Is the beneficial effect of antimuscarinics related to motor or sensory changes in the bladder?

Recent developments in diagnostic ultrasound for lower urinary tract function

Ultrasonography (US) is an essential tool in the clinical management of lower urinary tract dysfunction (LUTD), including lower urinary tract symptoms, overactive bladder, and benign prostatic hyperplasia, in which prostatic volume and post-void residual volume are routinely used to evaluate the pathophysiological characteristics of afflicted patients. US can also be employed to diagnose hydronephrosis and bladder calculus as complications of severe LUTD. Moreover, US is essential for identifying pathophysiological characteristics and surgical indications, predicting disease development and drug efficacy, and monitoring bladder function improvement by means of such parameters as bladder wall thickness, prostatic urethral length, intravesical prostatic protrusion, and prostatic urethral angulation/angle. Herein, I narratively review the recent advances in US approaches for the management of LUTD, especially in adult males.

Presurgical bladder wall thickness is a useful marker to predict the postsurgical improvement of symptoms in patients with pelvic organ prolapse-related overactive bladder

Objectives

Pelvic organ prolapse (POP) is a cause of overactive bladder (OAB), and transvaginal mesh (TVM) surgery can improve the symptoms. Bladder wall thickness (BWT) is a useful and safe marker to evaluate bladder function in urinary disorders. The main purpose of this study is to clarify the relationship between BWT and changes in the OAB symptom score (OABSS) after TVM operation in patients with POP.

Methods

BWT was measured by ultrasonography before and 6 months after surgery at three sites in the bladder: the anterior wall, trigone, and dome. Similarly, the OABSS was evaluated at the time of BWT measurement. Changes induced in BWT at each site and the mean BWT at all sites after TVM surgery were analyzed. Similarly, the relationship between presurgical BWT and the decrease in OABSS was investigated.

Results

TVM surgery improved OABSS in 30 patients (responders; 73.2%), while 11 patients were judged as nonresponders (26.8%). BWT at the anterior bladder wall and dome as well as the mean BWT at all three sites were significantly decreased by TVM surgery (P < .001). Similar trends were identified in OABSS responders; however, all markers showed no significant changes in OABSS nonresponders. All the BWT‐related markers before surgery were significantly lower in OABSS responders than in OABSS nonresponders.

Conclusions

BWT at the bladder anterior wall and dome, but not the trigone, were decreased by TVM surgery. We conclude that presurgical BWT may be a useful marker to predict the improvement in OAB symptoms by TVM surgery in patients with POP‐related OAB.

Comparison of vascularization and overall perfusion of the bladder wall between women with and without overactive bladder syndrome

The pathophysiology of female overactive bleeder syndrome (OAB) remains undetermined. Our aim is to elucidate the role of vacularization and overall perfusion of the bladder wall in women with OAB. Between 2010 and 2016, women with OAB and the asymptomatic controls were enrolled. Women with OAB were treated with tolterodine. Women with OAB (n = 40) had higher vascularization index (0.40 ± 0.57 versus 0.17 ± 0.22, p = 0.003), vascularization-flow index (0.15 ± 0.28 versus 0.05 ± 0.08, p = 0.003) and thicker trigone (0.56 ± 0.13 cm versus 0.47 ± 0.11 cm, p = 0.004), compared with the controls (n = 34). The following optimum cut-off values to predict OAB were determined: (1) vascularization index (%) ≥ 0.16, (2) vascularization-flow index ≥ 0.032, and (3) trigone bladder wall thickness ≥ 0.47 cm with an area under the curve of 0.71, 0.71 and 0.70, respectively. Correlation analysis showed that a significant correlation between urgency and vascularization index/vascularization-flow index (Spearman’s rho = 0.34 and 0.35, respectively, all p < 0.01). However, after 12 weeks of tolterodine treatment, the vascularization index, flow index and vascularization-flow index did not differ between baseline and after treatment. In conclusion, women with OAB have higher vascularization and overall perfusion of the bladder wall, compared women without OAB. However, vascularization and overall perfusion did not change after antimuscarinic treatment.

Detrusor overactivity increases bladder wall thickness in male patients: A urodynamic multicenter cohort study

AIMS

To evaluate the role of Bladder wall thickness (BWT) as a predictor of Detrusor overactivity (DO) in patients with Lower urinary tract symptoms (LUTS)/Benign prostatic enlargement without Bladder Outlet Obstruction.

METHODS

From January 1996 to December 2000, each new patient, aged 45 years or older with LUTS, underwent standard diagnostic assessment, urodynamic studies (cystometry and pressure flow studies), and ultrasound measurements of the bladder wall thickness (BWT) in two centers. In order to exclude the possible effect of benign prostatic obstruction (BPO) on detrusor thickness, patients with a Schaefer class was ≥2 were excluded from the study. The area under the receiver operating characteristics curve (AUC) quantified the predictive accuracy (PA) of BWT for the diagnosis of DO.

RESULTS

Overall 195 patients were enrolled. DO was observed in 98/195 patients (50%). The BWT presented an AUC of 0.70; 95% CI: 0.62-0.77 for the diagnosis of DO. At the best cut-off value of 3.85 mm sensitivity was 73%; specificity was 59%; positive predictive value (64%, PPV). Negative predictive value (69%, NPV).

CONCLUSIONS

Our study firstly showed, how BWT in male patients may be a consequence of DO other than BPO. Our finding, if confirmed in further studies, could limit the accuracy of BWT in patients with DO and BPO.

Assessment of bladder wall thickness in women with overactive bladder

OBJECTIVE

To compare bladder wall thickness (BWT) between female patients with overactive bladder (OAB) and aged-matched healthy controls.

MATERIAL AND METHODS

Thirty-six female patients with OAB and 31 healthy women were enrolled in the present prospective observational study. Qmax and Qave were measured by using uroflowmetry in all of the women in the patient and control groups, and also maximum bladder capacity (MBC), post- void residual urine (PVRU), prevoiding and postvoiding BWT were measured by using transabdominal ultrasound. Lower urinary tract symptoms of the participants were assessed by using Overactive Bladder Version-8 (OAB-V8) and International Consultation on Incontinence Questionnaire-Short Form (ICIQ-SF). All of the data were statistically compared between the patient and control groups. In the patient group, the relationships between parameters were evaluated correlation analysis.

RESULTS

The mean age of the patients and controls were similar (respectively, 45.58±12.35 and 44.21±11.60 years (p=0.68). The mean pre- and post-voiding BWT, OAB-V8 and ICIQ-SF scores of the patients were significantly higher than the controls. In the patient group, the moderate positive correlations between BWT with Qmax (p=0.02) and Qave (p=0.02) were found.

CONCLUSION

This study showed that the BWTs of the female patients with OAB are higher than those of healthy women. Further studies should investigate the changes in BWT of patients with OAB after treatment of OAB.

Bladder wall thickness in women with symptoms of overactive bladder and detrusor overactivity: Results from the randomised, placebo-controlled shrink study

AIMS

Measurement of bladder wall thickness (BWT) by transvaginal ultrasound (TVUS) may be a less invasive method to diagnose overactive bladder (OAB) or detrusor overactivity (DO) and monitor response to therapy. This study assessed whether treatment with solifenacin affects BWT.

METHODS

This was a double-blind, randomised, placebo-controlled, phase 4 study. Adult women with OAB symptoms received solifenacin 5 or 10 mg or placebo once daily for 12 weeks. The co-primary endpoints were change from baseline to Week 12 in TVUS-measured BWT and urinary nerve growth factor. Only results for BWT are presented here.

RESULTS

Overall, 547 patients were randomised, 501 patients had a baseline BWT measurement, and change from baseline could be calculated for 478 patients. Mean BWT at baseline was 5.08 mm (range 2.2-11.1, SD = 1.14) and was normally distributed. A significant reduction in BWT from baseline to 12 weeks versus placebo was observed with solifenacin 5 mg (-0.42 vs. -0.16 mm, P = 0.03), but not with the 10 mg dose or with pooled solifenacin, considered the primary comparison. Both solifenacin doses were associated with improvements in efficacy and patient satisfaction endpoints versus placebo. Solifenacin was well tolerated, with dry mouth being the most common adverse event.

CONCLUSIONS

There was no consistent effect of solifenacin on BWT in women with OAB/DO, despite improvements in efficacy endpoints. This study suggests that routine clinical assessment of BWT with TVUS for monitoring the effects of OAB/DO treatment is not clinically useful. Neurourol. Urodynam. 35:819-825, 2016. © 2015 Wiley Periodicals, Inc.

A comparative study on the efficacy of solifenacin succinate in patients with urinary frequency with or without urgency

Objectives

Patients with overactive bladder (OAB) often have trouble perceiving urgency because of difficulties in distinguishing between urgency and desire to void. Empirical antimuscarinic treatment of patients with frequency only may be reasonable if conservative management has failed. We compared the efficacy of solifenacin in patients with frequency with or without urgency.

Materials and Methods

This multicenter, 12-week, open-label, comparative, non-inferiority clinical trial assessed whether the solifenacin efficacy for frequency without urgency is non-inferior to its efficacy for frequency with urgency. All patients had micturition frequency ≥8 voids/day with or without urgency. Primary efficacy variable: daily frequency change at 12 weeks relative to baseline. Secondary efficacy variables: change at 12 weeks relative to baseline in Patients' Perception of Bladder Condition (PPBC), OAB Symptom Score (OABSS), and Benefit, Satisfaction, Willingness to continue (BSW) questionnaire.

Results

Of the 286 enrolled patients, 240 (83.9%) completed the study (without urgency n = 115; with urgency n = 125). Full dataset analysis revealed that the groups without and with urgency exhibited significant reductions in daily micturition frequency of −2.49±0.35 (mean ± standard error) and −2.63±0.37, respectively. The lower limit of the 95% two-sided CI of the comparison of the two group means was −1.14, which is smaller than the −0.8 margin of clinical equivalence. The two groups did not differ in improvement in PPBC, OABSS, or BSW scores. Both tolerated the treatment well.

Conclusions

It was not possible to verify that the solifenacin efficacy for frequency alone was non-inferior to its efficacy for OAB. Nevertheless, solifenacin tended to be effective for frequency regardless of urgency.

Trial Registration

ClinicalTrials.gov NCT00979472

Review on ultrasound measurement of bladder or detrusor wall thickness in women: techniques, diagnostic utility, and use in clinical trials

PURPOSE

To provide a narrative review of literature evaluating ultrasound techniques for the measurement of bladder wall hypertrophy in women as an alternative to invasive urodynamic assessment for the diagnosis of lower urinary tract symptoms (LUTS).

METHODS

A literature review was performed using PubMed and all paper journals of congress abstracts searching for articles on ultrasound measurement of bladder wall thickness (BWT) or detrusor wall thickness (DWT) published between January 1990 and May 2012. Each study was classified with a level of evidence using the Oxford Centre for Evidence-based Medicine classification (2009).

RESULTS

Ultrasound measurement of bladder wall hypertrophy is not standardised, and techniques vary widely according to anatomical approach, ultrasound frequency and other factors. This review compared transvaginal, translabial/transperineal and suprapubic approaches for ultrasound BWT/DWT measurement. BWT/DWT measurements correlated well with urodynamic diagnoses of detrusor overactivity (DO) using all three ultrasound techniques. BWT values were consistently higher in women with DO than in women with stress incontinence, although threshold values for the differential diagnosis of DO varied between clinical studies (5.0-6.5 mm using transvaginal ultrasound). Few data were available on the use of translabial or suprapubic ultrasound in women. Inter- and intraobserver variability was higher with transperineal and suprapubic ultrasound, and these techniques appear less reliable than transvaginal ultrasound. Studies suggest that BWT is reduced in response to antimuscarinic therapy in women with overactive bladder or DO.

CONCLUSIONS

Data from clinical trials suggest that transvaginal ultrasound measurement of BWT is a reliable method of diagnosing DO in women with LUTS, and BWT decreases during antimuscarinic therapy.

Mirabegron - a selective β3-adrenoreceptor agonist for the treatment of overactive bladder

Overactive bladder is a common condition that significantly impacts overall quality of life. Antimuscarinics are the current main pharmacological option for treatment; however, many patients fail to adhere to therapy due to troublesome side effects. Mirabegron is a new beta-3 adrenoreceptor agonist which causes detrusor smooth muscle relaxation and has been proposed to be effective for treating overactive bladder symptoms. Mirabegron has been shown to be superior to placebo for reducing the mean number of incontinence episodes per 24 hours and the mean number of micturitions per 24 hours. Side effects such as dry mouth were observed at similar or lower rates than those seen for placebo and antimuscarinics. Higher doses of mirabegron were associated with minor increases in pulse rate and mean blood pressure. Mirabegron offers a new alternative for treating overactive bladder in patients for which antimuscarinics are either not tolerated or not appropriate.

Role of botulinum toxin-A in refractory idiopathic overactive bladder patients without detrusor overactivity

BACKGROUND

To evaluate the efficacy of intradetrusor botulinum toxin-A (BTX-A) in idiopathic overactive bladder patients (OAB) refractory to anti-muscarinic therapy, without detrusor overactivity (DOA) on urodynamics.

METHODS

Patients with refractory idiopathic OAB without DOA on urodynamics were prospectively enrolled. Subjects completed a 3-day voiding diary (3-VD), urogenital distress inventory-6 questionnaire (UDI-6) and graded their quality of life on a 10-cm visual analog scale (VAS) prior to study enrollment and at week 12 postinjection. All patients underwent multichannel urodynamics at study enrollment and 12 weeks postinjection. Improvement was analyzed based on 3-VD, UDI-6 questionnaire, VAS scores, and urodynamic parameters at week 12 postinjection compared to study enrollment.

RESULTS

The study included 32 patients. Mean ± SD age was 56 ± 16. There were 27 women and 5 men. Nineteen patients had OAB without incontinence (OAB-dry) and 13 patients had OAB with incontinence (OAB-wet). In OAB-dry patients, mean ± SD urinary frequency dropped from 24 ± 11 to 10 ± 4 by week 12. In OAB-wet patients, mean ± SD urge incontinence episodes dropped from 7.9 ± 5 to 0 ± 2.6 by week 12. Mean UDI-6 and VAS scores improved significantly in both groups by week 12 (P = 0.0001). On comparing urodynamic parameters, OAB-wet patients showed significant decrease in maximum detrusor pressure during the voiding phase at week 12 compared to baseline values (P = 0.02).

CONCLUSIONS

Refractory idiopathic OAB patients without DOA on urodynamics may benefit from intradetrusor BTX-A.

The effect of solifenacin on urethral sphincter morphology

INTRODUCTION AND HYPOTHESIS

The aim of the study was to determine whether a 6-week course of 5 mg of solifenacin succinate used to treat mixed incontinence, produces measurable changes in the appearance of the urethral sphincter.

METHODS

Twenty-six women undergoing treatment for mixed incontinence were recruited from a urogynaecology unit after failing to improve with conservative treatments and bladder drill. All underwent dual channel subtracted cystometry, which showed mixed urodynamic stress incontinence and detrusor overactivity. All patients underwent a 3D transperineal ultrasound before solifenacin therapy was started and after 6 weeks of treatment. The urethral length, width and volume of the smooth muscle and total sphincter volume were compared before and after the treatment.

RESULTS

Clinically, 13 reported no improvement in either stress or urge incontinence. Eight women reported improvement in their urgency symptoms but no benefit in their stress leakage. Four women reported resolution of both stress and urge incontinence. One woman reported worsening of her bladder symptoms. There was no significant change in the urethral length (p = 0.27), width (p = 0.50), volume of smooth muscle (p = 0.87) or total sphincter volume (p = 0.60) before and after treatment with solifenacin.

CONCLUSIONS

A 6-week course of solifenacin resulted in no measurable changes in the appearance of the urethral sphincter.