Intravesical OnabotulinumtoxinA Injection for Overactive Bladder Patients with Frailty, Medical Comorbidities or Prior Lower Urinary Tract Surgery

The Effects of Age, Gender, and Postvoid Residual Volume on Catheterization Rates After Treatment with OnabotulinumtoxinA for Overactive Bladder

Background

Transient increases in postvoid residual urine volume (PVR) requiring clean intermittent catheterization (CIC) have occurred with onabotulinumtoxinA treatment for overactive bladder (OAB).

Objective

To evaluate onabotulinumtoxinA safety and the effect of age, gender, and maximum PVR (PVRmax) on CIC initiation in adults with OAB and urinary incontinence (UI).

Design setting and participants

This was a pooled post hoc analysis of four placebo-controlled, multicenter randomized trials that included adults with idiopathic OAB after first onabotulinumtoxinA treatment (NCT00910845, NCT00910520, NCT01767519, NCT01945489). Patients had at least three urgency UI episodes over 3 d and at least eight micturitions per day, had inadequate management with at least one anticholinergic agent, and were willing to use CIC.

Outcome measurements and statistical analysis

We measured the following outcomes: PVRmax within 12 wk after first treatment; CIC incidence; estimated functional capacity; PVR ratio (PVR/estimated functional capacity).

Results and limitations

Of 1504 patients, 87.7% were women and 88.8% were White. The mean age was 60.5 yr across 10-yr age groups, baseline PVR was 13.8-35.0 ml, and estimated functional capacity was 293.5-475.7 ml. Mean baseline PVR was 21.3 ml overall versus 34.0 ml in the group that started CIC. The CIC incidence was 6.2% for women (range 1.1-8.4%) and 10.5% for men (range 0-14.6%). Higher CIC rates were observed for PVRmax >350 ml (women 91.9%, men 84.6%) in comparison to PVRmax of 201-350 ml (women 32.5%, men 17.4%) and PVRmax <200 ml (women 1.2%, men 1.6%). Overall, 2/1504 patients (both women) were unable to void spontaneously. The mean PVR ratio was highest at week 2. Some subgroups had small sample sizes.

Conclusions

CIC incidence was low overall, was less frequent for women, was rare with PVRmax ≤200 ml, and did not appear to correlate with baseline PVR.

Patient summary

After onabotulinumtoxinA treatment for OAB, patients sometimes insert a catheter to help in emptying their bladder after urinating. In this study, few patients needed a catheter, especially when less urine volume remained after urination.

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.

Overactive Bladder in Frail Older Adults

Overactive bladder (OAB) and frailty are multidimensional syndromes, and the prevalence of both increases with age. Little evidence exists for a direct association between OAB and frailty, but urinary urgency may well be a precursor of frailty in older people. Frail older adults are no less deserving of treatment than fit older adults, and lifestyle, behavioral, and pharmacological interventions remain the primary options for treatment, with some evidence for efficacy. Data on onabotulinumtoxinA therapy or percutaneous tibial nerve stimulation in frail older adults are sparse. Frail older adults are often excluded from drug trials, but evidence is accumulating that antimuscarinics and, to a lesser extent, beta-adrenergic agonists are safe, well-tolerated, and effective in older adults. Cognitive impairment associated with frailty should not be used as justification for avoiding the use of antimuscarinics. More studies are required to better understand the association between OAB and frailty, as both are associated with poor outcomes and may be amenable to intervention. Drug trials for OAB treatments should be encouraged to include frail older adults, as this population is highly affected yet often excluded.

Managing Interstitial Cystitis/Bladder Pain Syndrome in Older Adults

In this review, the current literature regarding pharmacotherapy treatment strategies available for the management of interstitial cystitis/bladder pain syndrome in older adults is addressed. The focus is on those treatments described by the American Urologic Association guidelines, organized according to clinical phenotype. Symptoms at presentation can vary with age, with older adults being more likely to experience nocturia, urinary incontinence, and Hunner's lesions than their younger counterparts. As such, treatment of interstitial cystitis/bladder pain syndrome should follow an individualized multimodal plan based on the patient's unique phenotype(s), starting with the most conservative options and escalating as needed. The side-effect profile and medication interactions should be reviewed, especially when treating older adults, requesting the aid of pharmacists or the primary care physician as needed to safely provide treatment.

Botulinum toxin in low urinary tract disorders - over 30 years of practice (Review)

Botulinum toxin is a substance produced by Clostridium Botulinum and is responsible for human botulism. This substance is a poison, a neurotoxin, but used in limited quantities it can be a cure for some diseases. It is well connected to a large variety of medical applications. The mechanism of action relies on blocking the acetylcholine at the neuromuscular junction, which blocks the transmission of the nervous impulse with secondary flaccid paralysis. In urology, its role in idiopathic overactive bladder and neurogenic bladder is well known. We performed a thorough review using PubMed and other databases, revising the mechanisms of botulinum toxin action in urologic pathology, treatment procedures and other options. Botulinum toxin is a well-studied substance with a large number of applications in medicine. In urologic pathology, overactive bladder and neurogenic bladder are backed by robust studies that support the therapeutic role of this substance. The toxin has multiple effects, such as inhibition of the nerve growth factor, blocking the bladder sensory afferent pathway and apoptotic effect on the prostate tissue, by inhibiting the substance P, altering the nociceptive pathways. Interstitial cystitis and other rare pathologies show promising results, but further studies are needed. The role of botulinum toxin in benign prostatic hyperplasia is still not elucidated.

Can Intradetrusor OnabotulinumtoxinA Injections Alter Heart Function in Patients with Cardiac Arrhythmia?

The prevalence of overactive bladder (OAB) increases with age and can be associated with other co-morbidities, such as cardiac arrhythmia. Unfortunately, commonly used anticholinergic drugs for OAB can affect the cardiovascular system, leading to tachycardia. However, there are no data, which consider the influence of intradetrusor onabotulinumtoxinA injections on heart function in idiopathic OAB patients. The aim of the present study was to evaluate the influence of intradetrusor onabotulinumtoxinA injections on electrocardiogram (ECG) parameters. Additionally, changes in ECG were analyzed in OAB patients without cardiac arrhythmia. Thirty-one patients with cardiac arrhythmia and 31 participants without irregular heart rate (HR) completed the study. ECG measurements were performed in supine positions 2 h before onabotulinumtoxinA injections, 1 h after treatment, and at 2 weeks of follow-up. At week 6, a phone-call survey was conducted to collect data about adverse events. OnabotulinumtoxinA injections were performed with rigid cystoscopy under local anesthesia. We did not observe any clinically significant changes in the analyzed ECG parameters between consecutive measurements. While a slight increase of HR was observed in patients without cardiac arrhythmia, it remained within normal range. Intravesical onabotulinumtoxinA injections are, hence, safe for female patients with cardiac arrhythmia and do not significantly influence changes in ECG.

Frailty and Lower Urinary Tract Symptoms

The incidence of both frailty and lower urinary tract symptoms, including urinary incontinence, overactive bladder, underactive bladder, and benign prostatic hyperplasia, increases with age. However, our understanding of the relationship between frailty and lower urinary tract symptoms, both in terms of pathophysiology and in terms of the evaluation and management of such symptoms, is greatly lacking. This brief review will summarize definitions and measurement tools associated with frailty and will also review the existing state of the literature on frailty and lower urinary tract symptoms in older individuals.

Safety issues associated with using medication to treat overactive bladder

INTRODUCTION

The mainstay of overactive bladder treatment is the use of anticholinergic medication with its common side effects well known. This review focused on three less well-known safety issues when treating OAB. Areas covered: Patients with increased anticholinergic load are at risk of cognitive decline, dementia or even death. The elderly are particularly at risk due to polypharmacy. Botulinum toxin carries the risk of high urinary residuals, urinary tract infection and need to self catheterise. The use of vaginal oestrogens may improve OAB symptoms, but there is concern in those with a history of breast cancer. Studies have shown that the systemic absorption is negligible and does not increase the risk of recurrence. Expert Opinion: Improvement in assessing anticholinergic load is needed with the development of a universal drug scale. To avoid increasing load, Mirabegron or botulinum toxin can be used instead. There is no consensus of the use of prophylactic antibiotics when injecting botulinum toxin and at what residual to initiate self catheterisation. Despite evidence showing that the use of vaginal oestrogens is safe in those with a history of cancer, it is not fully supported by any health body. Further work is needed in those using aromatase inhibitors.