Mechanisms of Disease: central nervous system involvement in overactive bladder syndrome

Post-stroke urinary incontinence is associated with behavior control deficits and overactive bladder

BACKGROUND

Although urinary incontinence in stroke survivors can substantially impact the patient's quality of life, the underlying neuropsychological mechanisms and its neural basis have not been adequately investigated. Therefore, we investigated this topic via neuropsychological assessment and neuroimaging in a cross-sectional study.

METHODS

We recruited 71 individuals with cerebrovascular disease. The relationship between urinary incontinence and neuropsychological indices was investigated using simple linear regression analysis or Mann-Whitney U test, along with other explanatory variables, e.g., severity of overactive bladder. Variables with a p-value of <0.1 in the simple regression analysis were entered in the final multiple linear regression model to control for potential confounding factors. To carry out an in-depth examination of the neuroanatomical substrate for urinary incontinence, voxel-based lesion-behavior mapping was performed using MRIcron software.

RESULTS

Behavioral control deficits and severity of overactive bladder were closely related to severity of urinary incontinence. The voxel-based lesion-behavior mapping suggests a potential role for ventromedial prefrontal cortex lesioning in the severity of urinary incontinence, although this association is not statistically significant.

CONCLUSIONS

Post-stroke urinary incontinence is closely related to two factors: neurogenic overactive bladder, a physiological disinhibition of micturition reflex, and cognitive dysfunction, characterized by behavior control deficits.

Lower urinary tract symptoms in young-middle aged males with a diagnosis of obstructive sleep apnea syndrome

BACKGROUND

The aim of the current study is to measure the prevalence and the potential role of International Prostate Symptom Score (IPSS) score as a predictor of obstructive sleep apnea syndrome (OSAS) in male experienced lower urinary tract symptoms (LUTS).

METHODS

A cross-sectional web-based Italian survey was administered via Google Forms between July 17 and October 31, 2022. The urinary functioning was measured through the IPSS questionnaire. Specifically, we considered symptoms occurring more than "about half the time" (score ≥ 3) as bothering symptoms. Multivariable logistic regression models (LRMs) adjusting for age, body mass index (BMI), International Index of Erectile Function-5, IPSS, and hypertension were fitted to predict OSAS in the cohort of men responding to the survey and experiencing LUTS.

RESULTS

Overall, 58 (24.4%) patients had a confirmed diagnosis of OSAS. The overall median IPSS was 5 (inter quartile range [IQR]: 3-8), respectively. According to IPSS items, 24 (10%), 44 (18.4%), 12 (5%), 12 (5%), 12 (5%), 11 (4.6%), 63 (26.4%) patients exhibit incomplete bladder emptying, urinary frequency, intermittency, urgency, weak stream, straining, nocturia with a score ≥ 3, respectively. After multivariable LRMs predicting the developing OSAS, age (odds ratio [OR]: 1.09, p < 0.001), BMI (OR:1.12, p < 0.001) and IPSS total score (OR:1.08, p = 0.02) were independent predicting factors.

CONCLUSION

This analysis revealed that the IPSS total score, age, and BMI are independent predictors of OSAS in males. In this context, the use of IPSS in daily practice could be helpful in assessing the LUTS presence and in supporting physicians to identify a hidden sleep apnea condition.

Transient receptor potential vanilloid type 4 (TRPV4) in urinary bladder structure and function

Bladder pain syndrome (BPS)/interstitial cystitis (IC) is a urologic, chronic pelvic pain syndrome characterized by pelvic pain, pressure, or discomfort with urinary symptoms. Symptom exacerbation (flare) is common with multiple, perceived triggers including stress. Multiple transient receptor potential (TRP) channels (TRPA1, TRPV1, TRPV4) expressed in the bladder have specific tissue distributions in the lower urinary tract (LUT) and are implicated in bladder disorders including overactive bladder (OAB) and BPS/IC. TRPV4 channels are strong candidates for mechanosensors in the urinary bladder and TRPV4 antagonists are promising therapeutic agents for OAB. In this perspective piece, we address the current knowledge of TRPV4 distribution and function in the LUT and its plasticity with injury or disease with an emphasis on BPS/IC. We review our studies that extend the knowledge of TRPV4 in urinary bladder function by focusing on (i) TRPV4 involvement in voiding dysfunction, pelvic pain, and non-voiding bladder contractions in NGF-OE mice; (ii) distention-induced luminal ATP release mechanisms and (iii) involvement of TRPV4 and vesicular release mechanisms. Finally, we review our lamina propria studies in postnatal rat studies that demonstrate: (i) the predominance of the TRPV4+ and PDGFRα+ lamina propria cellular network in early postnatal rats; (ii) the ability of exogenous mediators (i.e., ATP, TRPV4 agonist) to activate and increase the number of lamina propria cells exhibiting active Ca2+ events; and (iii) the ability of ATP and TRPV4 agonist to increase the rate of integrated Ca2+ activity corresponding to coupled lamina propria network events and the formation of propagating wavefronts.

Bladder Dysfunction in Older Adults: The Botulinum Toxin Option

Bladder dysfunction, which involves inadequacies of urine storage or emptying, increases with age. Conventional medications may have insufficient efficacy for patients with refractory lower urinary tract symptoms, and their concomitant adverse events (AEs) may be intolerable for the older adult population. For decades, the botulinum toxin type A (BoNT-A) injection has been an option for managing urine frequency, urge incontinence, and voiding dysfunction in the general population refractory to conventional management. This review focuses on studies of BoNT-A application in the management of bladder dysfunction in older adult patients aged ≥ 65 years. In this target population, intravesical BoNT-A injections provide similar efficacy in idiopathic overactive bladder to that in younger adults. Good clinical response has also been demonstrated in older adult patients presenting with storage dysfunction and with various concomitant underlying neurological diseases. However, caution must be taken for the AEs that occur after intravesical BoNT-A injection, including increased post-void residual urine, acute urine retention, and urinary tract infection. Most evidence shows that age is not a major determinant of AEs after adjusting for other factors. In contrast to its application in storage dysfunction, evidence for voiding dysfunction in older adults is scarce. In general, BoNT-A may be a reasonable option for older adult patients with refractory storage dysfunction because of its promising clinical response without significant systemic AEs. Overall, clinicians should be aware of the balance between the therapeutic efficacy of BoNT-A and local AEs in vulnerable members of this population.

Imatinib Mesylate Reduces Voiding Frequency in Female Mice With Acute Cyclophosphamide-Induced Cystitis

Lamina propria interstitial cells that express the tyrosine kinase receptor, platelet-derived growth factor receptor alpha (PDGFRα) may play a role in urinary sensory signaling. Imatinib mesylate, also referred to as imatinib, is a tyrosine kinase inhibitor that can inhibit PDGFRα and has been widely used in urological research. We evaluated the functional effects of imatinib administration (via oral gavage or intravesical infusion) with two different experimental designs (prevention and treatment), in a cyclophosphamide (CYP)-induced cystitis (acute, intermediate, and chronic), male and female rodent model using conscious cystometry and somatic sensitivity testing. Imatinib significantly (0.0001 ≤ p ≤ 0.05) decreased voiding frequency and increased bladder capacity in acute CYP-induced cystitis, by the prevention (females) and treatment (females and males) designs. Imatinib was not effective in preventing or treating intermediate or chronic CYP-induced cystitis in either sex. Interestingly, in the prevention experiments, imatinib administration increased (0.0001 ≤ p ≤ 0.01) voiding frequency and decreased bladder capacity in control mice. However, in the treatment experiments, imatinib administration decreased (0.01 ≤ p ≤ 0.05) voiding frequency and increased bladder capacity in control mice. Bladder function improvements observed with imatinib treatment in acute CYP-induced cystitis mice remained and additionally improved with a second dose of imatinib 24 hours after CYP treatment. Imatinib administration did not affect pelvic somatic sensitivity in female mice with acute CYP-induced cystitis. Our studies suggest that (1) imatinib improves bladder function in mice with acute CYP-induced cystitis with a prevention and treatment design and (2) interstitial cells may be a useful target to improve bladder function in cystitis.

Pathophysiological Mechanisms Underlying Idiopathic Normal Pressure Hydrocephalus: A Review of Recent Insights

The pathophysiologic mechanisms underpinning idiopathic normal pressure hydrocephalus (iNPH), a clinically diagnosed dementia-causing disorder, continue to be explored. An increasing body of evidence implicates multiple systems in the pathogenesis of this condition, though a unifying causative etiology remains elusive. Increased knowledge of the aberrations involved has shed light on the iNPH phenotype and has helped to guide prognostication for treatment with cerebrospinal fluid diversion. In this review, we highlight the central role of the cerebrovasculature in pathogenesis, from hydrocephalus formation to cerebral blood flow derangements, blood-brain barrier breakdown, and glymphatic pathway dysfunction. We offer potential avenues for increasing our understanding of how this disease occurs.

Video-urodynamic characteristics of lower urinary tract dysfunctions in patients with chronic brain disorders

AIMS

Lower urinary tract dysfunction (LUTD) is common in patients with chronic brain disorders. This study investigated the video-urodynamic study (VUDS) findings of LUTD in patients with chronic brain disorders, including cerebrovascular accident (CVA), Parkinson's disease (PD), and early dementia.

METHODS

A total of 169 patients with a history of chronic brain disorders, including 84 with CVA, 55 with PD, and 30 with early dementia were enrolled. All patients had a comprehensive chart review, including brain disorder subtype, the period from diagnosis to VUDS, the VUDS parameters, and final LUTD.

RESULTS

The mean age of patients was 69.2 ± 10.5 years, and the interval from brain insult to VUDS was 61.3 ± 49.7 months. Urodynamic detrusor overactivity (DO) was noted in 73.4% of patients, detrusor underactivity in 10.1%, and detrusor overactivity with detrusor underactivity in 16.6%. Bladder outlet obstruction (BOO) was noted in 60.9% of patients, including bladder neck dysfunction in 21.3%, urethral sphincter dysfunction in 42%, and prostatic obstruction in 10.1% of male patients. Urethral sphincter dysfunction was noted in 60% of patients with PD, 32.1% with CVA, and 36.7% with dementia (p = 0.004). A low mean maximum flow rate increased post-void residual volume, and poor voiding efficiency was common in these patients, without significant differences among the subgroups.

CONCLUSIONS

Real-world VUDSs revealed that patients with chronic brain disorders not only had a high prevalence of DO but also impaired bladder contractility and a high rate of BOO at the level above the bladder neck and urethral sphincter.

Intrabladder PAC1 Receptor Antagonist, PACAP(6-38), Reduces Urinary Bladder Frequency and Pelvic Sensitivity in Mice Exposed to Repeated Variate Stress (RVS)

Stress causes symptom exacerbation in functional disorders of the urinary bladder. However, the potential mediators and underlying mechanisms of stress effects on micturition reflex function are unknown. We have characterized PACAP (Adcyap1) and PAC1 receptor (Adcyap1r1) signaling in stress-induced urinary bladder dysfunction in mice. We determined PACAP and PAC1 transcripts and protein expressions in the urinary bladder and lumbosacral dorsal root ganglia (DRG) and spinal cord in repeated variate stress (RVS) or control mouse (handling only) groups. RVS in mice significantly (p ≤ 0.01) increased serum corticosterone and urinary bladder NGF content and decreased weight gain. PACAP and PAC1 mRNA and protein were differentially regulated in lower urinary tract tissues with changes observed in lumbosacral DRG and spinal cord but not in urinary bladder. RVS exposure in mice significantly (p ≤ 0.01) increased (2.5-fold) voiding frequency as determined using conscious cystometry. Intrabladder administration of the PAC1 receptor antagonist, PACAP(6-38) (300 nM), significantly (p ≤ 0.01) increased infused volume (1.5-2.7-fold) to elicit a micturition event and increased the intercontraction interval (i.e., decreased voiding frequency) in mice exposed to RVS and in control mice, but changes were smaller in magnitude in control mice. We also evaluated the effect of PAC1 blockade at the level of the urinary bladder on pelvic sensitivity in RVS or control mouse groups using von Frey filament testing. Intrabladder administration of PACAP(6-38) (300 nM) significantly (p ≤ 0.01) reduced pelvic sensitivity following RVS. PACAP/receptor signaling in the CNS and PNS contributes to increased voiding frequency and pelvic sensitivity following RVS and may represent a potential target for therapeutic intervention.

Evaluating the safety and potential activity of URO-902 (hMaxi-K) gene transfer by intravesical instillation or direct injection into the bladder wall in female participants with idiopathic (non-neurogenic) overactive bladder syndrome and detrusor overactivity from two double-blind, imbalanced, placebo-controlled randomized phase 1 trials

Aims

Two phase 1 trials were performed in healthy women with the overactive bladder (OAB) syndrome and urodynamically demonstrated detrusor overactivity (DO), with the aim to demonstrate the safety and potential efficacy of URO‐902, which comprises a gene therapy plasmid vector expressing the human big potassium channel α subunit.

Methods

ION‐02 (intravesical instillation) and ION‐03 (direct injection) were double‐blind, placebo‐controlled, multicenter studies without overlap in enrollment between studies. Active doses were administered and evaluated sequentially (lowest dose first) for safety. ION‐02 participants received either 5000 µg or 10 000 µg URO‐902, or placebo. ION‐03 participants received either 16 000 or 24 000 µg URO‐902, or placebo, injected directly into the bladder wall using cystoscopy. Primary outcome variables were safety parameters occurring subsequent to URO‐902 administration; secondary efficacy variables also were evaluated.

Results

Among the safety outcomes, there were no dose‐limiting toxicities or significant adverse events (AEs) preventing dose escalation during either trial, and no participants withdrew due to AEs. For efficacy, in ION‐02 (N = 21), involuntary detrusor contractions on urodynamics at 24 weeks in patients receiving URO‐902 (P < .0508 vs placebo) and mean urgency incontinence episodes in the 5000 µg group (P = .0812 vs placebo) each showed a downward trend. In ION‐03 (N = 13), significant reduction versus placebo in urgency episodes (16 000 µg, P = .036; 24 000 µg, P = .046) and number of voids (16 000 µg, −2.16, P = .044; 24 000 µg, −2.73, P = .047) were observed 1 week after injection.

Conclusion

Promising safety and efficacy results in these preliminary phase 1 studies suggest gene transfer may be a promising therapy for OAB/DO, warranting further investigation.

Cerebral White Matter Disease and Response to Anti-Cholinergic Medication for Overactive Bladder in an Age-Matched Cohort

OBJECTIVE

To determine if the presence of cerebral white matter disease (WMD) affects the response to anti-cholinergic medications.

MATERIALS AND METHODS

This was a retrospective cohort of age-matched patients treated for OAB with anti-cholinergic medications between January 2010 and December 2017. Inclusion criteria were a chief complaint of OAB, never evaluated by a urogynecologist for OAB, treated with a maximum dose for a minimum of 4 weeks, and underwent head computed tomography (CT) within 12 months of starting therapy. Patients with WMD were matched 1:1 by age and number of prior failed antimuscarinics to controls with normal head CTs. Exclusion criteria included incomplete documentation of therapeutic response, non-WMD CT abnormalities, and non-idiopathic OAB. The primary outcome was anti-cholinergic treatment failure. Pairwise analysis between groups was performed using Wilcoxon rank-sum and Fisher's exact test where appropriate. Univariate logistic regression was performed, and any variable that was associated with treatment failure and a p value ≤ 0.2 was included in the multivariable regression analysis.

RESULTS

Sixty-eight cases were matched with 68 controls. Patients with WMD were more likely to have undergone hysterectomy (57.4% vs. 41.2%, p = 0.04) and to use diuretics (31.1% vs. 19.1%, p = 0.04). Patients with WMD were more likely to fail treatment compared with controls (60.7% vs. 29.4%, p = 0.004). After adjusting for confounders, WMD was strongly associated with an increased probability of failure (aOR = 7.31, 95% CI: 1.49-12.20). Additional significant risk factors for treatment failure were the previous number of failed medications (aOR = 3.65 per medication, 95% CI: 1.48-9.01) and a rising HbA1c (aOR: 1.39 per 1.0% increase, 95% CI: 1.0-1.91).

CONCLUSION

WMD is independently associated with anti-muscarinic treatment failure in women with overactive bladder symptoms.

Risk of psychiatric disorders in overactive bladder syndrome: a nationwide cohort study in Taiwan

Population-based cohort study investigating the risk of depression and other psychiatric disorders for patients with overactive bladder (OAB) syndrome is unavailable. This study investigated the subsequent risk of psychiatric disorders among patients with OAB in an Asian population. Using data from the National Health Insurance Research Database of Taiwan, we established a cohort with 811 patients in an exposed group with OAB between January 1, 2000 and December 31, 2000, and a non-exposed group, without OAB, of 2433 patients without OAB matched by age and year of diagnosis. The occurrence of psychiatric disorders and Cox regression model measured adjusted HRs (aHR) were monitored until the end of 2013. The overall incidence of psychiatric disorders was 41.7% higher in the exposed group with OAB than in the non-exposed group without OAB (14.2% vs 10.1%, p<0.001), with an aHR of 1.34 (95% CI 1.12 to 1.80, p<0.001) for the OAB cohort. OAB was associated with the increased risk of dementia, anxiety, depressive, sleep, and psychotic disorders, with aHRs as 1.53 (p=0.040), 1.61 (p<0.001), 2.10 (p<0.001), 1.43 (p<0.001), and 2.49 (p=0.002), respectively. The risk of psychiatric disorders, including depression and anxiety, is significantly higher in patients with OAB than in those without OAB. Evaluation of psychiatric status in patients with OAB is strongly recommended.

Epidemiology of lower urinary tract symptoms in a cross-sectional, population-based study: The status in China

Lower urinary tract symptoms (LUTS) are reported to affect over half of all adults, and they are associated with significantly impaired quality of life (QOL). We performed a population-based study to evaluate the overall prevalence and impact of LUTS including overactive bladder (OAB) in adults aged ≥40 years in China.Adults aged ≥40 years were eligible to participate in this internet-based survey, provided that they had the ability to access the internet, to use a computer and to read the local language. The survey contained questions relating to International Continence Society (ICS) symptom definitions, the International Prostate Symptom Score (IPSS) and the Overactive Bladder Symptom Score (OABSS). The primary study objective was to determine the prevalence of LUTS using the ICS 2002 symptom definition.Among the 4136 respondents, 2080 (50.3%) were men and 1347 (32.6%) were aged ≥60 years. LUTS prevalence according to ICS criteria was 60.3% in men and 57.7% in women. All 3 ICS symptom groups (voiding, storage, and postmicturition) were present in 22.8% of women and 24.2% of men, making this the most common combination of ICS symptom groups. The most bothersome symptoms were terminal dribble and nocturia. According to IPSS scores, 32.9% of participants had at least moderate symptoms. The prevalence of OAB was 23.9%. The presence of LUTS-particularly all 3 ICS symptom groups-was associated with reduced sexual QOL in women, reduced satisfaction with erectile function in men, higher anxiety and depression scores, and reduced health-related QOL (physical health and mental health domains). The overall percentage of participants with LUTS visiting healthcare professionals for urinary symptoms was 38%.In conclusion, LUTS affect the majority of adults aged ≥40 years in China, and prevalence increases with increasing age. LUTS are associated with impaired QOL and mental health, but fewer than half of individuals in China with LUTS seek healthcare for their symptoms. There is therefore a need to improve awareness and treatment of the condition.ClinicalTrials.gov identifier: NCT02618421.

Overactive bladder syndrome and bladder wall thickness in patients with obstructive sleep apnea syndrome

Objective

The main objective of the present study was to evaluate the presence of overactive bladder (OAB) syndrome, nocturia, urgency, and urge incontinence in patients with obstructive sleep apnea syndrome (OSAS), and measure bladder wall thickness (BWT) in these patients.

Materials and Methods

The patient group was composed of 38 patients with OSAS. The control group was composed of 15 healthy individuals. All patients were evaluated using the Epworth Sleepiness Scale (ESS) and Overactive Bladder Symptom Score (OABSS). The bladder wall thickness was measured by transabdominal ultrasound (US). The presence of nocturia, urinary urgency, and urge incontinence were also evaluated.

Results

The mean OABSS was significantly higher in the patient group compared with the control group (p=0.048). The minimum oxygen saturation (Min.SO₂) of patients with urgency was found to be significantly lower (p=0.014). The time spent below 90% of oxygen saturation (SO₂) was significantly longer in patients with urinary urgency (p=0.009). There was no difference in BWT measurements between the patient group and the control group. There was a significant relationship between BWT values and OABSS in patients with OSAS (p=0.002).

Conclusion

The results of the present study suggest that OSAS is associated with OAB syndrome. As a key symptom of OAB, urgency correlates with hypoxia in cases with OSAS. Although the present study did not observe any difference in BWT measurements between the patients and the control group, there was a correlation between BWT measurements and OABSS in patients with OSAS.

Rhythmic Calcium Events in the Lamina Propria Network of the Urinary Bladder of Rat Pups

The lamina propria contains a dense network of cells, including interstitial cells (ICs), that may play a role in bladder function by modulating communication between urothelium, nerve fibers and smooth muscle or acting as pacemakers. Transient receptor potential vanilloid 4 (TRPV4) channels allow cation influx and may be involved in sensing stretch or chemical irritation in urinary bladder. Urothelium was removed from rats (P0-Adult), cut into strips, and loaded with a Ca²⁺ fluorescent dye (Fluo-2 AM leak resistant or Cal 520) for 90 min (35-37°C) to measure Ca²⁺ events. Ca²⁺ events were recorded for a period of 60 seconds (s) in control and after drug treatment. A heterogeneous network of cells was identified at the interface of the urothelium and lamina propria of postnatal rat pups, aged ≤ postnatal (P) day 21, with diverse morphology (round, fusiform, stellate with numerous projections) and expressing platelet-derived growth factor receptor alpha (PDGFRα)- and TRPV4-immunoreactivity (IR). Ca²⁺ transients occurred at a slow frequency with an average interval of 30 ± 8.6 s. Waveform analyses of Ca²⁺ transients in cells in the lamina propria network revealed long duration Ca²⁺ events with slow upstrokes. We observed slow propagating waves of activity in the lamina propria network that displayed varying degrees of coupling. Application of the TRPV4 agonist, GSK1016790 (100 nM), increased the duration of Ca²⁺ events, the number of cells with Ca²⁺ events and the integrated Ca²⁺ activity corresponding to propagation of activity among cells in the lamina propria network. However, GSK2193874 (1 μM), a potent antagonist of TRPV4 channels, was without effect. ATP (1 μM) perfusion increased the number of cells in the lamina propria exhibiting Ca²⁺ events and produced tightly coupled network activity. These findings indicate that ATP and TRPV4 can activate cells in the laminar propria network, leading to the appearance of organized propagating wavefronts.

PACAP/Receptor System in Urinary Bladder Dysfunction and Pelvic Pain Following Urinary Bladder Inflammation or Stress

Complex organization of CNS and PNS pathways is necessary for the coordinated and reciprocal functions of the urinary bladder, urethra and urethral sphincters. Injury, inflammation, psychogenic stress or diseases that affect these nerve pathways and target organs can produce lower urinary tract (LUT) dysfunction. Numerous neuropeptide/receptor systems are expressed in the neural pathways of the LUT and non-neural components of the LUT (e.g., urothelium) also express peptides. One such neuropeptide receptor system, pituitary adenylate cyclase-activating polypeptide (PACAP; Adcyap1) and its cognate receptor, PAC1 (Adcyap1r1), have tissue-specific distributions in the LUT. Mice with a genetic deletion of PACAP exhibit bladder dysfunction and altered somatic sensation. PACAP and associated receptors are expressed in the LUT and exhibit neuroplastic changes with neural injury, inflammation, and diseases of the LUT as well as psychogenic stress. Blockade of the PACAP/PAC1 receptor system reduces voiding frequency in preclinical animal models and transgenic mouse models that mirror some clinical symptoms of bladder dysfunction. A change in the balance of the expression and resulting function of the PACAP/receptor system in CNS and PNS bladder reflex pathways may underlie LUT dysfunction including symptoms of urinary urgency, increased voiding frequency, and visceral pain. The PACAP/receptor system in micturition pathways may represent a potential target for therapeutic intervention to reduce LUT dysfunction.

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

Overactive bladder (OAB) symptoms increase with age and involve several comorbidities. OnabotulinumtoxinA (BoNT-A) intravesical injection is a treatment choice for patients who are intolerant of or refractory to antimuscarinics. However, the increased risk of urinary tract infection and elevated post-void residual (PVR) volume post-treatment require resolution. Male sex, baseline PVR > 100 mL, and comorbidities are independent risk factors of adverse events (AEs) such as acute urinary retention (AUR). Intravesical BoNT-A injection is safe and effective for OAB patients with frailty, medical comorbidities such as Parkinson's disease (PD), chronic cerebrovascular accidents (CVA), dementia, or diabetes, or a history of prior lower urinary tract surgery (prostate or transvaginal sling surgery). Post-treatment, 60% of frail elderly patients had a PVR volume > 150 mL and 11% had AUR. Although intravesical BoNT-A injection is safe for PD patients, CVA patients had higher strain voiding rates. Diabetic patients were at increased risk of large PVR urine volume and general weakness post-treatment. Treatment results were similar between patients with and without a history of prostate or transvaginal sling surgery. Possible AEs and bladder management strategies should be conveyed to patients before treatment. Careful patient selection is important, and therapeutic safety and efficacy should be carefully balanced.

Practical points in the medical treatment of overactive bladder and nocturia in the elderly

The prevalence of overactive bladder (OAB) increases with age. Degeneration of the central nervous system in the elderly has been proposed as one of the pathogenic factors of OAB. Antimuscarinic therapy is effective in the treatment of OAB; however, intolerable systemic adverse events and cognitive dysfunction during treatment with nonselective antimuscarinic agents is of growing concern in elderly patients. The newly developed beta-3 adrenoceptor agonist mirabegron does not adversely affect flow rate and detrusor pressure, and its therapeutic efficacy and tolerability are similar in patients aged > 65 years and > 75 years, suggesting it might be the therapeutic choice in older patients with OAB. Nocturia can cause sleep deprivation at night and increase daytime sleepiness and loss of energy in the elderly. Desmopressin add-on therapy is effective in improving nocturia and storage symptoms. However, elderly patients with a baseline serum sodium level below the normal range are at high risk of developing significant hyponatremia.

Practical Aspects of Botulinum Toxin-A Treatment in Patients With Overactive Bladder Syndrome

Intravesical onabotulinumtoxinA (BoNT-A) injection is an effective treatment for overactive bladder syndrome (OAB) that is refractory to antimuscarinics. An injectable dose of 100 U has been suggested to achieve the optimal balance of benefit and safety in patients with OAB. BoNT-A (total volume of 10 mL) was administered as evenly distributed intradetrusor injections (5 U) across 20 sites approximately 1 cm apart (0.5 mL per site) using a flexible or rigid cystoscope. Treatment with BoNT-A was generally well tolerated by most patients, and most treatment-related adverse events were localized to the urinary tract. The prevalence of OAB increases with age, and elderly patients are more vulnerable to complications. The short-term efficacy of intravesical BoNT-A injection for refractory OAB with no treatment-related complications in the elderly population has been documented. Frail elderly patients can experience the same treatment results, such as significantly improved urgent urinary incontinence and quality of life, as young and nonfrail elderly patients with 100-U BoNT-A injections. However, increased risk of larger postvoid residual (PVR) urine and lower long-term success rates were noted in frail elderly patients; around 11% had acute urinary retention, while 60% had PVR urine volume >150 mL after treatment. In addition, intravesical injection of BoNT-A effectively decreased urgency symptoms in elderly patients with OAB and central nervous system lesions. The adverse effects were acceptable, while the long-term effects were comparable to those in patients with OAB without central nervous system lesions. Nonetheless, the possibility of longstanding urinary retention and chronic catheterization in this vulnerable population requires careful evaluation before treatment with intravesical BoNT-A. In conclusion, the current findings indicate that intravesical BoNT-A is an effective and safe treatment for OAB in elderly patients.

OnabotulinumtoxinA Treatment for Overactive Bladder in the Elderly: Practical Points and Future Prospects

Overactive bladder (OAB) increases with age. OAB in the elderly may be associated with increased risks of falls, fractures and mortality. Degeneration of the central nervous system in the elderly is proposed as one of the pathogenic factors for OAB. Recently, onabotulinumtoxinA (BoNT-A) 100 U has been demonstrated to be well tolerated, and it significantly improves all OAB symptoms and health-related quality of life in patients who are inadequately managed with anticholinergics. However, an increased risk of a large post-void residual volume and a lower long-term success rate were noted in frail elderly patients. Careful patient selection for BoNT-A injection treatment is important in elderly OAB patients. Patients who are frail, are elderly, have comorbidity or have a post-void residual volume >100 mL should be monitored carefully after BoNT-A injection treatment to prevent urinary retention and subsequent urinary tract infection. Use of liposomes to carry BoNT-A across the urothelial barrier decreases urgency-frequency episodes without compromising detrusor contractility and might avoid urinary tract infection. This treatment might prevent undesired detrusor underactivity after BoNT-A injection treatment, especially in elderly patients who have low detrusor contractility. For treatment of OAB in the elderly, clinicians should be aware of the balance between therapeutic efficacy and safety.

Bladder outlet obstruction causes up-regulation of nicotinic acetylcholine receptors in bladder-projecting pelvic ganglion neurons

Pelvic ganglion (PG) neurons relay sympathetic and parasympathetic signals to the lower urinary tract, comprising the urinary bladder and bladder outlet, and are thus essential for both storage and voiding reflexes. Autonomic transmission is mediated by activation of the nicotinic acetylcholine receptor (nAChR) in PG neurons. Previously, bladder outlet obstruction (BOO), secondary to benign prostatic hyperplasia, was found to increase soma sizes of bladder-projecting PG neurons. To date, however, it remains unknown whether these morphological changes are accompanied by functional plasticity in PG neurons. In the present study, we investigated whether BOO alters acetylcholine receptor (nAChR) transcript expression and current density in bladder PG neurons. Partial ligation of the rat urethra for six weeks induced detrusor overactivity (DO), as observed during cystometrical measurement. In rats exhibiting DO, membrane capacitance of parasympathetic bladder PG neurons was selectively increased. Real-time PCR analysis revealed that BOO enhanced the expression of the transcripts encoding the nAChR α3 and β4 subunits in PG neurons. Notably, BOO significantly increased ACh-evoked current density in parasympathetic bladder PG neurons, whereas no changes were observed in sympathetic bladder and parasympathetic penile PG neurons. In addition, other ligand-gated ionic currents were immune to BOO in bladder PG neurons. Taken together, these data suggest that BOO causes upregulation of nAChR in parasympathetic bladder PG neurons, which in turn may potentiate ganglionic transmission and contribute to the development of DO.

A guideline for the management of bladder dysfunction in Parkinson's disease and other gait disorders

Parkinson's disease (PD) is a common neurodegenerative disorder, and lower urinary tract (LUT) dysfunction is one of the most common autonomic disorders with an estimated incidence rate of 27-80%. Studies have shown that bladder dysfunction significantly influences quality-of-life (QOL) measures, early institutionalisation, and health economics. We review the pathophysiology of bladder dysfunction in PD, lower urinary tract symptoms (LUTS), objective assessment, and treatment options. In patients with PD, disruption of the dopamine D1-GABAergic direct pathway may lead to LUTS. Overactive bladder (OAB) is the most common LUT symptom in PD patients, and an objective assessment using urodynamics commonly shows detrusor overactivity (DO) in these patients. The post-void residual (PVR) volume is minimal in PD, which differs significantly from multiple system atrophy (MSA) patients who have a more progressive disease that leads to urinary retention. However, subclinical detrusor weakness during voiding may also occur in PD. Regarding bladder management, there are no large, double-blind, prospective studies in this area. It is well recognised that dopaminergic drugs can improve or worsen LUTS in PD patients. Therefore, an add-on therapy with anticholinergics is required. Beta-3 adrenergic agonists are a potential treatment option because there are little to no central cognitive events. Newer interventions, such as deep brain stimulation (DBS), are expected to improve bladder dysfunction in PD. Botulinum toxin injections can be used to treat intractable urinary incontinence in PD. Transurethral resection of the prostate gland (TURP) for comorbid BPH in PD is now recognised to be not contraindicated if MSA is excluded. Collaboration of urologists with neurologists is highly recommended to maximise a patients' bladder-associated QOL. Neurourol. Urodynam. 35:551-563, 2016. © 2015 Wiley Periodicals, Inc.

Efficacy and safety of intravesical onabotulinumtoxinA injection on elderly patients with chronic central nervous system lesions and overactive bladder

PURPOSE

Intravesical injection of onabotulinumtoxinA is an effective treatment for overactive bladder (OAB). Nonetheless, the treatment outcome is unclear in OAB patients with central nervous system (CNS) lesions. This study evaluated the efficacy and safety of intravesical onabotulinumtoxinA treatment in elderly patients with chronic cerebrovascular accidents (CVAs), Parkinson's disease (PD) and dementia.

MATERIALS AND METHODS

Patients with CVA, PD, dementia, and OAB refractory to antimuscarinic therapy were consecutively enrolled in the study group. Age-matched OAB patients without CNS lesions were selected to serve as a control group. OnabotulinumtoxinA (100 U) was injected into the bladder suburothelium at 20 sites. The clinical effects, adverse events, and urodynamic parameters were assessed at baseline and 3 months post-treatment. The Kaplan-Meier method was used to compare long-term success rates between groups.

RESULTS

A total of 40 patients with OAB due to CVA (23), PD (9), dementia (8) and 160 control patients were included in this retrospetive analysis. Improvement of urgency severity scale, increased bladder capacity and increased post-void residual volume were comparable between the groups at 3 months. Patients with CNS lesions did not experience increased risks of acute urinary retention and urinary tract infection; nonetheless, patients with CVA experienced a higher rate of straining to void. Long-term success rates did not differ between the patients with and without CNS lesions.

CONCLUSION

Intravesical injection of 100 U of onabotulinumtoxinA effectively decreased urgency symptoms in elderly OAB patients with CNS lesions. The adverse events were acceptable, and long-term effects were comparable to OAB patients in general. Nonetheless, the possibility of longstanding urinary retention and chronic catheterization need careful evaluation for this very vulnerable population before choosing intravesical onabotulinumtoxinA treatment.

Bladder sensory physiology: neuroactive compounds and receptors, sensory transducers, and target-derived growth factors as targets to improve function

Urinary bladder dysfunction presents a major problem in the clinical management of patients suffering from pathological conditions and neurological injuries or disorders. Currently, the etiology underlying altered visceral sensations from the urinary bladder that accompany the chronic pain syndrome, bladder pain syndrome (BPS)/interstitial cystitis (IC), is not known. Bladder irritation and inflammation are histopathological features that may underlie BPS/IC that can change the properties of lower urinary tract sensory pathways (e.g., peripheral and central sensitization, neurochemical plasticity) and contribute to exaggerated responses of peripheral bladder sensory pathways. Among the potential mediators of peripheral nociceptor sensitization and urinary bladder dysfunction are neuroactive compounds (e.g., purinergic and neuropeptide and receptor pathways), sensory transducers (e.g., transient receptor potential channels) and target-derived growth factors (e.g., nerve growth factor). We review studies related to the organization of the afferent limb of the micturition reflex and discuss neuroplasticity in an animal model of urinary bladder inflammation to increase the understanding of functional bladder disorders and to identify potential novel targets for development of therapeutic interventions. Given the heterogeneity of BPS/IC and the lack of consistent treatment benefits, it is unlikely that a single treatment directed at a single target in micturition reflex pathways will have a mass benefit. Thus, the identification of multiple targets is a prudent approach, and use of cocktail treatments directed at multiple targets should be considered.

Bladder health across the life course

Influences on bladder health begin during infancy and continue throughout the lifespan. Bladder anatomy and physiology change as individuals age, and the risk and propensity for bladder conditions, including lower urinary tract symptoms, throughout life are related to factors specific to age, sex, and life events. Bladder habits and dysfunctions at one stage of life may affect bladder health in subsequent stages. However, bladder problems are neither a normal part of aging nor inevitable at any stage of life. Many of the factors that negatively impact bladder health at all ages may be modifiable, and healthy bladder habits may prevent or reverse bladder dysfunctions that can occur naturally or in response to life events. There are opportunities to further define and promote healthy bladder habits through focused research and heightened public awareness of the importance of bladder health, which may lead to improvements in overall health and quality of life. It is our hope that this paper will inform and encourage public health initiatives and research programs aimed at this goal.

High classification of chronic heart failure increases risk of overactive bladder syndrome and lower urinary tract symptoms

OBJECTIVE

To assess the urologic symptoms among patients with chronic heart failure (CHF) and to explore whether a higher classification of CHF increases the risk associated with overactive bladder syndrome (OAB) and lower urinary tract symptoms.

METHODS

A total of 214 ambulatory patients with CHF (129 men and 85 women) and 378 age-matched subjects (222 men and 156 women) were enrolled in the present study. The urologic symptoms were evaluated using the Overactive Bladder Symptom Score (OABSS) and International Prostate Symptom Score (IPSS) from January to June 2010.

RESULTS

Compared with the controls, the patients with CHF had a significantly greater mean OABSS (4.6±3.6 vs 3.4±3.1, P<.001), total IPSS (8.3±6.9 vs 6.9±7.6, P=.021), and storage IPSS (4.8±3.5 vs 3.7±3.3, P<.001). Of the patients with CHF, 34.1% had moderate/severe OAB symptoms (OABSS≥6), and 43.5% had moderate/severe lower urinary tract symptoms (IPSS≥8). Compared with patients who had New York Heart Association (NYHA) class I CHF, the patients with NYHA class III CHF had a significantly greater OABSS and total, storage, and voiding IPSSs. Patients with NYHA class II CHF did not. A greater body mass index and stroke were significantly associated with the OABSS and storage IPSS, and pulmonary disease was significantly associated with the voiding IPSS.

CONCLUSION

The patients with CHF had more storage urinary symptoms suggestive of OAB than did the age-matched controls. Among the patients with CHF, greater NYHA class heart function was significantly associated with OAB and lower urinary tract symptoms.

Pathophysiology of bladder dysfunction in Parkinson's disease

Bladder dysfunction (urinary urgency/frequency) is a common non-motor disorder in Parkinson's disease (PD). In contrast to motor disorders, bladder dysfunction is sometimes non-responsive to levodopa treatment. The brain pathology causing the bladder dysfunction (appearance of overactivity) involves an altered dopamine basal ganglia-frontal circuit, which normally suppresses the micturition reflex. The pathophysiology of the bladder dysfunction in PD differs from that in multiple system atrophy; therefore, it might aid in differential diagnosis. Anticholinergic agents are used to treat bladder dysfunction in PD, although these drugs should be used with caution particularly in elderly patients who have cognitive decline. These treatments might be beneficial in maximizing the patients' quality of life.

Bladder, bowel, and sexual dysfunction in Parkinson's disease

Bladder dysfunction (urinary urgency/frequency), bowel dysfunction (constipation), and sexual dysfunction (erectile dysfunction) (also called “pelvic organ” dysfunctions) are common nonmotor disorders in Parkinson's disease (PD). In contrast to motor disorders, pelvic organ autonomic dysfunctions are often nonresponsive to levodopa treatment. The brain pathology causing the bladder dysfunction (appearance of overactivity) involves an altered dopamine-basal ganglia circuit, which normally suppresses the micturition reflex. By contrast, peripheral myenteric pathology causing slowed colonic transit (loss of rectal contractions) and central pathology causing weak strain and paradoxical anal sphincter contraction on defecation (PSD, also called as anismus) are responsible for the bowel dysfunction. In addition, hypothalamic dysfunction is mostly responsible for the sexual dysfunction (decrease in libido and erection) in PD, via altered dopamine-oxytocin pathways, which normally promote libido and erection. The pathophysiology of the pelvic organ dysfunction in PD differs from that in multiple system atrophy; therefore, it might aid in differential diagnosis. Anticholinergic agents are used to treat bladder dysfunction in PD, although these drugs should be used with caution particularly in elderly patients who have cognitive decline. Dietary fibers, laxatives, and “prokinetic” drugs such as serotonergic agonists are used to treat bowel dysfunction in PD. Phosphodiesterase inhibitors are used to treat sexual dysfunction in PD. These treatments might be beneficial in maximizing the patients' quality of life.

Detrusor overactivity persisting at night and preceding nocturia in patients with overactive bladder syndrome: a nocturnal cystometrogram and polysomnogram study

PURPOSE

Nocturia, a common symptom of overactive bladder syndrome, is associated with substantial adverse consequences and yet its pathophysiology has hardly been studied and the capacity to treat it remains limited. We established methods to study the physiology of overactive bladder associated nocturia and better understand this phenomenon.

MATERIALS AND METHODS

We recorded simultaneous, time aligned, nocturnal cystometrogram and polysomnogram data during a single night at a sleep laboratory in 9 patients with overactive bladder and detrusor overactivity on daytime cystometrogram, in 10 patients with insomnia and in 5 healthy controls.

RESULTS

We safely recorded simultaneous polysomnography/nocturnal cystometrography data accurately during the sleep period. Nocturnal detrusor overactivity occurred significantly less often in patients with insomnia and controls than in patients with detrusor overactivity plus overactive bladder (p = 0.02) and only in the 10 minutes before nocturia events in the latter (0%, 0% and 67%, respectively, p = 0.002). Patients with detrusor overactivity plus overactive bladder were awake for a shorter period before nocturia events (p <0.001) and had a greater percent of nocturia associated awakenings. Patients with insomnia had more awakenings unrelated to nocturia. Nocturnal polyuria, another cause of nocturia, was not significantly associated with nocturnal detrusor overactivity.

CONCLUSIONS

Sleep and bladder pressure physiology may be safely monitored during the sleep period accurately. Nocturnal detrusor overactivity occurs in association with nocturia in most patients with detrusor overactivity plus overactive bladder, does not generally occur during sleep and is not due to sleep disturbance or nocturnal polyuria. This study may provide a foundation for research on overactive bladder related nocturia pathophysiology and treatment.

The safety and efficacy of tolterodine extended release in the treatment of overactive bladder in the elderly

After lifestyle and behavioral measures to control overactive bladder, the mainstay of pharmacological treatment is the use of antimuscarinic therapy. Overactive bladder predominantly affects older people, who experience the most severe disease, and are also at a greater risk of side effects from antimuscarinic therapy. Thus it is imperative that data are available on the efficacy and tolerability of this group of drugs when used in older people. This article reviews the pathophysiology of the condition, its effect on the elderly and the evidence for the use of extended release tolterodine in the elderly using data from placebo and active drug controlled studies.

Obstructive sleep apnea syndrome is associated with overactive bladder and urgency incontinence in men

STUDY OBJECTIVE

To investigate the incidence of overactive bladder (OAB) and urgency incontinence (UI) in men with obstructive sleep apnea syndrome (OSAS).

DESIGN

Prospective questionnaire study

SETTING

Saarland University Hospital

PATIENTS

All male patients who underwent full-night in-laboratory polysomnography between November 2006 and April 2007.

INTERVENTIONS

Overactive bladder symptom score (OABSS) and International Consultation on Incontinence Questionnaire, Short-Form (ICIQ-SF).

MEASUREMENTS AND RESULTS

OSAS severity was assessed according to the apnea-hypopnea-index (AHI). Return rate of questionnaires was 100% (n=100). Patients with upper airway resistance syndrome (UARS) served as controls. Evaluation of OABSS revealed that patients with moderate and severe OSAS presented with a significantly higher incidence of symptoms of OAB than patients with mild OSAS and UARS (P<0.05). Further, the ICIQ-SF revealed a higher occurrence of UI in patients with severe OSAS than in those with mild OSAS and UARS (P<.05).

CONCLUSIONS

Increasing severity of OSAS appears to be associated with an increasing occurrence of overactive bladder and urgency incontinence in men. This relationship may have clinical implications for the treatment of affected patients.

Emerging drugs for treatment of overactive bladder and detrusor overactivity

BACKGROUND

Overactive bladder (OAB) signifies the presence of urinary urgency and can have major effects on quality of life and social functioning. Standard antimuscarinic drugs have good initial response rates but substantial adverse effects and long-term compliance problems.

OBJECTIVES

To review the complexities of the mechanisms underlying OAB and the current drugs available for treating its symptoms.

METHODS

The literature was reviewed to define current therapies and drugs in clinical trials. Articles were identified by means of a computerised PubMed and Cochrane Library search (using the following keywords: overactive bladder, detrusor overactivity, urgency and bladder), supported by a search of the PharmaProjects database.

CONCLUSIONS

New drug classes, such as beta-3 adrenergic agonists, may work by reducing contractility or excitability of bladder muscle. Moderation of afferent activity may allow improved OAB symptoms, with lower risk of affecting voiding function. Agents acting on the CNS could influence OAB favourably, but target selection and adverse effects are an issue. The recognition of the functional contribution of the urothelium and the diversity of nerve transmitters has sparked interest in both peripheral and central modulation of OAB pathophysiology.

Bladder control, urgency, and urge incontinence: evidence from functional brain imaging

AIM

To review brain imaging studies of bladder control in subjects with normal control and urge incontinence; to define a simple model of supraspinal bladder control; and to propose a neural correlate of urgency and possible origins of urge incontinence.

METHODS

Review of published reports of brain imaging relevant to urine storage, and secondary analyses of our own recent observations.

RESULTS

In a simple model of normal urine storage, bladder and urethral afferents received in the periaqueductal gray (PAG) are mapped in the insula, forming the basis of sensation; the anterior cingulate gyrus (ACG) provides monitoring and control; the prefrontal cortex makes voiding decisions. The net result, as the bladder fills, is inhibition of the pontine micturition center (PMC) and of voiding, together with gradual increase in insular response, corresponding to increasing desire to void. In urge-incontinent subjects, brain responses differ. At large bladder volumes and strong sensation, but without detrusor overactivity (DO), most cortical responses become exaggerated, especially in ACG. This may be both a learned reaction to previous incontinence episodes and the neural correlate of urgency. The neural signature of DO itself seems to be prefrontal deactivation. Possible causes of urge incontinence include dysfunction of prefrontal cortex or limbic system, suggested by weak responses and/or deactivation, as well as abnormal afferent signals or re-emergence of infantile reflexes.

CONCLUSIONS

Bladder control depends on an extensive network of brain regions. Dysfunction in various parts may contribute to urge incontinence, suggesting that there are different phenotypes requiring different treatments.