Are urge incontinence and aging risk factors of erectile dysfunction in patients with male lower urinary tract symptoms?

Abstract

Introduction: Several studies have indicated that erectile dysfunction (ED) patients also suffer from lower urinary tract symptoms (LUTS). We investigated a group of men with LUTS and assessed their sexual function with the aim of being able to predict ED risk factors and introduce ED treatments earlier for this patient group.

Methods: International Prostate Symptom Score (IPSS), Overactive Bladder Symptoms Score (OABSS) and Sexual Health Inventory for Men (SHIM) score were obtained from 236 men with LUTS at their first out-patients visit. Clinical parameters such as body mass index, prostate volume, residual urine volume and prostate specific antigen were also evaluated. The relationship between the SHIM score and other clinical data was analyzed.

Results: According to the SHIM score, ED in men with LUTS was severe 15%, moderate 19%, moderate to mild 28%, mild 17%, normal 7% and data was incomplete in 14%. Based on the results of a multivariate analysis, aging (p < 0.001) and OAB severity (p = 0.024) were significantly correlated to severe and moderate ED. Furthermore, among OAB symptoms score items, urge urinary incontinence was a risk factor for severe and moderate ED (p = 0.005).

Conclusion: Aging and OAB (notably urinary urge incontinence) are risk factors for severe and moderate ED in men with LUTS.

• Aging
• erectile dysfunction
• male lower urinary tract symptoms
• overactive bladder
• urge incontinence

Introduction

Patients with erectile dysfunction (ED) and late onset hypogonadism (LOH) often suffer from male lower urinary tract symptoms (LUTS) simultaneously [1–2]. Treatment with phosphodiesterase type 5 (PDE 5) inhibitors and testosterone replacement is reported to be effective in alleviating male LUTS in these patients [2–4]. Our study investigated the existence of male LUTS in ED and LOH patients.

LUTS is a very common in elderly men [5–7], and there is a well-established relationship between LUTS and increased BMI and low testosterone [7]. However, some men with LUTS, and especially those in Japan, are hesitant to complain about any sexual dysfunctions. In patients with LUTS, the detection of ED at an earlier stage may allow a successful treatment regime and therefore improves the patient’s well-being.

Aim

To identify the risk factors for ED in male patients with LUTS.

Methods

Two hundred and thirty-six men who attended our outpatient clinic for evaluation of LUTS between April 2011 and March 2013 were assessed. At their first visit they were evaluated by history, physical examination, clinical parameters and questionnaires prior to any treatment for LUTS. The patients in this study had never been administered any LUTS medications, such as alpha-1 blockers, OAB agents, 5 alpha reductase inhibitors or PDE5 inhibitors. Consent was collected from all participants and the study was approved by the institutional ethics committee. The Clinical parameters included body mass index (BMI), prostate volume, residual urine volume and prostate specific antigen (PSA). The patients with prostate cancer, urinary tract infection and neurogenic bladder were excluded from this study.

BMI was calculated as body weight (kg) / height (m)². Degree of obesity was defined based on the BMI: underweight < 18.5, normal 18.5 – 24.9, overweight 25 – 29.9, and obese ≥30.

Total prostate volume, prostate adenoma volume and residual urine volume were evaluated by trans-rectal and/or trans-abdominal ultrasonography (prosoundalpha 7 ^R, Hitachi Aloka Medical, Mitaka, Tokyo Japan).

Serum PSA levels were measured using Lumipulse Presto^R PSA (Fujirebio, Tokyo, Japan). The normal range is <4.0 ng / mL.

The International Prostate Symptom Score (IPSS), Over Active Bladder Symptoms Score (OABSS) and Sexual Health Inventory for Men (SHIM) was also obtained. We then compared the results obtained from the questionnaires with the clinical data.

Main outcome measures

To investigate ED risk factors for male LUTS, the relationship between SHIM score and the other clinical data was evaluated. The data and statistical significance were analyzed using SPSS Statistics for Windows, version 22.0 (IBM, Armonk, NY). P < 0.05 indicated statistical significance.

Results

Two hundred and thirty-six men who consecutively presented at the outpatient clinic with LUTS were included in the study. They had a mean age of 69.6 (range 41–88; SD 8.7) years. The distribution of patients with respect to decade of life was 40–49 years 2%; 50–59 years 11%; 60–69 years 36%; 70–79 years 39%; and 80–89 years 12%. Seventy-five percent of the patients were between 60–79 years.

The IPSS in patients indicated mild symptoms 17%, moderate symptoms 54% and severe symptoms in 29%. The quality of life (QOL) index demonstrated mild symptoms 4%, moderate symptoms 46% and severe symptoms in 50%. There was incomplete data from the QOL index in five patients (Figure 1).

Figure 1. Severity of international prostate symptom score (IPSS) and quality of life (QOL) index in 236 men with LUTS. Mean ± standard deviation of IPSS and QOL index were 15.4 ± 7.3 and 4.3 ± 1.3, respectively. There was incomplete data from the QOL index in five patients.

The OABSS revealed mild symptoms 54%, moderate symptoms 40% and severe symptoms in 6% (Figure 2).

Figure 2. Overactive bladder symptoms score in 236 men with LUTS.

Severity scores of ED based on the SHIM in men with LUTS were severe 15%, moderate 19%, moderate to mild 28%, mild 17%, normal 7% and incomplete data in 14% (Figure 3).

Figure 3. Erectile dysfunction severity based on sexual health inventory for men score in 236 men with LUTS.

BMI data showed 5% of the men were underweight (BMI < 18.5), 68% were normal (BMI 18.5 – 24.9), 22% were overweight (BMI 25 – 29.9) and 5% were obese (BMI ≥ 30).

Total prostate volume and prostate adenoma volume evaluated by ultrasonography was 26.5 ± 16.0 (7.0 – 121.0) mL and 11.1 ± 10.0 (1.2 – 92.0) mL, respectively. Total prostate volumes were less than 50.0 mL in 92% of subjects.

Residual urine volume was 31.1 ± 48.5 (0.0 – 225.4) mL and 14% of patients had more than 50.0 mL residual urine volume.

Mean PSA level was 3.7 ± 6.8 (0.13 – 67.4) ng/mL. Patients with high serum PSA levels were referred for further examination and those who were diagnosed with prostate cancer were subsequently excluded from this study.

Univariate analysis (logistic regression analysis) of the relationship between SHIM score and the clinical data of men suggested that age and storage symptoms in IPSS and the OABSS were considered to be severe and moderate ED risk factors (Table 1). Furthermore, multivariate analysis with logistic regression analysis showed that age (p < 0.001) and overactive bladder (OAB) (p = 0.024) were considered to be significant risk factors for severe and moderate ED (Table 2). In addition, in a multivariate sub-analysis of data for the four OABSS items, age (p < 0.001) and urge urinary incontinence (p = 0.005) were risk factors for severe and moderate ED according to the SHIM score (Table 3).

Table 1. Risk factors for a moderate to severe score of ED (SHIM in a univariate analysis).

	Odds ratio	95% confidence interval	p value
Age	1.100	1.061 – 1.142	< 0.001
Prostate volume	0.998	0.981 – 1.015	0.809
PSA	1.001	0.961 – 1.042	0.976
Post voiding symptom	1.119	0.951 – 1.316	0.175
Storage symptoms	1.151	1.058 – 1.251	0.001
Voiding symptoms	0.996	0.934 – 1.063	0.914
QOL index	1.101	0.891 – 1.362	0.372
OABSS	1.175	1.069 – 1.290	< 0.001

ED = Erectile Dysfunction; OABSS = Overactive Bladder Symptoms Score; PSA = Prostate Specific Antigen; QOL = Quality Of Life; SHIM = Sexual Health Inventory for Men.

Table 2. Risk factors for a moderate to severe score of ED (SHIM in a multivariate analysis).

	Odds ratio	95% confidence interval	p value
Age	1.091	1.051 – 1.132	< 0.001
OABSS	1.121	1.015 – 1.238	0.024

ED = Erectile Dysfunction; OABSS = Overactive Bladder Symptoms Score; SHIM = Sexual Health Inventory for Men.

Table 3. Risk factors for a moderate to severe score of ED (SHIM in OABSS items in a multivariate analysis).

	Odds ratio	95% confidence interval	p value
Age	1.094	1.054 – 1.136	< 0.001
Urge urinary incontinence	1.539	1.136 – 2.086	0.005

ED = Erectile Dysfunction; OABSS = Overactive Bladder Symptoms Score; SHIM = Sexual Health Inventory for Men.

Discussion

The aging male suffers from several symptoms, including physiological, psychological and sexually related symptoms that are identified as LOH symptoms [6,7]. Aging, intra-pelvic surgery, diabetes mellitus, LUTS and hypertension have been identified as risk factors for ED [1]. It has also been reported that ED and LOH patients can also suffer from male LUTS [2,4,6,7]. Furthermore, treatments for ED and LOH, including PDE 5 inhibitors and testosterone replacement can also be effective at alleviating male LUTS [2–4]. Therefore, it is crucial to investigate the relationship of male LUTS in ED and LOH patients.

Elderly men with LUTS also often suffer from ED. Their chief complaint to clinicians is urinary disturbances. However, many men with LUTS hesitate to complain about sexual dysfunction.

Several common pathological mechanisms of ED and LUTS have been reported, including a decrease of nitric oxide production, hyperactivity of Rho-A/Rho-kinase (ROCK), hyperactivity of autonomic nerves, arteriosclerosis and ischemia of intra-pelvic vessels [8,9]. The more common treatments for ED and LUTS are PDE 5 inhibitors and alpha-blockers. PDE 5 inhibitors affect urethral and bladder smooth muscle, resulting in improvement of male LUTS [10,11], and alpha-blockers may also improve ED [12,13].

There are two main aspects of male LUTS, voiding and storage symptoms. Some reports have shown a relationship between ED and voiding symptoms [2,14,15], whereas others have indicated that ED and storage symptoms are associated [16–18]. Nocturia has also been reported to influence maintenance of sexual function in elderly men with benign prostate hyperplasia [19].

The current study showed that age (p < 0.001) and OAB (p = 0.024) were significantly correlated to moderate and severe ED. Irwin et al. [20] also reported that an OAB was associated with ED. In addition, in a multivariate sub-analysis of the data for the four OABSS items, urge urinary incontinence was a risk factors of moderate and severe ED as determined by the SHIM score (p = 0.005).

Recently, the PDE5 inhibitor tadalafil has been used to improve male LUTS in benign prostate hypertrophy [3]. OAB treatment with tolterodine has also been reported to be effective on sexual and emotional quality of life in sexually active women [21]. However, the clinical efficacy of OAB treatment for ED has not been shown meaning that further investigation is required.

This present report is a transverse observational study and is limited in terms of identifying the common mechanism of ED and OAB and in examining the interaction efficacy between ED and OAB treatments. However, our data suggest that, among men with LUTS, those with OAB are at high risk for ED. Therefore, the older man who clinically presents with LUTS and urge incontinence should be evaluated for ED.

Conclusion

This questionnaire based study showed that age and OAB (especially urinary urge incontinence) are risk factors for moderate to severe ED in men with LUTS. Further studies are needed including a placebo controlled trial to confirm these findings.

Declaration of interest

The authors report no conflicts of interest. The authors alone are responsible for the content and writing of this article.