The Underactive Bladder: A New Clinical Concept?

How do we make progress in phenotyping patients with lower urinary tract such as overactive bladder and underactive detrusor, including using urine markers and microbiome data, to personalize therapy? ICI-RS 2023-Part 2

INTRODUCTION

Overactive bladder (OAB) and underactive bladder (UAB) could be associated with metabolic syndrome, affective disorders, sex hormone deficiency, changes in urinary microbiota, functional gastrointestinal disorders, or autonomic nervous system dysfunction.

OBJECTIVES

The aim of this Think Tank was to provide a guide on how to investigate OAB and/or detrusor underactivity (DU) patients to better clarify the underlying pathophysiology and possibly personalize the treatment.

METHODS

A compendium of discussion based on the current evidence related to phenotyping patients with OAB or DU using urodynamic tests, functional neuro-imaging, urinary markers, and microbiome.

RESULTS AND CONCLUSIONS

The article emphasizes the critical significance of adopting a comprehensive yet tailored approach to phenotyping patients with lower urinary tract (LUT) symptoms, such as OAB and UAB. The intricate interplay between the LUT and various factors, metabolic, neurological, psychological, and gastrointestinal can define unique LUT profiles, enabling personalized therapies to replace the one-size-fits-all approach.

Effect of detrusor underactivity on surgical outcomes of holmium laser enucleation of the prostate

OBJECTIVE

To evaluate the effect of detrusor underactivity (DUA) on the postoperative outcomes of holmium laser enucleation of the prostate (HoLEP) in patients with benign prostatic hyperplasia (BPH).

PATIENTS AND METHODS

Patients with BPH who underwent HoLEP between January 2018 and December 2022 were enrolled in this prospective database study. Patients were divided into DUA (bladder contractility index [BCI] <100) and non-DUA (BCI ≥100) groups. Objective (maximum urinary flow rate [Qmax], post-void residual urine volume [PVR]) and subjective outcomes (International Prostate Symptom Score [IPSS], Overactive Bladder Symptom Score [OABSS], satisfaction with treatment question [STQ], overall response assessment [ORA], and willingness to undergo surgery question [WUSQ]) were compared between the two groups before surgery, and at 3 and 6 months after HoLEP.

RESULTS

A total of 689 patients, with a mean (standard deviation [SD]) age of 69.8 (7.1) years, were enrolled. The mean (SD) BCI in the non-DUA (325 [47.2%]) and DUA (364 [52.8%]) groups was 123.4 (21.4) and 78.6 (14.2), respectively. Both objective (Qmax and PVR) and subjective (IPSS, IPSS-quality of life, and OABSS) outcomes after surgery significantly improved in both groups. The Qmax was lower in the DUA than in the non-DUA group postoperatively. At 6 months postoperatively, the total IPSS was higher in the DUA than in the non-DUA group. There were no significant differences in surgical complications between the two groups. Responses to the STQ, ORA, and WUSQ at 6 months postoperatively demonstrated that the patients were satisfied with the surgery (90.5% in the DUA group; 95.2% in the non-DUA group), their symptoms improved with surgery (95.9% in the DUA group; 100.0% in the non-DUA group), and they were willing to undergo surgery again (95.9% in the DUA group; 97.9% in the non-DUA group). There were no significant differences in the responses to the STQ and WUSQ between the two groups.

CONCLUSION

Our midterm results demonstrated that patients with BPH and DUA showed minimal differences in clinical outcomes after HoLEP compared to those without DUA. The overall satisfaction was high in the DUA group.

(A)voiding misdiagnosis: prediction of detrusor underactivity vs. bladder outlet obstruction using pre-urodynamic nomogram in male patients with LUTS

PURPOSE

Our study aimed to develop a noninvasive model using a combination of the set of clinical data and uroflowmetry (UFL) to differentiate between detrusor underactivity (DU) and bladder outlet obstruction (BOO) in non-neurogenic male patients with lower urinary tract symptoms (LUTS).

METHODS

Data from 229 men with LUTS, diagnosed with DU or BOO on a pressure-flow study (PFS), were retrospectively analyzed, including medical history, Core Lower Urinary Tract Symptoms score (CLSS) questionnaire, UFL and PFS. Uni- and multivariate logistic regression were utilized for the prediction analyses.

RESULTS

Of the cohort, 128 (55.9%) patients were diagnosed with DU. A multivariate logistic regression analysis identified less prevalent nocturia (OR 0.27, p < 0.002), more prevalent intermittency (OR 2.33, p = 0.03), less prevalent weak stream (OR 0.14, p = 0.0004), lower straining points in CLSS (OR 0.67, p = 0.02), higher slow stream points in CLSS (OR 1.81, p = 0.002), higher incomplete emptying points in CLSS (OR 1.31, p < 0.02), lower PVR ratio (OR 0.20, p = 0.03), and present features of fluctuating (OR 2.00, p = 0.05), fluctuating-intermittent (OR 3.09, p < 0.006), and intermittent (OR 8.11, p = 0.076) UFL curve shapes as independent predictors of DU. The above prediction model demonstrated satisfactory accuracy (c-index of 0.783).

CONCLUSION

Our 10-factor model provides a noninvasive approach to differentiate DU from BOO in male patients with non-neurogenic LUTS, offering a valuable alternative to invasive PFS.

Methylglyoxal and Advanced Glycation End Products (AGEs): Targets for the Prevention and Treatment of Diabetes-Associated Bladder Dysfunction?

Methylglyoxal (MGO) is a highly reactive α-dicarbonyl compound formed endogenously from 3-carbon glycolytic intermediates. Methylglyoxal accumulated in plasma and urine of hyperglycemic and diabetic individuals acts as a potent peptide glycation molecule, giving rise to advanced glycation end products (AGEs) like arginine-derived hydroimidazolone (MG-H1) and carboxyethyl-lysine (CEL). Methylglyoxal-derived AGEs exert their effects mostly via activation of RAGE, a cell surface receptor that initiates multiple intracellular signaling pathways, favoring a pro-oxidant environment through NADPH oxidase activation and generation of high levels of reactive oxygen species (ROS). Diabetic bladder dysfunction is a bothersome urological complication in patients with poorly controlled diabetes mellitus and may comprise overactive bladder, urge incontinence, poor emptying, dribbling, incomplete emptying of the bladder, and urinary retention. Preclinical models of type 1 and type 2 diabetes have further confirmed the relationship between diabetes and voiding dysfunction. Interestingly, healthy mice supplemented with MGO for prolonged periods exhibit in vivo and in vitro bladder dysfunction, which is accompanied by increased AGE formation and RAGE expression, as well as by ROS overproduction in bladder tissues. Drugs reported to scavenge MGO and to inactivate AGEs like metformin, polyphenols, and alagebrium (ALT-711) have shown favorable outcomes on bladder dysfunction in diabetic obese leptin-deficient and MGO-exposed mice. Therefore, MGO, AGEs, and RAGE levels may be critically involved in the pathogenesis of bladder dysfunction in diabetic individuals. However, there are no clinical trials designed to test drugs that selectively inhibit the MGO-AGEs-RAGE signaling, aiming to reduce the manifestations of diabetes-associated bladder dysfunction. This review summarizes the current literature on the role of MGO-AGEs-RAGE-ROS axis in diabetes-associated bladder dysfunction. Drugs that directly inactivate MGO and ameliorate bladder dysfunction are also reviewed here.

Summary Paper on Underactive Bladder from the European Association of Urology Guidelines on Non-neurogenic Male Lower Urinary Tract Symptoms

BACKGROUND AND OBJECTIVE

The European Association of Urology (EAU) Guidelines Panel on non-neurogenic male lower urinary tract symptoms (LUTS) aimed to develop a new subchapter on underactive bladder (UAB) in non-neurogenic men to inform health care providers of current best evidence and practice. Here, we present a summary of the UAB subchapter that is incorporated into the 2024 version of the EAU guidelines on non-neurogenic male LUTS.

METHODS

A systematic literature search was conducted from 2002 to 2022, and articles with the highest certainty evidence were selected. A strength rating has been provided for each recommendation according to the EAU Guideline Office methodology.

KEY FINDINGS AND LIMITATIONS

Detrusor underactivity (DU) is a urodynamic diagnosis defined as a contraction of reduced strength and/or duration, resulting in prolonged bladder emptying and/or failure to achieve complete bladder emptying within a normal time span. UAB is a terminology that should be reserved for describing symptoms and clinical features related to DU. Invasive urodynamics is the only widely accepted method for diagnosing DU. In patients with persistently elevated postvoid residual (ie, >300 ml), intermittent catheterization is indicated and preferred to indwelling catheters. Alpha-adrenergic blockers are recommended before more invasive techniques, but the level of evidence is low. In men with DU and concomitant benign prostatic obstruction (BPO), benign prostatic surgery should be considered only after appropriate counseling. In men with DU and no BPO, a test phase of sacral neuromodulation may be considered.

CONCLUSIONS AND CLINICAL IMPLICATIONS

The current text represents a summary of the new subchapter on UAB. For more detailed information, refer to the full-text version available on the EAU website (https://uroweb.org/guidelines/management-of-non-neurogenic-male-luts).

PATIENT SUMMARY

The European Association of Urology guidelines on underactive bladder in non-neurogenic adult men are presented here. Patients must be fully informed of all relevant options and, together with their treating physicians, decide on the most optimal management for them.

Intravesical Electrical Stimulation Improves Abnormal Prefrontal Brain Activity in Patients With Underactive Bladder: A Possible Central Mechanism

PURPOSE

The aim of this study was to explore the mechanisms of central brain action in patients with neurogenic underactive bladder (UAB) treated with intravesical electrical stimulation (IVES).

METHODS

We prospectively recruited patients with neurogenic UAB who chose to receive IVES treatment and healthy subjects (HS). At baseline, the following data were obtained: a 72-hour voiding diary; measurements of postvoid residual urine (PVR), voiding efficiency (VE) and first sensation of bladder filling (FS); American Urological Association Symptom Index Quality of Life (AUA-SI-QOL) scores, and functional near-infrared spectroscopy scans of the prefrontal cortex in the voiding stage. All UAB patients were re-evaluated for these indices after completing 4 weeks of IVES. A >50% improvement in PVR was defined as successful IVES treatment. Prefrontal activity was analyzed using the NIRS_KIT software, corrected with the false discovery rate (P<0.05). Statistical analysis was performed using IBM SPSS Statistics ver. 22.0, and P<0.05 was considered statistically significant.

RESULTS

Eighteen UAB patients and 16 HS were included. IVES treatment was successful in 11 UAB patients and failed in 7. The PVR, VE, 24-hour clean intermittent catheterization, FS volume, and AUA-SI-QOL scores of the UAB group significantly improved after successful IVES treatment. BA9 (right dorsolateral prefrontal cortex [DLPFC]) and BA10 (right frontal pole) were significantly activated after successful IVES, and no significant difference was found between the successful group and HS group after IVES. Before IVES, BA10 (right frontal pole) was significantly deactivated in the failed group compared with the successful group.

CONCLUSION

The possible central mechanism of IVES treatment for neurogenic UAB is that IVES reactivates the right DLPFC and right frontal pole.

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.

Transcriptomics Reveals Molecular Features of the Bilateral Pelvic Nerve Injury Rat Model of Detrusor Underactivity

The pathogenesis of detrusor underactivity (DU) is unclear, and the available therapeutic effects are unsatisfactory. We propose to find key molecules and pathways related to DU based on transcriptome sequencing. A rat model of bilateral pelvic nerve injury (BPNI) was established. Bladder tissues from the sham-operated group, 3 and 28 days after BPNI mapping, were taken for urodynamics, histopathology, and RNA-seq. An enrichment analysis of the screened differential expression genes was performed. Three days after BPNI, the results showed urodynamic features of overflow incontinence, while there was a recovery at 28 days after the operation. Masson staining revealed collagen deposition accompanied by progressive thickening of the smooth muscle layer as DU progressed. RNA-seq results suggested that a total of 1808 differentially expressed genes (DEGs) differed among the groups. RNA-seq and subsequent analysis confirmed that the cell cycle and immune response were significantly activated 3 days after BPNI, while extracellular matrix remodeling occurred 28 days after BPNI. Partial DEGs and pathways were verified by qRT-PCR. Validation of key proteins involved in cell cycle, inflammation, and fibrosis was performed by immunohistochemical staining and western blot, respectively. These molecular expression patterns at different time points after BPNI injury provide valuable insights into the search for therapeutic targets for DU.

Role of opioid and β-adrenergic receptors in bladder underactivity induced by prolonged pudendal nerve stimulation in cats

AIMS

To determine the role of opioid and β-adrenergic receptors in bladder underactivity induced by prolonged pudendal nerve stimulation (PNS).

METHODS

In α-chloralose anesthetized cats, 30-min PNS was applied repeatedly for 3-9 times to induce poststimulation or persistent bladder underactivity. Then, naloxone (opioid receptor antagonist, 1 mg/kg, IV) or propranolol (β-adrenergic receptor antagonist, 3 mg/kg, IV) was given to reverse the bladder underactivity. After the drug treatment, an additional 30-min PNS was applied to counteract the drug effect. Repeated cystometrograms were performed by slowly (1-2 mL/min) infusing the bladder with saline via a urethral catheter to determine the bladder underactivity and the treatment effects.

RESULTS

Prolonged (2-4.5 h) PNS induced bladder underactivity evident as a large bladder capacity (169 ± 49% of control) and a reduced amplitude of bladder contraction (59 ± 17% of control). Naloxone fully reversed the bladder underactivity by reducing bladder capacity to 113 ± 58% and increasing the amplitude of bladder contraction to 104 ± 34%. After administration of naloxone an additional 30-min PNS temporarily increased the bladder capacity to the underactive bladder level (193 ± 74%) without changing the amplitude of the bladder contraction. Propranolol had no effect on bladder underactivity.

CONCLUSIONS

A tonic enkephalinergic inhibitory mechanism in the CNS plays a critical role in the bladder underactivity induced by prolonged PNS, while the peripheral β-adrenergic receptor mechanism in the detrusor is not involved. This study provides basic science evidence consistent with the clinical observation that comorbid opioid usage may contribute to voiding dysfunction in patients with Fowler's syndrome.

Loss of resilience contributes to detrusor underactivity in advanced age

Volume hyposensitivity resulting from impaired sympathetic detrusor relaxation during bladder filling contributes to detrusor underactivity (DU) associated with aging. Detrusor tension regulation provides an adaptive sensory input of bladder volume to the brainstem and is challenged by physiological stressors superimposed upon biological aging. We recently showed that HCN channels have a stabilizing role in detrusor sympathetic relaxation. While mature mice maintain homeostasis in the face of stressors, old mice are not always capable. In old mice, there is a dichotomous phenotype, in which resilient mice adapt and maintain homeostasis, while non-resilient mice fail to maintain physiologic homeostasis. In this DU model, we used cystometry as a stressor to categorize mice as old-responders (old-R, develop a filling/voiding cycle) or old-non-responders (old-NR, fail to develop a filling/voiding cycle; fluctuating high pressures and continuous leaking), while also assessing functional and molecular differences. Lamotrigine (HCN activator)-induced bladder relaxation is diminished in old-NR mice following HCN-blockade. Relaxation responses to NS 1619 were reduced in old-NR mice, with the effect lost following HCN-blockade. However, RNA-sequencing revealed no differences in HCN gene expression and electrophysiology studies showed similar percentage of detrusor myocytes expressing HCN (I_h) current between old-R and old-NR mice. Our murine model of DU further defines a role for HCN, with failure of adaptive recalibration of HCN participation and intensity of HCN-mediated stabilization, while genomic studies show upregulated myofibroblast and fibrosis pathways and downregulated neurotransmitter-degradation pathways in old-NR mice. Thus, the DU phenotype is multifactorial and represents the accumulation of age-associated loss in homeostatic mechanisms.

Randomized controlled trial of intravesical electrical stimulation for underactive bladder

AIM

To evaluate the efficacy and safety of intravesical electrical stimulation (IVES) performed with a novel device in patients with underactive bladder (UAB).

PATIENTS AND METHODS

This was a multicentre, prospective, single-blind, randomized controlled clinical trial of patients with UAB in China. Eligible patients were randomly assigned in a 1:1 ratio to receive conventional IVES (n = 38) or IVES with an open circuit (n = 38). The primary efficacy measure was change from baseline in post-void residual urine volume (PVR) after 4 weeks of treatment. Secondary efficacy measures included changes in maximum urinary flow rate (Q_max ), bladder voiding efficiency (BVE), number of 24-h clean intermittent catheterization (CIC) procedures, and Patient Perception of Bladder Condition-Scale (PPBC-S) and American Urological Association Symptom Index Quality of Life (AUA-SI-QoL) scores from baseline after 4 weeks of treatment. Adverse events (AEs) were monitored throughout the trial.

RESULTS

In the full analysis set (FAS), the mean (sd) PVR changes in the trial and control groups at 4 weeks were -97.1 (107.5) mL and -10.5 (86.7) mL, respectively (P < 0.01). Similar results were obtained in the per-protocol set (PPS): -102.9 (100.0) mL vs 0.7 (82.5) mL (P < 0.01). In the FAS and PPS, Q_max improved significantly at 4 weeks (P = 0.04 and P = 0.03). In the FAS and PPS, BVE was significantly improved at 4 weeks in the two groups (P < 0.01 and P < 0.01), whereas no significant differences in the number of 24-h CIC procedures, PPBC-S score or AUA-SI-QoL score were observed between the groups. Six possible therapy-related AEs occurred in six patients (four in the trial group and two in the control group; P = 0.67), all of which were urinary tract infections. No severe AEs were reported.

CONCLUSIONS

The results of this clinical study strongly demonstrate that UAB patients benefit from this novel IVES device. More research is needed to validate the clinical utility of this device.

Detrusor Underactivity in Men with Bladder Outlet Obstruction

Detrusor underactivity (DU) and bladder outlet obstruction (BOO) are both common troublesome causes of lower urinary tract symptoms (LUTS) and often impact on quality of life simultaneously in men. This article aims to focus on DU with BOO in male patients.

METHODS

Original articles concerning DU with BOO were identified through literature research from PubMed and EMBASE database. We selected 38 articles in our review, including those concerning pathophysiology, evaluation, treatment and predictors for a successful BOO surgery for DU.

RESULTS

DU from BOO can result from several pathophysiological mechanisms. Although urodynamic study (UDS) is considered as a precise method to diagnose DU and BOO, there are some previous studies which proposed a non-invasive method to identify DU related to BOO. The treatment goal of DU is restoring bladder contractility using medication or surgery. Releasing outlet obstruction and resistance is the main strategy to restore bladder contractility when medication to directly increase bladder contractility has had limited efficacy.

CONCLUSIONS

DU from BOO is poorly understood and is largely under-researched. The etiology and pathophysiology still need to be evaluated. Effective and safe medication to restore bladder contractility is also lacking. It remains valuable to perform further research to reveal the unknown aspects of DU.

Clinical features of detrusor underactivity in elderly men without neurological disorders

OBJECTIVES

To investigate the clinical features of detrusor underactivity (DU) in elderly men without neurological disorders.

METHODS

A total of 336 men aged ≥50 years without neurogenic disorders who underwent pressure flow studies and who had DU or bladder outlet obstruction (BOO) were reviewed retrospectively. According to the bladder contractility index (BCI) and the BOO index (BOOI), the subjects were classified into the following three groups: (a) pure DU group, BCI < 100 and BOOI < 40; (b) DU + BOO group, BCI < 100 and BOOI ≥ 40; and (c) pure BOO group, BCI ≥ 100 and BOOI ≥ 40. Subjective and objective parameters were compared among the three groups, and the predictors for pure DU were evaluated by multivariate analysis.

RESULTS

Of the 336 patients, 205 who met the study criteria were included in the analysis: 63 (30.7%) with pure DU, 48 (23.4%) with DU + BOO, and 94 (45.9%) with pure BOO. The proportion of the pure DU group increased with increasing age. Prostate volume was the lowest in the pure DU group. Frequency, urgency on the International Prostate Symptom Score (IPSS), and the IPSS storage subscore were the lowest in the pure DU group. Multivariate analysis showed that age (odds ratio [OR] 1.114 [95% CI, 1.032-1.203], P = .005), prostate volume (OR 0.968 [95% CI, 0.949-0.987], P = .001), and urgency (OR 0.623 [95% CI, 0.431-0.900], P = .012) were predictors of pure DU.

CONCLUSION

Older age, smaller prostate volume, and less urgency may be clinical features of pure DU.

Detrusor underactivity prevalence and risk factors according to different definitions in women attending urogynecology clinic

INTRODUCTION AND HYPOTHESIS

There is still no consensus on definitions of detrusor underactivity; therefore, it is difficult to estimate the prevalence. The primary objective of the study was to evaluate the prevalence of detrusor underactivity in a cohort of patients with pelvic floor disorders according to different proposed urodynamics definitions. The secondary objectives were to estimate the association between detrusor underactivity and symptoms, anatomy and urodynamic findings and to build predictive models.

METHODS

Patients who performed urodynamic evaluation for pelvic floor disorders between 2008 and 2016 were retrospectively analyzed. Detrusor underactivity was evaluated according to Schafer's detrusor factor, Abrams' bladder contractility index and Jeong cut-offs. The degree of concordance between each method was measured with Cohen's kappa, and differences were tested using Student's t test, Wilcoxon test and Pearson's chi-squared test.

RESULTS

The prevalence of detrusor underactivity among a cohort of 2092 women, concerning the three urodynamic definitions, was 33.7%, 37.0% and 4.1%, respectively. Age, menopausal status, voiding/bulging symptoms, anterior and central prolapse, first desire to void and positive postvoid residual were directly related to detrusor underactivity. Conversely, stress urinary incontinence, detrusor pressures during voiding and maximum flow were inversely associated. Final models for detrusor underactivity resulted in poor accuracy for all considered definitions.

CONCLUSIONS

The prevalence of detrusor underactivity varies depending on the definition considered. Although several clinical variables resulted as independent predictors of detrusor underactivity, instrumental evaluation still plays a key role in the diagnosis.

Non-invasive diagnosis of under active bladder: A pilot study

OBJECTIVE

We assessed the efficacy of voiding efficiency (VE) to distinguish between underactive bladder (UB) and bladder outlet obstruction (BO) without using pressure flow studies (PFS).

MATERIALS AND METHODS

in male patients, uroflowmetry and post-void residual (PVR) urine data and subsequent pressure flow studies (PFS) data were examined retrospectively. Bladder outlet obstruction index (BOI) and bladder contractility index (BCI) were calculated from patients' PFS values. Patients with BCI < 100 and BOI < 40 were grouped as UB group and patients with BCI > 100 and BOI > 40 were grouped as BOO group. VE was computed as a percentage of volume voided compared to the pre-void bladder volume.

RESULTS

In total we examined 93 patients, 44 in UB and 49 in BO group. There was no statistically significant difference between the two groups in relation to Qmax value (p = 0.38). However, total voiding time, time to reach the maximum urinary flow rate and voided volume showed statistically significant difference between the two groups (p < 0.001). Average VE was 63.6 + 2.43% and 46.2 + 2.63%) for UB and BO groups respectively and the difference was statistically significant (p < 0.001). UB can be diagnosed with at least 95% sensitivity and 88% specificity in men over age 80.

CONCLUSIONS

Non-invasive uroflowmetry and VE measurements were able to differentiate between UB and BOO patients, presenting with identical clinic features, but different findings of PFS.

Treatment outcomes of detrusor underactivity in women based on clinical and videourodynamic characteristics

PURPOSE

Treatment of voiding dysfunction due to detrusor underactivity (DU) remains challenging. This study sought to determine the characteristics of video urodynamic study (VUDS) in female DU and outcomes after active treatment.

METHODS

A total of 409 female patients with VUDS-proven DU were recruited. All patients received conservative bladder management, with others receiving active treatment, such as oral medication, transurethral incision of bladder neck (TUI-BN), surgery for prolapse, and urethral botulinum toxin A (BoNT-A) injection, according to their VUDS characteristics. Treatment outcomes were then analyzed by different VUDS characteristics.

RESULTS

Satisfactory treatment outcomes were noted in 123 patients (30.0%), among whom 35 and 88 had a VE of > 90% and > 66.7%, respectively. A total of 165 patients (40.3%) had voiding efficiency (VE) of 33.3-66.7%, whereas 121 (29.6%) remained unable to void (12.5%) or had a VE of < 33.3% (17.1%). Conservative treatment had the worst outcome. Patients with normal or slightly reduced bladder sensation (49.3%) and those with a post-void residual (PVR) of < 250 mL (59.4%) displayed better satisfactory outcome after treatment; while TUI-BN and urethral BoNT-A injection promoted better treatment results. Patients with detrusor acontractility and a PVR of ≥ 500 mL still achieved high VE rates (> 66.7%) after TUI-BN. A 56.3% satisfactory outcome was achieved after TUI-BN, whereas 58.1% satisfactory outcome was noted in those with a tight external sphincter after medical treatment.

CONCLUSION

Female patients with DU exhibited VE improvement after active treatment. Patients with very low detrusor contractility and absent bladder sensation generally exhibited poor treatment outcomes.

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.

Underactive urinary bladder – Masquerading as abdominal ascites

An impaired ability to evacuate the urinary bladder is commonly seen in both men and women with aging. Usually, patients present with a range of storage, voiding, and post-micturition urinary symptoms. It may eventually lead to urinary retention. These symptoms may have a considerable effect on the patient’s quality of life. Despite its common prevalence with advancing age, the etiopathogenesis of the underactive urinary bladder is incompletely understood. There are no widely agreed diagnostic criteria. The urodynamic study (UDS), an invasive investigation is the only accepted modality to diagnose underactive detrusor. There is a lack of effective treatments to improve bladder emptying. The goals of treatment are to improve symptoms and reduce the risk for the complications of impaired bladder emptying. We report a case of a 73 year male who came to us with a history of urinary symptoms and a distended abdomen.

Urodynamic autonomic bladder dysfunction in women with complex chronic pelvic pain is associated with small fiber polyneuropathy

AIMS

Small fiber neuropathy/polyneuropathy (SFN) has been found to be present in 64% of complex (refractory or multisystem) chronic pelvic pain (CPP) patients. The small fiber dysfunction seen in SFN can negatively impact autonomic control of micturition in addition to pain. This study investigated the clinical association of autonomic dysfunction (detrusor underactivity and primary bladder neck obstruction [BNO]) on video urodynamics (VUDS) with SFN in patients with CPP.

METHODS

This was a retrospective observational study, querying data from patients with complex CPP. Inclusion criteria were: the presence of complex (refractory or multisystem) CPP, and completion of both (1) subspecialty autonomic neurology evaluation for SFN and (2) high-quality VUDS performed according to ICS standards. Autonomic bladder dysfunction (BNO or detrusor underactivity) on VUDS was compared to the presence of SFN.

RESULTS

Thirty-two female patients with complex CPP met criteria. Of the 32, 23 (72%) were found to have SFN. Patient with autonomic bladder dysfunction (BNO or detrusor underactivity) were more likely to have SFN (OR = 9.5 [95% CI: 1.641, 55.00], p = 0.007). Post-void residual volume was higher in the SFN group (p = 0.011 [95% CI: 13.12, 94.0]) and symptoms of urge urinary incontinence were more likely to be present (p = 0.000 [95% CI: -3.4, -1.25]).

CONCLUSIONS

Patients with complex CPP with autonomic bladder dysfunction are more likely to have SFN. This suggests patients with complex CPP should be considered for diagnosis and treatment of SFN, particularly if BNO or detrusor underactivity is noted on VUDS evaluation.

The effectiveness of parasympathomimetics for treating underactive bladder: A systematic review and meta-analysis

AIMS

Biological rationale suggests that parasympathomimetics (cholinergic receptor stimulating agents) could be beneficial for patients with underactive bladder. However, no systematic review with meta-analysis addressing potential benefits or adverse effects exists. The aim of this review was to assess the effectiveness, both benefits and harms, of using parasympathomimetics for the treatment of underactive bladder.

METHODS

The protocol was registered in PROSPERO, and searches undertaken in PubMed, Embase, and CENTRAL, including randomized and non-randomized controlled trials of patients with underactive bladder, comparing parasympathomimetic to placebo, no treatment, or other pharmaceuticals. Risk ratios, odds ratios, and mean differences were calculated.

RESULTS

Twelve trials with 3024 participants were included. There was a significant difference between parasympathomimetics and comparators (favoring parasympathomimetics) in the number of patients with urinary retention (risk ratio 0.55, 95% confidence interval [CI] 0.3-0.98, p = 0.04, low quality of evidence). There was no difference in mean postvoid volume overall (MD -41.4 ml, 95% CI -92.0 to 9.1, p = 0.11, low quality of evidence). There was a significant difference at up to 1 week post-intervention, favoring parasympathomimetics (MD -77.5 ml, 95% CI -90.9 to -64.1, p < 0.001, low quality of evidence), but no difference at 1 month post-intervention. There was no difference in adverse events (odds ratio 1.19, 95% CI 0.62-2.28, p = 0.6, moderate quality of evidence).

CONCLUSIONS

The evidence supporting the use of parasympathomimetics is of low quality, with relatively short follow-up durations. Overall, it is not possible to draw clear evidence-based conclusions from the current literature, presenting the use of parasympathomimetics for treating underactive bladder as a key area that requires future well-controlled clinical trials.

[Female voiding dysfunction: Clean intermittent catheterization is not the only option]

Female voiding dysfunction exists but are largely underdiagnosed, especially in France. They can result from two different mechanisms: detrusor underactivity or bladder outlet obstruction, with very different pathophysiology and therapeutic management. There are many different therapeutic options, including surgical treatments, to offer as alternative to clean intermittent catheterization which are often burdensome for patients. Seeking voiding dysfunction in female patients with lower urinary tract symptoms and searching for their etiology to tackle it could lead to a paradigm change in these women: from standardized treatment to individualized treatment. In their practice, nurses can detect warning symptoms suspect of voiding dysfunction, and have thus a role to play in the improvement of patients' screening, education other healthcare providers, and management of female voiding dysfunction.

Dysfunctional voiding behavior and impaired muscle contractility in a rat model of detrusor underactivity

AIMS

Detrusor underactivity (DU) is an understudied health concern with inadequate clinical management. The pathophysiology of DU is unclear, and current therapies fail to improve symptoms. The current studies characterized voiding function and contractility of bladder and urethral tissues in a novel rat model of DU.

METHODS

Female obese prone (OP) and obese resistant (OR) rats were fed a 60 kcal% fat diet at 8 weeks old. A subset of rats (n = 4/strain) underwent uroflowmetry biweekly for 18 weeks in metabolic cages. At 40-56 weeks old, rats (n = 9-10/strain) underwent instrumented cystometry under urethane anesthesia. Following cystometry, bladder and urethral tissues (n = 8-9/strain) were harvested for in vitro assessments of contractility in response to carbachol, electric field stimulation, atropine, alpha, beta-methylene ATP, and caffeine.

RESULTS

OP rats exhibited increased urinary frequency (p = 0.0031), decreased voided volume (p = 0.0093), and urine flow rate (p = 0.0064) compared to OR rats during uroflowmetry. Bethanechol (10 mg/kg) did not alter uroflowmetry parameters. During cystometry, OP rats exhibited decreased bladder emptying efficiency (p < 0.0001), decreased pressure to generate a void (p < 0.0001), and increased EUS activity during filling (p = 0.0011). Bladder contractility was decreased in OP rats when exposed to carbachol (p < 0.0003) and ATP (p = 0.0004), whereas middle urethral contractility was increased when exposed to carbachol (p = 0.0014), EFS (p = 0.0289), and caffeine (p = 0.0031).

CONCLUSION

Impaired cholinergic and purinergic signaling in the bladder may contribute to poor voiding function in OP rats. In addition, increased urethral activity may engage a guarding reflex to augment continence and exacerbate incomplete emptying.

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.

Success of endoscopic prostatic surgery in patients with DUA: a prospective observational and analytic study

Introduction:

Detrusor underactivity (DUA) is a highly prevalent and poorly understood disease in urology practice. Conservative treatment in the form of clean intermittent catheterization (CIC) and pharmacotherapy are in use for DUA without good results. Endoscopic prostate surgery was initially considered ineffective in such patients. But a recent series of retrospective studies showed promising results of surgery in DUA. Therefore, we conducted this prospective study to evaluate success of endoscopic prostatic surgery in a patient with DUA.

Materials and methods:

This is prospective observational study of 50 patients, satisfying the inclusion criteria, at Ruby Hall Clinic, Pune, conducted between March 2017 and March 2019. Inclusion criteria are that the patients are male, aged > 50 years; urodynamically diagnosed with DUA; a bladder contractility index < 90 with associated bladder outlet obstruction index (BOOI) between 20–40 (equivocal) or > 40 (obstruction), who presented with lower urinary tract symptoms and poor flow ( Qmax < 10 ml/s in a voided volume of >150 ml. Patients were excluded from the study if they had DUA due to neurological causes or spinal trauma, an acontractile detrusor, and were < 50 years.

Results:

The follow-up period for each patient was 12 months. The mean international prostate specific score reduced from 24.82 ± 2.74 preoperatively to 4.4 ± 1.85 postoperatively. Mean quality of life score reduced from 4.06 ± 0.68 to 0.82 ± 0.62. Mean Qmax increased from 6.26 ±1.46 ml/s to 12.22 ±1.6 ml/s. Mean post-void residual urine volume reduced form 241.9 ±74.9 to 77.3 ±20.75. All of these were statistically significant with a p value < 0.00001.

Conclusion:

Transurethral resection of the prostate (monopolar/laser) to reduce BOO should be considered as an alternative, viable treatment option in men with DUA. Preoperative counselling and postoperative follow-up are crucial in the management of such patients. Level of evidence:

Symptoms of voiding dysfunction and other coexisting pelvic floor dysfunctions: the impact of transvaginal, mesh-augmented sacrospinous ligament fixation

INTRODUCTION AND HYPOTHESIS

The objective was to investigate the prevalence for voiding dysfunction and if symptom improvement can be achieved by adequate pelvic floor surgery.

METHODS

We evaluated the Propel Study data from 281 women with pelvic organ prolapse (POP) stage 2-4. Bother caused by obstructive micturition, voiding dysfunction, and coexisting pelvic floor symptoms were assessed using the Pelvic Floor Distress Inventory (PFDI) preoperatively and 6, 12, and 24 months after vaginal prolapse repair. Successful reconstruction (Pelvic Organ Prolapse Quantification [POP-Q] stage 0-I throughout the 2-year follow-up at all compartments, "responders"), was compared with all others ("non-responders").

RESULTS

Prevalence of voiding dysfunction was significantly reduced after surgery for all patients with "moderate" to "quite a bit" of bother ("R2") regarding all examined PFDI questions. Defects of the posterior/apical compartment and lower stage defects were found to cause obstructive micturition, which improved significantly after POP surgery. Six months after surgery, the prevalence of R2 for voiding dysfunction symptoms was reduced significantly for responders compared with non-responders. Significant reduction of R2 in patients with rectoceles could be shown for some PFDI questions, whereas the rate was lower in patients with cystoceles. Other pelvic floor symptoms often coexisted in patients with voiding dysfunction symptoms and improved significantly after surgery as well.

CONCLUSIONS

Symptoms of voiding dysfunction are frequent in female patients with POP and can significantly improve after vaginal mesh-augmented prolapse repair even for posterior and minor defects. Before counseling patients to undergo POP surgery because of their obstructive symptoms, other causes of voiding dysfunction must first have been ruled out.

Bladder underactivity induced by prolonged pudendal afferent activity in cats

The purpose of this study was to determine the effects of pudendal nerve stimulation (PNS) on reflex bladder activity and develop an animal model of underactive bladder (UAB). In six anesthetized cats, a bladder catheter was inserted via the urethra to infuse saline and measure pressure. A cuff electrode was implanted on the pudendal nerve. After determination of the threshold intensity (T) for PNS to induce an anal twitch, PNS (5 Hz, 0.2 ms, 2 T or 4 T) was applied during cystometrograms (CMGs). PNS (4-6 T) of 30-min duration was then applied repeatedly until bladder underactivity was produced. Following stimulation, control CMGs were performed over 1.5-2 h to determine the duration of bladder underactivity. When applied during CMGs, PNS (2 T and 4 T) significantly (P < 0.05) increased bladder capacity while PNS at 4 T also significantly (P < 0.05) reduced bladder contraction amplitude, duration, and area under contraction curve. Repeated application of 30-min PNS for a cumulative period of 3-8 h produced bladder underactivity exhibiting a significantly (P < 0.05) increased bladder capacity (173 ± 14% of control) and a significantly (P < 0.05) reduced contraction amplitude (50 ± 7% of control). The bladder underactivity lasted more than 1.5-2 h after termination of the prolonged PNS. These results provide basic science evidence supporting the proposal that abnormal afferent activity from external urethral/anal sphincter could produce central inhibition that underlies nonobstructive urinary retention (NOUR) in Fowler's syndrome. This cat model of UAB may be useful to investigate the mechanism by which sacral neuromodulation reverses NOUR in Fowler's syndrome.

Transcutaneous Electrical Nerve Stimulation and Percutaneous Tibial Nerve Stimulation to Treat Idiopathic Nonobstructive Urinary Retention: A Systematic Review

CONTEXT

Transcutaneous electrical nerve stimulation (TENS) and percutaneous tibial nerve stimulation (PTNS) provide minimally invasive ways to treat idiopathic nonobstructive urinary retention (NOUR).

OBJECTIVE

To assess the efficacy of TENS and PTNS for treating idiopathic NOUR.

EVIDENCE ACQUISITION

A systematic review was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) statement. Embase, Medline, Web of Science Core Collection, and the Cochrane CENTRAL register of trials were searched for all relevant publications until April 2020.

EVIDENCE SYNTHESIS

A total of 3307 records were screened based on the title and abstract. Eight studies met the inclusion criteria and none of the exclusion criteria. Five studies, all from the same group, reported the efficacy of PTNS and two that of TENS in adults with idiopathic NOUR. One study reported the efficacy of TENS in children with idiopathic NOUR. Objective success was defined as a ≥50% decrease in the number of catheterizations per 24 h or in the total catheterized volume in 24 h. The objective success rate of PTNS ranged from 25% to 41%. Subjective success was defined as the patient's request for continued chronic treatment with PTNS, and ranged from 46.7% to 59%. Eighty percent of women who underwent transvaginal stimulation reported an improvement such as a stronger stream when voiding. TENS in children reduced postvoid residual and urinary tract infections.

CONCLUSIONS

The efficacy of TENS and PTNS in the treatment of idiopathic NOUR is limited and should be verified in larger randomized studies before application in clinical practice.

PATIENT SUMMARY

The outcomes of transcutaneous electrical nerve stimulation and percutaneous tibial nerve stimulation for the treatment of urinary retention of unknown origin were reviewed. Whether these treatments are superior to other treatments could not be established.

Do urodynamics predict urinary retention after sling placement in the complex patient: the value of reproducing symptoms on urodynamics

INTRODUCTION AND HYPOTHESIS

To examine urinary retention (UR) after female urethral sling placement in patients with or without detrusor underactivity (DU) or Valsalva voiding whose urodynamics (UDS) accurately reproduced voiding symptoms to determine whether the reproduction of voiding symptoms on UDS in those with DU is predictive of UR after sling placement.

METHODS

We performed a review of patients undergoing urethral sling procedures for stress urinary incontinence (SUI) looking specifically at the occurrence of short- and long-term urinary retention. Preoperative UDS data were obtained from a prospectively acquired UDS database in which patients were directly queried at the time of the UDS study about whether the filling and/or storage phase of the study reproduced their usual symptoms.

RESULTS

Of the 141 women who had a urethral sling procedure, 124 (87.9%) had preoperative UDS. Of those who had UDS, 41 (33%) had de novo UR at some point postoperatively. Compared to those without DU, patients with DU and/or Valsalva voiding were more likely to have UR (75.6% vs. 56.6%, p = 0.04). There was no difference in association of UR in patients with DU/Valsalva voiding whose UDS reproduced voiding symptoms compared to those with DU/Valsalva voiding whose UDS did not reproduce symptoms (OR 1.01, CI 0.32-3.19, p 0.98).

CONCLUSIONS

This study found that patients with DU/Valsalva voiding had an increased association with UR but did not find reproduction of symptoms on UDS to correlate with UR in either those with DU/Valsalva voiding or with normal bladder contractility.

Symptoms and noninvasive test parameters that clinically differentiate detrusor underactivity from bladder outlet obstruction without a pressure-flow-based diagnosis in men with lower urinary tract symptoms

AIM

To examine the symptoms and noninvasive test parameters that clinically differentiate detrusor underactivity (DU) from bladder outlet obstruction (BOO) without using a pressure-flow study (PFS) in male patients with lower urinary tract symptoms.

METHODS

We examined 909 men who underwent PFS and also had the following data: International Prostate Symptom Score (IPSS), free uroflowmetry, postvoid residual (PVR), and prostate volume (PV). Using these data, significant symptoms and noninvasive test parameters that clinically differentiate DU from BOO were examined.

RESULTS

Significant parameters between DU patients and BOO patients were older age, smaller PV, and lower urgency symptom score (IPSS Q4). Optimal cutoff values were determined using receiver operating characteristic curves (≥74 years old, PV ≤ 34.8, and IPSS Q4 ≤ 1) and patients were categorized on the basis of the number of significant factors. The probability of DU or BOO in patients with three significant factors were 77% and 34%, respectively.

CONCLUSION

Three factors (older age, smaller PV, and fewer urgency symptom) were the predictive factors to differentiate DU from BOO, which might be useful for estimating the probability of DU in clinical practice without a PFS.

Does detrusor underactivity affect the results of transurethral resection of prostate?

PURPOSE

We aimed to evaluate the outcome of transurethral resection of the prostate (TURP) in patients with benign prostatic hyperplasia (BPH) and diagnosed to have weak detrusor contractility by urodynamic study.

METHODS

A prospective study of 32 male patients had BPH candidate for TURP diagnosed to have impaired detrusor contractility by preoperative urodynamic study. We studied the postoperative outcome after TURP regarding international prostate symptoms score (IPSS), maximum flow rate (Q_max), post-voiding residual urine (PVR), the patients need for catheter, and urodynamic pressure flow study (PFS) parameters (maximum detrusor contractility, bladder contractility index (BCI), maximum bladder capacity and compliance) after 6 month follow-up.

RESULTS

Twenty-one cases presented with urethral catheter because of chronic or refractory retention. Twenty patients voided preoperatively during PFS with mean detrusor pressure (Pdet) at Q_max 23.97 ± 25.54 cmH2O and the mean BCI was 51.04 ± 23.86, while twelve patients did not void with mean maximum Pdet 21.75 ± 7.34. After 6 month follow-up, there was significant improvement in IPSS, Q_max, and detrusor contractility (Pdet at Q_max and BCI) postoperatively in all patients, and there was no significant postoperative improvement of post-voiding residual urine (p value 0.92). Finally, 11 patients voided normally without RU, 7 patients needed timed triple voiding with crede maneuver and small RU, and 14 patients needed CIC.

CONCLUSIONS

There were significant improvements in IPSS, detrusor contractility, and urine flow after TURP in patients with BPH and weak bladder contractility, although the risk of postoperative urine retention in approximately 43% of cases and needed CIC.

Clinical diagnostic criteria for detrusor underactivity: A report from the Japanese Continence Society working group on underactive bladder

Detrusor underactivity (DU) is a common bladder dysfunction that causes lower urinary tract symptoms (LUTS) in both men and women. Currently DU can only be diagnosed by an invasive urodynamic test. Underactive bladder (UAB) is the symptom-based correlate of DU, as is the case with overactive bladder (OAB) and detrusor overactivity (DO). The International Continence Society (ICS) consensus group has recently proposed a working definition of UAB as a symptom syndrome suggestive of DU. However, a symptom complex of UAB is shared by LUTS attributable to bladder outlet obstruction (BOO). Thus, UAB is not specific for DU, leading to difficulties in determining a therapeutic target (DU or BOO) in the initial management of UAB. Under these circumstances, a consensus group was formed under the auspices of the Japanese Continence Society (JCS) and diagnostic criteria were produced to potentially identify patients likely to have DU, without a pressure/flow study-based diagnosis. Certain symptoms and several noninvasive test parameters have been reported as clinical predictors of DU, and were suggested to discriminate DU from BOO. Of these predictive factors, the more commonly used parameters were used to develop clinical diagnostic criteria for DU. This article presents the clinical diagnostic criteria for DU proposed by the JCS consensus group and aims to summarize the background discussion by the group.

Therapeutic Efficacy of Human Embryonic Stem Cell-Derived Multipotent Stem/Stromal Cells in Diabetic Detrusor Underactivity: A Preclinical Study

Mesenchymal stem/stromal cell (MSC) therapy is a promising approach for treatment of as yet incurable detrusor underactivity (DUA), which is characterized by decreased detrusor contraction strength and/or duration, leading to prolonged bladder emptying. In the present study, we demonstrated the therapeutic potential of human embryonic stem cell (ESC)-derived multipotent MSCs (M-MSCs) in a diabetic rat model of DUA. Diabetes mellitus (DM) was induced by intraperitoneal injection of streptozotocin (STZ) (50 mg/kg) into 8-week-old female Sprague-Dawley rats. Three weeks later, various doses of M-MSCs (0.25, 0.5, and 1 × 10⁶ cells) or an equivalent volume of PBS were injected into the outer layer of the bladder. Awake cystometry, organ bath, histological, and gene expression analyses were evaluated 1 week (short-term) or 2 and 4 weeks (long-term) after M-MSC transplantation. STZ-induced diabetic rats developed DUA, including phenotypes with significantly longer micturition intervals, increased residual urine amounts and bladder capacity, decreased micturition pressure on awake cystometry, and contractile responses to various stimuli in organ bath studies. Muscle degeneration, mast cell infiltration, fibrosis, and apoptosis were present in the bladders of DM animals. A single local transplantation of M-MSCs ameliorated DUA bladder pathology, including functional changes and histological evaluation, and caused few adverse outcomes. Immunostaining and gene expression analysis revealed that the transplanted M-MSCs supported myogenic restoration primarily by engrafting into bladder tissue via pericytes, and subsequently exerting paracrine effects to prevent apoptotic cell death in bladder tissue. The therapeutic efficacy of M-MSCs was superior to that of human umbilical cord-derived MSCs at the early time point (1 week). However, the difference in efficacy between M-MSCs and human umbilical cord-derived MSCs was statistically insignificant at the later time points (2 and 4 weeks). Collectively, the present study provides the first evidence for improved therapeutic efficacy of a human ESC derivative in a preclinical model of DM-associated DUA.

Variability of post-void residual urine volume and bladder voiding efficiency in patients with underactive bladder

OBJECTIVES

Post-void residual urine volume (PVR) and bladder voiding efficiency (BVE) are widely used as clinical parameters to evaluate patients with voiding dysfunction. The present study was conducted to assess the variability of PVR and BVE determinations in patients with underactive bladder (UAB). In addition, we focused on the bladder volume prior to voiding (BV_void ) that may influence PVR and BVE, and investigated a correlation between PVR and BV_void , and between BVE and BV_void .

METHODS

Ten patients with a symptom complex of UAB, who had PVR of 50 mL or greater, were admitted to hospital during a 24-hour period for the measurement of voided volume (VV) and PVR. PVR was measured by transabdominal ultrasonography. BVE was expressed by a fraction (%) of bladder volume evacuated ([VV/BV_void ] × 100).

RESULTS

Ten patients, five men (mean age of 65.0 years) and five women (mean age of 70.2 years), participated in this study. Regardless of gender, there was a large variation in repeated measurements of PVR in an individual patient. PVR increased with an increase in BV_void , and there was a significant linear relationship between PVR and BV_void . BVE was approximately constant after every voiding in each patient, and there was no significant linear relationship between BVE and BV_void .

CONCLUSIONS

Measurement of PVR was unreliable because of wide variation in the same individual. The variation of BVE was much smaller than PVR. BVE would be a reliable parameter with good reproducibility for the assessment of emptying function.

Detrusor underactivity versus bladder outlet obstruction clinical and urodynamic factors

Objectives:

Methods:

Results:

Conclusion:

The role of clean intermittent catheterization in the treatment for detrusor underactivity

OBJECTIVE

To study the influence of clean intermittent catheterization (CIC) on the lower urinary tract function in patients with urinary retention (UR) due to detrusor underactivity (DU).

MATERIAL AND METHODS

A longitudinal study was carried out on 49 patients (28 men, 21 women) of mean age 55years, who underwent CIC for UR secondary to DU. The mean CIC frequency was 3.15 times/day. Patients' clinical data were collected, and they underwent urodynamic study before and after CIC, with a mean interval of 4years. Fisher's exact test was used for the analysis of categorical variables and Student's t test for parametric variables. The level of significance was set at 0.05 for a two-tailed test.

RESULTS

The second urodynamic study showed a significantly increased bladder compliance, the Bladder Outlet Obstruction Index (BOOI) and the Bladder Contractility Index (BCI) also increased but without reaching statistical significance. There was a significantly higher percentage of benign prostatic hyperplasia (BPH) and acontractile detrusor cases among the group of patients whose BCI improved after CIC, with significantly lower CIC time.

CONCLUSIONS

CIC improved bladder compliance in the patients of our series. The BCI improved in BPH patients and in patients with acontractile detrusor.

Pathophysiological changes of the lower urinary tract behind voiding dysfunction in streptozotocin-induced long-term diabetic rats

We evaluated pathophysiological characteristics of the lower urinary tract dysfunction in a streptozotocin (STZ)-induced diabetic rat model. STZ (60 mg/kg) was injected intraperitoneally into male Wistar rats. In vitro bladder muscle strip experiments, in vivo cystometry, and simultaneous recordings of bladder pressure + urethral perfusion pressure (BP + UPP) with or without intravenous administration of L-arginine (300 mg/kg) or tadalafil (0.03 mg/kg) were performed at several time points. In vitro muscle strip experiments demonstrated that diabetic rats had significantly higher contractile responses to carbachol at 4-16 weeks, and a tendency for higher contractile responses to electrical field stimulation at 4-12 weeks, but this was reversed at 16 weeks. Diabetic rats had significant increases in voided volume, residual volume, bladder capacity, maximal voiding pressure, and amplitude and frequency of non-voiding contractions at 16 weeks. Tadalafil decreased the residual volume in diabetic rats. Diabetic rats had significantly higher UPP nadir and mean UPP during high-frequency oscillation at 16 weeks, which were reversed by tadalafil or L-arginine administration. The present results suggest that urethral relaxation failure, probably related to impairment of the NO/cGMP signalling pathway, rather than bladder contractile dysfunction may be a prominent cause for voiding dysfunction in STZ-induced chronic diabetic rats.

Is coexistent overactive-underactive bladder (with or without detrusor overactivity and underactivity) a real clinical syndrome? ICI-RS 2019

AIMS

Lower urinary tract symptoms (LUTS) can be classified into symptom syndromes based on which symptoms are predominant. Overactive bladder (OAB) syndrome, a storage dysfunction, and underactive bladder (UAB) syndrome, a voiding dysfunction, are common syndromes, which urodynamic tests may show to be caused by detrusor overactivity (DO) and detrusor underactivity (DU), but can also be associated with other urethro-vesical dysfunctions. Sometimes OAB and UAB can coexist in the same patient and, if so, need a specific approach beyond treatment of the single and apparently opposing syndromes.

METHODS

During its 2019 meeting in Bristol, the International Consultation on Incontinence Research Society held a literature review and expert consensus discussion focused on the emerging awareness of the coexisting overactive-underactive bladder (COUB).

RESULTS

The consensus considered whether COUB is the combination of OAB and UAB syndromes, or a real unique clinical syndrome in the same patient, possibly with a common etiology. Definitions, pathophysiology, diagnosis, and treatment were discussed, and high-priority research questions were identified.

CONCLUSIONS

COUB (with or without urodynamic evidence of DO and DU) may be considered a real clinical syndrome, because it differs from single OAB and UAB, and may not be the combination of both syndromes. Urodynamic tests may be necessary in unclear cases or in cases not responding to initial treatment of the most troublesome symptoms. It is pivotal to define the evolution of the syndrome and the characteristic population, and to recognize predictive or phenotyping factors to develop a specific approach and adequate outcome measures.

Clinical characteristics and useful signs to differentiate detrusor underactivity from bladder outlet obstruction in men with non-neurogenic lower urinary tract symptoms

OBJECTIVE

To investigate the clinical characteristics and useful signs to differentiate detrusor underactivity from bladder outlet obstruction in men with non-neurogenic lower urinary tract symptoms.

METHODS

A total of 638 treatment-naive men with non-neurogenic lower urinary tract symptoms who underwent subjective and objective evaluations were reviewed retrospectively. We divided the patients into detrusor underactivity and bladder outlet obstruction groups based on urodynamic findings, and compared parameters obtained from questionnaires and non-invasive tests. Detrusor underactivity was defined as bladder contractility index ≤100 and bladder outlet obstruction index ≤40, whereas bladder outlet obstruction was defined as bladder contractility index >100 and bladder outlet obstruction index >40.

RESULTS

Of 638 patients, 145 (22.7%) had detrusor underactivity and 273 (42.8%) had bladder outlet obstruction. Total international prostate symptom score and international prostate symptom score-voiding subscore were significantly higher in the detrusor underactivity group. There were significant differences in prostate volume, intravesical prostatic protrusion, and all uroflowmetry parameters between the two groups. In multivariate logistic regression analysis, lower intravesical prostatic protrusion (cut-off value 8.2 mm), lower bladder voiding efficiency (cut-off value 70%), and the presence of sawtooth and interrupted waveform on uroflowmetry were significant predictive factors for detrusor underactivity. In particular, the incidence of sawtooth and interrupted waveform was significantly higher in the detrusor underactivity group (80%) than in the bladder outlet obstruction group (12.8%), which showed both high sensitivity (80%) and specificity (87.2%) in differentiating detrusor underactivity from bladder outlet obstruction.

CONCLUSIONS

Sawtooth and interrupted waveform on uroflowmetry can be a useful predictive factor for detrusor underactivity. In addition, lower intravesical prostatic protrusion and bladder voiding efficiency can be of supplementary use.

Medical evaluation and management of male and female voiding dysfunction: a review

A significant workforce shortage of urologists available to serve the US population has been projected to occur over the next decade. Accordingly, much of the management of urologic patients will need to be assumed by other specialties and practitioners. Since primary care physicians are often first evaluate common urologic complaints, it makes sense that these physicians are in an excellent position to intervene in the management of these patients when appropriate. One of the most common complaints in urology is voiding dysfunction. The incidence of voiding dysfunction increases with age, with conservative estimates showing that over 50% of elderly patients suffer. Despite this high prevalence and its negative impact on quality of life, however, few seek or receive treatment, as many do not readily disclose these impactful yet personal symptoms. We sought to summarize the typical presentation, evaluation, assessment and therapeutic options for both male and female patients presenting with voiding dysfunction.

Diagnosis and treatment of urinary and sexual dysfunction in hereditary TTR amyloidosis

Purpose

We aimed to review the current knowledge on the epidemiology, diagnosis, and management of urinary and sexual dysfunction in patients with TTR amyloidosis (ATTR).

Methods

We performed a review of the literature, screening for randomized controlled trials, prospective and retrospective series, position papers, and guidelines on urinary and sexual dysfunction in ATTR patients published in PubMed and Embase.

Results

Lower urinary tract dysfunction is present in up to 83% of patients with ATTR. Voiding symptoms are the most common, reported in 34.8−87.5% of patients, while urinary tract infections are reported in up to 50%. Urinary incontinence is observed in 16.7−37.5% of the ATTR population, mostly due to decreased urethral resistance. Sexual dysfunction affects over 40% of ATTR patients, with erectile dysfunction and sexual arousal disorder being the most common symptoms in male and female patients, respectively. In addition to a thorough clinical examination, invasive pressure-flow urodynamic testing is a cornerstone in the assessment of ATTR lower urinary tract dysfunction. The most common finding is detrusor underactivity and intrinsic sphincter deficiency. Poor bladder compliance can also be observed in patients, due to amyloid deposits on the bladder wall. Urinary tract imaging may be of interest to rule out upper urinary tract deterioration. Given the paucity of data in the ATTR population, treatment should be tailored to the individual patient.

Conclusion

Urinary and sexual dysfunction are highly prevalent in ATTR patients. Comprehensive assessment and multidisciplinary management are keys to avoiding upper urinary tract damage and improving patients’ quality of life.

Predictive factors for recovery of voiding function after transurethral prostate surgery in men with small prostate volume and very low detrusor contractility

OBJECTIVES

Detrusor underactivity (DU) is a common but poorly understood clinical problem. The diagnosis and treatment are difficult and full of uncertainties. There are many overlaps between DU and bladder outlet obstruction (BOO) in men. Prostatic surgery might improve voiding efficiency (VE). This study aims to investigate effectiveness and predictors of voiding function recovery after prostate surgery in patients with DU.

METHODS

Male patients with DU and small total prostate volume (TPV, <40 mL) who had undergone transurethral prostate surgery were retrospectively reviewed over the past two decades. Video-urodynamic studies were performed before and after the operation. The urodynamic parameters were recorded, and change of VE was used to determine treatment outcome. A postoperative VE of ≥50% was considered successful.

RESULTS

A total of 48 patients were included, with a mean age of 74.4 ± 10.0 years. The mean follow-up period was 24.9 ± 30.5 months. At the most recent follow-up, 29 (60.4%) patients had positive results. Among them, 21 (72.4%) patients recovered within 1 month, and only one recovered later than 6 months after the operation. After surgery, the maximum flow rate, voided volume, postvoid residual urine, and VE all showed improvement. Patients with successful outcome had a higher baseline detrusor pressure (p = .029) and greater maximum flow rate (p = .034) than the nonrecovery group. The age and other parameters were not significantly different between recovery and nonrecovery group.

CONCLUSIONS

Patients with DU and small TPV might also benefit from prostatic surgery if they had a higher detrusor pressure and maximum flow rate at baseline.

Spontaneous Activity and the Urinary Bladder

The urinary bladder has two functions: to store urine, when it is relaxed and highly compliant; and void its contents, when intravesical pressure rises due to co-ordinated contraction of detrusor smooth muscle in the bladder wall. Superimposed on this description are two observations: (1) the normal, relaxed bladder develops small transient increases of intravesical pressure, mirrored by local bladder wall movements; (2) pathological, larger pressure variations (detrusor overactivity) can occur that may cause involuntary urine loss and/or detrusor overactivity. Characterisation of these spontaneous contractions is important to understand: how normal bladder compliance is maintained during filling; and the pathophysiology of detrusor overactivity. Consideration of how spontaneous contractions originate should include the structural complexity of the bladder wall. Detrusor smooth muscle layer is overlain by a mucosa, itself a complex structure of urothelium and a lamina propria containing sensory nerves, micro-vasculature, interstitial cells and diffuse muscular elements.Several theories, not mutually exclusive, have been advanced for the origin of spontaneous contractions. These include intrinsic rhythmicity of detrusor muscle; modulation by non-muscular pacemaking cells in the bladder wall; motor input to detrusor by autonomic nerves; regulation of detrusor muscle excitability and contractility by the adjacent mucosa and spontaneous contraction of elements of the lamina propria. This chapter will consider evidence for each theory in both normal and overactive bladder and how their significance may vary during ageing and development. Further understanding of these mechanisms may also identify novel drug targets to ameliorate the clinical consequences of large contractions associated with detrusor overactivity.

Autonomic dysregulation at multiple sites is implicated in age-associated underactive bladder in female mice

AIMS

To evaluate the functional and molecular alterations of contractile and relaxant machinery in the bladder and urethra that lead to the underactive bladder (UAB) in old female mice.

METHODS

Female young (3-months) and old (18-months) C57BL/6 mice were used. Urodynamic was assessed in awake and anaesthetized mice. Electrical-field stimulation (EFS) and concentration-response curves to contractile and relaxing agents in isolated bladders and urethras were performed. Messenger RNA (mRNA) expressions of muscarinic, adrenergic, and transient receptor potential vanilloid-4 (TRPV4), and of the enzymes tyrosine hydroxylase and neuronal nitric oxide synthase (nNOS) were determined. Bladder cyclic adenosine monophosphate (cAMP) levels were measured.

RESULTS

Cystometry in old mice showed incapacity to produce bladder emptying. On filter paper, old mice showed reduced urinary spots. Compared to the young group, bladder contractions induced by EFS and carbachol were lower in old mice. The β₃ -adrenoceptor agonist mirabegron promoted higher bladder relaxation and elevation of cAMP levels in old mice. In old mice urethras, the α_1a -adrenoceptor agonist phenylephrine produced higher contractions, but no differences were found for the NO donor sodium nitroprusside-induced relaxations. In old mice, increased mRNA expressions of β₃ - and α_1a -adrenoceptors in bladder and urethra were found, respectively, whereas the muscarinic M₂ and M₃ receptors and β₂ -adrenoceptors did not change between groups. Reduced mRNA expressions of tyrosine hydroxylase and nNOS were found in old mouse urethras. Additionally, TRPV4 expression was reduced in bladder urothelium from old mice.

CONCLUSION

Age-associated mouse UAB is the result of autonomic dysfunction at multiple levels leading to the less sensitive and overrelaxed bladder, along with urethral hypercontractility.

A Comprehensive Review of Overactive Bladder Pathophysiology: On the Way to Tailored Treatment

CONTEXT

Current literature suggests that several pathophysiological factors and mechanisms might be responsible for the nonspecific symptom complex of overactive bladder (OAB).

OBJECTIVE

To provide a comprehensive analysis of the potential pathophysiology underlying detrusor overactivity (DO) and OAB.

EVIDENCE ACQUISITION

A PubMed-based literature search was conducted in April 2018, to identify randomised controlled trials, prospective and retrospective series, animal model studies, and reviews.

EVIDENCE SYNTHESIS

OAB is a nonspecific storage symptom complex with poorly defined pathophysiology. OAB was historically thought to be caused by DO, which was either "myogenic" (urgency initiated from autonomous contraction of the detrusor muscle) or "neurogenic" (urgency signalled from the central nervous system, which initiates a detrusor contraction). Patients with OAB are often found to not have objective evidence of DO on urodynamic studies; therefore, alternative mechanisms for the development of OAB have been postulated. Increasing evidence on the role of urothelium/suburothelium and bladder afferent signalling arose in the early 2000s, emphasising an afferent "urotheliogenic" hypothesis, namely, that urgency is initiated from the urothelium/suburothelium. The urethra has also recently been regarded as a possible afferent origin of OAB-the "urethrogenic" hypothesis. Several other pathophysiological factors have been implicated, including metabolic syndrome, affective disorders, sex hormone deficiency, urinary microbiota, gastrointestinal functional disorders, and subclinical autonomic nervous system dysfunctions. These various possible mechanisms should be considered as contributing to diagnostic and treatment algorithms.

CONCLUSIONS

There is a temptation to label OAB as "idiopathic" without obvious causation, given the poorly understood nature of its pathophysiology. OAB should be seen as a complex, multifactorial symptom syndrome, resulting from multiple potential pathophysiological mechanisms. Identification of the underlying causes on an individual basis may lead to the definition of OAB phenotypes, paving the way for personalised medical care.

PATIENT SUMMARY

Overactive bladder (OAB) is a storage symptom syndrome with multiple possible causes. Identification of the mechanisms causing a patient to experience OAB symptoms may help tailor treatment to individual patients and improve outcomes.

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.