29

Premature Ejaculation

Chris G. McMahon

Introduction

Over the past 20–30 years,the PE treatment para­ digm, previously limited to behavioral psy­ chotherapy, has expanded to include drug treatment.1,2 Animal and human sexual psychop­ harmacological studies have demonstrated that serotonin and 5­HT receptors are involved in ejaculation and confirm a role for SSRIs in the treatment of PE.3­6 Multiple well­controlled evi­ dence­based studies have demonstrated the effi­ cacy and safety of SSRIs in delaying ejaculation, confirming their role as first­line agents for the treatment of lifelong and acquired PE.7 More recently,there has been increased attention to the psychosocial consequences of PE, its epidemiol­ ogy, its etiology, and its pathophysiology by both clinicians and the pharmaceutical industry.8­13

poorly validated definitions of PE.11,13,19 A multi­ national, community­based, age­ranging stop­ watch IELT study demonstrated that the distribution of the IELT was positively skewed, with a median IELT of 5.4 min (range, 0.55–44.1 min), decreased with age, and varied between countries.10 (Fig. 29.1) Using an epidemiological approach to assess PE risk, the authors regarded the 0.5 and 2.5 percentiles as acceptable stan­ dards of disease definition in this type of skewed distribution, and proposed that men with an IELT of less than 1 min (belonging to the 0.5 percentile) have “definite” PE, while men with IELTs between 1 and 1.5 min (between 0.5 and 2.5 percentile) have “probable” PE.20 These nor­ mative data support the notion that IELTs of less than 1 min are statistically abnormal compared to men in the general Western population.

Epidemiology

Premature ejaculation (PE) has been estimated to occur in 4–39% of men in the general com­ munity.12,14­19 and is often reported as the most common male sexual disorder, despite a sub­ stantial disparity between the self­reported inci­ dence of PE in epidemiological studies19 and that suggested by community­based normative stopwatch intravaginal ejaculation latency time (IELT) studies.10 However, most epidemiological studies are limited by their reliance on either patients’ self­reporting of PE or inconsistent and

Classification of Premature

Ejaculation

The population of men with PE is not homoge­ nous. In 1943, Schapiro classified PE as either primary (lifelong) or secondary (acquired).21 Recently, Waldinger et al. expanded this classifi­ cation to include lifelong PE, acquired PE, natu­ ral variable PE, and premature­like ejaculatory dysfunction (Table 29.1).22 Lifelong PE is a syn­ drome characterized by a cluster of core symp­ toms including early ejaculation at nearly every intercourse within 30–60 s in the majority of

C.R. Chapple and W.D. Steers (eds.), Practical Urology: Essential Principles and Practice,	385
DOI: 10.1007/978-1-84882-034-0_29, © Springer-Verlag London Limited 2011

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Practical Urology: EssEntial PrinciPlEs and PracticE

Number of men

100

80

60

40

20

0

0	200	400	600	800	1,000	1,200	1,400	1,600	1,800	2,000	2,200	2,400	2,600	2,800
						Mean IELT (s)

Figure 29.1. distribution of intravaginal ejaculatory latency times (iElt) values in a random cohort of 491 men (reprinted from Waldinger et al.10 copyright 2005.With permission from Wiley via copyright clearance center rightslink).

Table 29.1. the four premature ejaculation (PE) syndromes (data from Waldinger22)
Variable	Lifelong premature	Acquired premature	Natural variable	Premature-like
	ejaculation	ejaculation	premature ejaculation	ejaculatory
				dysfunction
iElt	Very short iElt	(Very) short iElt	normal iElt	normal or long iElt
	(<1–1.5 min)	(<1.5–2 min)	(3–8 min)	(3–30 min)
Frequency	consistent	(in)consistent	inconsistent	(in)consistent
Etiology	neurobiological and	Medical and/or	normal variation of	Psychological
	genetic	psychological	ejaculatory
			performance
treatment	Medication with or	Medication and/or	Psychoeducation,	Psychotherapy
	without counseling	psychotherapy	reassurance
Prevalence	low (?)	low (?)	High (?)	High (?)

IELT intravaginal ejaculation latency time22.

cases (80%) or between 1 and 2 min (20%), with every or nearly every sexual partner and from the first sexual encounter onwards. Acquired PE differs in that sufferers develop early ejaculation at some point in their life having previously had normal ejaculation experiences. Acquired PE may be due to sexual performance anxiety,23 psychological or relationship problems,23 erec­ tile dysfunction (ED),24 prostatitis,25 hyperthy­ roidism,26 or during withdrawal/detoxification from prescribed27 or recreational drugs.28 In a study of 1,326 consecutive men with PE, lifelong

PE was present in 736 men (74.4%),and acquired PE was present in 253 men (25.6%).29 In natural variable PE, the ejaculation time is never consis­ tently rapid but merely coincidental and situa­ tional. This type of PE should be regarded as a normal variation in sexual performance and is characterized by inconsistent and irregular early ejaculation, often with reduced ejaculatory con­ trol.30 Men with premature­like ejaculatory dys­ function complain of PE but have a normal ejaculatory latency of 3–6 min. It is character­ ized by a pre­occupation with a subjective but

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PrEMatUrE EjacUlation

	false perception of PE with an ELT within the				within 1 min.29,46,47 Waldinger et al. (1998)
	normal range but often with reduced ejacula­				reported IELTs <30 s in 77% and <60 s in 90% of
	tory control.				110 men with lifelong PE with only 10% ejacu­
					lating between 1 and 2 min.46 McMahon et al.
					reported similar results in 1,346 consecutive
	Defining Premature Ejaculation				men with predominant ante portal ejaculation
					(during foreplay) in 5.6% of men.29 As such, an
	Research into the treatment and epidemiology of				IELT cut­off of 1 min captures 90% of treatment­
					seeking men with lifelong PE. Further qualifica­
	PE is heavily dependent on how PE is defined.
					tion of this cut­off to “about 1 min” affords the
	The medical literature contains several univariate
					clinician sufficient flexibility to also diagnose
	and	multivariate	operational	definitions of
					PE in the 10% of PE treatment seeking men who
	PE.2,20,31­37 Although the most commonly quoted
					ejaculate within 1–2 min of penetration without
	definition, DSM­IV­TR, and other definitions of
					unnecessarily stigmatizing the remaining 90%
	PE differ substantially, they are all authority
					of men who ejaculate within 1–2 min of pene­
	based, i.e., expert opinion without explicit critical
					tration but have no complaints of PE. In office
	appraisal,38 rather than evidence­based and have
					practice, the IELT can be reliably estimated by
	no support from controlled clinical and/or epide­
					men with PE. Several authors report that esti­
	miological studies. This lack of agreement as to
					mated and stopwatch IELT correlate reasonably
	what	constitutes	PE has hampered clinical
					well or are interchangeable in assigning PE sta­
	research into the etiology and management of
					tus when estimated IELT is combined with
	this condition, and the development of patient
					patient reported outcomes (PROs).48­50
	reported outcomes (PROs) to diagnose and assess
	treatment intervention strategies.39 The first mul­
	tivariate evidence­based definition of lifelong PE				Voluntary Control
	was recently reported and characterizes lifelong
	PE as “… ejaculation which always or nearly
	always occurs prior to or within about one min­				The ability to prolong sexual intercourse by
	ute of vaginal penetration, the inability to delay
					delaying ejaculation and the subjective feelings
	ejaculation on all or nearly all vaginal penetra­
					of ejaculatory control comprise the complex
	tions, and the presence of negative personal con­
					construct of ejaculatory control. Virtually all
	sequences, such as distress, bother, frustration
					men report using at least one cognitive or behav­
	and/or the avoidance of sexual intimacy.”40 There
					ioral technique to prolong intercourse and delay
	is insufficient published evidence to propose an
					ejaculation, with varying degrees of success, and
	evidenced­based definition of acquired PE.40
					many young men reported using multiple dif­
					ferent techniques.18
	Intravaginal Ejaculatory Latency				Several authors have suggested that an inabil­
					ity to voluntarily defer ejaculation defines PE.51­54
	Time (IELT)				Patrick et al. reported ratings of “very poor” or
					“poor”for control over ejaculation in 72% of men
					with PE compared to 5% in a group of normal
	Operationalization of PE measuring the length				controls.11 However, control is a subjective mea­
	of time between penetration and ejaculation				sure that is difficult to translate into quantifiable
	with a stopwatch, the intravaginal ejaculatory				terms and is the most inconsistent dimension of
	latency time (IELT), forms the basis of most cur­				PE. Grenier and Byers failed to demonstrate a
	rent clinical studies on PE.41 There is consider­				strong correlation between ejaculatory latency
	able variance of the latencies used to identify				and subjective ejaculatory control.18,55 Several
	men with PE with IELTs ranging from 1 to 7 min				authors report that diminished control is not
	and none of the definitions is based on norma­				exclusive to men with PE and that some men
	tive data or offer any supportive rationale for				with a brief IELT report adequate ejaculatory
	their proposed cut­off time.42­45				control and vice versa,suggesting that the dimen­
	Several studies suggest that 80–90% of men				sions of ejaculatory control and latency are dis­
	seeking treatment		for lifelong	PE ejaculate	tinct concepts.11,18

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Practical Urology: EssEntial PrinciPlEs and PracticE

Contrary to this, several authors have	showed that men with PE had significantly lower
reported a moderate correlation between the	overall health­related quality of life and lower
IELT and the feeling of ejaculatory con­	Self­Esteem And	Relationship	Questionnaire
trol.11,50,56,57 Rosen et al. report that control over	(SEAR) scores with lower confidence and self­
ejaculation, personal distress, and partner dis­	esteem compared	to non­PE	groups (all
tress was more influential in determining PE	p £0.001).60 The divergent pattern observed for
status than IELT.50 However, despite conflicting	personal distress suggests that this construct has
data on the relationship between control and	discriminative validity in diagnosing men with
latency, the balance of evidence supports the	and without PE. The data for satisfaction and
notion that the inability to delay ejaculation	interpersonal distress while statistically signifi­
appears to differentiate men with PE from men	cant were not as strong.
without PE.11,57,58

Sexual Satisfaction

Men with PE report lower levels of sexual satis­ faction compared to men with normal ejacu­ latory latency. However, caution should be exercised in assigning lower levels of sexual sat­ isfaction solely to the effect of PE and contribu­ tions from other difficult­to­quantify issues such as reduced intimacy, dysfunctional rela­ tionships, poor sexual attraction, and poor com­ munication should not be ignored. This is supported by the report of Patrick et al. that despite reduced ratings for satisfaction with shorter IELTs with “poor” or “very poor” inter­ course satisfaction reported by 25.4%, 3.6%, and 2.0% of subjects with an IELT <1 min, >1 min, and >2 min, respectively, a substantial propor­ tion of men with an IELT <1 min report “good” or “very good” satisfaction ratings (43.7%). Current data are limited but suggests that sexual satisfaction is of limited use in differentiating PE subjects from non­PE subjects and has not been included in the ISSM definition of PE.11

Distress

Premature ejaculation (PE) has been associated with negative psychological outcomes in men and their partners.9,11,12,23,57­67 The personal and/ or interpersonal distress that result from PE may affect men’s quality of life and partner relation­ ships, their self­esteem and self­confidence, and can act as an obstacle to single men forming new partner relationships.9,11,12,23,57­67 Patrick et al. reported that 64% of men with PE versus 4% of non­PE men reported being “quite a bit” or “extremely” personally distressed. Rowland et al.

The Etiology of Premature

Ejaculation

Historically, attempts to explain the etiology of PE has included a diverse range of biological and psychological theories. Most of these pro­ posed etiologies are not evidence based and are speculative at best. Psychological theories include the effect of early experience and sexual conditioning, anxiety, sexual technique, the fre­ quency of sexual activity, and psychodynamic explanations. Biological explanations include evolutionary theories, penile hypersensitivity, central neurotransmitter levels and receptor sensitivity, degree of arousability, the speed of the ejaculatory reflex, and the level of sex hormones.

There is little empirical evidence to suggest a causal link between PE and any of the factors thought to cause PE. There is, however, limited correlational evidence to suggest that lifelong PE is genetically determined and related to the inherited altered sensitivity of central 5­HT receptors and acquired PE is due to high levels of sexual anxiety, ED, or lower urinary tract infection.

Ejaculatory latency time is probably a biologi­ cal variable, which is genetically determined and may differ between populations and cultures, ranging from extremely rapid through average to slow ejaculation. This is supported by animal studies showing a subgroup of persistent rapidly ejaculating Wistar rats,6 an increased familial occurrence of lifelong PE,5and a moderate genetic influence on PE in the Finnish twin study.68 Hyposensitivity of the 5­HT2C and/or hypersen­ sitivity of the 5­HT1A receptors have been sug­ gested as a possible explanation of lifelong PE.69,70