Vitamin D levels and the risk of overactive bladder: a systematic review and meta-analysis

CONTEXT

Overactive bladder is treated mainly with behavioral and drug therapy, and symptoms of urinary frequency and incontinence are challenging to eliminate. There is thus a continuous unmet need for new drugs with a substitution effect mechanism.

OBJECTIVE

It not known whether vitamin D deficiency can lead to overactive bladder or urinary incontinence or whether vitamin D supplementation alleviates bladder symptoms. This comprehensive systematic review with meta-analysis was conducted to determine whether overactive bladder is associated with vitamin D deficiency.

DATA SOURCES

The PubMed and Cochrane Library databases were searched systematically up to July 3, 2022.

DATA EXTRACTION

Initially, 706 articles were identified in the literature search, of which 13 were included in the systematic review: 4 randomized controlled trials, 3 cohort studies, 3 cross-sectional studies, and 3 case-control studies.

DATA ANALYSIS

An increased risk of overactive bladder and urinary incontinence was observed with vitamin D deficiency (odds ratio [OR] = 4.46; 95%CI, 1.03-19.33; P = 0.046 and OR = 1.30; 95%CI, 1.01-1.66; P = 0.036, respectively). Vitamin D levels were relatively low in patients with overactive bladder or urinary incontinence (SMD = -0.33; 95%CI, -0.61 to -0.06, P = 0.019). On the basis of existing data, the risk of urinary incontinence was reduced by 66% after vitamin D supplementation (OR = 0.34; 95%CI, 0.18-0.66; P = 0.001). Egger test was conducted to assess publication bias, and the results were tested for robustness using a sensitivity analysis.

CONCLUSIONS

Vitamin D deficiency increases the risk of overactive bladder and urinary incontinence, and vitamin D supplementation reduces the risk of urinary incontinence. The development of new strategies to prevent or alleviate bladder symptoms is crucial. Vitamin D supplementation may be gaining recognition as an effective strategy for prevention or alleviation of bladder symptoms such as overactive bladder and incontinence.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO registration no. CRD42022351443.

Treating Neurogenic Lower Urinary Tract Dysfunction in Chronic Spinal Cord Injury Patients-When Intravesical Botox Injection or Urethral Botox Injection Are Indicated

Lower urinary tract symptoms (LUTS), such as urgency, urinary incontinence, and/or difficulty voiding, hamper the quality of life (QoL) of patients with spinal cord injury (SCI). If not managed adequately, urological complications, such as urinary tract infection or renal function deterioration, may further deteriorate the patient's QoL. Botulinum toxin A (BoNT-A) injection within the detrusor muscle or urethral sphincter yields satisfactory therapeutic effects for treating urinary incontinence or facilitating efficient voiding; however, adverse effects inevitably follow its therapeutic efficacy. It is important to weigh the merits and demerits of BoNT-A injection for LUTS and provide an optimal management strategy for SCI patients. This paper summarizes different aspects of the application of BoNT-A injection for lower urinary tract dysfunctions in SCI patients and provides an overview of the benefits and drawbacks of this treatment.

Clinical Application of Botulinum Neurotoxin in Lower-Urinary-Tract Diseases and Dysfunctions: Where Are We Now and What More Can We Do?

Botulinum toxin A (Botox) had been considered a promising drug that has an effect on functional disorders of the lower urinary tract. Because Botox exhibits anti-inflammatory and antispasmodic effects, Botox injection into the bladder can decrease detrusor contractility, reduce bladder hypersensitivity, and eliminate painful sensations. Injecting Botox into the bladder outlet can relax the hyperactivity of the bladder neck, and of the urethral smooth and striated muscles. Based on these therapeutic effects, Botox has been widely applied to treat lower-urinary-tract dysfunctions (LUTDs) such as overactive bladder and neurogenic detrusor overactivity. However, this treatment has not been licensed for use in other LUTDs such as interstitial cystitis, voiding dysfunction due to benign prostatic hyperplasia in men, and dysfunctional voiding in women. Botox has also not been approved for the treatment of children with overactive bladder and dysfunctional voiding; in patients with spinal cord injuries with detrusor sphincter dyssynergia and autonomic dysreflexia; or for poorly relaxed external sphincter in non-neurogenic patients. This article reviews the current knowledge regarding Botox treatment for LUTDs and discusses the potential clinical applications of Botox, as well as work that can be conducted in the future.

Frontiers in the Clinical Applications of Botulinum Toxin A as Treatment for Neurogenic Lower Urinary Tract Dysfunction

Patients with neurogenic lower urinary tract dysfunction (NLUTD) experience urinary incontinence with or without difficult urination, which might promote recurrent urinary tract infection (UTI) and exacerbate upper urinary tract function. Nonetheless, appropriate bladder management has been shown to reduce urological complications and improve quality of life. In addition to pharmacological therapy and surgical intervention, botulinum toxin A (BoNT-A) has been widely utilized in NLUTD. The therapeutic efficacy of detrusor BoNT-A injections for neurogenic detrusor overactivity due to spinal cord injury (SCI), multiple sclerosis, or other central nervous system lesions, such as cerebrovascular accident, Parkinson disease, early dementia, and pediatric NLUTD due to myelomeningocele, has been well established, with repeated BoNT-A injections every 6 to 9 months being necessary to maintain its therapeutic effects. Urethral BoNT-A injection can decrease urethral sphincter resistance and facilitate efficient voiding in patients with NLUTD who wish to preserve self-voiding. Detrusor BoNT-A injection can also decrease the occurrence of autonomic dysreflexia in patients with SCI, even after failed augmentation enterocystoplasty, with additional benefits including reduced UTI episodes and preserved renal function with repeated injections. However, this treatment does have some side effects. Complete informed consent for BoNT-A injection therapy with full disclosure of its potential complications should therefore be obtained before this procedure is undertaken.

Will repeated botulinum toxin A improve detrusor overactivity and bladder compliance in patients with chronic spinal cord injury?

Chronic spinal cord injury (SCI) can induce neurogenic detrusor overactivity (NDO), leading to urinary incontinence and renal damage due to low bladder compliance and high detrusor pressure during the storage and voiding of urine. In 2011, Botox^® (onabotulinumtoxinA, botulinum neurotoxin serotype A [BoNT-A]) was approved by the Food and Drug Administration for the treatment of NDO. Intradetrusor injection of BoNT-A has been shown to have clinical utility for the treatment of urinary incontinence, with consequent improvements in quality of life for patients. In the past 20 years, this treatment has been shown to be an effective treatment for patients with SCI refractory to antimuscarinic medication. The present review focused on publications in MEDLINE/PubMed relating to botulinum toxin to evaluate the treatment outcomes of repeated injection of BoNT-A, the mechanisms of action, results of clinical and urodynamic studies, and adverse effects.

Current and potential urological applications of botulinum toxin A

Botulinum toxin subtype A (BoNT-A) is a potent neurotoxin that can selectively modulate neurotransmitter release from nerve endings, resulting in muscular paralysis. BoNT-A might also act on sensory nerves, and have an anti-inflammatory effect. In the first urological use of BoNT-A, injection into the urethral sphincters of patients with detrusor-sphincter dyssynergia resulted in a reduction of urethral resistance and improved voiding efficiency. Subsequently, intravesical BoNT-A injections have received regulatory approval for treatment of neurogenic detrusor overactivity owing to spinal cord lesions or multiple sclerosis, and idiopathic overactive bladder in adults. BoNT-A has also been widely used to treat patients with the off-label indications of neurogenic or non-neurogenic voiding dysfunction and male lower urinary tract symptoms owing to BPH and bladder-neck dysfunction. Other indications for which urologists have applied BoNT-A injections include interstitial cystitis/bladder pain syndrome, bladder oversensitivity and chronic pelvic pain syndrome. BoNT-A is currently delivered as an intravesical injection; however, use of liposome encapsulated formulations is also beginning to show some therapeutic potential.

Patient experience and satisfaction with Onabotulinumtoxin A for refractory overactive bladder

OBJECTIVE

To evaluate the patient experience of our dedicated botulinum toxin A (BTX-A) service using a validated patient-reported experience measure (PREM) and assess patient-reported satisfaction with treatment.

MATERIALS AND METHODS

The first 100 patients who underwent BTX-A treatment for refractory idiopathic detrusor overactivity (IDO) in our institution were contacted for telephone interview. They had all been assessed, injected and followed up in a dedicated BTX-A clinic. Patients were asked to complete a validated PREM - the Client Satisfaction Questionnaire (CSQ-8) - as well as a questionnaire developed in our department to assess satisfaction with the results of the treatment. Most patients received 200 U OnabotulinumtoxinA (Botox(®) ) via an outpatient local anaesthetic flexible cystoscopy technique.

RESULTS

Complete data was available for 72 patients. In all, 49 patients were continuing to receive BTX-A treatment while 23 had opted for no further injections. The overall mean (sd) CSQ-8 satisfaction score was 38.3 (3.3), indicating a high level of patient satisfaction with the service offered in our institution. There was a significant difference in total satisfaction scores between those still receiving BTX-A (mean score 29.8) and those who have discontinued treatment (mean score 25.1) (P < 0.01). Overall patient satisfaction with the result of the treatment was high with an overall mean (sd) score of 8.6 (2.0) on a visual analogue scale. Of those who had discontinued BTX-A, most were either using conservative measures only (44%) or had recommenced anticholinergic medications.

CONCLUSION

Overall patient satisfaction with the dedicated BTX-A service offered in our institution is high and can result in a positive patient experience. The use of PREMs are advocated in order to fully capture the patient's views of the quality of services and treatments they receive.

Use of botulinum toxin in individuals with neurogenic detrusor overactivity: state of the art review

BACKGROUND

Botulinum neurotoxin (BoNT) injection into the bladder wall has been shown to be an effective alternative to anticholinergic (antimuscarinic) medications and more invasive surgery in those with multiple sclerosis and spinal cord injury with neurogenic detrusor overactivity (NDO) and urinary incontinence who are not tolerating anticholinergic medications. In August 2011, Botox(®) (onabotulinumtoxinA) received Food and Drug Administration (FDA) approval for this use. Clinically, intradetrusor injection of BoNT has been found to decrease urinary incontinence and improve quality of life. Its impact on urodynamic parameters is an increase in the maximum cystometric (bladder) capacity and decrease in the maximum detrusor pressures. The most common side effects are urinary tract infections and urinary retention. There have been rare reports and a black box warning of distant spread of BoNT. BoNT has gained popularity because of its effectiveness and long duration of action, relative ease of administration, easy learning curve, reproducibility of results on repeated administration, and low incidence of complications.

OBJECTIVE

To discuss the structure and function, mechanisms of action, clinical and urodynamic studies, injection technique, potential beneficial and adverse effects, and potential areas of research of BoNT.

METHODS

Literature search focused on botulinum toxin in MEDLINE/PubMed. Search terms included botulinum toxin, neurogenic bladder, NDO, botox bladder, botox spinal cord injury, botox, FDA, botox side effects. All papers identified were English language, full-text papers. In addition, English abstracts of non-English papers were noted. The reference list of identified articles was also searched for further papers.

CONCLUSION

Botulinum toxin is an alternative treatment for individuals with NDO who fail to tolerate anticholinergic medications. Its popularity has increased because of the literature, which has supported its effectiveness, safety, easy use and learning curve, reproducibility of results on repeated use, and recent FDA approval of Botox(®) (onabotulinumtoxinA).

Botulinum toxin-A for the treatment of overactive bladder: UK contributions

Background:

Botulinum toxin-A (BoNT/A) is now established second-line management for refractory overactive bladder (OAB) and recognised in many incontinence guidelines and pathways. For those with neurogenic detrusor overactivity secondary to spinal cord injury or multiple sclerosis, the toxin is currently licensed in certain parts of the world, including the UK. It is an effective treatment in those in whom antimuscarinics and conservative measures have failed who have symptoms of OAB and or detrusor overactivity (DO).

Methods:

Treatment can be given in an outpatient setting and can be administered under local anaesthesia. Its efficacy lasts for between six and 12 months.

Results:

It has an acceptable safety profile with the biggest risk being urinary tract infection and difficulty emptying the bladder, necessitating clean intermittent self-catheterisation (CISC). Medium-term follow-up suggests repeated injections are also safe and efficacious.

Conclusions:

The mechanism of action of the toxin is more complicated than originally thought, and it seems likely that it affects motor and sensory nerves of the bladder. In the last 10 years much of the progress of this treatment from early experimental trials to mainstream clinical use, and a better understanding of how it works in the bladder, are as a result of research conducted in the UK. This review summarises the significant and substantial evidence for BoNT/A to treat refractory OAB from UK centres.

Neurogenic detrusor overactivity in patients with spinal cord injury: evaluation and management

Lower urinary tract dysfunction can have a significant impact on patients with spinal cord injury. Over the years, many treatment options have become available. This article reviews the assessment and management of neurogenic detrusor overactivity, with a particular focus on articles from the recent literature. Recent guidelines on the subject will be discussed. Management options include antimuscarinics and bladder emptying measures, botulinum toxin A, and neuromodulation in refractory cases and surgery for intractable cases. Recent and relevant publications in these areas will be summarized and discussed.

Efficacy and tolerability of botulinum toxin type A in patients with neurogenic detrusor overactivity and without concomitant anticholinergic therapy: comparison of two doses

BACKGROUND

Botulinum toxin type A (BoNTA) has been reported to be effective for treatment of patients with neurogenic detrusor overactivity (NDO) refractory to anticholinergic agents. However, in most of the studies, the efficacy was associated with concomitant use of anticholinergics.

OBJECTIVE

To evaluate the efficacy and tolerability of BoNTA and compare two different doses in patients with NDO without concomitant anticholinergics.

DESIGN, SETTING, AND PARTICIPANTS

Between 2004 and 2006, adults with NDO refractory to anticholinergics or discontinued anticholinergics due to adverse events or contraindications from four different French clinical centres were included in a prospective, randomised, double-blind, comparative trial. Inclusion criteria were urinary incontinence (UI) resulting from NDO that could not be managed with anticholinergics. Patients with bladder cancer, lithiasis, or urinary infection were excluded.

INTERVENTION

Patients were randomised to receive an intradetrusor injection of 500 U or 750 U of BoNTA.

MEASUREMENTS

The initial evaluation (ie, clinical and urodynamic variables and quality of life [QoL]) was repeated at days 30, 90, 180, and 360. Primary outcome was complete continence rate at day 30. Secondary outcomes were cumulative incontinence rate, reappearance of leakages, pad usage, urodynamics, and QoL.

RESULTS AND LIMITATIONS

Seventy-seven patients received 500 U (n=39) or 750 U (n=38) of BoNTA and were included in the full analysis set for efficacy analysis. Complete continence at day 30 was observed in 22 patients (56.4%) and 28 patients (73.7%) receiving 500 U or 750 U of BoNTA, respectively (p=0.056; one-sided χ(2) test to compare to α=0.025). The median delay in the reappearance of leakages was 168 d. Monotherapy of BoNTA significantly improved UI in patients with NDO. Although there was a trend towards a greater improvement with 750 U of BoNTA, no statistically significant differences in terms of clinical and urodynamic variables and QoL were found between the treatment groups. Tolerability was excellent and equivalent for both doses.

CONCLUSIONS

Monotherapy of BoNTA at Dysport (Ipsen, Brisbane, CA, USA) doses of 500 U or 750 U seems to be effective and well tolerated in patients with NDO.