Correlations between Personality Traits, Patient-Reported Outcome, and Chronic Prostatitis Symptoms in Men with Different Premature Ejaculation Syndromes

Although the personality traits (PT), patient-reported outcome (PRO), and chronic prostatitis (CP) symptoms in premature ejaculation (PE) have been evaluated, there was no study to assess their correlations in men with different PE syndromes. The purpose of this study was to assess the correlations between the PT, PRO, and CP symptoms in men with different PE syndromes. Between January 2019 and January 2021, a cross-sectional field study was conducted in our andrology clinic. Men with the complaints of PE were divided into lifelong PE (LPE), acquired PE (APE), variable PE (VPE), and subjective PE (SPE). All subjects were required to complete a verbal questionnaire with the PRO, National Institutes of Health Chronic Prostatitis Symptom Index (NIH-CPSI), and Temperament and Character Inventory (TCI-R). Finally, 479 men with the complaints of PE and 365 without the complaints of PE were enrolled. The incidence of PE syndromes in PE complaint group was as follows: LPE 16.70%, APE 48.85%, VPE 11.27%, and SPE 23.17%. Mean ages in PE complaint group were 42.53 ± 12.25 years. In the PE complaint group, the novelty seeking (NS) scores were strongest correlated with the personal distress and quality of life (QOL). The harm avoidance (HA) scores were strongest correlated with the severity of PE and pain syndromes. The self-transcendence (ST) scores were strongest correlated with the satisfaction with sexual intercourse and QOL. In addition, strongest association between the total scores of NIH-CPSI and the NS or ST scores was also found in the APE group. The HA scores were also strongest correlated with the total scores of NIH-CPSI in SPE. Strongest association between the total scores of NIH-CPSI and the NS/TI or ST/CI scores was also found in the APE group. The HA/TI scores were also strongest correlated with the total scores of NIH-CPSI in SPE.


Introduction
Premature ejaculation (PE) is one of the most common types of ejaculatory dysfunction, with a high prevalence. According to the guidelines from the International Society for Sexual medicine (ISSM) [1,2], the diagnostic criteria for PE should include three parts: (1) short intravaginal ejaculation latency time (IELT), (2) reduction in ejaculatory control, and (3) negative sexual consequences in the patient and in the partner, e.g., anxiety, depression, or decreased sexual desire.
Although these parts played the important roles in the diagnosis of PE, the definition did not cover all aspects.
For example, some men complained of PE but with the normal or extended IELTs. In addition, their decreased sexual satisfaction has affected the harmonious relationship between couples. To solve these clinical issues, Waldinger and Schweitzer have proposed a new classification of PE. Besides the lifelong PE (LPE) and acquired PE (APE), two additional PE subtypes (subjective PE (SPE) and variable PE (VPE)) have been added [3,4].
Personality was found to associate with PE [11,12]. As the internal organization of affective, emotional, cognitive, and conceptual systems, personality could determine human unique repose to the environment. Temperament and Character Inventory (TCI) scale is widely used to measure personality [13][14][15]. It has provided a comprehensive biopsychosocial model of personality and divided personality into seven dimensions that vary widely in the general population [16]. The results from our recent study have investigated the temperament-character traits (evaluated by TCI-Revised) and attitudes toward PE. We found that men with the complaints of PE reported lower novelty seeking (NS) and self-transcendence (ST) scores and higher harm avoidance (HA) than men without complaints of PE. In addition, men with VPE have shown the highest HA scores and lowest NS scores than men with other types of PE [12].
Although the personality and CP symptoms might play important roles in precipitating or maintaining PE, there was no study to assess their association in men with the complaints of PE, especially in men with four PE syndromes. Therefore, based on the new definition of PE [3,4], we investigated the above issues with the PRO, NIH-CPSI, and TCI-R.

Materials and Methods
2.1. Subjects Enrolled. Between January 2019 and January 2021, an observational and cross-sectional field study was conducted in the First Affiliated Hospital of Anhui Medical University. From the beginning of study, our team gradually established a database of all subjects. All men who have complaints of PE were enrolled from the andrology clinic of our hospital. In addition, other men with no PE complaints were enrolled from the health examination center of our hospital.
Before enrollment, the medical and sexual histories of all subjects were carefully evaluated by an andrology doctor. The inclusion criteria were as follows: (a) age of men ≥ 18 years; (b) in a heterosexual, stable, and monogamous sexual relationship with the same female partner ≥ 6 months; and (c) men can comprehend and speak Chinese. Men on medications whose ejaculatory function could be affected were excluded (e.g., selective serotonin reuptake inhibitors).

Study
Design. This study was reviewed and approved by the Anhui Medical University Research Subject Review Board. Because of some subjective questions in the study, a prestudy (n = 30) was conducted to modify the questionnaire to ensure it is comprehensive and easily understandable. In addition, subjects were informed about the survey and those who participated were asked to provide written consent.
With a face-to-face interview, all subjects were required to complete a verbal questionnaire (including demographic information (e.g., age, body mass index (BMI), lifestyle, educational and occupational status, and resident), sexual history [e.g., frequency of sexual intercourse, duration of PE complaints, and self-estimated IELT), medical history and comorbidities, the Chinese version of TCI-R, PRO measures, and NIH-CPSI). Cronbach's alpha for the TCI-R, PRO measures, and NIH-CPSI in our study were 0.79, 0.81, and 0.77, respectively.  [3,4], men with the complaints of PE were diagnosed with LPE, APE, VPE, or SPE 2.4. TCI-R. The Chinese version of TCI-R is a version of the TCI series scale which is widely used for assessing personality of adult population in China [12]. It has 240 items (each item rated on 5-level scale from completely inconsistent (score: 1) to completely in line (score: 5)) and consists of 4 dimensions of temperament-inventory (TI) (novelty seeking (NS), harm avoidance (HA), reward dependence (RD), and persistence (PS)) and 3 dimensions of character inventory (CI) (self-directedness (SD), cooperativeness (CO), and self-transcendence (ST)). The scale is suitable for people with different cultural backgrounds and has been reported good reliability and validity in our previous study [12].

Definition of PE
2.5. PRO. The Chinese version of PRO questionnaire contains five measures and has been used in our previous study [9], including control over ejaculation (response scale ranging from very poor (score 0) to very good (score 4)), satisfaction with sexual intercourse (response scale ranging from very poor (score 0) to very good (score 4)), severity of PE (response scale ranging from none (score 0) to severe (score 4)), personal distress (response scale ranging from not at all (score 0) to extremely (score 4)), and interpersonal difficulty (response scale ranging from not at all (score 0) to 2 BioMed Research International extremely (score 4)). Detailed introduction of PRO questionnaire is shown in Figure 2.
2.6. NIH-CPSI. The Chinese version of NIH-CPSI is a reliable, convenient, self-administered index. It has been widely used to assess the severity of CP syndromes in China [10,17,18]. The questionnaire of NIH-CPSI has 9 items and consists of the measures of pain symptoms (total of items 1-4), urinary symptoms (total of items 5-6), and QOL (total of items 7-9). In addition, based on the total of items 1 to 6, the severity of pain and urinary symptoms in PE complaints has also been evaluated and classified as mild (10-14 points), moderate (15-29 points), or severe (>30 points).

Statistical
Analysis. All data were analyzed by the SPSS software (SPSS Inc., Chicago, IL, USA) version 13.0. Data are expressed as mean ± standard deviation or number (percentage), as appropriate. Descriptive statistics were used to summarize the demographic information and presence of comorbidities in men with the complaints of PE and four PE syndromes. Differences between men in PE and no PE complaint groups were assessed by the dependent t-test or chi-square test, as appropriate. Differences among four PE syndromes were assessed by one-way analysis of variance or chisquare test, as appropriate. Differences between two PE syndromes were assessed by SNK-q test.
Because the ages of men with PE complaints ranged from 20 to 66 years, and PE have been found to be associated with age, correlations between the outcomes of PRO measures, NIH-CPSI, and TCI-R in the PE complaint group were assessed by partial correlations (adjusted for age). For all of the tests, P < 0:05 was deemed statistically significant.
For the total and subdomain (including pain, urinary symptoms, and QOL) scores of NIH-CPSI, their mean scores in men with PE complaint group were all significantly higher than those in men without PE complaint group (P < 0:001 for all). Mean total scores of NIH-CPSI in men with and without the complaints of PE were 23:12 ± 5:42 and 12:92 ± 3:50, respectively. Based on the classification of severity of pain and urinary symptoms, the percentage of mid, moderate, and severe of pain and urinary symptoms in PE complaint group were 37.79% (181/479), 32.99% (158/479), and 29.23% (140/479), respectively.
In addition, the NS/TI, HA/TI, and SD/ST scores in men with the complaints of PE were significantly different than those in men without the complaints of PE (P < 0:001 for

Outcomes of PRO, NIH-CPSI, and TCI-R in Men with
Four PE Syndromes. Similarly, significant differences were also found among four PE syndromes with respect to the outcomes of PRO, NIH-CPSI, and TCI-R (except for RD/ TI, PS/TI, SD/CI, and CO/CI) (severity of PE: P = 0:032; interpersonal difficulty: P = 0:024; and others: P < 0:001).
Detailed outcomes of PRO, NIH-CPSI, and TCI-R in men with four PE syndromes are shown in Table 2.
3.4. Correlations between the Outcomes of PRO, NIH-CPSI, and TCI-R in Men with the Complaints of PE. After adjusted for ages, the correlations between the outcomes of PRO, NIH-CPSI, and TCI-R in men with the complaints of PE were evaluated (Table 3).
For the outcomes of PRO, the NS/TI scores in men with the complaints of PE were strongest negatively correlated with the subdomain of personal distress (Adjust r = −0:62, P < 0:001). Their HA/TI scores were strongest positively correlated with the subdomain of severity of PE (Adjust          Furthermore, the correlations between the total scores of NIH-CPSI and NS/TI, HA/TI, or ST/CI in men with different PE syndromes were also assessed ( Table 4).

BioMed Research International
The NS/TI scores were strongest negatively correlated with the total scores of NIH-CPSI in men with APE (Adjust r = −0:70, P < 0:001). Similarly, strongest negative correlations in APE were also found between the ST/CI scores and the total scores of NIH-CPSI (Adjust r = −0:65, P < 0:001). In addition, the HA/TI scores were strongest positively correlated with the total scores of NIH-CPSI in SPE (Adjust r = 0:68, P < 0:001).

Discussion
Sexual psychology is the psychological state and processes related to sexual desire and sexual behavior on the basis of sexual physiology [19,20]. Temperament and character, as the important composition of personality, might be involved in the pathogenesis of sexual dysfunction through influencing the state of sexual psychology [11,12,[21][22][23].
From previous psychiatric researches, temperament and character were often evaluated by using TCI-R questionnaires [24][25][26]. They were derived from Cloninger's personality model and contained four dimensions about temperament and three dimensions about character. Temperament was an automated reaction of experience and often recognized as related to biological genetics. It has the characteristic of lifetime stable and moderate hereditary. In addition, character was considered to be related to environmental factors. It was gradually mature through individual learning and social experience.
PE was the most common males' sexual dysfunction and had more complex etiology, including the internal and external factors. PE was also considered to associate with the subjective and objective factors. For example, the etiology of LPE might be associated with the sensitivity of the penile nerve, but the etiology of VPE might be related to the negative psychological burden [6,10,27].
In the past, there were few studies to assess the effects of temperament and character on PE and its associated factors. This is the first study to evaluate the effects of temperament and character on men with the complaints of PE/different PE syndromes (assessing by PRO) and their CP symptoms (assessing by NIH-CPSI). Findings from this study might play an important role in revealing the pathogenesis of PE.
The results from this study showed that men with lower scores of NS/TI reported worse personal distress in the PE complaint group. In addition, the worse severity of PE was observed when men with the complaints of PE reported higher HA/TI scores. In the meantime, the positive relationships between the ST/CI scores and sexual satisfaction were also found in PE complaint group.
Previous study confirmed the above findings. With the index of PE, strongest relationships between the NS/TI scores and distress of PE were found in men with the complaints of PE. These patients were more likely to reported worse sexual satisfaction with the decreased ST/CI scores [12]. In addition, another study conducted by Kempeneers et al. has shown that men combining generalized and lifelong PE with IELT less than 30 s reported lower sexual satisfaction and higher distress and HA/TI scores [11].
The NS/TI is defined as the activation of behavior, including the impulsive response to novel stimulation and the tendency to avoid setbacks. The HA/TI reflect the inhibition of emotion and behavior when we faced harmful stimulation. The ST/CI is a characteristic related to mental state that individuals regard subject and object as a unity and considered them to be interdependent to each other. According to the findings between temperament/character and PRO outcomes in men with PE, we speculated the following circles: Temperament and character might affect patients' psychological and behavior states. For example, patients who reported lower NS/TI and higher HA/TI scores were more likely to have negative feelings (e.g., anxiety, depression) and behaviors (e.g., avoidance of sexual intercourse and not willing to seek treatment). These negative effects would further aggravate the severity of PE and influence the sexual relationships between patients and their partners.
Chronic prostatitis, a risk factor of premature ejaculation, has a greater incidence of comorbid disease [28]. Screponi et al. found that 56.5% of patients had prostatic inflammation and 47.8% had chronic bacterial prostatitis, according to a study of premature ejaculation patients [29]. CP symptoms in men with the complaints of PE were evaluated by the NIH-CPSI, which contained three dimensions of pain, urinary symptoms, and QOL. In our study, NIH-CPSI was firstly used to assess its relationships with the personality traits (PT) in men with different PE syndromes. In the PE complaint group, findings showed that the NS/TI NIH-CPSI = National Institutes of Health Chronic Prostatitis Symptom Index; PE = premature ejaculation; TCI-R = Temperament and Character Inventory-Revised. Correlations between the outcomes of NIH-CPSI and TCI-R questionnaires were analyzed by partial correlations. 8 BioMed Research International and ST/CI often influenced the QOL scores of NIH-CPSI, and the HA/TI were more likely associated with the urinary symptoms scores of NIH-CPSI. Because the NS/TI and ST/ CI were related to the activation of behavior and mental state, respectively, lower NS/TI and ST/CI scores were associated with the decline of QOL through the decreased behavioral activity and psychological burden. Additionally, because CP symptoms and psychological factors were considered the important roles in the etiology of APE and SPE, respectively, the NS/TI and HA/TI scores were found to associate with the total scores of NIH-CPSI in APE group, and the ST/CI scores were associated with those in SPE group.
However, several limitations should be considered. First, generalizability of this study may be limited by the fact that it was conducted in a single cultural/societal background. In addition, there were few studies on the effects of temperament and character on PE in the general male population. Second, patients might feel obliged to give socially acceptable answers when they answered some private, sensitive, and subjective questions with the face-to-face interview.

Conclusion
This is the first study to evaluate the correlations between PT (assessing by TCI-R) and PRO or CP symptoms (assessing by NIH-CPSI) in men with different PE syndromes in China.
In the PE complaint group, the NS/TI scores were strongest correlated with the personal distress and QOL. The HA/TI scores were strongest correlated with the severity of PE and urinary syndromes. The ST/CI scores were strongest correlated with the satisfaction with sexual intercourse and QOL. Strongest association between the total scores of NIH-CPSI and the NS/TI or ST/CI scores was also found in the APE group. The HA/TI scores were also strongest correlated with the total scores of NIH-CPSI in SPE.
Above the preliminary conclusions, further researches were needed to confirm. In addition, as an early classification method, the four types of PE has certain limitations and should be improved in the later research.

Data Availability
The data used to support the findings of this study are included within the article.