Prevalence and correlates of premature ejaculation in a primary care setting: a preliminary crosssectional study

Prevalence and Correlates of Premature Ejaculation in a Primary
Care Setting: A Preliminary Cross-Sectional Studyjsm_22801.8

Wei Shuong Tang, MMed* and Ee Ming Khoo, MD† *Bayan Baru Health Clinic, Bayan Baru, Penang, Malaysia; †Department of Primary Care Medicine, University of Malaya,Kuala Lumpur, Malaysia A B S T R A C T
Introduction. Premature ejaculation (PE) is common. However, it has been underreported and undertreated.
Aims. To determine the prevalence of PE and to investigate possible associated factors of PE.
Methods. This cross-sectional study was conducted at a primary care clinic over a 3-month period in 2008. Men aged
18–70 years attending the clinic were recruited, and they completed self-administered questionnaires that included
the Premature Ejaculation Diagnostic Tool (PEDT), International Index of Erectile Function, sociodemography,
lifestyle, and medical illness. The operational definition of PE included PE and probable PE based on the PEDT.
Main Outcome Measure. Prevalence of PE.
Results. A total of 207 men were recruited with a response rate of 93.2%. There were 97 (46.9%) Malay, 57 (27.5%)
Chinese, and 53 (25.6%) Indian, and their mean age was 46.0 Ϯ 12.7 years. The prevalence of PE was 40.6%
(N = 82) (PE: 20.3%, probable PE: 20.3% using PEDT). A significant association was found between ethnicity and
PE (Indian 49.1%, Malay 45.4%, and Chinese 24.6%; c2 = 8.564, d.f. = 2, P = 0.014). No significant association was
found between age and PE. Multivariate analysis showed that erectile dysfunction (adjusted odds ratio [OR] 4.907,
95% confidence interval [CI] 2.271, 10.604), circumcision (adjusted OR 4.881, 95% CI 2.346, 10.153), sexual
intercourse Յ5 times in 4 weeks (adjusted OR 3.733, 95% CI 1.847, 7.544), and Indian ethnicity (adjusted OR 3.323,
95% CI 1.489, 7.417) were predictors of PE.
Conclusion. PE might be frequent in men attending primary care clinics. We found that erectile dysfunction,
circumcision, Indian ethnicity, and frequency of sexual intercourse of Յ5 times per month were associated with PE.
These associations need further confirmation. Tang WS and Khoo EM. Prevalence and correlates of premature
ejaculation in a primary care setting: A preliminary cross-sectional study. J Sex Med **;**:**–**.

Key Words. Patient-Reported Outcome Measures for Premature Ejaculation; Premature Ejaculation; Prevalence;
Primary Health Care
Introduction
The DSM-IV-TR [6] defines PE as “a persis- tent or recurrent ejaculation with minimal sexual P remature ejaculation (PE) is a common male stimulationbefore,on,orshortlyafterpenetration sexual dysfunction. The prevalence ranged and before the person wishes it and it causes between 21% and 66% in the community [1–3] marked distress or interpersonal difficulty and is not due to the direct effects of a substance.” Various definitions have been used to define PE, Currently, there are five validated tools that are and these include: the Diagnostic and Statistical used to assess PE: the five-item Premature Ejacu- Manual of Mental Disorders, Fourth Edition, Test lation Diagnostic Tool (PEDT) [9,10]; the Prema- Revision (DSM-IV-TR) [6]; the 10th revision of ture Ejaculation Profile [11], which used the the International Classification of Diseases-10 [7]; DSM-IV-TR classification criteria; the 10-item and the evidence-based definition from the Inter- Chinese Index of Premature Ejaculation [12], national Society for Sexual Medicine [8].
which was developed as an efficacy measure but 2011 International Society for Sexual Medicine did not specifically address the DSM-IV-TR cri- stress, the options were “a lot,” “somewhat,” teria; the Arabic questionnaires [13]; and the Index of Premature Ejaculation [14]. Among these tools, The PEDT consists of five questions that the PEDT was found to have a high level of agree- address the following five domains: ejaculation ment with the clinical diagnosis, and its test–retest control; frequency of PE; ejaculation with minimal reliability was good with an intraclass correlation sexual stimulation; distress; and interpersonal dif- ficulty. Each question has five responses, and the PE is associated with age, lifestyle [16], and scores of each question range from 0 to 4 with a comorbidities such as depression [17], anxiety minimum total score of 0 to a maximum score of [17,18], social phobia [19,20], diabetes [21], pros- 20. A low score suggests a low probability of tate diseases [22–24], and erectile dysfunction (ED) having PE. The total scores are categorized into: [25]. Despite PE being common, very few studies “no PE” (Յ8), “probable PE” (9–10), and “PE” have been conducted in the primary care setting.
(Ն11). In our study, the operational definition of This study aimed to determine the prevalence of PE included “PE” and “probable PE.” PE using PEDT and to identify possible associated Two versions of PEDT were used: the original factors of PE among primary care clinic attendees.
English version and the translated Malay ver-sion. The PEDT was translated into the Malaylanguage using the forward and backward transla- tion process, and it was done independently We conducted a cross-sectional study in the by two postgraduate family medicine trainees who primary care clinic at the University Malaya are bilingual. The back-translated English version Medical Center (UMMC), which is a teaching was compared with the original English version, university hospital in Kuala Lumpur, Malaysia.
and further revisions were made. The final Malay Ethics approval was obtained from the UMMC version of the PEDT was sent to the copyright Medical Ethics Committee prior to commence- owner for approval to be used in the study.
A convenience sampling method was used.
having attempted sexual intercourse in the past 4 weeks [26]. Therefore, in this study, the IIEF-5 between June and August 2008 were approached was completed only by participants who had and recruited in this study. The reasons for sexual intercourse in the past 4 weeks. Men who encounter were chronic disease follow-up; treat- did not have sexual intercourse in the past 4 ment for acute conditions such as infection or weeks were asked to self-report whether they injury; and undifferentiated problems. They have ED. The operational definition of ED in might or might not have men’s health issues. The this study included men with IIEF-5 scores of inclusion criteria were: all men aged 18–70 years (Malaysian national language); had experience of A pilot study was conducted with 15 men, and sexual intercourse; and were currently not taking the questionnaires were pretested. Minimal adjust- a selective serotonin reuptake inhibitor. Informed ment was made. The sample size was calculated consent was obtained from those who agreed to using Epi Info version 6 (Centers for Disease participate in the study. The participants were Control and Prevention, Atlanta, GA, USA). Based asked to complete a set of self-administered ques- on an estimated PE prevalence of 30% with 95% tionnaires in English or Malay language, and confidence interval and taking into account a they consisted of: questions on sociodemography, refusal rate of 20%, the estimated sample size was lifestyle, medical conditions, and sexual history; International Index of Erectile Function-5 (IIEF- Data were analyzed using the SPSS 15.0 (SPSS 5); and PEDT. The participants were asked to Inc., Chicago, IL, USA) software [27]. Chi-square self-report whether they had any of the following test was used to determine the associations between categorical variables. The significance demia, diabetes mellitus, prostate disease, insom- level (a) was set at 0.05. Odds ratio was calculated nia, depression, and anxiety. For question on to examine the strength of the associations. Mul- exercise, the participants were given options of tivariate analysis was used to examine the net effect “never,” “<4 times/month,” “1–3 times/week,” or of independent variables on PE and to determine “Ն4 times/week,” while for the question on Premature Ejaculation and Associated Factors Background sociodemographic characteristics, health, lifestyle, and sexual behavior of the respondent A total of 245 men were approached to participatein the study, of which 222 patients fulfilled the inclusion criteria and 207 men consented. Theresponse rate was 93.2%. The mean age of the participants was 46.0 Ϯ 12.7 years, and the major- ity was Malays followed by Chinese and Indians.
The majority of the respondents were employed, married, and sexually active. Most respondents had sexual intercourse in the last 4 weeks. The majority had average to very high libido, and the 5.2 Ϯ 5.4 per 4 weeks (see Table 1). Based on the IIEF-5, 127 (61.4%) men had ED. Forty (19.3%) patients who did not have sexual intercourse in the past 4 weeks were asked to answer the question on self-reported ED; 17 of the 40 (42.5%) men self- reported ED. In this study, ED included men with reported ED, with an overall prevalence of 69.6%.
The prevalence of PE using the study opera- tional definition was 40.6% (N = 84) (probable PE [N = 42, 20.3%] and PE [N = 42, 20.3%] based on the PEDT). No significant association was found between PE and age groups (c2 = 1.406, d.f. = 4, PE was found to be significantly associated with ethnicity, circumcision, ED, and frequency of sexual intercourse using univariate analysis (Table 2). Using binary logistic regression (back- ward logistic regression [LR] method), ED, cir- cumcision, sexual intercourse (Յ5 times per 4 weeks), and Indian ethnicity were predictive factors Discussion
Sexual intercourse within last 4 weeks 167 (80.7)Libido/sexual interest Using the study operational definition, the preva- lence of PE among men who attended a teaching hospital-based primary care clinic was 40.6%.
This was consistent with the findings from other studies, which reported the prevalence of PE ranging from 21% to 66% [1–3], including a study done in a Malaysia urban population where the prevalence of self-reported PE was 22.3% [16].
We included “probable PE” from the PEDT inthe operational definition as it is known that men Indian ethnicity was found to be significantly underreport their sexual problems and do not seek associated with PE. The multi-country concept medical help [28]. If the “PE” category alone was evaluation and assessment of PE incidence study examined, the prevalence of 20.3% was consistent have shown substantial geographical variation in with the findings of self-reported PE in the previ- the perception of how long it takes for the ous study [16]. It is likely the probable PE category “average” man to ejaculate [29]. The difference in of the PEDT was mild and was not perceived by perception of normal intravaginal ejaculatory latency time (IELT) may cause difference in per- Figure 1 Prevalence
ejaculation according to age groups.
ception of poor control of ejaculation and related mechanism of this relationship is yet to be charac- distress, and hence the problem of PE. These terized but may include reduced performance variations could be because of differences in reli- anxiety, a higher ejaculatory threshold, or superior gion, awareness of sexual dysfunction, ability to ejaculatory control because of earlier and superior admit sexual failure, and cultural perception on the recognition of prodromal ejaculatory sensations.
importance of sex [30]. This ethnic difference Among the medical illnesses, ED was the only requires further studies for confirmation.
condition that had shown a significant association We found that circumcision was independently with PE. This corresponded with the Jannini et al.
associated with PE. This finding was consistent study that found that ED may be a comorbid, a with the O’Hara and O’Hara study [31], where cause, or an effect of PE [25]. Many men may find women reported that their circumcised male it confusing to differentiate between PE and ED, partners were more likely to have PE than the as was demonstrated in the Global of Study of uncircumcised partners. The thickening and kera- Sexual Attitudes and Behaviors [1]. It is therefore tinization of the glans penis mucosal epithelium important to further evaluate these conditions as after circumcision may be responsible for the dif- ference in the sensory threshold of the glans penis.
No significant association was found between The nerves of the glandis corona may be hyper- age and PE. This finding was similar to that found stimulated during intercourse and hence trigger in the PE Prevalence and Attitudes survey [3] and ejaculation before it is desired [32]. However, the prevalence study of sexual dysfunction in the there were prospective studies [33,34] that exam- United States [2]. The prevalence of PE is similar ined sexual function before and after circumcision, across the age groups, while the prevalence of ED and found that circumcision did not appear to have increases with age [38,39]. Anxiety and depression an adverse effect. Waldinger et al. [29] also did not were not found to be significantly associated with find any significant difference in the median IELT PE in the study as was noted in others’ studies between circumcised and not circumcised men in [16,17]. This may be because of the small number five countries excluding Turkey. Further studies of respondents with anxiety and depression in this study. In addition, the self-reported dichotomous Frequency of sexual intercourse of Յ5 times in scale of “yes” or “no” response for these conditions 4 weeks was also found to be significantly associ- may not reflect the prevalence of the disease.
ated with PE. It is likely that men with PE would This study was limited by enrolling patients have less sexual intercourse, or it could also be who understood either English or the Malay lan- plausible that infrequent sexual intercourse con- guage. However, as this study was done at an urban tributed to PE. The relationship between ejacula- tertiary hospital, most patients were literate in Malay or English. Nevertheless, this study could intercourse is conflicting. While the study of Jang be further improved if other languages such as [35] and Spiess et al. [36] reported that the fre- Tamil and Mandarin versions of the questionnaires quency of sexual activity in men with PE was are made available in this multicultural society.
lower than age-matched controls with normal This study was also limited by its cross-sectional ejaculatory control, in contrast, Strassberg et al.
design, and it was conducted in a hospital-based [37] failed to demonstrate any relationship. The primary care practice. Thus, the findings may not Premature Ejaculation and Associated Factors Associated factors of premature ejaculation PE = premature ejaculation; OR = odds ratio; CI = confidence interval; BMI = body mass index.
be generalizable. However, it provides an insight PE and need treatment in the long term. In addi- to this condition in the primary care setting, which tion, studies using the latest evidence-based defi- was lacking. A longitudinal study can be done for nition of PE by the International Society for men with probable PE to evaluate if they develop Sexual Medicine Committee [40] can be used in Independent associated factors of PE using multiple logistic regression PE = premature ejaculation; SE = standard error; OR = odds ratio; CI = confidence interval.
the primary care setting to further evaluate this Bayan Baru, George Town, Penang 11950, Malaysia.
common male sexual dysfunction. PE is defined as “a male sexual dysfunction characterized by ejacu- lation which always occurs prior to or within about one minute of vaginal penetration, and the inabil-ity to delay ejaculation on all or nearly all vaginalpenetrations, Statement of Authorship
quences.” Studies have indicated that patients’ or partner’s self-reported ejaculatory latency time (a) Conception and Design
correlates relatively well with the objective stop- watch latency time [40–42]. Thus, patients and/or (b) Acquisition of Data
their partners with probable PE and PE can be further evaluated based on their self-reported (c) Analysis and Interpretation of Data
IELT rather than the stopwatch latency time. The self-reported IELT is more applicable in theprimary care settings and can help primary care physicians to decide on the treatment plan [43].
(a) Drafting the Article
Dapoxetine, an on-demand short-acting serotonin selective reuptake inhibitor, has been shown to (b) Revising It for Intellectual Content
improve the IELT and can be used to treat PE[44–46].
Category 3
(a) Final Approval of the Completed Article
Conclusion
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