and the other group had weekly sessions of CBT for eight weeks. Sexual dysfunctions were evaluated by the Female Sexual Function Index (FSFI), a sexual satisfaction questionnaire, and the Enrich marital satisfaction scale.

Results

The mean age of the participants was 33.14 ± 7.34 years. The mean scores for female sexual function index, sexual satisfaction, and the Enrich marital satisfaction scale were increased in both groups during treatment (p < 0.001). It was found that cognitive-behavioral therapy compared to treatment with sildenafil increased all subscales, except arousal, orgasm, and lubrication.

Conclusion

Cognitive-behavioral therapy is more effective than treatment with sildenafil for improving female sexual function.

Clinical trial registration

The trial was registered at the Iranian Registry of Clinical Trials (http://www.irct.ir) with the IRCT ID: IRCT2014070318338N1.

Funding

The authors received no financial support for the research, authorship, and/or publication of this article.

Sexual dysfunction in patients with spinal cord lesions

Many aspects of sexuality can be disrupted following a spinal cord lesion (SCL). It can alter an individual's self-esteem and body image, interfere with positioning and mobility, introduce unexpected problems with incontinence and spasticity, decrease pleasure, and delay orgasm. Sexual concerns in men can involve erectile function, essential for intercourse, ejaculation function, necessary for fertility, and the ability to reach orgasm. In women they can involve concerns with vaginal lubrication, genital congestion, and vaginal infections, which can all go unnoticed, and orgasm, which may be lost. All of these concerns must be addressed during rehabilitation as individuals with SCL continue to live an active sexual life, and consider sexuality among their top priority for quality of life. This chapter describes the impact of SCL on various phases of men's and women's sexual responses and on various aspects of sexuality. Treatments are described in terms of what is currently available and what is specific to the SCL population. New approaches in particular for women are described, along with tips from sexual counseling which consider an overall approach, taking into account the primary, secondary, and tertiary consequences of the SCL on the individual's sexuality. Throughout the chapter, attempts are made to integrate neurophysiologic knowledge, findings from the literature on SCL, and clinical experience in sexual rehabilitation.

Efficacy of psychosocial interventions in men and women with sexual dysfunctions--a systematic review of controlled clinical trials: part 2--the efficacy of psychosocial interventions for female sexual dysfunction

INTRODUCTION

As yet, a summary of the research evidence concerning the efficacy of psychological treatment in female sexual dysfunction is lacking. Previous reviews were often nonsystematic or explored one specific sexual dysfunction.

AIM

Our systematic review provides an overview of the efficacy of psychosocial interventions in all female sexual dysfunction.

MAIN OUTCOME MEASURES

Main outcome measures included for example psychometrically validated scales, diary notes, interviews, and vulvar algesiometer. The efficacy of psychosocial interventions was measured for example by the frequency of and satisfaction with sexual activity and sexual functioning. Safety and acceptance were evaluated on the basis of adverse events and dropout rates.

METHODS

The systematic literature search included electronic database search, handsearch, contact with experts, and an ancestry approach. Studies were included if the woman was given a formal diagnosis of a sexual dysfunction (International Statistical Classification of Diseases and Related Health Problems-ICD10/-9; Diagnostic and Statistical Manual of Mental Disorders-IV/-III-R) and when the intervention was psychosocial or psychotherapeutic. The control group included either another treatment or a waiting-list control group. The report of relevant outcomes was necessary for inclusion as well as the design of the study (randomized, controlled trials [RCTs] and controlled clinical trials). The assessment of methodological quality comprised aspects of randomization, blinding, incomplete outcome data, selective reporting, and allegiance.

RESULTS

We identified 15 RCTs that investigated efficacy in female sexual dysfunction and two further studies that examined male and female sexual dysfunction together. Most trials explored sexual pain disorders. About half of all studies in women used either a concept derived from Masters and Johnson or a cognitive-behavioral treatment program. Both approaches showed significant improvements compared with a control group. Benefit was not always maintained over the (variable) follow-up period.

CONCLUSIONS

Traditional sexual therapeutic concepts proved to be efficacious in the treatment of female sexual dysfunction. A shortcoming was the rather low methodological quality of included studies.

Polymer-Based Nitric Oxide Therapies: Recent Insights for Biomedical Applications

Since the discovery of nitric oxide (NO) in the 1980s, this cellular messenger has been shown to participate in diverse biological processes such as cardiovascular homeostasis, immune response, wound healing, bone metabolism, and neurotransmission. Its beneficial effects have prompted increased research in the past two decades, with a focus on the development of materials that can locally release NO. However, significant limitations arise when applying these materials to biomedical applications. This Feature Article focuses on the development of NO-releasing and NO-generating polymeric materials (2006-2011) with emphasis on recent in vivo applications. Results are compared and discussed in terms of NO dose, release kinetics, and biological effects, in order to provide a foundation to design and evaluate new NO therapies.

Disorders in sexual desire and sexual arousal in women, a 2010 state of the art

In this contribution, female sexual desire and arousal disorders are viewed from the perspective of incentive motivation and information processing models of sexual response. The effects of hormones, somatic disease, and medication on sexual arousability are discussed, as well as the influence of psychological factors, such as stimulus meaning, mood and cognition, and relational context on female sexual desire and arousal. Specific topics to attend to during the anamnesis of sexual desire and arousal problems, and empirically evaluated psychological and pharmacological treatments for these problems are discussed.

Sildenafil citrate for female sexual arousal disorder: a future possibility?

Female sexual arousal disorder (FSAD) is a common disorder encountered in clinical practice, with self-reported arousal difficulties reported in up to 26% of American women. Various oral therapies for FSAD have been studied, including sildenafil citrate, a phosphodiesterase inhibitor that is currently used to treat male erectile dysfunction. In vitro studies of sildenafil citrate have demonstrated smooth-muscle relaxation in clitoral tissue, and phosphodiesterase type-5 has been shown to be present in vaginal, clitoral and labial smooth muscle; these findings have led to theories that sildenafil citrate might be successful for treating FSAD. This Review discusses the data from clinical trials that have assessed sildenafil citrate for the treatment of FSAD; the trials show that sildenafil citrate is moderately effective. Sildenafil citrate may also be effective in women with FSAD secondary to multiple sclerosis, diabetes or antidepressant use; however, more trials in these patient populations are required to confirm these findings.

Phosphodiesterase type 5 inhibitors and female sexual response: faulty protocols or paradigms?

INTRODUCTION

Phosphodiesterase type 5 inhibitors (PDE5), such as sildenafil, tadalafil, and vardenafil, have revolutionized the treatment of erectile dysfunction. Few successes, in contrast, have been reported for the use of these agents in treatment of sexual arousal problems in women.

AIM

To review research examining efficacy of PDE5 in women, critique the methods and models employed, and integrate the findings within a broader, gender-specific understanding of female sexual response.

METHODS

A conceptual and methodological review of all published studies examining PDE5 efficacy in female samples.

MAIN OUTCOME MEASURES

Study methods, populations, outcome measures, study results.

RESULTS

A total of 16 studies were reviewed. Studies using self-reported measures of sexual functioning showed mixed results whereas studies examining physiological effects of PDE5 on genital vasocongestion consistently report significant effects on genital sexual response.

CONCLUSIONS

The lack of efficacy of PDE5 treatment in women is likely attributable to gender differences in the concordance between physiological and psychological components of sexual response. Discordance between genital and subjective measures of sexual response in women may be augmented by PDE5 effects on genital vasocongestion in some populations, rendering successful treatment unlikely via pharmacological treatment alone.

A literature review and case reports series on the use of phosphodiesterase inhibitors in the treatment of female sexual dysfunction

Summary

The term ‘female sexual dysfunction’ (FSD) encompasses a number of different disorders, and while their aetiologies are not fully understood, the sub-classifications of this broad umbrella term are increasingly becoming more established and accepted. However, there is less consensus regarding the optimal treatment of these conditions. While it is known that phosphodiesterase (PDE5) is involved in the female sexual response, the clinical and research evidence supporting the unlicensed use of PDE5 inhibitors (PDE5i) in women is inconclusive and at times contradictory. In this article we explore this further by means of a comprehensive literature review on the use of PDE5i in the treatment of FSD and we also present our clinical experience of using these drugs in this context.

Oral phosphodiesterase type 5 inhibitors: nonerectogenic beneficial uses

INTRODUCTION

Phosphodiesterase type 5 (PDE5) hydrolyses cyclic guanylate monophosphate (cGMP) specifically to 5' GMP. PDE5 inhibitors were a breakthrough medication that addressed a previously unfulfilled medical need. They promoted vascular relaxation in the corpora cavernosa and penile erection during sexual stimulation. Sildenafil, vardenafil, and tadalafil were approved then introduced as effective treatments for male erectile dysfunction. This impact has stimulated academic, clinical, and industrial research.

AIM

To highlight the nonerectogenic beneficial uses of oral PDE5 inhibitors.

METHOD

A systematic review of published studies in this affair based on a Pubmed and medical subject heading databases search of all concerned articles.

MAIN OUTCOME MEASURES

Demonstrated beneficial as well as applicable uses of oral PDE5 inhibitors.

RESULTS

As chemical molecules, these drugs were shown to exert potential nonerectogenic beneficial effects. They showed efficacy as a useful adjunct in the management of pulmonary hypertension. Additional uses were extended to different utilities: essential hypertension, benign prostatic hyperplasia, gastrointestinal disorders, endothelial dysfunction, female sexual dysfunction, genital blood flow, exercise capacity, Raynaud's phenomenon, sperm motility, etc.

CONCLUSION

Exploring PDE5 inhibitors for their possible medical applications in diverse specialties seems to be beneficial in making use of these molecules for the welfare of humanity.

Blockade of phosphodiesterase Type 5 enhances rat neurohypophysial excitability and electrically evoked oxytocin release

Phosphodiesterase type 5 (PDE5) acts specifically on cyclic guanosine monophosphate (cGMP) and terminates cGMP-mediated signalling. PDE5 has a well established role in vascular smooth muscle, where specific inhibitors of PDE5 such as sildenafil correct erectile dysfunction by augmenting cGMP-mediated vascular relaxation. However, the role of PDE5 outside of the vasculature has received little attention. The present study tested PDE5 inhibitors on the cGMP-mediated modulation of K(+) channels in the neurohypophysis (posterior pituitary). Photolysis of caged-cGMP enhanced current through Ca(2+)-activated K(+) channels, and this enhancement recovered in about 2 min. Sildenafil essentially eliminated this recovery, suggesting that the reversal of K(+) current enhancement depends on cGMP breakdown. Activation of nitric oxide synthase during trains of activity in pituitary nerve terminals enhances excitability. When trains of stimulation were applied at regular intervals, sildenafil enhanced the excitability of neurohypophysial nerve terminals and increased the action potential firing probability. T-1032, a compound with high specificity for PDE5 over PDE6, had a similar action. Voltage imaging in intact neurohypophysis with a voltage sensitive absorbance dye showed that T-1032 reduced the failure of propagating action potentials during trains of activity. This indicates that PDE5 activity limits action potential propagation in neurohypophysial axons. Immunoassay of oxytocin, a neuropeptide hormone secreted by the posterior pituitary, demonstrated that sildenafil increased electrically evoked release. Thus, PDE5 plays an important role in the regulation of neurohypophysial function, and blockade of this enzyme can enhance the use-dependent facilitation of neurohypophysial secretion.

Current Management Strategies of the Postmenopausal Patient with Sexual Health Problems

INTRODUCTION

Sexual health concerns of menopausal women include decreases in sexual interest, arousal, lubrication, and orgasm, and increases in sexual pain, all of which may be associated with distress.

AIM

To review a step-care progression of sexual healthcare management: identification of the sexual health problem; education of the patient and the partner; modification of reversible causes; first-line therapies consisting of devices and medications; and second-line therapies with more invasive treatments including surgery.

METHODS

The healthcare provider is presented with a clinical diagnosis and treatment paradigm that engages mind, body, and relationship issues proceeding step-wise in a rational and cost-effective fashion.

MAIN OUTCOME MEASURE

Literature review in women's sexual health.

RESULTS

Women's health, including sexual health, is a fundamental human right. Supported by evidence-based data, a step-care approach to diagnosis and management of women with sexual health problems is advised. Multidisciplinary interventions should be considered as needed. Identification of sexual health concerns engages diagnostic components of psychologic consultation, history, physical examination, and laboratory testing as appropriate. Key to clinical assessment is the detailed sexual, medical, and psychosocial history. No agreement exists on necessary laboratory tests. Patient (and partner) education improves understanding of treatment options and expectations, and promotes a trusting patient-physician partnership. Modification of reversible causes includes sex therapy, lubricants, altering medications, modifying lifestyle and physical therapy for pelvic floor disorders. First-line therapies should be administered based upon diagnosis, needs, expectations, risks, benefits, and cost, and include medical devices and drugs such as hormones, vasoactive agents, dopamine agonists, topical steroids, anti-infectious agents, and analgesic agents. Second-line therapies, such as surgery, are initiated upon failure, insufficient response, or adverse side effects associated with one or more of the first-line therapies or patient preference.

CONCLUSIONS

For postmenopausal women with sexual dysfunction, a rational clinical management strategy begins with treatment options that are most reversible and least invasive and costly.

Pharmacological effects on sexual function

Many drugs may have effects on sexual function. Sexual function is complex and psychological and relationship issues are likely to have greater impacts on sexual function in women than drugs. Although it is important to understand the effects of drugs on sexual function, physicians should use caution in "medicalization" of sexual function in women [106].

Antidepressant‐Induced Inhibition of Genital Vascular Responses Is Reversed by Vardenafil in Female Rabbits

INTRODUCTION

Administration of serotonin reuptake inhibitors (SRI) or serotonin and norepinephrine reuptake inhibitors (SNRI) relieves depressive symptoms but may cause sexual dysfunction in women and men.

AIM

The aim of the present study was to evaluate the effects of the phosphodiesterase type 5 (PDE5) inhibitor, vardenafil, on inhibition of genital vascular responses (GVR) induced by SRI or SNRI administration in female rabbits.

METHODS

Vaginal and clitoral vasodilatory responses to pelvic nerve electrical stimulation were measured by laser Doppler flow needle probes.

RESULTS

GVR were significantly potentiated by vardenafil even at the low dose of 0.1 mg/kg, in clitoris and vagina (181 +/- 22% and 180 +/- 31% of control, in vagina and clitoris, respectively, at 8 Hz). The selective SRI, paroxetine (5 mg/kg), significantly inhibited GVR in female rabbits (54 +/- 5% and 48 +/- 6% of control). GVR were also significantly inhibited by the SNRIs, venlafaxine (5 mg/kg) (57 +/- 3% and 32 +/- 11%) and duloxetine (1 mg/kg) (40 +/- 7% and 28 +/- 5%). Treatment with vardenafil (0.1 and 0.3 mg/kg) completely reversed the inhibition of GVR induced by paroxetine, venlafaxine, or duloxetine.

CONCLUSIONS

Potentiation of the nitric oxide (NO) pathway by vardenafil improves vascular sexual responses in female rabbits and overcomes the inhibitory effects of acutely administered antidepressants on GVR, irrespective of the underlying pathophysiologic mechanism, i.e., disruption of the NO pathway or enhancement of alpha-adrenergic mechanisms. PDE5 inhibition may represent a reasonable approach to treat SRI- or SRNI-induced female sexual dysfunction, in particular, arousal disorders.

Pharmacology of erectile dysfunction in man

Erectile dysfunction (ED) is defined as the consistent or recurrent inability of a man to attain and/or maintain a penile erection sufficient for sexual activity (2nd International Consultation on Sexual Dysfunction-Paris, June 28th-July 1st, 2003). Following the discovery and introduction of sildenafil, research on the mechanisms underlying penile erection has had an enormous boost and many preclinical and clinical papers have been published in the last 5 years. This review is structured in order to give the reader an overview of the clinical and preclinical data available on the peripheral regulation of and the mediators involved in human penile erection. The most widely accepted risk factors for ED are discussed. The article is focused on human data, and the safety and effectiveness of the 3 commercially available Phosphodiesterase-5 (PDE5) inhibitors used to treat ED are also discussed.

Changes in clitoral blood flow in premenopausal women affected by type 1 diabetes after single 100-mg administration of sildenafil

OBJECTIVES

To verify whether sildenafil is effective in modifying clitoral blood flow in premenopausal women affected by type 1 diabetes.

METHODS

The setting was a diabetes outpatient clinic in which 30 premenopausal women affected by type 1 diabetes treated with insulin therapy and 39 healthy premenopausal women participated in our prospective open-label clinical study. Each diabetic woman received a single oral dose of 100 mg sildenafil. Translabial color Doppler ultrasonography was used to measure the resistance index, pulsatility index, peak systolic velocity, and end-diastolic velocity of the clitoral arteries 1 and 4 hours after sildenafil intake.

RESULTS

One hour after the administration of sildenafil, the mean resistance index was significantly lower and the mean pulsatility index, mean peak systolic velocity, and mean end-diastolic velocity of the clitoral arteries were significantly greater compared with baseline and 4 hours after sildenafil (P <0.05). The baseline clitoral blood flow of the diabetic women was lower compared with that of the control group (P <0.001).

CONCLUSIONS

Sildenafil seems to improve the clitoral blood flow of premenopausal women with type 1 diabetes.

Sildenafil improves sexual functioning in premenopausal women with type 1 diabetes who are affected by sexual arousal disorder: a double-blind, crossover, placebo-controlled pilot study

OBJECTIVE

To verify whether sildenafil is effective in type 1 premenopausal women affected by sexual arousal disorder (SAD).

DESIGN

Double-blind, crossover, placebo-controlled study.

SETTING

Gynecological diabetic outpatient clinic and sexual clinic.

PATIENT(S)

Thirty-six type 1 premenopausal diabetic women affected by SAD.

INTERVENTION(S)

Two 8-week periods of sildenafil 100 mg, washout, and placebo, by two possible sequences.

MAIN OUTCOMES MEASURE(S)

Each woman submitted blood samples to measure HbA(1c), and T, free T (FT), and PRL. Efficacy was assessed [1] subjectively by the Personal Experiences Questionnaire based on the 5-point Likert scale, quantifying arousal, desire, orgasm, enjoyment of sexual activities, and frequency of sexual relationships; and [2] objectively by translabial color Doppler ultrasound to measure the resistance index (RI), pulsatility index (PI), peak systolic velocity (PSV), and end diastolic velocity of clitoral arteries.

RESULT(S)

Thirty-two women completed the study. The mean HbA(1c) value was 8.0% +/- 1.8%, and plasma concentrations of T, FT, and PRL were normal. Sildenafil seems to improve arousal, orgasm and sexual enjoyment, and dyspareunia in women affected by type 1 diabetes. However, by flowmetric measurements, the mean RI was significantly lower and both the mean PI and PSV of the clitoral arteries were significantly higher compared with baseline and placebo.

CONCLUSION(S)

Sildenafil seems to improve subjective sexual aspects and can be used to treat objectively genital arousal disorder of premenopausal women with type 1 diabetes.

Physiology of female sexual function: animal models

INTRODUCTION

Data concerning the physiology of desire, arousal, and orgasm in women are limited because of ethical constraints. Aim. To gain knowledge of physiology of female sexual function through animal models.

METHODS

To provide state-of-the-art knowledge concerning female sexual function in animal models, representing the opinions of seven experts from five countries developed in a consensus process over a 2-year period.

MAIN OUTCOME MEASURE

Expert opinion was based on the grading of evidence-based medical literature, widespread internal committee discussion, public presentation, and debate.

RESULTS

Sexual desire may be considered as the presence of desire for, and fantasy about, sexual activity. Desire in animals can be inferred from certain appetitive behaviors that occur during copulation and from certain unconditioned copulatory measures. Proceptive behaviors are dependent in part on estrogen, progesterone, and drugs that bind to D1 dopamine receptors, adrenergic receptors, oxytocin receptors, opioid receptors, or gamma-amino butyric acid receptors. Peripheral arousal states are dependent on regulation of genital smooth muscle tone. Multiple neurotransmitters/mediators are involved including adrenergic, and nonadrenergic, noncholinergic agents such as vasoactive intestinal polypeptide, nitric oxide, neuropeptide Y, calcitonin gene-related peptide, and substance P. Sex steroid hormones, estrogens and androgens, are critical for structure and function of genital tissues including modulation of genital blood flow, lubrication, neurotransmitter function, smooth muscle contractility, mucification, and sex steroid receptor expression in genital tissues. Orgasm may be investigated by urethrogenital (UG) reflex, in which genital stimulation results in rhythmic contractions of striated perineal muscles and contractions of vagina, anus, and uterine smooth muscle. The UG reflex is generated by a multisegmental spinal pattern generator involving the coordination of sympathetic, parasympathetic, and somatic efferents innervating the genital organs. Serotonin and dopamine may modulate UG reflex activity.

CONCLUSIONS

More research is needed in animal models in the physiology of female sexual function.

Outcome measurement in female sexual dysfunction clinical trials: review and recommendations

Defining and measuring Female Sexual Dysfunction (FSD) is a complex and challenging task. Several factors have confounded the theory and measurement of FSD including: the use of an inappropriate male paradigm; difficulty in capturing the complexity of women's sexual response; an evolving but presently untested nosology; and the relative independence between subjective and objective aspects of women's sexual response. Each of these factors have contributed to the difficulty in developing meaningful and valid endpoints for clinical trials. The Food and Drug Administration's (FDA) 2000 draft guidance document for female sexual dysfunction clinical trials recommended the use of daily diary measures as primary and self-administered questionnaires (SAQs) as secondary endpoints. Event logs or diary measures may be adequate for assessing aspects of male sexual performance (e.g., erectile function), or in other therapeutic areas with discrete and readily observable endpoints (e.g., incontinence). However, psychometric theory suggests that for female sexual dysfunction clinical trials, SAQ instruments may provide more sensitive and reliable measures of outcome. We offer an alternative set of recommendations in the hope that the FDA will reconsider its position and to serve as potential guidelines for non-industry sponsored research on female sexuality as well. First, we propose that SAQs be elevated from their current status as secondary endpoints to be considered as potential primary endpoints in clinical trials of FSD. Second, we recommend that depending on the trial design and intervention under study, either an SAQ or diary measure (typically one or the other, and not both), might serve as a primary endpoint in a clinical trial. Third, SAQs and diaries should be employed, analyzed and interpreted in their particular areas of strength. Diaries are most useful for enumerating events and/or counting frequencies. SAQs are superior at gathering subjective data related to women's sexual function. Fourth, we believe there is a theoretical basis for considering SAQs to be superior measurement tools compared to diaries in assessing sexual dysfunction in women. At present, however there is insufficient objective data to fully support this opinion. Conversely, we do not anticipate either theoretical or objective evidence to support the alternative hypothesis (that diaries are superior to SAQs). If this proves to be correct in the future, diary measures may no longer be considered as primary endpoints for FSD clinical trials. Finally, we recommend that the FDA and/or other regulatory agencies reconsider the emphasis given to the number of successful or satisfactory sexual events over time as primary endpoints because they do not definitively demonstrate whether there has or has not been any improvement in the FSD endpoint under study (e.g., sexual desire). Successful and satisfactory encounters represent an amalgam of subjective assessments that are too far removed from the essential FSD component.

The metabolic syndrome: a cause of sexual dysfunction in women

Female sexual dysfunction (FSD) is a significant public health problem. We assessed the prevalence of FSD in premenopausal women with the metabolic syndrome as compared to the general female population. Compared with the control group (N = 80), women with the metabolic syndrome (N = 120) had reduced mean full Female Sexual Function Index (FSFI) score (23.2+/-5.4 vs 30.1+/-4.7, P < 0.001), reduced satisfaction rate (3.5+/-1.1 vs 4.7+/-1.2, P < 0.01), and higher circulating levels of C-reactive protein (CRP: 2.2 (0.6/4.9) vs 0.8 (0.2/2.9) mg/l, median (interquartile range), P = 0.01). There was an inverse relation between CRP levels and FSFI score (r = -0.32, P=0.02). Investigation of female sexuality is suggested for patients with the metabolic syndrome.