The challenge of overactive bladder therapy: alternative to antimuscarinic agents

Treatment for overactive bladder: A meta-analysis of transcutaneous tibial nerve stimulation versus percutaneous tibial nerve stimulation

BACKGROUND

We aim to compare the safety and effectiveness of transcutaneous tibial nerve stimulation (TTNS) versus percutaneous tibial nerve stimulation (PTNS) in treating overactive bladder.

METHODS

A systematical search on PubMed, Embase, clinicalTrial.gov, and Cochrane Library Central Register of Controlled Trials from January 1, 1999 to November 1, 2020 was performed. The primary outcomes were the changes in a 3-day voiding diary. Quality of life scores were also evaluated. Review Manager 5.3 (Cochrane Collaboration, Oxford, UK) was applied to conduct all statistical analyses.

RESULTS

A total of 4 trials (2 randomized controlled trials, 1 retrospective study, and 1 before-after study) with 142 patients were eventually enrolled. Compared with PTNS, TTNS had a similar performance in the voiding frequency in 24 hours (mean difference [MD] = -0.65, 95% confidence interval [CI]: -1.35 to 0.05, P = .07), the number of urgency episodes in 24 hours (MD = 0.13, 95% CI: -0.36 to 0.62, P = .60), the number of incontinence episodes in 24 hours (MD = 0.01, 95% CI: -0.13 to 0.14, P = .93), as well as in the nocturia frequency (MD = -0.14, 95% CI: -0.52 to 0.24, P = .47). Moreover, comparable results were observed regarding HRQL scores (P = .23) and incontinence quality of life scores (P = .10) in both groups. The total complication rate in the current study was 2.1% (3/142). No adverse events were identified in the TTNS group.

CONCLUSION

Current data supported that TTNS is as effective as PTNS for the treatment of overactive bladder, moreover, with no reported adverse events. However, the evidence is low-grade and well-designed prospective studies with a large sample size are warranted to verify our findings.

Evaluation of autonomic nervous system function in children with overactive bladder syndrome

PURPOSE

We aimed to evaluate the autonomic nervous system activity in children with overactive bladder (OAB) syndrome.

METHODS

Included in the study were 40 children with overactive bladder and 28 healthy controls. Autonomic tests were performed on all participants, including heart rate interval variation (RRIV), heart rate response to valsalva maneuver, and sympathetic skin response (SSR).

RESULTS

Mean valsalva rates in the overactive bladder and control groups were 1.53 ± 0.29 and 1.30 ± 0.18, respectively, a statistically significant difference (P < 0.001). Also significantly different were deep breathing RRIV values of the study and control groups: 56.65 ± 14.66 and 47.92 ± 10.15, respectively (P = 0.008). No statistical differences were found in SSR when OAB patients were compared with controls (P > 0.05).

CONCLUSIONS

This study demonstrated a parasympathetic hyperactivity in children with OAB, results suggesting a dysfunction in their autonomic nervous systems. Neurourol. Urodynam. 36:673-676, 2017. © 2016 Wiley Periodicals, Inc.

Involvement of 5-HT3 receptors in pudendal inhibition of bladder overactivity in cats

In the present study, the role of 5-HT3 receptors in pudendal neuromodulation of bladder activity and its interaction with opioid receptors were investigated in anesthetized cats. The bladder was distended with either saline to induce normal bladder activity or with 0.25% acetic acid (AA) to induce bladder overactivity. Pudendal afferent nerves were activated by 5-Hz stimulation at multiples of the threshold (T) intensity for the induction of anal twitching. AA irritation significantly reduced bladder capacity to 16.5 ± 3.3% of saline control capacity, whereas pudendal nerve stimulation (PNS) at 1.5-2 and 3-4 T restored the capacity to 82.0 ± 12% (P = 0.0001) and 98.6 ± 15% (P < 0.0001), respectively. Cumulative doses (1-3 mg/kg iv) of ondansetron, a 5-HT3 receptor antagonist, eliminated low-intensity (1.5-2 T) PNS inhibition and reduced high-intensity (3-4 T) PNS inhibition of bladder overactivity. During saline distention, PNS at 1.5-2 and 3-4 T significantly increased bladder capacity to 173.2 ± 26.4% (P = 0.036) and 193.2 ± 22.5% (P = 0.008), respectively, of saline control capacity, but ondansetron (0.003-3 mg/kg iv) did not alter PNS inhibition. Ondansetron (0.1-3 mg/kg) also significantly (P < 0.05) increased control bladder capacity (50-200%) during either AA irritation or saline distention. In both conditions, the effects of low- and high-intensity PNS were not significantly different. After ondansetron (3 mg/kg) treatment, naloxone (1 mg/kg iv) significantly (P < 0.05) decreased control bladder capacity (40-70%) during either AA irritation or saline distention but failed to affect PNS inhibition. This study revealed that activation of 5-HT3 receptors has a role in PNS inhibition of bladder overactivity. It also indicated that 5-HT3 receptor antagonists might be useful for the treatment of overactive bladder symptoms.

Inhibition of bladder overactivity by a combination of tibial neuromodulation and tramadol treatment in cats

Our recent study in cats revealed that inhibition of bladder overactivity by tibial nerve stimulation (TNS) depends on the activation of opioid receptors. TNS is a minimally invasive treatment for overactive bladder (OAB), but its efficacy is low. Tramadol (an opioid receptor agonist) is effective in treating OAB but elicits significant adverse effects. This study was to determine if a low dose of tramadol (expected to produce fewer adverse effects) can enhance the TNS inhibition of bladder overactivity. Bladder overactivity was induced in α-chloralose-anesthetized cats by an intravesical infusion of 0.25% acetic acid (AA) during repeated cystometrograms (CMGs). TNS (5 Hz) at two to four times the threshold intensity for inducing toe movement was applied during CMGs before and after tramadol (0.3-7 mg/kg iv) to examine the interaction between the two treatments. AA irritation significantly reduced bladder capacity to 24.8 ± 3.3% of the capacity measured during saline infusion. TNS alone reversibly inhibited bladder overactivity and significantly increased bladder capacity to 50-60% of the saline control capacity. Tramadol administered alone in low doses (0.3-1 mg/kg) did not significantly change bladder capacity, whereas larger doses (3-7 mg/kg) increased bladder capacity (50-60%). TNS in combination with tramadol (3-7 mg/kg) completely reversed the effect of AA. Tramadol also unmasked a prolonged (>2 h) TNS inhibition of bladder overactivity that persisted after termination of the stimulation. The results suggest a novel treatment strategy for OAB by combining tibial neuromodulation with a low dose of tramadol, which is minimally invasive with a potentially high efficacy and fewer adverse effects.

Comparison between imipramine and imipramine combined with pseudoephedrine in 5-12-year-old children with uncomplicated enuresis: a double-blind clinical trial

OBJECTIVE

Monosymptomatic nocturnal enuresis is a common entity, with a prevalence of 10% at the age of 7 years. For its primary treatment, we compared the effect of combination medical therapy (imipramine with pseudoephedrine) with imipramine alone.

MATERIALS AND METHODS

In this one-center prospective double-blind clinical trial, 100 school-age children (age range 5-12 years) were enrolled. They were divided into two groups, comparable in terms of age and other demographic factors: (A) adjusted doses of a combination of imipramine with pseudoephedrine, and (B) imipramine with placebo were administered. Improvement was defined as less than 2 wet nights per week.

RESULTS

Four weeks after drug withdrawal, the response rate was 74% in group A in comparison to 52% in group B, this difference being statistically significant. There was a recurrence of enuresis in both groups during the 4 weeks after treatment was discontinued (10% increase in group A and 8% increase in group B).

CONCLUSION

The additive pharmacologic effects of imipramine with pseudoephedrine for the treatment of monosymptomatic nocturnal enuresis in children were well tolerated, and gave significantly faster results than single drug therapy using imipramine. The moderate-to-high recurrence rate following discontinuation of medical treatment indicates the need for a longer term study involving more cases.

Trospium chloride treatment of overactive bladder

OBJECTIVE

To review the pharmacology, pharmacokinetics, safety, and clinical application of trospium chloride for the management of overactive bladder (OAB).

DATA SOURCES

Clinical literature including both primary sources and review articles was accessed through MEDLINE, International Pharmaceutical Abstracts, and Cochrane databases from 1980 through January 8, 2009. Search terms included overactive bladder, urge urinary incontinence, muscarinic receptor antagonists, and urinary frequency. Further data sources were identified from bibliographies of selected articles.

STUDY SELECTION AND DATA EXTRACTION

Basic pharmacology data were extracted from animal studies and pharmacokinetic data were gathered from human studies. Multicenter, parallel, randomized, double-blind, placebo-controlled studies were included to describe the efficacy and adverse effects of trospium.

DATA SYNTHESIS

Trospium chloride is an antimuscarinic agent indicated for the treatment of OAB with symptoms of urge urinary incontinence, urgency, and urinary frequency. Trospium has 3 chemical and pharmacokinetic properties unique among antimuscarinic agents: it is a positively charged quaternary ammonium compound with minimal central nervous system penetration; it is not metabolized by the cytochrome P450 system, resulting in a lower tendency for drug interactions; and it is excreted mainly unchanged in the urine as the active parent compound, providing local activity to achieve early onset of clinical effect and prolonged efficacy. In two 12-week, randomized, placebo-controlled clinical studies in adults with OAB, trospium 20 mg twice daily was more effective than placebo in reducing the number of micturitions per 24 hours, reducing the number of urge incontinence episodes per week, and increasing the volume of urine voided per micturition. Placebo-controlled trials report efficacy with trospium in treatment of OAB; comparative trials with other anticholinergic agents are limited. Current therapy of OAB consists primarily of anticholinergic drugs such as oxybutynin, which are associated with therapy-limiting adverse effects. Because the prevalence of OAB is greatest among the elderly, safety considerations regarding renal function must be noted, with dosage adjustment required in patients with severe renal impairment.

CONCLUSIONS

Whether the pharmacodynamic properties of trospium make it superior to other therapies will require considerable additional experience with the drug. For now, it appears to be a feasible alternative for patients who cannot tolerate oxybutynin.

Effect of eviprostat on bladder overactivity in an experimental cystitis rat model

OBJECTIVE

The purpose of this study was to investigate the effects of eviprostat, a phytotherapeutic drug, on bladder overactivity and inflammation in a cyclophosphamide (CYP)-induced cystitis rat model.

METHODS

Female Sprague-Dawley rats received a single intraperitoneal injection of CYP (200 mg/kg) or saline. After the CYP injection, eviprostat (9, 18 or 54 mg/kg per day) or a vehicle was orally given twice each day. Four days after the CYP injection, bladder function was evaluated by cystometrograms under urethane anesthesia. In a separate group, bladder inflammation was compared between the eviprostat- or vehicle-treated animals. Furthermore, the effects of eviprostat on carbachol-induced muscle contraction were evaluated by an in vitro experiment.

RESULTS

The intercontraction interval (ICI) significantly decreased in the CYP-injected rats in comparison to the saline-injected rats. In the CYP-injected group, 18 and 54 mg/kg per day of eviprostat treatment significantly increased the ICI, but did not change the maximum voiding pressure in comparison to the vehicle treatment. In the saline-injected group, no significant changes of any parameters in the cystometrograms were observed between the eviprostat- and vehicle-treated groups. CYP-induced bladder inflammation tended to be lower in the eviprostat-treated group in comparison to the vehicle-treated group. An in vitro experiment revealed that eviprostat failed to inhibit carbachol-induced muscle contraction.

CONCLUSION

The oral administration of eviprostat suppressed CYP-induced bladder overactivity. The effects of eviprostat on the micturition reflex may be irrespective of antimuscarinic action. The present findings raise the possibility that eviprostat could be an effective treatment for bladder overactivity associated with inflammation.

Effective treatment of neurogenic detrusor dysfunction by combined high-dosed antimuscarinics without increased side-effects

OBJECTIVES

Patients with neurogenic bladder dysfunction demonstrate an insufficient treatment outcome under dosage-escalated monotherapy. With the objectives of continence and normalised bladder pressure, safe and tolerable non-invasive treatment alternatives were evaluated by using combined antimuscarinics.

METHODS

Twenty-seven patients who were previously registered in a doubled antimuscarinics study were enrolled in this study. The patients demonstrated urodynamic-proven neurogenic bladder dysfunction with incontinence, reduced bladder capacity, and increased intravesical pressure, resulting from spinal cord injury (n=21); spinal cord dysplasia (myelomeningocele; n=3); multiple sclerosis (n=2), and viral encephalomyelitis (n=1). On the basis of the initial study treatment, they were allocated into three groups and treated with two antimuscarinics. Before enrollment, at 4 wk, and at 6 mo, patients underwent urodynamics and recorded bladder diaries, including side-effects.

RESULTS

In all three groups, significant changes were noted at the 4-wk follow-up. Incontinence events decreased from an average of 7 to 1 event per day. The average median bladder capacity (180-393 ml) and reflex volume (125-335 ml) increased; detrusor compliance also improved (average, 15-33 ml/cm H2O). Seven patients reported side-effects; two discontinued the successful treatment. Two other patients did not reach satisfactory amelioration of the detrusor dysfunction.

CONCLUSION

With combined high-dosage antimuscarinic medications, 85% of the patients who previously demonstrated unsatisfactory outcome with dosage-escalated monotherapy were treated successfully. The appearance of side-effects was comparable to that of normal-dosed antimuscarinics. Further studies are required to investigate the long-term pharmacological and physiological background of our findings.