Porst_edit.qxp 21/10/08 10:00 Page 98
Premature Ejaculation
The Role of Pharmacotherapy in the Treatment of Premature Ejaculation
a report by
Hartmut Porst
Private Institute of Urology, Hamburg, and Associate Professor of Urology, University Hospital Bonn
Premature ejaculation (PE) is the most common male sexual disorder, with a committee for the definition of PE. Following a critical review of published
prevalence cited as being anywhere from 4 to 66%. It is accepted that data, the committee presented the following definition of lifelong PE:
around 25–40% of all men will suffer from PE at some point in their lives.
1
“Lifelong PE is a male sexual dysfunction characterised by ejaculation
Collecting epidemiological data on PE has been a complicated process, which always or nearly always occurs before or within about one minute
largely due to the various definitions of PE. The Diagnostic and Statistical of vaginal penetration, and the inability to delay ejaculation on all or nearly
Manual of Mental Disorders, 4th Edition (DSM-IV-TR), the International all vaginal penetrations, and negative personal consequences, such as
Consultation on Urological Disease (ICUD) and the American Urological distress, bother, frustration and/or the avoidance of sexual intimacy.”
8
Association (AUA) all present similar definitions in their guidelines, With insufficient published objective data, the panel decided that it was
considering that PE involves a short time interval between intromission and not possible to propose an evidence-based definition for acquired PE.
ejaculation, lack of control over ejaculation and sexual dissatisfaction by the However, the aim is that a more discriminating diagnostic tool can be
the patient and/or his partner(s).
2,3
The World Health Organization’s (WHO) devised by using a multivariate definition of PE using several diagnostic
10th edition of the International Classification of Diseases provides a criteria, such as patient-reported outcomes (PROs) and thereby control
quantitative measure, labelling PE as ejaculation that occurs before or within over ejaculation, rather than an IELT threshold.
15 seconds of initiating intercourse.
4
However, researchers have been largely
dissatisfied with these definitions, based as they are on subjective complaints Pathophysiology
and with a lack of clear, objective cut-off points for reliable experimentation. PE is categorised as either acquired or lifelong, with the former indicating
Some authors have defined PE using time, others based on the number of either a psychological or a secondary organic aetiology – such as
penile thrusts before ejaculation. The introduction of the ‘intravaginal prostatitis or thyroid disorders – and the latter a biogenic (neurobiologic)
ejaculatory latency time’ (IELT) by Waldinger and colleagues, an objective aetiology.
9
Alternatively, PE can be further defined by its occurrence, i.e.
parameter measuring the time from vaginal penetration to the start of whether it is situational (based on partners or conditions) or global
intravaginal ejaculation using a stop-watch operated by the partner, has (where the disorder exists regardless of circumstances).
introduced a more objective outcome measure to evidence-based studies of
PE.
5
Two larger-cohort studies in men with lifelong PE have shown that in The causes of PE are largely unknown. Although its pathogenesis is
the overwhelming majority (~90%) ejaculation occurs within one minute, obscure, five pathophysiological aspects have been ascribed to PE (see
with the remaining 10% ejaculating within two minutes.
6,7
Table 1), largely falling into two major classes: psychological or
neurobiological.
10
The original Masters and Johnson theory attributed a
In an attempt to derive an evidence-based definition of PE and thus reduce psychological basis to PE, explaining that it is a learned pattern maintained
the number of diagnostic errors, in 2007 the International Society of by performance anxiety.
11
Other theories have proposed a role for early
Sexual Medicine (ISSM) appointed 21 international experts to an ad hoc sexual experiences, sexual conditioning, sexual technique and frequency
of sexual intercourse.
12
PE has also been correlated with anxiety, and
significantly so with life stresses such as dissatisfaction with work or
Hartmut Porst is the Principal of a private urological and
andrological institute in Hamburg and holds an associate
trouble in personal relationships.
13,14
professorship in urology at the University Hospital in Bonn.
The main focus of his work is andrology, in particular
However, evidence from animal models has led to the development of a
erectile dysfunction, Peyronie’s disease, hormonal disorders
(the ageing male), plastic genital surgery and male
theory that PE is not psychological but rather has a neurobiological basis.
15,16
infertility. He has been involved in more than 55 clinical
There is an increasing body of evidence that serotonin is the major
trials in these areas, serving as the principal investigator in
neurotransmitter involved in ejaculation and emission, and it has been
more than 15 of them. Professor Porst is Chairman of the
Standards Committee of the International Society for Sexual Medicine (ISSM) and an active proposed that men with lifelong PE are suffering from either a congenital
member of numerous other associations, including the European Society for Sexual Medicine
hypofunction of the the 5-HT
2C
receptor or a hyperfunction of the 5-HT
1A
(ESSM), the European Association of Urology (EAU) and the International Society for the
Study of the Aging Male (ISSAM), and belongs to a variety of national and international
receptor, or both.
17
Further research is needed to clarify the exact role of the
expert boards. Professor Porst has published more than 30 books and book contributions serotonergic system in PE. Prostatic pathologies have also been suggested as
and more than 200 original papers in peer-reviewed journals. He is an Editorial Board
possible aetiologies of PE, as a significantly high rate of prostatic
member of the Journal of Sexual Medicine and serves as a regular reviewer for more than
15 international scientific journals.
inflammation or infection has been found in men with acquired PE
compared with a control population.
18
Hyperthyroidism has also been
E: porst20354@aol.ocm
associated with PE, with one study demonstrating that 50% of men with
Supported by an educational grant from Janssen Cilag. The views expressed are those of the author, and not necessarily those of Janssen Cilag.
98 © TOUCH BRIEFINGS 2008