Prevalence of prostatitis-like symptoms in outpatients with four premature ejaculation syndromes: a study in 438 men complaining of ejaculating prematurely

Abstract

Objective: To evaluate the incidence of prostatitis-like symptoms (PLS) in men with or without PE, and the differences among the 438 outpatients with the four PE syndromes. Subjects and methods: Between January 2012 and January 2013, 438 consecutive heterosexual men complaining of PE and another 493 male healthy subjects without the complaint were included in this study. Each of them completed a detailed face-to-face questionnaire for information of demographics, National Institutes of Health-Chronic Prostatitis Symptom Index (NIH-CPSI), and International Index of Erectile Function-5 (IIEF-5). Each patient was classified as one of the four PE subtypes: lifelong PE (LPE), acquired PE (APE), natural variable PE (NVPE), or premature-like ejaculatory dysfunction (PLED). Results: There were no significant difference between patients and control subjects regarding demographics. In the PE group, the prevalence of PLS were 32%, showing statistical significance compared with control subjects (15.8%, P<0.001). And the NIH-CPSI score was 10.0±7.9, showing significant difference compared with control subjects (6.0± 5.4, P<0.001). Among the four PE syndromes, patients with PLED had the highest prevalence of PLS (42.3%, P<0.001), but the difference of NIH-CPSI scores among the four PE syndromes was not significant (P=0.055). Conclusions: PLS were more common in patients with PE. Also, patients had worse NIH-CPSI scores than the control subjects. Therefore, patients with PLED had the highest incidence of PLS.

Introduction

Chronic prostatitis (CP) is a common disease affecting 30-40% of sexually active men in an age-dependent manner and it commonly presents as chronic pelvic pain syndrome (CPPS) [1], which is poorly understood, inadequately treated, and has a high rate of recurrence [2]. It is generally acknowledged that CP is a common cause of complaint among adult men, but information on the prevalence of CP is hindered by the confusion over its definition and debate over the relative importance of histopathological, clinical, and symptom-related definitions [3]. The National Institutes of health chronic prostatitis symptom index (NIH-CPSI) were used to describe Prostatitis-Like Symptoms (PLS). Although it was not a diagnostic standard of CP, the location and level of pain according to the NIH-CPSI would be sufficient to lead most physicians to make a diagnosis of CP [1]. Liang et al. reported an 8.4% incidence of PLS and a 4.5% incidence of CP in Chinese men [2]. Despite its unclear pathogenesis, it was considered to lead to an impaired quality of life, such as premature ejaculation (PE) etc.

PE is one of the most common sexual dysfunctions, affecting 30-40% of sexually active men, and perhaps as many as 75% of men at some point in their lives [4-7]. There are various definitions of PE made by different professional organizations. The International Society for Sexual Medicine (ISSM) established the first evidence-based definition of PE in 2007. The committee defined lifelong PE as “a male sexual dysfunction characterized by ejaculation which always or nearly always occur prior to or within the first minute of vaginal penetration and the 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” [8]. Although the new evidence-based definition of PE was published, clinicians would often come into contact with patients seeking assistance for PE who did not meet the diagnostic criteria. This situation suggested that the new definition of PE did not include all forms of PE. To address this issue, Waldinger and Schweitzer proposed a new classification scheme for PE that was based on the duration of ejaculation time, frequency of complaints, and course of the disorder over the lifetime of the patient. In addition to the subtypes of lifelong PE (LPE) and acquired PE (APE), they added the natural variable PE (NVPE) and premature-like ejaculatory dysfunction (PLED) subtypes [9-11].

Recently, the prevalence of CP in patients with PE, and that of PE in men suffering from CP, has been studied [6,12], which suggested a possible relationship between them. On the other hand, CP or PLS has also been suggested to be an important organic cause of PE [13]. However, currently there are no studies that have systematically evaluated the incidence of CP or PLS in the new proposed four PE syndromes and their possible associations. To understand the coexistence of these poorly understood conditions better and to correlate PLS with the specific subtypes of PE, we designed a study to examine the prevalence rate of PLS in patients with the four PE syndromes.

Subjects and methods

Subjects

Patients from our outpatient clinics of the First Affiliated Hospital of Anhui Medical University in Hefei, Anhui, China, who complained of PE were recruited from January 2012 until January 2013. A total of 438 consecutive heterosexual men aged 17-65 years (mean age 35.9±7.1 years), complaining of PE and attempting intercourses once or more per week, were enrolled in the study. To be included in the study, subjects had to meet the following criteria: (1) in a heterosexual, stable, and monogamous sexual relationship with the same female partner for >6 months; (2) without any major psychiatric or somatic disorder, and had not consumed any drug that could affect sexual function, or used antibiotics during the previous 3 weeks; (3) with an IIEF-5 score ≥22 indicating normal erectile function. Another 493 male healthy volunteers (age range 17-62 years; mean age 36.6±8.8 years) without the complaint of PE or other sexual dysfunction from our medical examination center for healthy physical examination were recruited as a control group. All control subjects were having a regular sexual relationship and reporting good control of ejaculation. Other exclusion measures were the same as for the patients.

Before the survey, a pre-survey was completed by 30 subjects to refine the survey questions and to improve their clarity. This study was approved by the Anhui Medical University Research Subject Review Board.

Study design and procedure

All patients and control subjects provided informed consent before their participation in this study. The questionnaire included demographics (weight, height, age, marital status, smoking, drinking, duration of relationship, educational status, and monthly income), sexual function, past medical history, expressed prostatic secretions (EPS) evaluation, and score of the Chinese version of the National Institute of Health Chronic Prostatitis Symptom Index (NIH-CPSI) and International Index of Erectile Function (IIEF-5), as well as self-estimated intravaginal ejaculatory latency time (IELT). For PE, according to Waldinger’s criteria of definition and classification, we summarized symptoms for the four PE syndromes (Table 1), and patients were divided into four groups: LPE, APE, NVPE, and PLED [9-11,14]. The IELT was the interval between the start of vaginal intromission and the start of intravaginal ejaculation.

Table 1.

Summary of the symptoms of four premature ejaculation syndromes used in the classification of males with complaints of ejaculating prematurely proposed by Waldinger [9]

Lifelong PE	Acquired PE	Natural variable PE	Premature-like ejaculation dysfunction
1. In the majority of cases (90%) within 30-60 s, or between 1-2 min (10%)	1. At some point in a man’s life	1. Ejaculation time may be short or normal	1. Subjective perception of consistent or inconsistent rapid ejaculation
2. Too early at nearly every intercourse	2. Usually a normal ejaculation experiences before the start of complaints	2. Being inconsistent and occurring irregularly	2. Preoccupation with an imagined early ejaculation or lack of control of ejaculation
3. From about the first sexual intercourse	3. With a sudden or gradual onset	3. The impression of diminished control of ejaculation	3. With a normal range or may even a longer IELT
4. With nearly every woman	4. The dysfunction may be results of urological dysfunctions, thyroid dysfunction, psychological or relationship problems	4. Diminishing the ability to delay ejaculation	4. The preoccupation is not better accounted for by another mental disorder
5. Lacking the ability to delay ejaculation	5. Lacking the ability to delay ejaculation		5. Diminishing the ability to delay ejaculation

Main outcome measures

In this study, PE was defined as admitting to a urology outpatient clinic with a self-reported complaint of ejaculating prematurely according to Waldinger et al. And it was divided into four PE syndromes based on the new classification [9,10]. A self-reported questionnaire was used to assess demographic measures, sexual function, medical and sexual history, as well as self-estimated IELT. PLS and ED were assessed by NIH-CPSI and IIEF-5, respectively.

NIH-CPSI is composed of pain, urinary symptoms, and quality of life impact. The pain score ranges from 0 to 21, and was calculated by totaling the scores of: location (a dichotomized value, 0=no and 1=yes, to having pain in the perineum, testicles, tip of penis, or in the pubic or bladder area); type, including a similar dichotomized value to having pain or burning on urinating or pain or discomfort during ejaculation; frequency of pain (0=never, 1=rarely, 2=sometimes, 3=often, 4=usually, and 5=always); and severity of average pain (range from 0=no pain to 10=pain as bad as you can imagine) [1].

IIEF-5 is composed of five items, including: confidence of getting and keeping an erection; difficulty grade of maintaining an erection to completion of intercourse; frequency of erections hard enough for penetration; maintaining erection after penetration; and satisfaction with intercourse. Each item has a score ranging from 1 to 5, and the possible scores for the IIEF-5 range from 5 to 25.

PLS were defined by the criteria of Nickel et al., including perineal and/or ejaculatory pain or discomfort, and a total index pain score of 4 or greater. Mild symptoms were defined by pain scores of 4 to 7, and moderate or severe symptoms by scores of 8 or greater [1]. Symptoms were divided into mild, moderate, and severe, corresponding to the total NIH-CPSI scores of 0-14, 15-30, and 31-43, respectively.

The reliability of the instruments (NIH-CPSI and IIEF-5) was assessed with Cronbach’s alpha coefficient. The internal consistencies of the NIH-CPSI and IIEF-5 were 0.83 and 0.80, respectively.

Statistical analysis

Statistical analysis was performed using SPSS 13.0 software (SPSS Inc., Chicago, United States). For the quantitative data, results are expressed as mean±SD and a two-tailed unpaired Student t-test or one-way ANOVA with post-hoc least square differences SNK test was used. Comparison of proportions was performed by the chi-square test or Kruskal-Wallis Test. And to eliminate the influence of some related factors, such as age, etc., logistic and ordinal regression were used. All statistical analyses were two-sided, and a P value <0.05 was considered statistically significant.

Results

All the patients and individuals in the control group completed the questionnaires. Detailed demographic information of all subjects included in the study is shown in Table 2. There were no significant differences between patients and control subjects regarding age, BMI, education, duration of the relationship, or monthly income, although the PE group had a significantly higher incidence of drinking and smoking (P<0.001). Of the 438 outpatients complaining of PE, according to the criteria and classification of Waldinger et al. [9], the distribution of patients complaining of LPE, APE, NVPE, and PLED were 32.6%, 22.6%, 16.7%, and 28.1%, respectively.

Table 2.

The general characteristics of the male subjects according to the presence of premature ejaculation (PE) complaints

	With PE (N=438)	Without PE (N=493)	t/χ2	P*
Age, years	35.9±7.1	36.6±8.8	1.325	0.185
BMI, kg/m2	23.2±2.9	23.1±2.6	1.289	0.198
Smoking			13.375	<0.001
Yes	276 (63.0%)	241 (48.9%)
No	162 (37.0%)	252 (51.1%)
Drinking			21.264	<0.001
Yes	291 (66.4%)	239 (48.5%)
No	147 (33.6%)	254 (51.5%)
Duration of the relationship, years	6.52±4.08	6.81±4.22	1.063	0.288
Educational status			4.839	0.304
Illiterate	41 (9.4%)	55 (11.2%)
Literate	43 (9.8%)	62 (12.6%)
Primary education	90 (20.5%)	85 (17.2%)
High school	157 (35.8%)	160 (32.5%)
Higher education	107 (24.4%)	131 (26.6%)
Occupational status			6.778	0.079
Student	56 (12.8%)	81 (16.4%)
Unemployed	79 (18.0%)	93 (18.9%)
Employed	226 (51.6%)	215 (43.6%)
Retired	77 (17.6%)	104 (21.1%)
Monthly income			3.466	0.177
<2000 RMB	78 (17.8%)	112 (22.7%)
2000-3000 RMB	186 (42.5%)	199 (40.4%)
>3000 RMB	174 (39.7%)	182 (36.9%)

^*Difference between men with and without the complaint of PE assessed by t-test or chi-square test, as appropriate;

PE=premature ejaculation; RMB=renminbi.

Table 3 demonstrates the prevalence of PLS in all subjects. The incidence of PLS in the patient group (27.9%) was significantly higher than the incidence in the control group (15.8%, P<0.001). The mean total NIH-CPSI score was 10.0±7.9 for participants complaining of PE and 6.0±5.4 for the control group (P<0.001). The participants with PE also had higher NIH-CPSI pain sub-scores (mean 3.5±3.8) than those in the control group (mean 2.1±2.9; P<0.001), and the PE group had worse urinary sub-scores (mean 1.9±2.5) than the control group (mean 0.6±1.2; P<0.001). Patients with PE also had higher QOL sub-scores (mean 4.6±3.6) than men without PE (mean 3.3±2.7; P<0.001). On the other hand, objects with moderate or severe symptoms (NIH-CPSI score ≥15 or ≥30) occupied a significantly higher percentage (27.9%) in the PE group than in the control group (7.1%, P<0.001).

Table 3.

The distribution of men with or without complaints of premature ejaculation (PE) according to the presence of prostatitis-like symptoms, CP and the score of NIH-CPSI

	With PE (N=438)	Without PE (N=493)	χ2/t	P*
IELT	1.8±1.5	4.6±1.9	25.013	<0.001
Prostatitis-like symptoms	140 (32.0%)	78 (15.8%)	33.700	<0.001
PLS grades#			2.442	0.120
Mild (4-7)	69 (49.4%)	47 (60.1%)
Moderate or Severe (8-21)	71 (50.6%)	31 (39.9%)
NIH-CPSI
Total score	10.0±7.9	6.0±5.4	8.960	<0.001
Pain subscore	3.5±3.8	2.1±2.9	6.118	<0.001
Urinary subscore	1.9±2.5	0.6±1.2	10.118	<0.001
QoL subscore	4.6±3.6	3.3±2.7	6.181	<0.001
NIH-CPSI score grades#			71.473	<0.001
Mild (0-14)	316 (72.1%)	458 (92.9%)
Moderate (15-30)	119 (27.2%)	35 (7.1%)
Severe (31-43)	3 (0.7%)	0 (0%)

Data are expressed as the mean±standard deviation or number (percentage), as appropriate;

^*Difference between men with and without the complaint of PE assessed by t-test, chi-square test.

^#Kruskal-Wallis test was used; PE=premature ejaculation;

NIH-CPSI=National Institutes of Health Chronic Prostatitis Symptom Index; QoL=quality of life.

There was also a significant difference among different subtypes of PE patients regarding occurrence of PLS. The occurrence of PLS in PLED (42.3%) was highest among the four subtypes (P<0.001). At the same time, patients with APE and PLED had higher total NIH-CPSI scores than other subjects, although this was not significant (P=0.055). Patients with PLED had significantly higher pain sub-scores than APE and NVPE (P<0.01), but there were no significant differences in urinary scores and QoL scores among the four subtypes. The percentages of mild, moderate, and severe symptoms among the four subtypes did not have significant differences either. The results are summarized in Table 4.

Table 4.

The comparison of four premature ejaculation (PE) syndromes according to the presence of prostatitis-like symptoms, CP and the score of NIH-CPSI

	LPE (N=143)	APE (N=99)	NVPE (N=73)	PLED (N=123)	χ2/F	P*
IELT	0.8±0.4c,d	1.1±0.5c,d	2.3±1.3a,b,d	3.3±1.7a,b,c	125.875	<0.01
Prostatitis-like symptoms	32 (22.4%)	37 (37.3%)	19 (26.1%)	52(42.3%)	14.473	<0.001
PLS grades#					4.909	0.179
Mild (4-7)	14 (43.8%)	24 (64.9%)	8 (42.1%)	23 (44.2%)
Moderate or Severe (8-21)	18 (56.2%)	13 (35.1%)	11 (57.9%)	29 (55.8%)
NIH-CPSI
Total score	8.6±8.2	10.9±7.6	9.9±8.0	10.9±7.4	2.554	0.055
Pain score	2.6±3.8d	3.7±3.8	3.2±3.6d	4.6±3.5a,c	6.451	<0.01
Urinary score	1.8±2.5	2.4±2.9	1.8±2.2	1.7±2.4	1.740	0.158
QoL score	4.2±4.0	4.8±3.3	4.9±3.6	4.7±3.3	0.886	0.448
NIH-CPSI score grades#					0.663	0.882
Mild (0-14)	106 (74.1%)	71 (71.7%)	53 (72.6%)	86 (69.9%)
Moderate (15-30)	36 (25.2%)	28 (28.3%)	20 (27.4%)	35 (28.5%)
Severe (31-43)	1 (0.7%)	0 (0%)	0 (0%)	2 (1.6%)

Data are expressed as the mean±standard deviation or number (percentage), as appropriate;

^*Difference among four PE syndromes assessed by one-way ANOVA, chi-square test or Kruskal-Wallis test as appropriate.

^#Kruskal-Wallis test was used to assess the grades of prostatitis-like symptoms and NIH-CPSI score.

a, b, c, d: the result of Post-Hoc SNK test.

^aSignificant difference compared to LPE.

^bSignificant difference compared to APE.

^cSignificant difference compared to NVPE.

^dSignificant difference compared to PLED.

LPE=lifelong PE; APE=acquired PE; NVPE=natural variable PE; PLED=premature-like ejaculatory dysfunction; NIH-CPSI=National Institutes of Health Chronic Prostatitis Symptom Index; QoL=quality of life.

By the multiple logistic and ordinal regression model, we found that among age, BMI, smoking, drinking, and PE, only PE influenced the incidence of PLS (OR=0.757; IC 95%=0.676-0.848), as well as the severity of NIH-CPSI score (OR=5.355; IC 95%=1.267-2.090, all P<0.001).

Discussion

In this study, we found that there was a higher prevalence PLS (32.0%) in patients complaining of PE compared with the control group (15.8%). Additionally, the NIH-CPSI score was 10.0±7.9 in the PE group, which was higher than the control group (6.0±5.4). Therefore, patients with PLED had the highest prevalence of PLS (42.3%) and shared the highest NIH-CPSI scores with APE. In addition, patients with PE had a higher incidence of smoking and drinking than men without PE, which may be in accordance with the fact that men with unhealthy lifestyles are significantly more likely to experience sexual dysfunction [15].

The problem of correlation between PE and CP has been gaining interest for many years. A number of previous studies indicated that there was a higher prevalence of CP in patients with PE and there was a higher incidence of PE in patients with CP as well. Screponi et al. first reported that CP was related to PE. According to their study, men with LPE and APE had a higher incidence of CP, and prostatic inflammation was found in 56.5% and chronic bacterial prostatitis in 47.8% of the subjects with PE, and these novel findings were statistically significant compared with subjects without PE [6]. Liang et al. investigated 12743 men in China and reported that 36.9% had PE in the CP group, which was significantly higher than that in the whole eligible population (15.3%) [2]. Rany Shamloul et al. examined 153 men with PE and another 100 male healthy subjects, and reported that CP was found in 52% of the patients with PE, which had a significantly higher prevalence than the control group [16]. Gonen et al. studied 66 patients with chronic pelvic pain syndrome in Turkey and found that the rate of PE was higher in patients in the study group than it was in subjects without PE, and this difference was statistically significant [17]. Sönmez et al reported a higher prevalence of PE in the CP/CPPS group (67.44%) than in individuals without PE (10%) [18]. In this study, we found that the prevalence of CP was 27.9% and PLS was 32.0% in patients complaining of PE, which was lower than the above-mentioned reports. We doubt that genetically different populations and different environments would have an effect on our study. On the other hand, some subjects were afflicted by diseases of the prostate and urogenital pain instead of prostatitis.

Our study demonstrates that CP may be a cause of PE, although the underlying mechanism is still unclear. Metz et al. thought that prostatitis could fester in a mild form for years without obvious or clear symptoms except for PE [19]. Further, previous studies indicated that prostatitis treatment played a useful role in the improvement of PE [20,21]. Sensory impairment occurring before orgasm is considered one of the pathogenetic mechanisms of PE. Prostatitis may contribute to this concept by altering the sensation and modulating the ejaculatory reflex [16]. Additionally, individuals with CP that are described as busy and nervous, frequently experience depression and anxiety, and tend to have a meticulous attitude [22], which is a risk factor for PE. On the other hand, El-Nashaar et al. also reported that antibiotic treatment in patients with PE and chronic prostatitis may lead to marked improvement in IELT and ejaculatory control [23].

For PE, the new classification scheme provides a better perspective of the epidemiology, pathophysiology, etiology, and treatment of various forms of PE. In our study, prevalence rates of PE syndromes were 32.6% for LPE, 22.6% for APE, 16.7% for NVPE, and 28.1% for PLED, which was near the distribution in the study of Zhang et al. in China (35.66% for LPE, 28.07% for APE, 12.73% for NVPE, and 23.54% for PLED) [14]. But it differed from the distribution in the study of Serefoglu et al. in Turkey (62.5% for LPE, 16.1% for APE, 14.5% for NVPE, and 6.9% for PLED) [24]. It may be due to the difference of population and environment. Our study showed that in patients with different subtypes of PE, the prevalence of CP and PLS and the NIH-CPSI score were diverse. The PLED group had the highest occurrence of PLS followed by the APE group. And the PLED and APE groups shared the worst NIH-CPSI scores, although the difference was not significant in this study. This is in agreement with the statement that physical illness PE is distinguished by it being acquired (not lifelong) and generalized to all sexual situations [25]. For men with PLED, some of them often complained of decreasing IELT, although in a normal range and diminishing the ability to delay ejaculation which was in accord with the criteria of Waldinger et al. It maybe associate with CP or PLS to some extend. The LPE and NVPE group had higher prevalence PLS and had a higher NIH-CPSI score compared with the control group, which is probably due to the particular sexual behavior of boys. On the other hand, CP may act as a risk factor or could be the cause of the onset of PE before the beginning of sexual life, but without any clinical symptoms, at least in some subjects [26]. Bacterial inflammation may become chronic, sub-clinical, and cause permanent rapid ejaculation based on an organic condition [6].

Several limitations of the current study should be considered. Individuals in our study completed the questionnaires in the face of investigators, and so patients may have felt embarrassed when dealing with this sensitive personal problem. In particular, the NIH-CPSI and IIEF-5 interviews should be conducted without face-to-face contact, and so this method may have an influence on the accuracy of our findings. Other methods of obtaining data from these patients, such as internet-based surveys, should be considered for future studies. On the other hand, we used the NIH-CPSI to measure PLS in this study. But the NIH-CPSI was not specifically developed to diagnose CP despite the fact that the index had a significant discriminatory power and could be valuable in identifying men with PLS. And we did’t take any laboratory examinations and ultrasonography to exclude other diseases, such as benign prostatic hyperplasia (BPH) etc. to show an accurate diagnosis of CP. A further and more accurate definition of CP is needed to indicate the exact prevalence. Thirdly, all the individuals enrolled in this study had no concomitant ED (with an IIEF-5 score ≥22). A further research is necessary to elucidate the relationship among PLS, PE and ED. Fourthly, we did not collect psychological parameters about PE and PLS in this survey, and so the relationship between psychological factors and PE/PLS was not assessed. Fifthly, we have chosen the control group from our medical examination center, a community-based investigation should be made in the further study for more accurate study.

Conclusions

Our study showed a higher prevalence of PLS, and a higher NIH-CPSI score in patients with PE. At the same time, patients with PLED had the highest incidence of PLS. Examination of the prostate, and treatment of CP should be considered during assessment of patients with PE. On the other hand, the level of PE can also be a signal of efficacy of treatment of CP. Further research is needed to examine the relationship between CP and PE as well as the underlying mechanism, and to detect the effect of treatment of CP in delaying ejaculation time in patients with PE and CP.

Disclosure of conflict of interest

None.