Current pharmacological and surgical treatment of underactive bladder

ABCD1 Gene Mutations: Mechanisms and Management of Adrenomyeloneuropathy

Pathogenic variants in the ABCD1 gene on the X chromosome may result in widely heterogenous phenotypes, including adrenomyeloneuropathy (AMN). Affected males typically present in their third or fourth decade of life with progressive lower limb weakness and spasticity, and may develop signs and symptoms of adrenal insufficiency and/or cerebral demyelination. Heterozygous females may be asymptomatic, but may develop a later-onset and more slowly progressive spastic paraparesis. In this review, we describe the clinical presentation of AMN, as well as its diagnosis and management. The role of rehabilitative therapies and options for management of spasticity are highlighted.

The Dependence of Urinary Bladder Responses on Extracellular Calcium Varies Between Muscarinic, Histamine, 5-HT (Serotonin), Neurokinin, Prostaglandin, and Angiotensin Receptor Activation

With many common bladder diseases arising due to abnormal contractions, a greater understanding of the receptor systems involved may aid the development of future treatments. The aim of this study was to identify any difference in the involvement of extracellular calcium (Ca²⁺) across prominent contractile-mediating receptors within cells lining the bladder. Strips of porcine urothelium and lamina propria were isolated from the urinary bladder dome and mounted in isolated tissue baths containing Krebs-bicarbonate solution, perfused with carbogen gas at 37°C. Tissue contractions, as well as changes to the frequency and amplitude of spontaneous activity were recorded after the addition of muscarinic, histamine, 5-hydroxytryptamine, neurokinin-A, prostaglandin E2, and angiotensin II receptor agonists in the absence and presence of 1 µM nifedipine or nominally zero Ca²⁺ solution. The absence of extracellular Ca²⁺ influx after immersion into nominally zero Ca²⁺ solution, or the addition of nifedipine, significantly inhibited the contractile responses (p < 0.05 for all) after stimulation with carbachol (1 µM), histamine (100 µM), 5-hydroxytryptamine (100 µM), neurokinin-A (300 nM), prostaglandin E2 (10 µM), and angiotensin II (100 nM). On average, Ca²⁺ influx from extracellular sources was responsible for between 20–50% of receptor-mediated contractions. This suggests that although the specific requirement of Ca²⁺ on contractile responses varies depending on the receptor, extracellular Ca²⁺ plays a key role in mediating G protein-coupled receptor contractions of the urothelium and lamina propria.

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.

Impact of detrusor underactivity on the postoperative outcomes after benign prostatic enlargement surgery

INTRODUCTION AND OBJECTIVE

Previous studies suggest that men with detrusor underactivity (DUA) have less symptomatic improvement after prostate surgery than those with normal contractility, but the available data is controversial. We aim to determine the differences in functional outcomes of patients with or without DUA who underwent photovaporization of the prostate (PVP) with GreenLight™180 W XPS.

METHODS

A cohort of patients with lower urinary tract symptoms (LUTS) who underwent PVP between 2012 and 2019 was evaluated. Patients were stratified according to bladder contractility index (BCI). DUA was defined as BCI < 100. Those with normal contractility (BCI = 100-150) were included in Group 1, and those with DUA (BCI < 100) in Group 2. Primary outcomes were symptomatic improvement defined as a reduction ≥ 4 points in the international prostate symptom score (IPSS) and a reduction of at least 1 point in the quality of life (IPSS-QoL). Complications according to the Clavien-Dindo classification were also recorded.

RESULTS

A total of 271 patients who underwent PVP with GreenLight™ and met the inclusion criteria were assessed. Group 1 included 158 patients, while Group 2 included 113 patients. Mean follow-up was 24 months. Patients with normal contractility had a median reduction of 11 points (18.9 ± 8.0 to 7.1 ± 7.0) while patients with DUA had a median reduction of 10 points (19.3 ± 6.9 to 8.6 ± 8.4) in IPSS score; these differences were not statistically significant (p = .20). Patients in Group 1 had a 1.92 higher chance of QoL improvement (OR, 1.92; 90% CI, 1.10-3.37), compared to those in Group 2. Failure to void after PVP was most frequently reported in DUA patients (OR, 2.36; 90% CI, 1.26-4.43). Sociodemographic characteristics, intraoperative complications, conversion rates, hospital stay, and urinary catheterization time were similar between groups.

CONCLUSIONS

Patients with LUTS, regardless of their BCI, improved their symptoms after PVP according to the IPSS. However, patients with DUA were more likely not to improve their QoL after the procedure and had a higher chance of failure to void in the immediate postoperative period. An appropriate counseling process with the patient discussing possible outcomes based on these findings should be encouraged.

Postoperative interventions for preventing bladder dysfunction after radical hysterectomy in women with early-stage cervical cancer

BACKGROUND

Bladder dysfunction is a common complication following radical hysterectomy, caused by the damage to pelvic autonomic nerves that innervate the muscles of the bladder, urethral sphincter, and pelvic floor fasciae. Bladder dysfunction increases the rates of urinary tract infection, hospital visits or admission, and patient dissatisfaction. In addition, bladder dysfunction can also negatively impact patient quality of life (QoL). Several postoperative interventions have been proposed to prevent bladder dysfunction following radical hysterectomy. To our knowledge, there has been no systematic review evaluating the effectiveness and safety of these interventions for preventing bladder dysfunction following radical hysterectomy in women with cervical cancer.

OBJECTIVES

To evaluate the effectiveness and safety of postoperative interventions for preventing bladder dysfunction following radical hysterectomy in women with early-stage cervical cancer (stage IA2 to IIA2).

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL; 2020, Issue 4) in the Cochrane Library, MEDLINE via Ovid (1946 to April week 2, 2020), and Embase via Ovid (1980 to 2020, week 16). We also checked registers of clinical trials, grey literature, conference reports, and citation lists of included studies.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) evaluating the effectiveness and safety of any type of postoperative interventions for preventing bladder dysfunction following a radical hysterectomy in women with stage IA2 to IIA2 cervical cancer.

DATA COLLECTION AND ANALYSIS

Two review authors independently selected potentially relevant RCTs, extracted data, assessed risk of bias, compared results, and made judgments on the quality and certainty of the evidence. We resolved any disagreements through discussion or consultation with a third review author. Outcomes of interest consisted of spontaneous voiding recovery one week after the operation, quality of life (QoL), adverse events, post-void residual urine volume one month after the operation, urinary tract infection over the one month following the operation, and subjective urinary symptoms.

MAIN RESULTS

We identified 1464 records as a result of the search (excluding duplicates). Of the 20 records that potentially met the review criteria, we included five reports of four studies. Most of the studies had unclear risks of selection and reporting biases. Of the four studies, one compared bethanechol versus placebo and three studies compared suprapubic catheterisation with intermittent self-catheterisation. We identified two ongoing studies. Bethanechol versus placebo The study reported no information on the rate of spontaneous voiding recovery at one week following the operation, QoL, adverse events, urinary tract infection in the first month after surgery, and subjective urinary symptoms for this comparison. The volume of post-void residual urine, assessed at one month after surgery, among women receiving bethanechol was lower than those in the placebo group (mean difference (MD) -37.4 mL, 95% confidence interval (CI) -60.35 to -14.45; one study, 39 participants; very-low certainty evidence). Suprapubic catheterisation versus intermittent self-catheterisation The studies reported no information on the rate of spontaneous voiding recovery at one week and post-void residual urine volume at one month following the operation for this comparison. There was no difference in risks of acute complication (risk ratio (RR) 0.77, 95% CI 0.24 to 2.49; one study, 71 participants; very low certainty evidence) and urinary tract infections during the first month after surgery (RR 0.77, 95% CI 0.53 to 1.13; two studies, 95 participants; very- low certainty evidence) between participants who underwent suprapubic catheterisation and those who underwent intermittent self-catheterisation. Available data were insufficient to calculate the relative measures of the effect of interventions on QoL and subjective urinary symptoms.

AUTHORS' CONCLUSIONS

None of the included studies reported rate of spontaneous voiding recovery one week after surgery, time to a post-void residual volume of urine of 50 mL or less, or post-void residual urine volume at 6 and 12 months after surgery, all of which are important outcomes for assessing postoperative bladder dysfunction. Limited evidence suggested that bethanechol may minimise the risk of bladder dysfunction after radical hysterectomy by lowering post-void residual urine volume. The certainty of this evidence, however, was very low. The effectiveness of different types of postoperative urinary catheterisation (suprapubic and intermittent self-catheterisation) remain unproven.

Excitatory effect of acotiamide on rat and human bladder: Implications for underactive bladder treatment

OBJECTIVE

To evaluate whether approved gastroprokinetic agent, acotiamide exerts a direct excitatory effect on bladder to help explain the reported meaningful reduction of post-void residual urine volume (PVR) in detrusor underactivity (DU) patients after thrice daily oral intake of acotiamide 100 mg for 2 weeks.

METHODS

Effect of acotiamide [1-16 μM] was assessed on nerve-mediated contractions evoked by electrical field stimulation (EFS) for 5 s with 5 ms pulse trains of 10 V in longitudinal, mucosa intact rat and human bladder strips to construct frequency response curve (1-32 Hz) and repeat 10 Hz stimulation at 60s interval. Effect of acotiamide 2 μM on spontaneous and carbachol evoked contractions was also assessed.

RESULTS

Acotiamide 2 μM significantly enhanced the Atropine and Tetrodotoxin (TTX)-sensitive EFS evoked contractions of rat and human bladder at 8-32 Hz (Two-way ANOVA followed Sidak's multiple comparison; *p < 0.01) and on repeat 10 Hz stimulation (Paired Student's t-test; *p < 0.05), while producing a modest effect on the spontaneous contractions and a negligible effect on the carbachol evoked contractions.

CONCLUSIONS

Enhancement of TTX-sensitive evoked contractions of rat and human bladder by acotiamide is consistent with the enhancement of excitatory neuro-effector transmission mainly through prejunctional mechanisms. Findings highlight immense therapeutic potential of antimuscarinics with low M3 receptor affinity like acotiamide in Underactive bladder (UAB)/DU treatment.

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.

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.

Underactive bladder: A review of the current treatment concepts

According to the International Continence Society standardization reports, underactive bladder (UAB) is a decrease in detrusor contraction and/or shortening of the contraction time, resulting in an incomplete and/or prolongation of the bladder emptying within the normal time frame. It has been indicated that idiopathic, neurogenic, myogenic, and iatrogenic factors play a role in the etiology. To make a diagnosis, it is absolutely necessary to perform a pressure-flow study. Treatment alternatives are generally based on the evacuation of the lower urinary tract, independent of the etiology. UAB treatments are listed under the headings of conservative methods and clean intermittent catheterization, pharmacotherapy (alpha-blockers, cholinesterase inhibitors, muscarinic agonists, prostaglandin E2, and acotiamide), surgical treatments (sacral nerve stimulation-electrical stimulation, injections into the external sphincter, surgeries to be performed for bladder outlet obstruction, reduction cystoplasty, and latissimus dorsi detrusor myoplasty), and stem cell and gene therapies. It is still controversial whether satisfactory success is achieved in the treatment of patients with UAB. Owing to the better understanding of the pathophysiology, future developments in the pharmaceutical industry, gene therapy, and biomedical applications are expected to close the gap in the treatment.