The Journal of Sexual Medicine

Accurate estimates of prevalence/incidence are important in understanding the true burden of male and female sexual dysfunction and in identifying risk factors for prevention efforts. This is the summary of the report by the International Consultation Committee for Sexual Medicine on Definitions/Epidemiology/Risk Factors for Sexual Dysfunction.

The main aim of this article is to provide a general overview of the definitions of sexual dysfunction for men and women, the incidence and prevalence rates, and a description of the risk factors identified in large population-based studies.

Literature regarding definitions, descriptive and analytical epidemiology of sexual dysfunction in men and women were selected using evidence-based criteria. For descriptive epidemiological studies, a Prins score of 10 or higher was utilized to identify population-based studies with adequately stringent criteria. This report represents the opinions of eight experts from five countries developed in a consensus process and encompassing a detailed literature review over a 2-year period.

The study aims to provide state-of-the-art prevalence and incidence rates reported for each dysfunction and stratified by age and gender. Expert opinion was based on the grading of evidence-based medical literature, widespread internal committee discussion, public presentation, and debate.

A wealth of information is presented on erectile dysfunction, its development through time, and its correlates. The field is still in need of more epidemiological studies on the other men’s sexual dysfunction and on all women’s sexual dysfunctions.

A review of the currently available evidence from epidemiological studies is provided.

Sexual desire is controlled by brain systems involved in sexual excitation and inhibition. Hypoactive sexual desire disorder (HSDD) may result from hypofunctional excitation, hyperfunctional inhibition, or some mix of the two.

This study aimed to identify neurochemical and neuroanatomical systems involved in sexual excitation and inhibition, their role during normal, and hypoactive sexual expressions.

A comprehensive review of the human and animal literature is made, and a theory surrounding the ways that HSDD can be manifested and treated is presented.

Drug effects and neural systems derived largely from rat studies that are involved in the stimulation of sexual desire (excitatory system) vs. the stimulation of sexual reward, sedation, and satiety (inhibitory system).

Brain dopamine systems (incertohypothalamic and mesolimbic) that link the hypothalamus and limbic system appear to form the core of the excitatory system. This system also includes melanocortins, oxytocin, and norepinephrine. Brain opioid, endocannabinoid, and serotonin systems are activated during periods of sexual inhibition, and blunt the ability of excitatory systems to be activated.

Drugs that stimulate the activation of hypothalamic dopamine or that blunt endocannabinoid or serotonin release and/or postsynaptic binding may be effective in stimulating sexual desire in animals and humans. The characterization of how those drugs work will help generate a rational approach to drug development in the treatment of HSDD.

The medical literature contains several definitions of premature ejaculation (PE). The most commonly quoted definition, the American Psychiatric Association's Diagnostic and Statistical Manual of Mental Disorders-Fourth Edition-Text Revision, and other definitions of PE are all authority based rather than evidence based, and have no support from controlled clinical and/or epidemiological studies.

The aim of this article is to develop a contemporary, evidence-based definition of PE.

In August 2007, the International Society for Sexual Medicine (ISSM) appointed several international experts in PE to an Ad Hoc Committee for the Definition of Premature Ejaculation. The committee met in Amsterdam in October 2007 to evaluate the strengths and weaknesses of current definitions of PE, to critique the evidence in support of the constructs of ejaculatory latency, ejaculatory control, sexual satisfaction, and personal/interpersonal distress, and to propose a new evidence-based definition of PE.

The committee unanimously agreed that the constructs that are necessary to define PE are rapidity of ejaculation, perceived self-efficacy and control, and negative personal consequences from PE. The committee proposed that lifelong PE be defined as “. . . a male sexual dysfunction characterized by ejaculation which always or nearly always occurs prior to or within about one minute of vaginal penetration, and the inability to delay ejaculation on all or nearly all vaginal penetrations, and negative personal consequences, such as distress, bother, frustration and/or the avoidance of sexual intimacy.” This definition is limited to men with lifelong PE who engage in vaginal intercourse. The panel concluded that there are insufficient published objective data to propose an evidence-based definition of acquired PE.

The ISSM definition of lifelong PE represents the first evidence-based definition of PE. This definition will hopefully lead to the development of new tools and Patient Reported Outcome measures for diagnosing and assessing the efficacy of treatment interventions and encourage ongoing research into the true prevalence of this disorder and the efficacy of new pharmacological and psychological treatments.

Limited information is available concerning the general and sexual health status of European men.

To investigate the age-related changes in general and sexual health in middle-aged and older men from different countries of the European Union.

This is a cross-sectional multicenter survey performed on a sample of 3,369 community-dwelling men aged 40–79 years old (mean 60 ± 11 years). Subjects were randomly selected from eight European centers including centers from nontransitional (Florence [Italy], Leuven [Belgium], Malmö[Sweden], Manchester [United Kingdom], Santiago de Compostela [Spain]) and transitional countries (Lodz [Poland], Szeged [Hungary], Tartu [Estonia]).

Different parameters were evaluated including the Beck’s Depression Inventory for the quantification of depressive symptoms, the Short Form-36 Health Survey for the assessment of the quality of life (QoL), the International Prostate Symptom Score for the evaluation of lower urinary tract symptoms, and the European Male Ageing Study sexual function questionnaire for the study of sexual function.

More than 50% of subjects reported the presence of one or more common morbidities. Overall, hypertension (29%), obesity (24%), and heart diseases (16%) were the most prevalent conditions. Around 30% of men reported erectile dysfunction (ED) and 6% reported severe orgasmic impairment, both of which were closely associated with age and concomitant morbidities. Only 38% of men reporting ED were concerned about it. Furthermore, concern about ED increased with age, peaking in the 50–59 years age band, but decreased thereafter. Men in transitional countries reported a higher prevalence of morbidities and impairment of sexual function as well as a lower QoL.

Sexual health declined while concomitant morbidities increased in European men as a function of age. The burden of general and sexual health is higher in transitional countries, emphasizing the need to develop more effective strategies to promote healthy aging for men in these countries.

Premature ejaculation (PE) is the most common male sexual dysfunction affecting men and their partners. Lack of community-based data describing this condition limits understanding of PE and its outcomes.

To characterize PE in a large population of men with and without PE using patient-reported outcome (PRO) measures elicited from men and their partners.

4-week, multicenter, observational study of males (≥18 years) and their female partners in monogamous relationships (≥6 months). Screening, baseline, and follow-up visits scheduled at 2-week intervals. Clinicians diagnosed PE utilizing DSM-IV-TR criteria. Intravaginal ejaculatory latency time (IELT), measured by a stopwatch held by the partner, was recorded for each sexual intercourse experience. Subject and partner independently assessed PROs: control over ejaculationand satisfaction with sexual intercourse(0 = very poor to 4 = very good), personal distressand interpersonal difficulty(0 = not at all to 4 = extremely), and severity of PE(0 = none to 3 = severe).

Of the total study population (N = 1,587), 207 subjects were diagnosed with PE and 1,380 were assigned to the non-PE group. Median IELT (min) was 1.8 (range, 0–41) for PE and 7.3 (range, 0–53) for non-PE subjects (P < 0.0001). More PE vs. non-PE subjects gave ratings of “very poor” or “poor” for control over ejaculation(72% vs. 5%; P < 0.0001) and satisfaction with sexual intercourse(31% vs. 1%; P < 0.0001). More subjects in the PE vs. non-PE group gave ratings of “quite a bit” or “extremely” for personal distress(64% vs. 4%; P < 0.0001) and interpersonal difficulty(31% vs. 1%; P < 0.0001). Subject and partner assessments showed similar patterns and correlated moderately (0.36–0.57).

PE subjects reported significantly shorter IELT. Overlap in IELT distributions was observed between the PE and non-PE groups, indicating the need for additional PRO measures to characterize PE. Shorter IELT was significantly associated with reduced ejaculatory control and sexual satisfaction and increased distress and interpersonal difficulty.

No previous population-based studies have used validated instruments to measure female sexual dysfunction (FSD) in Australian women across a broad age range.

To estimate prevalence and explore factors associated with the components of FSD.

Sexual Function Questionnaire measured low sexual function. Female Sexual Distress Scale measured sexual distress.

Multivariate analysis of postal survey data from a random sample of 356 women aged 20–70 years.

Low desire was more likely to occur in women in relationships for 20–29 years (odds ratio 3.7, 95% confidence intervals 1.1–12.8) and less likely in women reporting greater satisfaction with their partner as a lover (0.3, 0.1–0.9) or who placed greater importance on sex (0.1, 0.03–0.3). Low genital arousal was more likely among women who were perimenopausal (4.4, 1.2–15.7), postmenopausal (5.3, 1.6–17.7), or depressed (2.5, 1.1–5.3), and was less likely in women taking hormone therapy (0.2, 0.04–0.7), more educated (0.5, 0.3–0.96), in their 30s (0.2, 0.1–0.7) or 40s (0.2, 0.1–0.7), or placed greater importance on sex (0.2, 0.05–0.5). Low orgasmic function was less likely in women who were in their 30s (0.3, 0.1–0.8) or who placed greater importance on sex (0.3, 0.1–0.7). Sexual distress was positively associated with depression (3.1, 1.2–7.8) and was inversely associated with better communication of sexual needs (0.2, 0.05–0.5). Results were adjusted for other covariates including age, psychological, socioeconomic, physiological, and relationship factors.

Relationship factors were more important to low desire than age or menopause, whereas physiological and psychological factors were more important to low genital arousal and low orgasmic function than relationship factors. Sexual distress was associated with both psychological and relationship factors.

5α-reductase inhibitors (5α-RIs), finasteride and dutasteride, have been approved for treatment of lower urinary tract symptoms, due to benign prostatic hyperplasia, with marked clinical efficacy. Finasteride is also approved for treatment of hair loss (androgenetic alopecia). Although the adverse side effects of these agents are thought to be minimal, the magnitude of adverse effects on sexual function, gynecomastia, depression, and quality of life remains ill-defined.

The goal of this review is to discuss 5α-RIs therapy, the potential persistent side effects, and the possible mechanisms responsible for these undesirable effects.

We examined data reported in various clinical studies from the available literature concerning the side effects of finasteride and dutasteride.

Data reported in the literature were reviewed and discussed.

Prolonged adverse effects on sexual function such as erectile dysfunction and diminished libido are reported by a subset of men, raising the possibility of a causal relationship.

We suggest discussion with patients on the potential sexual side effects of 5α-RIs before commencing therapy. Alternative therapies may be considered in the discussion, especially when treating androgenetic alopecia.

Low-energy shockwave therapy (LESWT) has been shown to improve erectile function in patients suffering from diabetes mellitus (DM)-associated erectile dysfunction (ED). However, the underlying mechanism remains unknown.

The aim of this study is to investigate whether LESWT can ameliorate DM-associated ED in a rat model and examine the associated changes in the erectile tissues.

Newborn male rats were intraperitoneally injected with 5-ethynyl-2-deoxyuridine (EdU; 50 mg/kg) for the purpose of tracking endogenous mesenchymal stem cells (MSCs). Eight weeks later, eight of these rats were randomly chosen to serve as normal control (N group). The remaining rats were injected intraperitoneally with 60 mg/kg of streptozotocin (STZ) to induce DM. Eight of these rats were randomly chosen to serve as DM control (DM group), whereas another eight rats were subject to shockwave (SW) treatment (DM+SW group). Each rat in the DM+SW group received 300 shocks at energy level of 0.1 mJ/mm2 and frequency of 120/minute. This procedure was repeated three times a week for 2 weeks. Another 2 weeks later, all 24 rats were evaluated for erectile function by intracavernous pressure (ICP) measurement. Afterward, their penile tissues were examined by histology.

Erectile function was measured by ICP. Neuronal nitric oxide synthase (nNOS)-positive nerves and the endothelium were examined by immunofluorescence staining. Smooth muscle and MSCs were examined by phalloidin and EdU staining, respectively.

STZ treatment caused a significant decrease in erectile function and in the number of nNOS-positive nerves and in endothelial and smooth muscle contents. These DM-associated deficits were all partially but significantly reversed by LESWT. MSCs (EdU-positive cells) were significantly more numerous in DM+SW than in DM rats.

LESWT can partially ameliorate DM-associated ED by promoting regeneration of nNOS-positive nerves, endothelium, and smooth muscle in the penis. These beneficial effects appear to be mediated by recruitment of endogenous MSCs.

Premature ejaculation (PE) has been associated with a range of negative psychological effects, including anxiety, depression, and distress in men and their female partners.

To review evidence of the psychosocial concomitants of premature ejaculation in recent observational studies, and to consider the psychosocial and quality of life outcomes associated with PE, including effects on the partner relationship.

Psychosocial and quality of life consequences related to premature ejaculation.

A literature search was performed to retrieve publications relating to management or treatment of PE or male sexual dysfunction. Publications were included if they reported the impact of PE on the man, his partner or relationship, or the impact of male sexual dysfunction and included PE in the analysis.

Eleven observational studies were selected. All these studies found evidence for an association between PE and adverse psychosocial and quality of life consequences, including detrimental effects on the partner relationship. Comparative analyses were restricted by major differences across the studies.

PE significantly negatively impacts men and their partners and may prevent single men forming new partner relationships. Men are reluctant to seek treatment from their physicians, although they may be more encouraged to do so through their partner's support and the availability of effective treatments. There is a need for validated diagnostic screening criteria and validated, reliable, brief patient-reported outcome measures that can be used to assess men with PE and their partners. These factors would allow further studies with more complete and accurate assessment of the impact of PE.

Low-intensity shock wave therapy (LI-ESWT) has been reported as an effective treatment in men with mild and moderate erectile dysfunction (ED).

The aim of this study is to determine the efficacy of LI-ESWT in severe ED patients who were poor responders to phosphodiesterase type 5 inhibitor (PDE5i) therapy.

This was an open-label single-arm prospective study on ED patients with an erection hardness score (EHS) ≤ 2 at baseline. The protocol comprised two treatment sessions per week for 3 weeks, which were repeated after a 3-week no-treatment interval. Patients were followed at 1 month (FU1), and only then an active PDE5i medication was provided for an additional month until final follow-up visit (FU2).

At each treatment session, LI-ESWT was applied on the penile shaft and crus at five different anatomical sites (300 shocks, 0.09 mJ/mm2 intensity at120 shocks/min).

Each subject underwent a full baseline assessment of erectile function using validated questionnaires and objective penile hemodynamic testing before and after LI-ESWT.

Outcome measures used are changes in the International Index of Erectile Function-erectile function domain (IIEF-ED) scores, the EHS measurement, and the three parameters of penile hemodynamics and endothelial function.

Twenty-nine men (mean age of 61.3) completed the study. Their mean IIEF-ED scores increased from 8.8 ± 1 (baseline) to 12.3 ± 1 at FU1 (P = 0.035). At FU2 (on active PDE5i treatment), their IIEF-ED further increased to 18.8 ± 1 (P < 0.0001), and 72.4% (P < 0.0001) reached an EHS of ≥3 (allowing full sexual intercourse). A significant improvement (P = 0.0001) in penile hemodynamics was detected after treatment and this improvement significantly correlated with increases in the IIEF-ED (P < 0.05). No noteworthy adverse events were reported.

Penile LI-ESWT is a new modality that has the potential to treat a subgroup of severe ED patients. These preliminary data need to be reconfirmed by multicenter sham control studies in a larger group of ED patients.