The Dangers That Threaten Current Research of Premature Ejaculation: Using Validated Questionnaires, Performing Conjuring Tricks with Statistics, and Refusing to Use Real-time Stopwatch Measurements of Intravaginal Ejaculation Latency Time

Possible Pathophysiological Roles of Neurotransmitter Systems in Men With Lifelong Premature Ejaculation: Protocol for a Scoping Review

BACKGROUND

Lifelong premature ejaculation (LPE) is a rare sexual condition believed to be caused by genetic neurobiological disorders. In the field of LPE, 2 main types of research have been conducted: direct genetic research and pharmacotherapeutic interference of neurotransmitter systems that can relieve the symptoms of LPE in male patients.

OBJECTIVE

We aim to provide an overview of studies on neurotransmitter systems as the pathophysiological cause of LPE by investigating direct genetic research or pharmacotherapeutic interference that relieves the main symptom of LPE in male patients.

METHODS

This scoping review will use the PRISMA-ScR tool (Preferred Reporting Items for Systematic Reviews and Meta-Analyses extension for Scoping Reviews). In addition, this study will use a peer-reviewed search strategy. Systematic searches will be conducted using 5 scientific databases (Cochrane Database of Systematic Reviews, PubMed or MEDLINE, Cumulative Index to Nursing and Allied Health Literature [CINAHL], EMBASE, and Epistemonikos). Additionally, pragmatic searches for relevant information in gray literature databases will be performed. Two reviewers will independently include relevant studies in a 2-stage selection strategy. Finally, data will be extracted from the studies and charted to summarize relevant study characteristics and key findings.

RESULTS

As of July 2022, we completed the preliminary searches according to the PRESS 2015 guidelines and started to determine the final search terms that we will use in all selected 5 scientific databases.

CONCLUSIONS

This scoping review protocol is the first to focus on neurotransmitter pathways in LPE by combining the results from the genetic and pharmacotherapy studies. The results could help identify potential research gaps or target candidate proteins and neurotransmitter pathways in LPE for further genetic research.

TRIAL REGISTRATION

Open Science Framework 10.17605/OSF.IO/JUQSD; https://osf.io/juqsd.

INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID)

PRR1-10.2196/41301.

Anatomic maps of erogenous sensation and pleasure in the penis: are there difference between circumcised and uncircumcised men?

BACKGROUND

The effects of male circumcision on sexual function remain controversial. Heterogeneity across previous studies and low-quality scientific evidence have resulted in poor understanding of the effects of circumcision on erogenous sensation of the penis and orgasm function.

AIM

In this study we sought to describe and assess differences in erogenous genital sensation and reported orgasm function in circumcised compared with uncircumcised men.

METHODS

Adult male subjects who were recruited on a paid anonymous online survey platform were shown illustrations of 12 anatomic regions of the penis. Subjects were prompted to designate regions as pleasurable when touched during partnered sex and to rate each on a 1-10 scale, with higher erogeneity scores correlating with greater pleasure. Subjects were also asked to characterize their orgasms across 6 experiential domains.

OUTCOMES

Outcomes were differences between circumcised and uncircumcised men in the probabilities that regions would be designated as pleasurable, average pleasure scores, and self-reported orgasm parameters.

RESULTS

In total, 227 circumcised (mean [SD] age 46.6 [17.7] years) and 175 uncircumcised men (47.8 [18.1] years) completed the survey. There were no significant differences in average ratings across all regions between circumcised and uncircumcised men. However, significantly more circumcised men reported preferences for the tip of the penis (38% vs 17%, P = .02) and the middle third of the ventral penile shaft (63% vs 48%, P = .04). Additionally, there were no significant differences in orgasm quality and function across all queried domains between circumcised and uncircumcised cohorts.

CLINICAL IMPLICATIONS

Our findings suggest that circumcision does not change how men describe erogenous genital sensation or how they experience orgasm.

STRENGTHS AND LIMITATIONS

In this study we expanded upon existing literature regarding comparison of sexual function in circumcised and uncircumcised men in its scale and investigation of diverse domains. Limitations include the survey format of data collection.

CONCLUSION

We found no differences in reported erogenous ratings or orgasm function between circumcised and uncircumcised men. These findings suggest that male circumcision does not negatively impact penile erogeneity or orgasm function.

The pathophysiology of lifelong premature ejaculation

For many decades it has been thought that lifelong premature ejaculation (PE) is only characterized by persistent early ejaculations. Despite enormous progress of in vivo animal research, and neurobiological, genetic and pharmacological research in men with lifelong PE, our current understanding of the mechanisms behind early ejaculations is far from complete. The new classification of PE into four PE subtypes has shown that the symptomatology of lifelong PE strongly differs from acquired PE, subjective PE and variable PE. The phenotype of lifelong PE and therefore also the pathophysiology of lifelong PE is much more complex. A substantial number of men with lifelong PE not only have PE, but also premature erection and premature penile detumescence as part of an acute hypertonic or hypererotic state when engaged in an erotic situation or when making love. As both erectio praecox, ejaculatio praecox, detumescentia praecox, and the hypererotic state are part of the phenotype lifelong PE, it is argued that lifelong PE is not only a disturbance of the timing of ejaculation but also a disturbance of the timing of erection, detumescence and arousal. Since 1998, the pathophysiology of lifelong PE was thought to be mainly mediated by the central serotonergic system in line with genetic polymorphisms of specific serotonergic genes. However, by accepting that lifelong PE is characterized by the reversible hypertonic state the hypothesis of mainly serotonergic dysfunction is no longer tenable. Instead, it has been postulated that the pathophysiology of lifelong PE is mediated by a very complex interplay of central and peripheral serotonergic, dopaminergic, oxytocinergic, endocrinological, genetic and probably also epigenetic factors. Progress in research of lifelong PE can only be accomplished when a stopwatch is used to measure the IELT and the cut-off point of 1 minute for the definition of lifelong PE is maintained. Current use of validated questionnaires, neglect of stopwatch research, clinically inexperienced investigators and inclusion of anonymous men in a study performed by the Internet endanger the continuation of objective research of lifelong PE.