Intravesical Injection of Botulinum Toxin Type A in Patients with Refractory Overactive Bladder-Results between Young and Elderly Populations, and Factors Associated with Unfavorable Outcomes

Evaluating the Efficacy and Safety of Botulinum Toxin in Treating Overactive Bladder in the Elderly: A Meta-Analysis with Trial Sequential Analysis of Randomized Controlled Trials

Overactive bladder (OAB) significantly impairs quality of life in the elderly. Although the intradetrusor injection of botulinum toxin type A (BoNT-A) is a treatment option, its effects on older adults remain uncertain. This study aimed to evaluate the efficacy and safety of BoNT-A intradetrusor injections in elderly OAB patients through a systematic review and meta-analysis. A comprehensive literature search was conducted using the PubMed, Embase, Cochrane Library, Scopus, and CINAHL databases from inception to 30 May 2024. The primary outcomes were improvements in daily urinary incontinence (UI) episodes and patient-reported outcomes, while the secondary outcomes focused on potential adverse events. Four randomized controlled trials with 803 participants were included. BoNT-A injections significantly reduced daily UI episodes at 4-6 weeks (mean difference [MD]: -3.82; 95% confidence interval [CI]: -6.29 to -1.35) and at 12 weeks (MD: -2.17; 95% CI: -3.22 to -1.12). However, BoNT-A was associated with an increased risk of elevated post-void residual (Risk Difference [RD]: 0.154; 95% CI: 0.058 to 0.251) and urinary tract infection (RD: 0.111; 95% CI: 0.005 to 0.217), with no significant difference observed in the initiation of catheterization or hematuria. Trial sequential analysis confirmed a sufficient sample size and statistical power. In conclusion, while BoNT-A effectively manages OAB in the elderly, careful post-injection monitoring is warranted due to its potential risks.

A Discrete Mathematics Approach for Understanding Risk Factors in Overactive Bladder Treatment

Introduction Discrete mathematics, a branch of mathematics that includes graph theory, combinatorics, and logic, focuses on discrete mathematical structures. Its application in the medical field, particularly in analyzing patterns in patient data and optimizing treatment methods, is invaluable. This study, focusing on post-void residual (PVR) urine following overactive bladder (OAB) treatment, utilized discrete mathematics techniques to analyze PVR and its associated risk factors. Methods A retrospective study was conducted on 128 OAB patients who received intradetrusor onabotulinum toxin A injections between 2020 and 2022. Network graphs based on graph theory were used to analyze correlations between clinical variables, and clustering analysis was performed with PVR as the primary variable. Results The network graph analysis revealed that frailty, daytime frequency, and nocturia episodes were closely related to PVR. Clustering analysis with PVR as the primary variable divided the patients into three groups, suggesting that the group with particularly high frailty (Cluster 1) is at high risk for PVR. Moreover, significant differences in clinical indicators such as age, voiding efficiency, Overactive Bladder Symptom Score, and International Consultation on Incontinence Questionnaire-Short Form were observed in the remaining two clusters (Cluster 0 and 2). Conclusion This study demonstrates the effectiveness of discrete mathematics methods in identifying risk factors for PVR after OAB treatment and in distinguishing clinical subgroups based on patient characteristics. This approach could contribute to the formulation of individualized treatment strategies and the improvement of patient care quality. Further development and clinical application of this methodology are expected in future research.

Current optimal pharmacologic therapies for overactive bladder

INTRODUCTION

Overactive bladder (OAB) is a common syndrome in adults. Current pharmacologic treatment includes antimuscarinic agents and β-3 adrenoceptor agonists. For non-responders to oral medication, intravesical injection of botulinum toxin A (BoNT-A) is an effective option. However, these treatments have potential adverse events and should be cautiously selected for appropriate patients. This review presents the recently published results of clinical trials and studies for patients with OAB and the underlying pathophysiology of OAB. Appropriate medical therapy based on pathophysiology of OAB is also presented.

AREAS COVERED

Literature search from Pubmed from 2001 to 2023 including clinical background, pharmacology, and clinical studies for OAB medications.

EXPERT OPINION

Treatment of OAB syndrome with any antimuscarinic or β-3 adrenoceptor agonist is feasible as a first-line approach. For patients with suboptimal therapeutic effect to full-dose antimuscarinics or mirabegron, combination with both drugs can improve efficacy. Intravesical BoNT-A 100-U injection provides therapeutic effects for refractory OAB. Patients who are refractory to initial pharmacotherapies should be investigated for the underlying pathophysiology; then an appropriate medication can be added, such as an α1-blocker or anti-inflammatory agents. Patient education about behavioral modification and therapies should always be provided with oral medication or BoNT-A injection for OAB patients.

Predictive Factors for High Post-void Residual Volume in Older Females After OnabotulinumA Treatment for Severe Overactive Bladder Using a Machine Learning Model

Introduction Intravesical onabotulinumA injection is actively used for the treatment of overactive bladder (OAB). However, it occasionally results in significant post-void residual urine (PVR) volume, which can lead to complications and can further impair the activities of daily living in older people. Therefore, this study aimed to identify the predictors of a high post-onabotulinumA injection PVR volume in older women with severe OAB. Methods An observational study was conducted on older women who had previously received intravesical onabotulinumA injections to treat OAB between 2020 and 2022. Urodynamic studies and symptom assessments were conducted, and machine learning models, including random forest and support vector machine (SVM) models, were developed using the R code generated by Chat Generative Pre-trained Transformer 4 (ChatGPT, OpenAI, San Francisco, USA). Results Among 128 patients with OAB, 23 (18.0%) had a PVR volume of > 200 mL after receiving onabotulinumA injections. The factors associated with a PVR volume of > 200 mL were investigated using univariate and multivariate analyses. Age, frailty, OAB-wet, daytime frequency, and nocturia were significant predictors. Random forest analysis highlighted daytime frequency, frailty, and voiding efficiency as important factors. An SVM model incorporating daytime frequency, frailty, and voiding efficiency improved PVR volume prediction. Logit(p) estimation yielded an area under the receiver operating characteristic curve of 0.926294.  Conclusion The study found daytime frequency, frailty, and voiding inefficiency to be significant factors associated with a PVR volume of > 200 mL, in older women with severe OAB. Utilizing advanced machine learning techniques and following the guidance of ChatGPT, this research emphasizes the relevance of considering multiple intersecting factors for predicting PVR volume. The findings contribute to our understanding of onabotulinumA injection treatment for OAB and support evidence-based decision-making using readily available information.