Transcutaneous electrical nerve stimulation and solifenacin succinate versus solifenacin succinate alone for treatment of overactive bladder syndrome: A double-blind randomized controlled study

Efficacy of transcutaneous electrical nerve stimulation combined with mirabegron therapy compared with mirabegron monotherapy for overactive bladder: a prospective randomized controlled study

PURPOSE

The objective was to evaluate the efficacy of transcutaneous electrical nerve stimulation (TENS) combined with mirabegron therapy compared with mirabegron monotherapy in the treatment of female patients with overactive bladder (OAB).

METHODS

In this randomized controlled study, 100 female outpatients with OAB were screened. Among these patients, 86 who met the inclusion criteria were randomly divided into the TENS combined with mirabegron treatment group and mirabegron monotherapy treatment group, with 43 patients in each group. The voiding diary, Overactive Bladder Symptom Score (OABSS), Overactive Bladder Questionnaire Symptom Bother Score (OAB-q SBS), total health-related quality of life (OAB-q HRQoL), and treatment satisfaction-visual analog scale (TS-VAS) score before and after treatment were recorded to evaluate the efficacy of OAB treatment. Seventy-nine of the 86 patients (40 in the TENS plus mirabegron group and 39 in the mirabegron monotherapy group) completed 12 weeks of treatment.

RESULTS

TENS combined with mirabegron therapy was superior to mirabegron monotherapy in improving the primary endpoints, including the daily number of micturition episodes and the daily MVV/micturition and secondary endpoints, including the daily number of urgency episodes, the OABSS, the OAB-q SBS, the HRQoL score and TS-VAS score. There were no statistically significant differences in urgency urinary incontinence and nocturia between the groups. Some minor adverse effects were observed, including muscle pain, local paresthesia and constipation.

CONCLUSIONS

The combination of TENS and mirabegron was more effective than mirabegron alone in the treatment of female patients with OAB.

TRIAL REGISTRATION NUMBER

ChiCTR2400080528 (31.01.2024, retrospectively registered).

Transcutaneous tibial neurostimulation and Solifenacin in urgent incontinence of postmenopausal women

Symptoms of overactive bladder syndrome (OAB), including urinary incontinence, affect a person's quality of life and cause many personal, social and economic problems. Patients were randomly divided into three groups and received transcutaneous tibial nerve stimulation (cTTNS) with fixed parameters or with variable parameters (vTTNS) and Solifenacin drug. The main outcomes including quality of life questionnaire and OAB score and other secondary outcomes were evaluated before and after treatment for 6 weeks. ANOVA test did not show any significant difference between the three groups in quality of life score (p=0.672), OAB symptom score (p=0.159) and incontinence severity (p=0.422). The t-test demonstrated that the post treatment average quality of life score, OAB score, and incontinence severity were significantly different when compared with before treatment in all three groups (p < 0.05). All three methods were effective in treating symptoms of OAB. However, based on the clinical symptoms, cTTNS is recommended as a preferred and acceptable and safe strategy for the treatment of OAB in women over 50 years old.

Treating Lower Urinary Tract Symptoms in Older Adults: Intravesical Options

This article provides an overview of the diagnosis and the treatment of lower urinary tract symptoms in older adults complicated by the neurodegenerative changes in the micturition reflex and further confounded by age-related decline in hepatic and renal clearance raising the propensity of adverse drug reactions. The first-line drug treatment for lower urinary tract symptoms, orally administered antimuscarinics, fails to reach the equilibrium dissociation constant of muscarinic receptors even at their maximum plasma concentration and tends to evoke a half-maximal response at a muscarinic receptor occupancy of just 0.206% in the bladder with a minimal difference from exocrine glands, which raises the adverse drug reaction risk. On the contrary, intravesical antimuscarinics are instilled at concentrations 1000-fold higher than the oral maximum plasma concentration and the equilibrium dissociation constant erects a downhill concentration gradient that drives passive diffusion and achieves a mucosal concentration around ten-fold lower than the instilled concentration for a long-lasting occupation of muscarinic receptors in mucosa and sensory nerves. A high local concentration of antimuscarinics in the bladder triggers alternative mechanisms of action and is supposed to engage retrograde transport to nerve cell bodies for neuroplastic changes that underlie a long-lasting therapeutic effect, while an intrinsically lower systemic uptake of the intravesical route lowers the muscarinic receptor occupancy of exocrine glands to lower the adverse drug reaction relative to the oral route. Thus, the traditional pharmacokinetics and pharmacodynamics of oral treatment are upended by intravesical antimuscarinics to generate a dramatic improvement (~ 76%) noted in a meta-analysis of studies enrolling children with neurogenic lower urinary tract symptoms on the primary endpoint of maximum cystometric bladder capacity as well as the secondary endpoints of filling compliance and uninhibited detrusor contractions. The therapeutic success of intravesical multidose oxybutynin solution or oxybutynin entrapped in the polymer for sustained release in the pediatric population bodes well for patients with lower urinary tract symptoms at the other extreme of the age spectrum. Though generally used to predict oral drug absorption, Lipinski's rule of five can also explain the ten-fold lower systemic uptake from the bladder of positively charged trospium over oxybutynin, a tertiary amine. Chemodenervation by an intradetrusor injection of onabotulinumtoxinA is merited for patients with idiopathic overactive bladder discontinuing oral treatment because of a lack of efficacy. However, age-related peripheral neurodegeneration potentiates the adverse drug reaction risk of urinary retention that motivates the quest of liquid instillation, delivering larger fraction of onabotulinumtoxinA to the mucosa as opposed to muscle by an intradetrusor injection can also probe the neurogenic and myogenic predominance of idiopathic overactive bladder. Overall, the treatment paradigm of lower urinary tract symptoms in older adults should be tailored to individual's overall health status and the risk tolerance for adverse drug reactions.

The Effectiveness in Activating M-Type K+ Current Produced by Solifenacin ([(3R)-1-azabicyclo[2.2.2]octan-3-yl] (1S)-1-phenyl-3,4-dihydro-1H-isoquinoline-2-carboxylate): Independent of Its Antimuscarinic Action

Solifenacin (Vesicare^®, SOL), known to be a member of isoquinolines, is a muscarinic antagonist that has anticholinergic effect, and it has been beneficial in treating urinary incontinence and neurogenic detrusor overactivity. However, the information regarding the effects of SOL on membrane ionic currents is largely uncertain, despite its clinically wide use in patients with those disorders. In this study, the whole-cell current recordings revealed that upon membrane depolarization in pituitary GH₃ cells, the exposure to SOL concentration-dependently increased the amplitude of M-type K⁺ current (I_K(M)) with effective EC₅₀ value of 0.34 μM. The activation time constant of I_K(M) was concurrently shortened in the SOL presence, hence yielding the K_D value of 0.55 μM based on minimal reaction scheme. As cells were exposed to SOL, the steady-state activation curve of I_K(M) was shifted along the voltage axis to the left with no change in the gating charge of the current. Upon an isosceles-triangular ramp pulse, the hysteretic area of I_K(M) was increased by adding SOL. As cells were continually exposed to SOL, further application of acetylcholine (1 μM) failed to modify SOL-stimulated I_K(M); however, subsequent addition of thyrotropin releasing hormone (TRH, 1 μM) was able to counteract SOL-induced increase in I_K(M) amplitude. In cell-attached single-channel current recordings, bath addition of SOL led to an increase in the activity of M-type K⁺ (K_M) channels with no change in the single channel conductance; the mean open time of the channel became lengthened. In whole-cell current-clamp recordings, the SOL application reduced the firing of action potentials (APs) in GH₃ cells; however, either subsequent addition of TRH or linopirdine was able to reverse SOL-mediated decrease in AP firing. In hippocampal mHippoE-14 neurons, the I_K(M) was also stimulated by adding SOL. Altogether, findings from this study disclosed for the first time the effectiveness of SOL in interacting with K_M channels and hence in stimulating I_K(M) in electrically excitable cells, and this noticeable action appears to be independent of its antagonistic activity on the canonical binding to muscarinic receptors expressed in GH₃ or mHippoE-14 cells.

Transcutaneous electrical nerve stimulation as add-on therapy in children receiving anticholinergics and/or mirabegron for refractory daytime urinary incontinence: A retrospective cohort study

AIMS

To investigate if children with daytime urinary incontinence (DUI) and overactive bladder (OAB) refractory to standard urotherapy and medicinal treatment, would experience improvement in symptoms after add-on treatment with transcutaneous electrical nerve stimulation (TENS).

METHODS

Children were retrospectively enrolled from tertiary referral centers at Aarhus and Aalborg University Hospitals. All data were retrieved from the patients' journals. All children were prescribed TENS as an add-on treatment to the highest-tolerable dose of medicinal treatment in a standardized regime of 2 h a day for around 3 months. Primary endpoints were the number of wet days per week (WDPW) and incontinence episodes per day. Effect of treatment was defined as greater or equal to 50% reduction in the frequency of DUI episodes. Secondary endpoints were to establish predictive factors for the effect of treatment using logistic regression.

RESULTS

Seventy-six children diagnosed with DUI and OAB refractory to treatment with standard urotherapy and pharmacological treatment, at the age of 5-16 years were included from February 2017 to February 2020. A reduction in WDPW (from 6.31 [5.86-6.61] to 4.27 [3.45-4.90], p < 0.05) and incontinence episodes per day (from 2.45 [1.98-2.91] to 1.43 [1.07-1.80], p < 0.05) was observed. Twelve patients became completely dry. At 6 months follow-up, seven of the 12 complete responders had relapsed while five remained dry. A history of constipation before TENS was a predictor of poor treatment response (p = 0.016).

CONCLUSIONS

TENS as add-on to anticholinergic treatment seems effective in a number of children with treatment-refractory DUI.