Underactive Bladder: Clinical Features, Urodynamic Parameters, and Treatment

Is detrusor underactivity the urodynamic characteristic of long-COVID in patients with benign prostate hyperplasia?

Although coronavirus disease 19 (COVID-19) was reported to involve with multiple organs, COVID-19 reports focusing on urinary system mostly evaluated the association between lower urinary tract symptoms and COVID-19 using questionnaire score. In this study, sonography video urodynamic studies was first conducted to explore the effects of COVID-19 on contractility of bladder detrusor of patients with benign prostate hyperplasia (BPH). Clinical data was respectively reviewed and compared between BPH patients with previous COVID-19 infection (COVID-19 group) and without previous COVID-19 (non-COVID-19 group). The incidence of detrusor underactivity (DU) was compared between 2 groups. Comparison of age and noninvasive parameters was conducted between BPH patients with DU and without DU in COVID-19 group. Correlation coefficient between noninvasive parameters and detrusor contractility was determined and receiver operating characteristic curve of noninvasive parameters was used to choose the most appropriate cutoff for detection of DU in COVID-19 group. Beside a significant increase in the incidence of DU in BPH patients of COVID-19 group, a lower detrusor contractility and a greater bladder wall thick was detected compared to that of patients in non-COVID-19 group. Post-voiding residual urine was found to have a linear correlation with detrusor contractility in COVID-19 group. It was suggested that COVID-19 infection would further exacerbate impairment of detrusor previously resulted from bladder outlet obstruction in BPH patients. DU may be a urodynamic characteristic of long-COVID.

Clinical features and sequelae of detrusor underactivity: a study of possible cause and effect

PURPOSE

To describe the clinical presentation and urodynamic findings in detrusor underactivity (DU) patients and investigate the association between DU and straining related complications such as pelvic organ prolapse (POP), inguinal hernia, and hemorrhoids.

METHODS

We retrospectively reviewed all consecutive patients who underwent urodynamic studies (UDS) from 2012 to 2023, divided into two groups: those with evidence of DU (n = 573), and control subjects with normal voiding parameters (n = 522). Exclusion criteria were patients who lacked sufficient data, those with obstructive voiding parameters, and those who had received intravesical botulinum toxin injections within the previous nine months. Demographic information, clinical presentation, straining related complications, and UDS findings were compared between the two groups using univariate statistical analysis.

RESULTS

The male DU group had a statistically significant higher prevalence of spinal disease and previous cerebrovascular accidents, while the female DU group had a statistically significant higher prevalence of spinal disease, multiple sclerosis, diabetes, previous colorectal surgery, previous transabdominal gynecological surgery, POP surgery, and recurrent UTIs. Female DU patients had a higher prevalence of pronounced vaginal bulging symptoms, recurrent POP, inguinal hernia, and hemorrhoids. The predominant LUTS were voiding symptoms (81.2% in males and 77.9% in females), followed closely by storage symptoms (66.2% in males and 74.7% in females). The median Qmax, PdetQmax, and PVR were 6 ml/sec, 18 cmH2O, 190 ml for male DU patients, and 8 ml/sec, 11 cmH2O, and 200 ml for female DU patients, respectively.

CONCLUSION

Risk factors for DU that were identified include age, neurological diseases (spinal disease, CVA in men, MS in women), diabetes and transabdominal surgery (colorectal, gynecological) that can cause pelvic denervation in women. DU patients commonly present with both voiding and storage symptoms. There is approximately twice the risk of having POP surgery and inguinal hernia, an eight-fold risk of hemorrhoids, and a three-fold risk of recurrent UTIs for females. This is thought to be secondary to increased intra-abdominal pressure during urinary straining.

Recent advances in soft, implantable electronics for dynamic organs

Unlike conventional rigid counterparts, soft and stretchable electronics forms crack- or defect-free conformal interfaces with biological tissues, enabling precise and reliable interventions in diagnosis and treatment of human diseases. Intrinsically soft and elastic materials, and device designs of innovative configurations and structures leads to the emergence of such features, particularly, the mechanical compliance provides seamless integration into continuous movements and deformations of dynamic organs such as the bladder and heart, without disrupting natural physiological functions. This review introduces the development of soft, implantable electronics tailored for dynamic organs, covering various materials, mechanical design strategies, and representative applications for the bladder and heart, and concludes with insights into future directions toward clinically relevant tools.

Systematic review and meta-analysis of urinary incontinence prevalence and population estimates

INTRODUCTION

Incontinence impacts the quality-of-life of people suffering from the disease. However, there is limited information on the prevalence of incontinence due to the stigma, lack of awareness, and underdiagnosis.

OBJECTIVE

This study aims to conduct a systematic review and meta-analysis of overactive bladder (OAB) and nonobstructive urinary retention (NOUR).

METHODS

The authors conducted a systematic review following the PRISMA guidelines using Embase, MEDLINE, and PubMed databases to identify the relevant publications in the English language. Two reviewers independently assessed the articles and extracted the data. Review papers were assessed for content and references. A meta-analysis of proportions was conducted using the RStudio software. To address the age heterogeneity, a subanalysis was conducted. Pooled data were overlayed on the Canadian population and a sample of 10 populous countries to estimate the number of people suffering from incontinence.

RESULTS

Twenty-eight and eight articles were selected for OAB and NOUR, respectively. The pooled prevalence of OAB in men and women was 12% (95% CI: 9%-16%) and 15% (95% CI: 12%-18%), respectively. The estimated prevalence of NOUR was 15.6%-26.1% of men over 60 and 9.3%-20% of women over 60. The subanalysis pooled prevalence of OAB in men and women was 11% (95% CI: 8%-15%) and 12% (95% CI: 9%-16%), respectively. We estimated that 1.4-2.5 million women and 1.3-2.2 million men suffer from OAB in Canada.

CONCLUSION

Urinary incontinence is an under-reported and underdiagnosed prevalent condition that requires appropriate treatment to improve a patient's quality-of-life.

Underactive Bladder and Detrusor Underactivity: New Advances and Prospectives

Underactive bladder (UAB) is a prevalent but under-researched lower urinary tract symptom that typically occurs alongside detrusor underactivity (DU). Unlike UAB, DU is a urodynamic diagnosis which the International Continence Society (ICS) defines as "a contraction of reduced strength and/or duration, resulting in prolonged bladder emptying and/or a failure to achieve complete bladder emptying within a normal time span". Despite the widespread prevalence of UAB/DU, there are significant gaps in our understanding of its pathophysiological mechanisms, diagnosis, and treatment compared with overactive bladder (OAB) and detrusor overactivity (DO). These gaps are such that clinicians regard UAB/DU as an incurable condition. In recent years, the understanding of UAB has increased. The definition of UAB has been clarified, and the diagnostic criteria for DU have been considered more comprehensively. Meanwhile, a number of non-invasive diagnostic methods have also been reported. Clinical trials involving novel drugs, electrical stimulation, and stem cell therapy have shown promising results. Therefore, this review summarizes recent reports on UAB and DU and highlights the latest advances in their diagnosis and treatment.

Wireless, Fully Implantable and Expandable Electronic System for Bidirectional Electrical Neuromodulation of the Urinary Bladder

Current standard clinical options for patients with detrusor underactivity (DUA) or underactive bladder─the inability to release urine naturally─include the use of medications, voiding techniques, and intermittent catheterization, for which the patient inserts a tube directly into the urethra to eliminate urine. Although those are life-saving techniques, there are still unfavorable side effects, including urinary tract infection (UTI), urethritis, irritation, and discomfort. Here, we report a wireless, fully implantable, and expandable electronic complex that enables elaborate management of abnormal bladder function via seamless integrations with the urinary bladder. Such electronics can not only record multiple physiological parameters simultaneously but also provide direct electrical stimulation based on a feedback control system. Uniform distribution of multiple stimulation electrodes via mesh-type geometry realizes low-impedance characteristics, which improves voiding/urination efficiency at the desired times. In vivo evaluations using live, free-moving animal models demonstrate system-level functionality.

Urodynamic findings in patients with nocturia and their associations with patient characteristics

INTRODUCTION

This study identified associations between lower urinary tract pathology confirmed on urodynamic testing, baseline characteristics, and symptoms for adults with nocturia. Nocturia frequency was examined for predictors.

METHODS

This retrospective study from 2012-2019 analyzed adult patients with nocturia (waking to void ≥2x/night) referred for urodynamic testing (UDS). Data on baseline characteristics, symptoms, UDS parameters, and lower urinary tract pathology were recorded. Males and females were analyzed separately, and univariable analyses were conducted, stratified by lower urinary tract pathology. Multivariable regression models were fit. Nocturia frequency was analyzed for associations with clinical parameters.

RESULTS

Altogether, 372 patients were included (159 men and 213 women). More men had detrusor overactivity (DO) (p<0.001) and bladder outlet obstruction (BOO) (p<0.001). DO was associated with storage symptoms (odds ratio [OR] 5.19, p<0.001), in addition to older age (p=0.009) and being male (p<0.001). Detrusor under-activity (DU) was associated with voiding symptoms (OR 1.92, p=0.004), older age (p<0.001), and being female (p=0.018). BOO was associated voiding symptoms (OR 2.09, p=0.023), younger age (p=0.018), and being male (p<0.001). The quantity of lower urinary tract symptoms was associated with DU and DO. Nocturia frequency was not associated with baseline variables or underlying pathologies. A substantial number of patients were diagnosed with DU alone (n=69, 18.7%) or associated with other diagnoses (n=108, 29.3%).

CONCLUSIONS

Careful assessment of risk factors and symptoms may help identify underlying lower urinary tract pathology for adults with nocturia. DU is found in a significant proportion of patients with nocturia, a previously under-reported result.

Magnetic soft robotic bladder for assisted urination

The poor contractility of the detrusor muscle in underactive bladders (UABs) fails to increase the pressure inside the UAB, leading to strenuous and incomplete urination. However, existing therapeutic strategies by modulating/repairing detrusor muscles, e.g., neurostimulation and regenerative medicine, still have low efficacy and/or adverse effects. Here, we present an implantable magnetic soft robotic bladder (MRB) that can directly apply mechanical compression to the UAB to assist urination. Composed of a biocompatible elastomer composite with optimized magnetic domains, the MRB enables on-demand contraction of the UAB when actuated by magnetic fields. A representative MRB for a UAB in a porcine model is demonstrated, and MRB-assisted urination is validated by in situ computed tomography imaging after 14-day implantation. The urodynamic tests show a series of successful urination with a high pressure increase and fast urine flow. Our work paves the way for developing MRB to assist urination for humans with UABs.

3D Bioprinting of an In Vitro Model of a Biomimetic Urinary Bladder with a Contract-Release System

The development of curative therapy for bladder dysfunction is usually hampered owing to the lack of reliable ex vivo human models that can mimic the complexity of the human bladder. To overcome this issue, 3D in vitro model systems offering unique opportunities to engineer realistic human tissues/organs have been developed. However, existing in vitro models still cannot entirely reflect the key structural and physiological characteristics of the native human bladder. In this study, we propose an in vitro model of the urinary bladder that can create 3D biomimetic tissue structures and dynamic microenvironments to replicate the smooth muscle functions of an actual human urinary bladder. In other words, the proposed biomimetic model system, developed using a 3D bioprinting approach, can recreate the physiological motion of the urinary bladder by incorporating decellularized extracellular matrix from the bladder tissue and introducing cyclic mechanical stimuli. The results showed that the developed bladder tissue models exhibited high cell viability and proliferation rate and promoted myogenic differentiation potential given dynamic mechanical cues. We envision the developed in vitro bladder mimicry model can serve as a research platform for fundamental studies on human disease modeling and pharmaceutical testing.

Therapeutic outcome of active management in male patients with detrusor underactivity based on clinical diagnosis and videourodynamic classification

Detrusor underactivity (DU) could be resulted from many different etiologies. Patients with DU might have reduced bladder sensation, low detrusor contractility, and large post-void residual volume. This study analyzed therapeutic outcome of active management for male DU patients, based on clinical and urodynamic characteristics. Male DU patients aged > 18 years old were retrospectively reviewed from the videourodynamic study (VUDS) records in recent 10 years. The patients’ demographics, VUDS results, treatment modalities, and treatment outcome were analyzed. The treatment outcomes were compared among patients with different DU subgroups, clinical diagnosis and treatment modalities. Patients with voiding efficiency of > 66.7% were considered having a successful treatment outcome. For comparison, 30 men with normal VUDS finding served as the control arm. Most of the DU patients had reduced bladder sensation. The reduced bladder sensation is closely associated with low detrusor contractility. After active treatment, a successful outcome was achieved in 68.4% of patients after bladder outlet surgery, 59.1% after urethral botulinum toxin A injection, and 57.6% after medical treatment, but only 18.2% after conservative treatment. A successful treatment outcome was achieved in patients with an intact detrusor contractility, either low (69.2%) or normal voiding pressure (81.8%), and in patients with a normal or increased bladder sensation (78.1%). However, patients with detrusor acontractile (41.3%) or absent bladder sensation (17.9%) had less favorable treatment outcome after any kind of urological management. This study revealed that active management can effectively improve voiding efficiency in patients with DU. The normal bladder sensation, presence of adequate detrusor contractility, and bladder outlet narrowing during VUDS provide effective treatment strategy for DU patients. Among all management, BOO surgery provides the best treatment outcome.

Defining Voiding Dysfunction in Women: Bladder Outflow Obstruction versus Detrusor Underactivity

Purpose

We aimed to develop urodynamic criteria for more accurate diagnosis of bladder outlet obstruction (BOO) and detrusor underactivity (DU) in women with lower urinary tract symptoms (LUTS).

Methods

Initially, in a group of 68 consecutive women with LUTS and increased post-void residual who had undergone urodynamic investigation we examined the level of agreement between operating physician's diagnosis of BOO or DU and diagnosis according to urodynamic nomograms/indices, including the Blaivas-Groutz (B-G) nomogram, Urethral Resistance Association (URA), Bladder Outlet Obstruction Index (BOOI) and Bladder Contractility Index (BCI). Based on the initial results, we categorized 160 women into four groups using B-G nomogram and URA (Group 1: severe-moderate BOO, Group 2: mild BOO and URA≥20, Group 3: mild BOO and URA<20 and Group 4: non-obstructed) and compared urodynamic parameters. Finally, we redefined women as obstructed (group 1+2) and non-obstructed (group 3+4) for sub-analysis.

Results

The agreement between B-G nomogram and physician's diagnosis was poor in the mild obstruction zone (kappa=0.308, p=0.01). Adding URA (cutoff value 20), an excellent level of agreement was reached (kappa=0.856, p<0.001). Statistically significant differences were found between the four groups (ANOVA) in maximum flow (Qmax) (p<0.0001), voided volume (VV) (p=0.042), post void residual (PVR) (p=0.032), BOOI (p<0.0001) and BCI (p<0.0001) with a positive linear trend for Qmax and VV and negative linear trend for PVR and BOOI from group 1 to 4. In the subanalysis all parameters were statistically different between obstructed and nonobstructive women except BCI (Qmax: p=0.0001, VV: p=0.0091, PVR: p=0.0005, BOOI: p=0.0001).

Conclusions

The combination of B-G nomogram with the URA parameter increases the accuracy of diagnosing BOO among women with LUTS. Based on this combination, most women in the mild obstruction zone of the B-G nomogram would be considered underactive rather than obstructed.

Transient receptor potential channels in sensory mechanisms of the lower urinary tract

Disruptions to sensory pathways in the lower urinary tract commonly occur and can give rise to lower urinary tract symptoms (LUTS). The unmet clinical need for treatment of LUTS has stimulated research into the molecular mechanisms that underlie neuronal control of the bladder and transient receptor potential (TRP) channels have emerged as key regulators of the sensory processes that regulate bladder function. TRP channels function as molecular sensors in urothelial cells and afferent nerve fibres and can be considered the origin of bladder sensations. TRP channels in the lower urinary tract contribute to the generation of normal and abnormal bladder sensations through a variety of mechanisms, and have demonstrated potential as targets for the treatment of LUTS in functional disorders of the lower urinary tract.

Is Nocturia Associated With Detrusor Underactivity?

OBJECTIVES

Detrusor underactivity (DU) is diagnosed using urodynamic testing. We hypothesized that nocturia is associated with detrusor underactivity.

METHODS

We performed a retrospective chart review of all women who underwent urodynamic testing at our institution between 2016 and 2018. Uroflowmetry and pressure-flow study parameters were compared between women with nocturia (≥2 voids/night) and without nocturia (0-1 void/night). Detrusor underactivity was diagnosed using 3 different criteria: (1) bladder voiding efficiency (BVE) of <90%, (2) bladder contractility index of <100, and (3) a composite of three urodynamic measures (Gammie criteria).

RESULTS

Of 358 women, 172 (48%) were in the nocturia group and 186 (52%) were in the no nocturia group. On uroflowmetry, median postvoid residual volume was similar (20 mL) in both groups. Median maximum flow rate (15 vs 17 mL/s, P < 0.05) and average flow rate (6 mL/s vs 7 mL/s, P < 0.05) were significantly lower in the nocturia group compared with the no nocturia group. During pressure-flow study, a significantly greater proportion of women with nocturia were unable to void around the catheter (30% vs 27%, P < 0.01). The overall rate of DU varied with the criteria used: BVE (54%), bladder contractility index (41%), and Gammie criteria (7%). The rate of DU using the BVE criteria was significantly higher in the nocturia group (63% vs 48%, P < 0.01), but no significant differences were noted using the other criteria.

CONCLUSIONS

Nocturia is associated with reduced voiding efficiency in women. The diagnosis of DU using urodynamics is challenging.

Detrusor underactivity influences the efficacy of TURP in patients with BPO

PURPOSE

To investigate the effect of detrusor underactivity on the efficacy of TURP in patients with benign prostate obstruction.

METHODS

A retrospective study of 350 patients with benign prostate obstruction who underwent TURP was carried out. Different degrees of bladder outlet obstruction were grouped by the bladder outlet obstruction index. ROC curves were used to calculate the optimal cut-off point for the bladder contractility index used to divide the DU patients into mild DU and severe DU patients. The effect of DU on the efficacy of TURP in benign prostate obstruction patients was studied by comparing the subjective and objective parameters preoperatively and 3 months postoperatively between severe DU, mild DU and non-DU benign prostate obstruction patients in two obstruction groups (20 ≤ BOOI < 40 and BOOI ≥ 40).

RESULTS

According to the ROC curve, the optimal cut-off point for the bladder contractility index was 82; thus, 69 patients were considered mild DU patients (82 ≤ BCI < 100), 67 patients were considered severe DU patients (BCI < 82), and 214 patients were considered non-DU patients (BCI ≥ 100). Both the postoperative subjective and objective parameters of the non-DU, mild DU and severe DU patients significantly improved in two obstruction groups. However, in the 20 ≤ BOOI < 40 group, the successful improvement rates for the IPSS, IPSS-S, IPSS-V, QoL and fQmax in the severe DU patients were only 38.2%, 38.2%, 44.1%, 41.2% and 38.2%, respectively.

CONCLUSION

Patients with varying degrees of benign prostate obstruction can benefit from TURP, but for patients with severe DU in the 20 ≤ BOOI < 40 group, TURP should be considered only after deliberation.

Expandable and implantable bioelectronic complex for analyzing and regulating real-time activity of the urinary bladder

Underactive bladder or detrusor underactivity (DUA), that is, not being able to micturate, has received less attention with little research and remains unknown or limited on pathological causes and treatments as opposed to overactive bladder, although the syndrome may pose a risk of urinary infections or life-threatening kidney damage. Here, we present an integrated expandable electronic and optoelectronic complex that behaves as a single body with the elastic, time-dynamic urinary bladder with substantial volume changes up to ~300%. The system configuration of the electronics validated by the theoretical model allows conformal, seamless integration onto the urinary bladder without a glue or suture, enabling precise monitoring with various electrical components for real-time status and efficient optogenetic manipulation for urination at the desired time. In vivo experiments using diabetic DUA models demonstrate the possibility for practical uses of high-fidelity electronics in clinical trials associated with the bladder and other elastic organs.

Advances in triboelectric nanogenerators for biomedical sensing

Biomedical sensors have been essential in improving healthcare outcomes over the past 30 years, though limited power source access and user wearability restraints have prevented them from taking a constant and active biomedical sensing role in our daily lives. Triboelectric nanogenerators (TENGs) have demonstrated exceptional capabilities and versatility in delivering self-powered and wear-optimized biomedical sensors, and are paving the way for a novel platform technology able to fully integrate into the developing 5G/Internet-of-Things ecosystem. This novel paradigm of TENG-based biomedical sensors aspires to provide ubiquitous and omnipresent real-time biomedical sensing for us all. In this review, we cover the remarkable developments in TENG-based biomedical sensing which have arisen in the last octennium, focusing on both in-body and on-body biomedical sensing solutions. We begin by covering TENG as biomedical sensors in the most relevant, mortality-associated clinical fields of pneumology and cardiology, as well as other organ-related biomedical sensing abilities including ambulation. We also include an overview of ambient biomedical sensing as a field of growing interest in occupational health monitoring. Finally, we explore TENGs as power sources for third party biomedical sensors in a number of fields, and conclude our review by focusing on the future perspectives of TENG biomedical sensors, highlighting key areas of attention to fully translate TENG-based biomedical sensors into clinically and commercially viable digital and wireless consumer and health products.

The Prevalence of Detrusor Underactivity and its Symptoms Co-relation with Urodynamic Study Findings in Patients with Lower Urinary Tract Symptoms

Purpose

This study determines the prevalence and clinical presentation of detrusor underactivity (DU) and its urodynamic characteristics in adult patients with lower urinary tract symptoms (LUTS).

Patients and Methods

This retrospective study has reviewed the symptoms and urodynamic study (UDS) findings of 283 patients with LUTS. Chi-square analysis was used to present the prevalence of UDS characteristics in both sexes.

Results

Out of records of 206 patients included in this study, fifty-one (24.76%) patients were diagnosed with DU based on bladder contractility index. Storage lower urinary tract symptoms were the most prevalent characteristic presentation in both sexes as compared to the difficulty in voiding, recurrent urine retention, and urinary incontinence. Bladder outlet, sphincter EMG findings, and degree of DU were significantly correlated with gender.

Conclusion

DU is a prevalent and sophisticated bladder pathology rather than a simple one. It requires more attention from the urologists, and evaluations, including UDS, to differentiate it from other pathologies.

Sacral neuromodulation for symptomatic chronic urinary retention in females: do age and comorbidities make a difference?

OBJECTIVES

To evaluate if age and medical comorbidities are associated with progression to implantation of sacral neuromodulation devices in women with symptomatic chronic urinary retention.

METHODS

This multisite retrospective cohort included women with symptomatic chronic urinary retention who had a trial phase of sacral neuromodulation. The primary outcome was progression to implantation. Post-implantation outcomes were assessed as stable response versus decreased efficacy. A sub-analysis of catheter-reliant (intermittent-self catheterization or indwelling) patients was performed. Age was analyzed by 10-year units (decades of age). Multivariate logistic regression determined odds ratios for outcomes of implantation and for post-implantation stable response.

RESULTS

Implantation occurred in 86% (243/284) women across six academic institutions. Most patients (160/243, 66%) were catheter reliant at the time of trial phase. Increased decade of age was associated with reduced implantation in all women [OR 0.54 (95% CI 0.42, 0.70)] and in the subgroup of catheter-reliant women [OR 0.52 (95% CI 0.37, 0.73)]. Post-implantation stable response occurred in 68% (193/243) of women at median follow-up of 2 years (range 0.3-15 years). Medical comorbidities present at the time of trials did not impact progression to implantation or post-implantation success.

CONCLUSIONS

Increasing decade of age is associated with reduced implantation in women with symptomatic chronic urinary retention. There is no age cutoff at which outcomes change. Post-implantation stable response was not associated with age or medical comorbidities.

Evaluation of pre-operative bladder contractility as a predictor of improved response rate to a staged trial of sacral neuromodulation in patients with detrusor underactivity

PURPOSE

Sacral neuromodulation (SNM) is one of the few management options shown to improve outcomes in patients with detrusor underactivity (DU). This original research will investigate if preserved bladder contractility can predict a successful treatment with SNM.

METHODS

This is a retrospective study of a prospectively collected database of consecutive patients with DU, who had a staged SNM trial from January 2013 to December 2018, with a minimum of 12 months follow-up. The primary outcome was the success of stage 1 SNM trial.

RESULTS

In total, 69 patients with DU were followed. The median age was 67 [interquartile range (IQR) 74-55], median baseline bladder contractility index (BCI) 18 (IQR 67-0), and median post-void residual 200 mL (IQR 300-130). There were 35 patients (51%) that responded to a SNM trial. At a median follow-up of 23 months (IQR 39-12), three were removed for poor efficacy. In patients with detrusor acontractility (DAC), six responded (33%), compared to 29 patients (57%) with BCI > 0. This was statistically significant, p value 0.03. Younger age was also a predictive factor for SNM response, p value 0.02. There were no differences noted in those with gender, neurogenic history, previous pelvic surgery, diabetes, or pre-operative voiding history.

CONCLUSION

Our study showed that patients with preserved bladder contractility are more likely to respond to a trial of SNM compared with those that have DAC. Younger age was also predictive of SNM response. UDS is the only method to accurately identify DAC patients. This information will help in patient selection and pre-operative counselling.

Understanding underactive bladder: a review of the contemporary literature

Underactive bladder (UAB) is characterized by prolonged voiding, hesitancy, and slow and/or intermittent stream with or without a sensation of incomplete bladder emptying. The overlap of UAB lower urinary tract symptoms with those of overactive bladder or bladder outlet obstruction, as well as its multifactorial etiology, make UAB study, as well as its diagnosis and management, a very arduous and challenging task. Therefore, despite its incidence and significant impact in the quality of life of both men and women, UAB remains a poorly understood urologic condition with insufficient and ineffective treatment options available. In this review, we will focus on the etiology theories that have been proposed and the animal models available to test those theories.

Poly-phosphate increases SMC differentiation of mesenchymal stem cells on PLGA-polyurethane nanofibrous scaffold

The use of bioactive scaffolds in tissue engineering has a significant effect on the damaged tissue healing by an increase in speed and quality of the process. Herein, electrospinning was applied to fabricate composite nanofibrous scaffolds by Poly lactic-co-glycolic acid (PLGA) and Polyurethane (PU) with and without poly-phosphate (poly-P). Scaffolds were characterized morphologically by scanning electron microscope (SEM), and their biocompatibility was also investigated by SEM, protein adsorption, cell attachment and survival assays. The applicability of the scaffolds for bladder tissue engineering was also evaluated by culturing mesenchymal stem cells (MSCs) on the scaffolds and their differentiation into smooth muscle cell (SMC) was studied at the gene and protein levels. The results demonstrated that scaffold biocompatibility was increased significantly by loading poly-P. SMC related gene and protein expression level in MSCs cultured on poly-P-loaded scaffold was also increased significantly compared to those cells cultured on empty scaffold. It can be concluded that poly-P hasn’t also increased scaffold biocompatibility, but also SMC differentiation potential of MSCs was also increased while cultured on the poly-P containing scaffold compared to the empty scaffold. Taken together, our study showed that PLGA–PU–poly-P alone and in combination with MSCs has a promising potential for support urinary bladder smooth muscle tissue engineering.

[Analysis of urodynamic study of female outpatients with lower urinary tract symptoms and follow-up of the patients with detrusor underactive]

OBJECTIVE

To find out the prevalence of lower urinary tract symptoms (LUTS) and analyze the characteristics of the urodynamics diagnosis in female outpatients. To study the natural history of detrusor underactive (DU) by the followed up.

METHODS

A retrospective study of the female LUTS outpatients in Peking University People's Hospital from Jan. 2005 to Dec. 2015 was performed. The basic information and the urodynamic results of a total of 656 female outpatients were collected. The distribution of storage symptoms, voiding symptoms, complications and urodynamic diagnosis were analyzed. The symptoms and urodynamic results were compared among the groups, which were divided according to age, urodynamic diagnosis and diabetes mellitus. A follow-up of 163 female DU outpatients was performed, including the treatments and the American Urological Association symptoms scores (AUAss).

RESULTS

Frequency (25.03%) is the most common symptom in female outpatients, followed by stress urinary incontinence (20.04%), urgency (19.97%), and difficulty of voiding (17.32%). Stress urinary incontinence (SUI) accounted for the first (36.04%) of the whole outpatients, followed by the DU (24.08%), and bladder outlet obstruction (17.58%). The patients aged 51-60 years occupied the peak of almost all the diagnosis. There was a higher proportion of the young female patients than that of the middle and old patients diagnosed with no abnormal after the urodynamic study. The first, strong, urge and maximum bladder capacity were significantly larger in DU patients with diabetes than without diabetes. Follow-up results of the DU patients showed there was no significantly difference of the AUAss scores in both the two groups before and after the follow-up, but the quality of life decreased significantly.

CONCLUSION

Female LUTS outpatients showed a main complaint of storage symptoms. SUI ranked the first in female patients with LUTS. With the increase of age, bladder sensation and detrusor function decrease. In elderly patients, DU became the first ranked disease instead of SUI. Diabetes can affect the sensory function of bladder in patients with DU, and then increase the difficulty of voiding. The patients with DU, absent from treatment, experienced a lower quality of life.

[Analysis of urodynamic study of female outpatients with lower urinary tract symptoms and follow-up of the patients with detrusor underactive]

OBJECTIVE

To find out the prevalence of lower urinary tract symptoms (LUTS) and analyze the characteristics of the urodynamics diagnosis in female outpatients. To study the natural history of detrusor underactive (DU) by the followed up.

METHODS

A retrospective study of the female LUTS outpatients in Peking University People's Hospital from Jan. 2005 to Dec. 2015 was performed. The basic information and the urodynamic results of a total of 656 female outpatients were collected. The distribution of storage symptoms, voiding symptoms, complications and urodynamic diagnosis were analyzed. The symptoms and urodynamic results were compared among the groups, which were divided according to age, urodynamic diagnosis and diabetes mellitus. A follow-up of 163 female DU outpatients was performed, including the treatments and the American Urological Association symptoms scores (AUAss).

RESULTS

Frequency (25.03%) is the most common symptom in female outpatients, followed by stress urinary incontinence (20.04%), urgency (19.97%), and difficulty of voiding (17.32%). Stress urinary incontinence (SUI) accounted for the first (36.04%) of the whole outpatients, followed by the DU (24.08%), and bladder outlet obstruction (17.58%). The patients aged 51-60 years occupied the peak of almost all the diagnosis. There was a higher proportion of the young female patients than that of the middle and old patients diagnosed with no abnormal after the urodynamic study. The first, strong, urge and maximum bladder capacity were significantly larger in DU patients with diabetes than without diabetes. Follow-up results of the DU patients showed there was no significantly difference of the AUAss scores in both the two groups before and after the follow-up, but the quality of life decreased significantly.

CONCLUSION

Female LUTS outpatients showed a main complaint of storage symptoms. SUI ranked the first in female patients with LUTS. With the increase of age, bladder sensation and detrusor function decrease. In elderly patients, DU became the first ranked disease instead of SUI. Diabetes can affect the sensory function of bladder in patients with DU, and then increase the difficulty of voiding. The patients with DU, absent from treatment, experienced a lower quality of life.

Retrospective evaluation of early risk factors in children with different types of micturition disorders

AIM

The aetiology of micturition disorders in children is multifactorial and still unclear. The perinatal factors may play a role in the development of children's urinary incontinence. We compared each type of micturition disorders in terms of length of gestation, birthweight, family history of bedwetting and delivery type.

METHODS

Data were from 488 patients of the Department of Pediatrics and Nephrology, Children's Clinical Hospital of the Medical University of Bialystok, and included: age, sex, clinical diagnosis, perinatal history, constipation, history of vesicoureteral reflux, family history of nocturnal enuresis, urodynamic diagnosis, bladder capacity. We performed statistical analysis using Mann-Whitney and Spearman tests.

RESULTS

Combined daytime-nocturnal incontinence made a higher percentage and nocturnal enuresis made a lower percentage of clinical diagnoses in children with low birthweight compared with group of normal birthweight. In children with micturition disorders, lower birthweight was associated with smaller bladder capacity than normal for age.

CONCLUSION

Low birthweight might predispose to combined daytime-nocturnal incontinence. We are the first to show that patients suffering from micturition disorders with low birthweight present lower estimated bladder capacity than age-matched children. Thus, we assume that low birthweight may have strong clinical relevance in children's micturition disorders.

The development of the ICIQ-UAB: A patient reported outcome measure for underactive bladder

AIMS

To present the development of the International Consultation on Incontinence Questionnaire-underactive bladder (ICIQ-UAB) as the first patient reported outcome measure for the assessment of the symptoms and impact on the health-related quality of life of UAB developed in-line with the Food and Drug Administration Guidance for Industry.

METHODS

Draft items were developed following 44 semi-structured concept elicitation interviews in the UK and refined using 36 cognitive interviews. A pilot study was designed to assess the draft ICIQ-UAB's initial psychometric properties with 54 patients recruited from European hospitals. Further concept elicitation interviews were also carried out with 11 patients in the US and 10 patients in Japan. All participants had a prior urodynamic diagnosis of detrusor underactivity.

RESULTS

The cognitive interviews confirmed the initial items to be understood and interpreted as intended. Pilot testing showed that both internal consistency (Cronbach's α ≥ 0.85) and test-retest reliability (stable patients; intraclass correlation coefficient ≥ 0.88) were high. The interviews in the US and Japan elicited symptoms and impacts that support previous findings in the UK and provided further insight into the experiences of patients in those countries. The developmental ICIQ-UAB was refined using the evidence from all substudies.

CONCLUSIONS

The validity and reliability of the ICIQ-UAB were supported in a pilot study setting and the wider cultural applicability by the additional interviews in the US and Japan. Following further validation in future clinical trials, the developmental ICIQ-UAB is envisaged as an important tool for the monitoring of future UAB treatment strategies.

Female underactive bladder - Current status and management

Underactive bladder (UAB) is defined by the International Continence Society as a symptom complex characterized by a slow urinary stream, hesitancy, and straining to void, with or without a feeling of incomplete bladder emptying sometimes with storage symptoms. Until recently, the topic has received little attention in the literature probably due to a lack of consistent definitions and diagnostic criteria. We performed a literature review to identify articles related to the diagnosis and management of UAB, specifically in female patients. UAB is a common clinical entity, occurring in up to 45% of females depending on definitions used. Prevalence increases significantly in elderly women and women who live in long-term care facilities. The exact etiology and pathophysiology for developing UAB is unknown, though it is likely a multifactorial process with contributory neurogenic, cardiovascular, and idiopathic causes. There are currently no validated questionnaires for diagnosing or monitoring treatment for patients with UAB. Management options for females with UAB remain limited, with clean intermittent catheterization, the most commonly used. No pharmacotherapies have consistently been proven to be beneficial. Neuromodulation has had the most promising results in terms of symptom improvement, with newer technologies such as stem-cell therapy and gene therapy requiring more evidence before widespread use. Although UAB has received increased recognition and has been a focus of research in recent years, there remains a lack of diagnostic and therapeutic tools. Future research goals should include the development of targeted therapeutic interventions based on pathophysiologic mechanisms and validated diagnostic questionnaires.

Closed-loop stimulation of the pelvic nerve for optimal micturition

OBJECTIVE

Neural stimulation to restore bladder function has traditionally relied on open-loop approaches that used pre-set parameters, which do not adapt to suboptimal outcomes. The goal of this study was to examine the effectiveness of a novel closed-loop stimulation paradigm for improving micturition or bladder voiding.

APPROACH

We compared the voiding efficiency obtained with this closed-loop framework against open-loop stimulation paradigms in anesthetized rats. The bladder pressures that preceded voiding, and the minimum current amplitudes for stimulating the pelvic nerves to evoke bladder contractions, were first calibrated for each animal. An automated closed-loop system was used to initiate voiding upon bladder fullness, adapt the stimulation current by using real-time bladder pressure changes to classify voiding outcomes, and halt stimulation when the bladder had been emptied or when the safe stimulation limit was reached.

MAIN RESULTS

In vivo testing demonstrated that the closed-loop system achieved high voiding efficiency or VE (75.7%  ±  3.07%, mean  ±  standard error of the mean) and outperformed open-loop systems with either conserved number of stimulation epochs (63.2%  ±  4.90% VE) or conserved charge injected (32.0%  ±  1.70% VE). Post-hoc analyses suggest that the classification algorithm can be further improved with data from additional closed-loop experiments.

SIGNIFICANCE

This novel approach may be applied to an implantable device for treating underactive bladder (<60% VE), especially in cases where under- or over-stimulation of the nerve is a concern.

Novel Applications of OnabotulinumtoxinA in Lower Urinary Tract Dysfunction

OnabotulinumtoxinA (BoNT-A) was first used to treat neurogenic lower urinary tract dysfunction (LUTD) 30 years ago. Recently, application of BoNT-A in LUTD have become more common since the approval of intravesical BoNT-A injection for patients with both overactive bladders (OAB) and neurogenic detrusor overactivity (NDO) by regulatory agencies in many countries. Although unlicensed, BoNT-A has been recommended to treat patients with interstitial cystitis/bladder pain syndrome (IC/BPS) under different guidelines. BoNT-A delivery with liposome-encapsulation and gelation hydrogel intravesical instillation provided a potentially less invasive and more convenient form of application for patients with OAB or IC/BPS. BoNT-A injections into the urethral sphincter for spinal cord injury patients with detrusor-sphincter dyssynergia have been used for a long time. New evidence revealed that it could also be applied to patients with non-neurogenic dysfunctional voiding. Previous studies and meta-analyses suggest that BoNT-A injections for patients with benign prostate hyperplasia do not have a better therapeutic effect than placebo. However, new randomized and placebo-controlled trials revealed intraprostatic BoNT-A injection is superior to placebo in specific patients. A recent trial also showed intraprostatic BoNT-A injection could significantly reduce pain in patients with chronic prostatitis. Both careful selection of patients and prudent use of urodynamic evaluation results to confirm diagnoses are essential for successful outcomes of BoNT-A treatment for LUTD.

Outcomes of intradetrusor onabotulinum toxin A injection in patients with Parkinson's disease

OBJECTIVE

To assess the safety and efficacy of intradetrusor onabotulinum toxin A injections for the treatment of overactive bladder (OAB) in patients with Parkinson's disease (PD).

METHODS

All PD patients who underwent intradetrusor injections of onabotulinum toxin A (BoNT-A) for storage symptoms between 2010 and 2017 were included in a retrospective study. A 100 U dose of BoNT-A (Botox®, Allergan Irvine, CA) was used for the first injection in all patients. The primary endpoint was clinical success defined as any subjective improvement in OAB symptoms self-assessed by the patients 4 weeks after the injections.

RESULTS

Out of 24 patients analyzed, 19 reported improvement of their OAB symptoms 4 weeks after the first injection (79.2%) with complete resolution of urgency urinary incontinence in seven patients (29.1%; P < 0.001). The average post-void residual (PVR) increased significantly after the first injection from 17.6 to 125.3 mL (P < 0.001). Three of the patients had to start clean intermittent catheterization (CIC) after the first injection (12.5%). Out of 49 injections in total, only five caused incomplete bladder emptying requiring the use of CIC (10.2%). Higher pre-injection PVR was significantly associated with both a lower chance of symptomatic improvement (P = 0.04) and a higher risk of incomplete bladder emptying with institution of CIC (P = 0.047).

CONCLUSION

Intradetrusor injections of BoNT-A 100 U appeared as a safe and effective option in PD patients with OAB symptoms and a low PVR before the injection. Higher preoperative PVR was the strongest predictor of both treatment failure and postoperative urinary retention requiring CIC.

Toward Self-Control Systems for Neurogenic Underactive Bladder: A Triboelectric Nanogenerator Sensor Integrated with a Bistable Micro-Actuator

Aging, neurologic diseases, and diabetes are a few risk factors that may lead to underactive bladder (UAB) syndrome. Despite all of the serious consequences of UAB, current solutions, the most common being ureteric catheterization, are all accompanied by serious shortcomings. The necessity of multiple catheterizations per day for a physically able patient not only reduces the quality of life with constant discomfort and pain but also can end up causing serious complications. Here, we present a bistable actuator to empty the bladder by incorporating shape memory alloy components integrated on flexible polyvinyl chloride sheets. The introduction of two compression and restoration phases for the actuator allows for repeated actuation for a more complete voiding of the bladder. The proposed actuator exhibits one of the highest reported voiding percentages of up to 78% of the bladder volume in an anesthetized rat after only 20 s of actuation. This amount of voiding is comparable to the common catheterization method, and its one time implantation onto the bladder rectifies the drawbacks of multiple catheterizations per day. Furthermore, the scaling of the device for animal models larger than rats can be easily achieved by adjusting the number of nitinol springs. For neurogenic UAB patients with degraded nerve function as well as degenerated detrusor muscle, we integrate a flexible triboelectric nanogenerator sensor with the actuator to detect the fullness of the bladder. The sensitivity of this sensor to the filling status of the bladder shows its capability for defining a self-control system in the future that would allow autonomous micturition.

Recent advances in the understanding and management of underactive bladder

Underactive bladder (UAB) is an important and complex urological condition resulting from the urodynamic finding of detrusor underactivity. It can manifest in a wide range of lower urinary tract symptoms, from voiding to storage complaints, and can overlap with other conditions, including overactive bladder and bladder outlet obstruction. However, UAB continues to be poorly understood and inadequately researched. In this article, we review the contemporary literature pertaining to recent advances in defining, understanding, and managing UAB.

Urinary Urgency in Working Women: What Factors Are Associated with Urinary Urgency Progression?

BACKGROUND

Urinary urgency is the primary symptom of overactive bladder (OAB). This study aimed to identify targets for effective intervention to delay progression of urinary urgency.

MATERIAL AND METHODS

Secondary analyses of data from a study conducted with female employees of a large academic medical center were conducted. Women were ≥18 years and nonpregnant at the time of the survey. An online questionnaire obtained demographic information, presence of lower urinary tract symptoms, and toileting behaviors. Bivariate analyses and multivariate logistic regression were applied to explore factors related to different stages of urinary urgency.

RESULTS

Four stages of urinary urgency were constructed: (1) Stage 1: no urinary symptoms (n = 20), (2) Stage 2: continent but urinary urgency reported (n = 19), (3) Stage 3: nonsevere urgency urinary incontinence (UUI) (incontinent but leakage ≤1/day, n = 74); and (4) Stage 4: severe UUI (leakage ≥1/day, n = 26). In multivariate analyses, older women were more likely to be in Stage 3 than in Stage 2 (aOR 1.053, 95% CI 1.012-1.096). Women who lost urine with defecation were more likely to be in Stage 4 than Stage 3 (aOR 3.828, 95% CI 1.921-7.629). Women who habitually strained to empty the bladder faster were more likely to be in Stage 4 than in Stage 3 (aOR 6.588, 95% CI 1.317-32.971).

CONCLUSIONS

Losing urine with defecation and making the bladder empty faster by pushing down should be explored as intervention targets to prevent women from progressing from Stage 3 to Stage 4.

Epidemiology of underactive bladder: Common but underresearched

Detrusor underactivity (DU) or underactive bladder is a common cause of lower urinary tract symptoms (LUTS), but it is still poorly understood and underresearched. Although there has been a proposed definition by International Continence Society in 2002, no widely accepted diagnostic criteria have been established for this entity in clinical practice. Therefore, it has been rare to identify community-based researches on the epidemiology of DU until now. Only certain studies have reported the prevalence of DU in community-dwelling cohorts with significant LUTS using arbitrary urodynamic criteria for DU and these investigations have indicated that DU accounts for 25%–48% and 12%–24% of elderly men and women, respectively. However, these prevalence data based on the urodynamic definition apparently are limited in their extrapolation to the general population. Despite the clinical ambiguity of DU, its clinical effects on quality of life are quite significant, especially in the elderly population. An overall and proper comprehension of epidemiologic studies of DU may be crucial for better insight into DU, relevant decision making, and a more reasonable allocation of health resources. Therefore, researchers should find clues to the solution for the clinical diagnosis of this specific condition of LUTS from contemporary epidemiologic studies and try to develop a possible definition of ‘clinical’ DU from further studies.

Definition and symptoms of underactive bladder

Underactive bladder (UAB) is a symptom syndrome reflecting the urodynamic observation of detrusor underactivity (DU), a voiding contraction of reduced strength and/or duration, leading to prolonged or incomplete bladder emptying. An International Continence Society Working Group has described UAB as characterised by a slow urinary stream, hesitancy and straining to void, with or without a feeling of incomplete bladder emptying and dribbling, often with storage symptoms. Since DU often coexists with bladder outlet obstruction, or storage dysfunction (detrusor overactivity or incontinence), the exact contribution of the DU to the presenting complaints can be difficult to establish. The presence of voiding and post voiding lower urinary tract symptoms (LUTS) is implicitly expected in UAB, but a reduced sensation of fullness is reported by some patients, and storage LUTS are also an important factor in many affected patients. These may result from a postvoid residual, but often they do not. The storage LUTS are often the key driver in leading the patient to seek healthcare input. Nocturia is particularly common and bothersome, but what the role of DU is in all the range of influences on nocturia has not been established. Qualitative research has established a broad impact on everyday life as a result of these symptoms. In general, people appear to manage the voiding LUTS relatively well, but the storage LUTS may be problematic.

The underactive bladder: diagnosis and surgical treatment options

The underactive bladder (UAB)/detrusor underactivity (DU) is a relatively common condition. It is difficult to diagnose and can be difficult to manage. The aim of this review is to provide a review of the diagnosis and different surgical treatment options for UAB/DU. A comprehensive literature review using medical search engines was performed. The search included a combination of the following terms, UAB, DU, TURP, reduction cystoplasty, bladder diverticulectomy and sacral neuromodulation (SNM). Search results were assessed for their overall relevance to this review. Definitions, general overview and management options were extracted from the relevant medical literature. DU affects up to 45% of men and women >70 years of age. The symptoms of DU overlap significantly with overactive bladder (OAB) and bladder outlet obstruction (BOO). Urodynamic findings include low voiding pressure combined with slow intermittent flow and incomplete bladder emptying. Non-operative management for DU is acceptable; only 1 in 6 male patients may need a TURP and acute urinary retention (AUR) is rare. TURP for DU is feasible and is associated with good short and medium term outcomes, but over time, there is a return to baseline symptoms. Bladder diverticulectomy can also improve DU, but there is a paucity of guidelines on patient selection. SNM provides excellent outcomes for DU, but patient selection is important.

Impact of bladder dysfunction in the management of post radical prostatectomy stress urinary incontinence-a review

Bladder dysfunction is a relatively common urodynamic finding post radical prostatectomy (RP). It can be the sole cause of post prostatectomy incontinence (PPI) or may be found in association with stress urinary incontinence (SUI). The aim of this review is to provide a comprehensive review of the diagnosis and different treatments of post RP bladder dysfunction. A comprehensive literature review using medical search engines was performed. The search included a combination of the following terms, PPI, detrusor overactivity (DO), detrusor underactivity (DU), impaired compliance, anticholinergic, onabotulinumtoxinA (Botox^®) and sacral neuromodulation (SNM). Definitions, general overview and management options were extracted from the relevant medical literature. DO, DU and impaired compliance are common and may occur alone or in combination with SUI. In some patients the conditions exist pre RP, in others they arise due to denervation and surgical changes. DO can be treated with anticholinergics, Botox^® and SNM. DO may need to be treated before SUI surgery. DU may be a contraindication to male sling surgery as some patients may go into urinary retention. Severely impaired bladder compliance may be a contraindication to SUI surgery as the upper tracts may be at risk. Each individual dysfunction may affect the outcome of PPI treatments and clinicians should be alert to managing bladder dysfunction in PPI patients.

Changes in Adenosine Triphosphate and Nitric Oxide in the Urothelium of Patients with Benign Prostatic Hyperplasia and Detrusor Underactivity

PURPOSE

We investigated changes in the levels of adenosine triphosphate and nitric oxide in the urothelium of men with detrusor underactivity and benign prostatic hyperplasia.

MATERIALS AND METHODS

We prospectively enrolled in study 30 men who planned to undergo surgical treatment for benign prostatic hyperplasia. The 15 patients with a bladder contractility index less than 100 were assigned to the detrusor underactivity group while the 15 with a bladder contractility index more than 100 were assigned to the no detrusor underactivity group. Bladder mucosal specimens were collected at surgical prostate resection, and adenosine triphosphate and endothelial nitric oxide synthase were analyzed in these specimens. The levels of adenosine triphosphate and endothelial nitric oxide synthase were compared between the 2 groups. The correlation of urodynamic parameters with adenosine triphosphate and endothelial nitric oxide synthase was assessed in all patients.

RESULTS

Mean ± SEM endothelial nitric oxide synthase did not significantly differ between the detrusor underactivity and no underactivity groups (3.393 ± 0.969 vs 1.941 ± 0.377 IU/ml, p = 0.247). However, the mean level of adenosine triphosphate in the detrusor underactivity group was significantly lower than in the no detrusor underactivity group (1.289 ± 0.320 vs 9.262 ± 3.285 pmol, p = 0.011). In addition, in all patients adenosine triphosphate positively correlated with the bladder contractility index (r = 0.478, p = 0.018) and with detrusor pressure on maximal flow (r = 0.411, p = 0.046).

CONCLUSIONS

Adenosine triphosphate was significantly decreased in the urothelium in men with detrusor underactivity and benign prostatic hyperplasia, reflecting the change in detrusor function.

Phenotyping women with detrusor underactivity by presumed etiology: Is it plausible?

AIMS

Underactive bladder (UAB) is a symptom complex with poorly characterized causation. The aim of this study was to determine if clinical and UDS parameters differed between categories of presumed detrusor underactivity (DU) etiologies.

METHODS

A retrospective review was performed at a single institution from 2011 to 2015 to identify patients with symptoms of UAB. Patients were excluded if they were male, had anti-incontinence, or pelvic organ prolapse (POP) surgery within 1 year, or the UDS did not demonstrate DU as defined within. Subjects were stratified by etiology into four cohorts: cardiovascular disease manifestations (CV), cardiac risk factors (CVR), neurologic (N), or idiopathic (I). Patient demographics, comorbidities, symptomatology, physical exam, and UDS parameters were compared.

RESULTS

A total of 200 patients met inclusion criteria (CV: n = 53 [26.5%], CVR: n = 44 [22%] N: n = 81 [40.5%], I: n = 22 [11%]). Women in the CV cohort were significantly older and more likely to be post-menopausal (P < 0.001). There were no differences between cohorts for BMI (P = 0.48), recurrent UTI (P = 0.63), history of urinary retention (AUR) (P = 0.65), POP (0.49), American Urological Association Symptom Score (AUA-SS) (P = 0.06), presenting symptomatology [urgency, frequency, urgency urinary incontinence, AUR, incomplete emptying, hesitancy, UTI (P = 0.97)], or UDS parameters (first sensation [P = 0.25], normal desire [P = 0.80], strong desire [P = 0.58], capacity [P = 0.11], Qmax [P = 0.50], Pdet at Qmax [P = 0.22], post-void residual [P = 0.82]).

CONCLUSIONS

Though differences were observed between cohorts for age and menopausal status, clinical or urodynamic parameters did not demonstrate distinct differences across presumed categories of etiology, suggesting that the etiology of DU may be multifactorial. Neurourol. Urodynam. 36:1151-1154, 2017. © 2016 Wiley Periodicals, Inc.

Addressing challenges in underactive bladder: recommendations and insights from the Congress on Underactive Bladder (CURE-UAB)

Underactive bladder (UAB) is an expanding troublesome health issue, exerting a major influence on the health and independence of older people with a disproportionally low level of attention received. The 2nd International Congress on Underactive Bladder (CURE-UAB 2) convened in Denver, CO on December 3 and 4, 2015, and comprised of top clinicians, scientists, and other stakeholders to address the challenges in UAB. A series of workshops aimed to define UAB and its phenotype, define detrusor underactivity (DU) and create a subtyping of DU, evaluate existing animal models for DU, and lastly to establish research priorities for UAB.

Progressive changes in detrusor function and micturition patterns with chronic bladder ischemia

Purpose

Lower urinary tract symptoms (LUTS) are bothersome constellation of voiding symptoms in men and women as they age. Multiple factors and comorbidities are attributed to this problem but underlying mechanisms of nonobstructive nonneurogenic detrusor overactivity, detrusor underactivity and LUTS remain largely unknown. Our goal was to characterize detrusor function and voiding patterns in relation to muscarinic receptors expression, nerve fiber density, and neural ultrastructure in chronic bladder ischemia.

Materials and Methods

Iliac artery atherosclerosis and bladder ischemia were produced in male Sprague-Dawley rats. At 8 and 16 weeks after ischemia, micturition patterns and cystometrograms were recorded in conscious rats then bladder blood flow and nonvoiding spontaneous contractions were measured under general anesthesia. Bladder tissues were processed for Western blotting, immunostaining, and transmission electron microscopy.

Results

Bladder responses to ischemic insult depended on the duration of ischemia. Micturition patterns and cystometric changes at 8-week ischemia suggested detrusor overactivity, while voiding behavior and cystometrograms at 16-week ischemia implied abnormal detrusor function resembling underactivity. Upregulation of muscarinic M2 receptor was found after 8- and 16 weeks of ischemia. Downregulation of M3 and upregulation of M1 were detected at 16-week ischemia. Neural structural damage and marked neurodegeneration were found after 8 and 16 weeks of ischemia, respectively.

Conclusions

Prolonged ischemia may be a mediating variable in progression of overactive bladder to dysfunctional patterns similar to detrusor underactivity. The mechanism appears to involve differential expression of M1, M2, and M3 receptors, neural structural injury, and progressive loss of nerve fibers.