Review study confirms gender difference in responses to sexual stimuli.

Women’s minds and genitals respond differently to sexual arousal, whereas in men, the responses of the body and mind are more in tune with each other, according to Assistant Professor Meredith Chivers, from Queen’s University in Kingston, Canada, and her international collaborators, Michael Seto, Martin Lalumière, Ellen Laan, and Teresa Grimbos. Their meta-analysis1 of the extent of agreement between subjective ratings and physiological measures of sexual arousal in men and women is published online this week in Springer’s journal Archives of Sexual Behavior.

The human sexual response is a dynamic combination of cognitive, emotional and physiological processes. Chivers and colleagues were interested in the degree to which an individual’s experience of sexual arousal mirrors physiological genital activity and whether gender difference in this agreement (commonly reported in individual studies) would be found when a meta-analysis of sexual psychophysiology studies was conducted.

The authors reviewed 134 studies, published between 1969 and 2007, which measured the degree of agreement between subjective experiences of sexual arousal and physiological genital responses. Overall, the studies reviewed data collected from over 2,500 women and 1,900 men. Participants indicated how aroused they felt during or after they were exposed to a variety of sexual stimuli, called subjective arousal. Researchers measured the physiological responses to the sexual stimuli using different methods, including changes in penile erection for men and changes in genital blood flow for women.

Men’s subjective and physiological measures of sexual arousal showed a greater degree of agreement than women’s. For the male participants, the subjective ratings more closely matched the physiological readings indicating that men’s minds and genitals were in agreement. For the women, however, the responses of the mind and genitals were not as closely matched as men’s, suggesting a split between women’s bodies and minds. The readings from the physiological measurements and their subjective ratings were, in some cases, significantly different.

The researchers then looked at factors in the studies that might shed some light on this gender difference. They identified two methodological differences, in particular, that may play a role.

The type of sexual stimuli – their content and how it was presented e.g. visually or as an audio recording – made no difference to how well the subjective and physiological responses mirrored each other in men. However, it did influence women’s responses. Women exposed to a greater range and number of sexual stimuli – content and presentation – were more likely to have stronger agreement between subjective and physiological responses.

The timing of the assessment of self-reported sexual arousal also had an effect. When participants were asked to rate their subjective arousal at the end of each stimulus, men’s responses were closer to one another than women’s. However, when both men and women were asked to rate their arousal whilst they were exposed to the stimulus, the gender difference disappeared because men’s concordance dropped to the range of women’s.

The authors conclude: “The assessment of sexual arousal in men and women informs theoretical studies of human sexuality and provides a method to assess and evaluate the treatment of sexual dysfunctions. Understanding measures of arousal is, therefore, paramount to further theoretical and practical advances in the study of human sexuality. Our results have implications for the assessment of sexual arousal, the nature of gender differences in sexual arousal, and models of sexual response.”

A new study shows that older men with restless leg syndrome (RLS) also suffer from higher rates of erectile dysfunction. The findings also show that increased frequency of restless leg syndrome leads to worsening erectile dysfunction for men.

For men who have restless leg syndrome 15 times a month or more, the incidence of erectile dysfunction was as high as seventy eight percent, and lower for those who experienced fewer episodes of RLS monthly.

The study, published in the journal Sleep suggests that restless leg syndrome and erectile dysfunction share the same mechanism.

For older men without restless leg syndrome the occurrence of erectile dysfunction was forty percent. For older men who reported restless leg syndrome, erectile dysfunction incidence was fifty three percent. The study came from an analysis of 23,119 men who participated in the Health Professional Follow-up Study. Information about erectile dysfunction and RLS was obtained via questionnaire. Average age of the men was 69, that included male dentists, optometrists, osteopaths, podiatrists, pharmacists and veterinarians in the US. Approximately four percent of the men had RLS.

According to lead author Xiang Gao, MD, PhD, instructor at Harvard Medical School, associate epidemiologist at Brigham and Women’s Hospital and research scientist at the Harvard School of public health in Boston, Mass, “The mechanisms underlying the association between RLS and erectile dysfunction could be caused by hypofunctioning of dopamine in the central nervous system, which is associated with both conditions.”

Scientists do not know what causes restless leg syndrome, a condition that is more prevalent in middle aged women and older adults. RLS causes frequent movement of the legs and uncomfortable sensations that interfere with sleep because of a persistent uncontrollable urge to move the legs. There are several identified factors that make restless leg syndrome worse, including stress, Parkinson’s disease, kidney disease, pregnancy, iron deficiency, and certain medications. Heredity might play a role, but the source of the condition has not yet been discovered.

The findings from the current study suggest that sleep apnea could play a role in both restless leg syndrome and erectile dysfunction through decreased levels of circulating testosterone.

The study is not conclusive in that it does not establish cause. The scientists say further studies are needed to uncover the biological mechanisms linking restless leg syndrome to erectile dysfunction in older men. For men who experience restless leg syndrome in addition to erectile dysfunction, a sleep study could be of benefit, and may be worth discussing with your physician.

Modern, couple-oriented treatment for male sexual dysfunction takes the psychosocial aspects of sex into account, as well as focussing on the purely physical aspects of the problem. The importance of this biopsychosocial approach, whether one looks at disorders of desire, arousal or orgasm, is supported by intercultural comparisons, among other data. But sexual dysfunction can also arise as a consequence of a variety of diseases and their treatments, such as depression or diabetes, or can even be an early warning sign of serious physical illness such as heart disease. Hence an interdisciplinary approach, drawing on both medical and psychological techniques and insights, is essential.
The authors use research on prostate cancer to underline the place of one important new development in German sex therapy, a form of the internationally familiar “couples” therapy called “syndiastic” therapy. Questionnaire surveys to men with prostate cancer show that while the importance of the genital aspects of sexuality decreased in importance following radical surgery, the relationship and physical intimacy remained as important as before. “Syndiastic” sex therapy was introduced in Germany in 2004, and focussed for the first time explicitly on fundamental psychosocial needs, in a wider way, rather than purely on sexual function itself. Derived from a word Aristotle uses, meaning a disposition to “live in pairs” or “belonging,” this approach differs importantly from some other somatic or psychological treatments which focus mainly on restoring sexual function. Instead, it aims to broaden the understanding of sexuality, extend the range of physical experience, and improve overall satisfaction within the relationship.

UroToday.com – Erectile dysfunction is the most commonly recognized side effect of radical prostatectomy (RP) for prostate cancer (CaP). However, post-surgery penile length shortening (PLS) is known to occur in up to three-fourths of men. The impact of PLS has not previously been assessed.

The mechanism causing PLS is not known, but may be related to anatomic changes or fibrosis and scaring in the retropubic space. Studies suggest that men are more concerned with penile length than women, and that men desiring penile lengthening actually have normal penile length. The goal of this study that appears in the European Journal of Oncology Nursing was to determine patients’ perceptions and responses to PLS after RP.

Six participants were recruited by open invitation from a CaP support group. The main criterion for inclusion was perception of PLS at least one year after undergoing RP. Five of the six men were married. Most were of Caucasian descent and had completed secondary education. None of the men reported to be able to achieve adequate erections for penetrative sex. Participants underwent one-on-one semi-structured interviews and a second interview with the principal investigator to confirm findings. Interview analysis followed a substantive theory, within the grounded theory method. In this process, data collection, coding and analysis occur simultaneously and coding and analysis continue after the interview.

The central theme to emerge from the study was “resignation”, a conveyed awareness of their inability to return to a pre-cancerous lifestyle. Men adapted to the changes of having CaP. All participants focused on the bigger picture and this allowed them to coexist with a diagnosis of CaP. To focus on the bigger picture, they took into consideration past experiences, current state of affairs and hypothesized how potential outcomes would impact upon them. Family relations were prioritized, especially spousal communication. In addition, three sub-themes were identified; unaltered masculinity, the unimportance of PLS and erectile dysfunction as a speed bump. None of the men perceived changes in their own evaluation of masculinity after noticing PLS after RP. While men saw themselves as being unable to perform a “masculine” role in procuring coitus, this did not mean that they saw themselves as unmanly. The men also felt that PLS was unimportant, in part due to the fact that they all experienced erectile dysfunction. It is unclear how PLS might impact potent men in this regard. Finally, all men identified return of erectile function as the event that would improve satisfaction with penile function.

At the annual meeting of the Sexual Medicine Society of North America (SMSNA), Inc. in San Diego, Sciele Pharma, Inc., a Shionogi Company and Plethora Solutions Limited, a wholly owned subsidiary of Plethora Solutions Holdings PLC (“Plethora” AIM:PLE)., today presented data from its second positive pivotal study of PSD502 for the treatment of premature ejaculation (PE). Results of the double-blind treatment phase of this study, which enrolled patients from the U.S., Canada and Poland, are consistent with previously reported results of the pivotal trial conducted in Europe and showed that men who were treated with PSD502 five minutes before intercourse were able to delay ejaculation up to five times longer than those who used placebo. Additionally, patients and partners in both trials reported significant improvements in sexual satisfaction, and the drug was well tolerated.

An estimated one-third of U.S. men ages 18 – 59 are affected by PE, making it twice as prevalent as erectile dysfunction. Currently, there are no prescription therapies approved in the U.S. to treat PE.

PSD502, a product in development for the treatment of PE, is a proprietary formulation of the two marketed drugs lidocaine and prilocaine dispensed by a metered dose aerosol. PSD502 works selectively on non-keratinized skin on the glans penis (head of the penis).

“Premature ejaculation can have a powerful negative impact on the emotional and sexual lives of men and their partners,” said Professor Stanley E. Althof, PhD, Center for Marital and Sexual Health of South Florida, West Palm Beach, Florida. “Recently, the international sexual health community agreed that PE should be defined as ejaculation occurring within approximately one minute of penetration that causes the patient distress. Now we need to work to develop treatments, and these encouraging results with PSD502 seem to be a step in the right direction.”

Both pivotal trials showed clinically and statistically significant efficacy in the treatment of premature ejaculation, as measured by changes in Intravaginal Ejaculatory Latency Time (IELT) and Index of Premature Ejaculation (IPE), a patient-reported outcome of ejaculatory control, sexual satisfaction, and distress.

“We are excited that results from two pivotal studies have shown that PSD502 was effective for men with PE, and we look forward to the opportunity to help patients who have had no real options to date,” said Patrick Fourteau, Chief Executive Officer of Sciele Pharma, Inc. “This data will support the New Drug Application for PSD502 that we are planning to submit to the U.S. Food & Drug Administration (FDA), which upon FDA approval would make PSD502 be the first prescription treatment in the U.S. for premature ejaculation.”

Pivotal Study Details

The new study, the second of two major pivotal trials, was designed to assess the clinical benefit and safety of PSD502 in men with PE. The trial, which randomized 256 patients across 38 investigational centers in the U.S., Canada and Poland, also assessed the safety and tolerability of the therapy. Final analyses of the three months data confirmed that PSD502 produced a clinically and statistically significant increase from baseline in all study primary and secondary endpoints. The time for IELT for PSD502 group increased 4.7-fold compared to 1.5-fold in placebo (p<0.0001), resulting in a geometric mean IELT of 2.6 minutes in the PSD502 group and 0.8 minutes in the placebo group.

There were improvements in IPE scores in the PSD502 group, which recorded patient and partner feedback, compared to placebo, resulting in 5.0-, 4.6- and 2.5-point differences between PSD502 and placebo in ejaculatory control, satisfaction and distress domains, respectively (p<0.0001 between treatment comparisons).

Overall, PSD502 was well-tolerated, with no serious adverse events reported by patients or partners in the studies.

Also presented for the first time at SMSNA were two subset analyses of the European Phase III trial data showing:

– Increased ejaculatory latency and improvements in patent-reported outcomes seen in the first month of use with PSD502 were maintained over two to three months of treatment; and

– A significant positive correlation between mean IELT and IPE domain scores after three months of treatment, indicating that increases in IELT are associated with improvements in patient-reported outcomes.

About Premature Ejaculation

For years, various experts debated on the true definition of premature ejaculation. In 2008, the International Society for Sexual Medicine presented an evidence-based definition of PE as agreed upon by a consensus of the world’s leading sexual health experts: a male sexual dysfunction characterized by ejaculation which always or nearly always occurs prior to or within about one minute of vaginal penetration; and 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.