Management of overactive bladder

Real-time prediction of bladder urine leakage using fuzzy inference system and dual Kalman filtering in cats

The use of electrical stimulation devices to manage bladder incontinence relies on the application of continuous inhibitory stimulation. However, continuous stimulation can result in tissue fatigue and increased delivered charge. Here, we employ a real-time algorithm to provide a short-time prediction of urine leakage using the high-resolution power spectrum of the bladder pressure during the presence of non-voiding contractions (NVC) in normal and overactive bladder (OAB) cats. The proposed method is threshold-free and does not require pre-training. The analysis revealed that there is a significant difference between voiding contraction (VC) and NVC pressures as well as band powers (0.5-5 Hz) during both normal and OAB conditions. Also, most of the first leakage points occurred after the maximum VC pressure, while all of them were observed subsequent to the maximum VC spectral power. Kalman-Fuzzy method predicted urine leakage on average 2.2 s and 1.6 s before its occurrence and an average of 2.0 s and 1.1 s after the contraction started with success rates of 94.2% and 100% in normal and OAB cats, respectively. This work presents a promising approach for developing a neuroprosthesis device, with on-demand stimulation to control bladder incontinence.

Mediterranean Diet and Overactive Bladder

Purpose: The relationship between nutrition and overactive bladder (OAB) has yet to be elucidated. Therefore, this study investigated the relationship between the Mediterranean diet and OAB.Methods: The 14-item Mediterranean Diet Adherence Screener (MeDAS) and Overactive Bladder-Validated 8-question Screener (OAB-V8), validated in Turkish, were administered to 500 patients over the age of 18 who presented to outpatient clinics other than urology outpatient clinics. Of those patients, 174 with chronic diseases and urinary tract infections (based on urinalysis and a detailed medical history) were excluded. Therefore, 326 patients’ data were analyzed.Results: There was a negative correlation between the MeDAS and OAB-V8 scores. High OAB-V8 scores were associated with obesity (body mass index ≥30 kg/m²), being single, and a low education level.Conclusions: Dietary patterns represent a broader perspective on food and nutrient consumption and may therefore be more predictive of disease risk. The Mediterranean type should be recommended in the first-line treatment of patients with OAB symptoms. It is easily possible to determine the compliance of patients with this diet by using the 14-item MeDAS.

Evaluation and Treatment in Urology for Nocturia Caused by Nonurological Mechanisms: Guidance from the PLANET Study

Patients with nocturia are commonly referred to urology clinics, including many for whom a nonurological medical condition is responsible for their symptoms. The PLanning Appropriate Nocturia Evaluation and Treatment (PLANET) study was established to develop practical approaches to equip healthcare practitioners to deal with the diverse causes of nocturia, based on systematic reviews and expert consensus. Initial assessment and therapy need to consider the possibility of one or more medical conditions falling into the "SCREeN" areas of Sleep medicine (insomnia, periodic limb movements of sleep, parasomnias, and obstructive sleep apnoea), Cardiovascular (hypertension and congestive heart failure), Renal (chronic kidney disease), Endocrine (diabetes mellitus, thyroid disease, pregnancy/menopause, and diabetes insipidus), and Neurology. Medical and medication causes of xerostomia should also be considered. Some key indicators for these conditions can be identified in urology clinics, working in partnership with the primary care provider. Therapy of the medical condition in some circumstances lessens the severity of nocturia. However, in many cases there is a conflict between the two, in which case the medical condition generally takes priority on safety grounds. It is important to provide patients with a realistic expectation of therapy and awareness of limitations of current therapeutic options for nocturia. PATIENT SUMMARY: Nocturia is the symptom of waking at night to pass urine. Commonly, this problem is referred to urology clinics. However, in some cases, the patient does not have a urological condition but actually a condition from a different speciality of medicine. This article describes how best the urologist and the primary care doctor can work together to assess the situation and make sensible and safe treatment suggestions. Unfortunately, there is sometimes no safe or effective treatment choice for nocturia, and treatment needs to focus instead on supportive management of symptoms.

Assessment and Treatment of Nocturia in Neurological Disease in a Primary Care Setting: Systematic Review and Nominal Group Technique Consensus

CONTEXT

Neurological disease can affect the rate of urine production and bladder storage function, increasing nocturia severity, with additional risks if mobility or cognition is impaired.

OBJECTIVE

To conduct a systematic review (SR) of nocturia in neurological diseases and achieve expert consensus for management in clinics without neurologist input.

EVIDENCE ACQUISITION

Four databases were searched from January 2000 to April 2020. A total of 6262 titles and abstracts were screened and 43 studies were included for full-text screening. Eleven of these met the inclusion criteria and two studies were identified through other sources. The nominal group technique (NGT) was used to develop consensus in panel comprising experts and public representation.

EVIDENCE SYNTHESIS

Thirteen studies (seven in Parkinson's disease, five in multiple sclerosis) were included, all undertaken in secondary care. Neurological disease severity was incompletely described, and nocturia severity was generally measured subjectively. NGT consensus supported basic neurological assessment, and the use of bladder diaries where neurological impairment permits. Treatments include pelvic-floor muscle training, review of medications, risk mitigation, improving bowel function, therapy for overactive bladder syndrome (if urgency is reported in association with nocturia episodes), treatment of postvoid residual and desmopressin according to licence. Measures to improve mobility and mitigate risk when using the toilet overnight should be considered. Multifactorial issues such as obstructive sleep apnoea and hypoventilation must be considered.

CONCLUSIONS

Nocturia in neurological disease is complex and lacks a robust evidence base, with very little research done in the primary care context. Guidance should be pragmatic, with reduction of risk a key requirement, until a multidisciplinary evidence base can be developed.

PATIENT SUMMARY

People with a neurological disease can suffer severe sleep disturbance because of the need to pass urine several times overnight (called nocturia). We looked at published research and found very little information to help general practitioners in managing this condition. We assembled a group of experts to develop practical approaches for assessing and treating nocturia in neurological disease.

Use of the International Consultation on Incontinence Questionnaires Bladder Diary in Men Seeking therapy for Lower Urinary Tract Symptoms

BACKGROUND

Completion rates and correspondence to other measures need to be established for the International Consultation on Incontinence Questionnaire (ICIQ) bladder diary (ICIQ-BD) in the assessment of male lower urinary tract symptoms (LUTS).

OBJECTIVE

To evaluate ICIQ-BD completion rates, frequency, volume, and sensation reporting for men.

DESIGN, SETTING, AND PARTICIPANTS

Baseline data from the Urodynamics for Prostate Surgery Trial; Randomised Evaluation of Assessment Methods (UPSTREAM) randomised controlled trial evaluating 820 men at 26 UK hospitals, looking at the ICIQ-BD, uroflowmetry, International Prostate Symptom Score, and ICIQ symptom score for male LUTS (ICIQ-MLUTS), were assessed.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

The ICIQ-BD, IPSS, ICIQ-MLUTS, and uroflowmetry data at baseline obtained from UPSTREAM were assessed. Correlations were analysed by Pearson's correlation coefficient, and comparison between groups were performed using paired or unpaired t tests or Tukey's test. All statistical tests were two sided and the strength of evidence was presented using p values.

RESULTS AND LIMITATIONS

Of the participants, 25.0% (205/820) provided complete voiding and bedtime information for 3 d, 41.2% (338/820) omitted bedtime information, and the remainder omitted some or all voiding information. Median values (minimum - maximum) of 24-h, daytime, and night-time frequencies were 9.7 (3.3-24.0), 7.7 (3.3-22.7), and 1.7 (0.0-5.7), respectively. The mean voided volume per micturition for day and night times were 175.8 ± 74.2 and 264.4 ± 150.7 ml (p < 0.001), respectively. For fully completed diaries, day- and night-time frequency showed a weak-to-moderate correlation with symptom score questionnaires. More severe nocturia was generally reported in symptom scores than in the ICIQ-BD. In patients with high bother for increased daytime frequency (symptom), the mean daytime frequency (ICIQ-BD) was 9.6 ± 3.2 versus 7.6 ± 2.2 for low bother (p < 0.001). High bother for nocturia showed night-time frequency of 2.3 ± 1.2 versus 1.5 ± 1.1 for low bother (p < 0.001). For fully and partially completed diaries, ICIQ-BD sensation scores correlated weakly with symptom scores. Voided volumes from the bladder diary and uroflowmetry correlated weakly.

CONCLUSIONS

Two-thirds of men (543/820) fully completed voiding information in the ICIQ-BD, but many omitted bedtime information, limiting the ability to quantify nocturia and diagnose nocturnal polyuria.

PATIENT SUMMARY

Most men with urinary symptoms complete a bladder diary fully but may fail to indicate bedtimes. Extra information from a diary helps support symptom questionnaires to explain a patient's urinary habits.

The Challenges of Real-life Bladder Diary Use and Interpretation

The International Consultation on Incontinence Questionnaire bladder diary records the amount and type of drinks, urine output, bladder sensation, and pad use for assessing nocturia and storage urinary symptoms. Instructions before completion, checks after completion, and training of staff in diary analysis are essential.

Can We Rely Solely on the International Prostate Symptoms Score to Investigate Storage Symptoms in Men with Lower Urinary Tract Symptoms Associated with Benign Prostatic Enlargement? Findings from a Cross-sectional Study

BACKGROUND

Discrepancies exist between patient-reported storage phase symptoms severity and International Prostate Symptom Score (IPSS) scores.

OBJECTIVE

To investigate whether the Overactive Bladder questionnaire (OABq) can detect further storage phase lower urinary tract symptoms (LUTS) among patients complaining solely of voiding LUTS based on the IPSS questionnaire, and to address the real-life impact of voiding LUTS towards patients' quality of life (QoL).

DESIGN, SETTING, AND PARTICIPANTS

Data from 233 consecutive men seeking medical help for LUTS/benign prostate enlargement for the first time were analysed. All patients completed both the OABq and the IPSS questionnaire. In order to investigate patients with predominantly voiding phase symptoms, men with storage phase symptoms at IPSS were eventually excluded from the analysis. Patients with an OABq score of ≥40 were considered as those having moderate-to-severe storage LUTS.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

Descriptive statistics and linear regression models tested the associations between OABq scores, IPSS, and IPSS-QoL.

RESULTS AND LIMITATIONS

OABq scores were higher in men with severe voiding symptoms than in men with mild voiding symptoms (p < 0.001). More than half of patients with predominant voiding symptoms, according to the IPSS questionnaire, depicted a pathologic OABq score. A higher rate of pathologic OABq scores was found in men with moderate/severe voiding symptoms than in those with mild scores (67.4% vs 49.6%, p < 0.001). At multivariable analysis, younger age (beta -0.1, p < 0.01), IPSS voiding subscore (beta 0.3, p < 0.001), and OABq score ≥40 (beta 1.1, p < 0.001) emerged as independent predictors of IPSS-QoL after accounting for prostate volume and flow max.

CONCLUSIONS

The OABq can detect the presence of further storage phase LUTS in patients presenting solely with voiding LUTS and IPSS suggestive of voiding phase symptoms. In addition, the OABq was associated with worse patient QoL regardless of the severity of voiding symptoms.

PATIENT SUMMARY

The Overactive Bladder questionnaire (OABq) is able to detect the presence of additional storage lower urinary tract symptoms (LUTS) in patients presenting solely with voiding LUTS according to the IPSS questionnaire. Moreover, the OABq is associated with worse quality of life in these patients regardless of the severity of voiding symptoms.

A general framework for automatic closed-loop control of bladder voiding induced by intraspinal microstimulation in rats

Individuals with spinal cord injury or neurological disorders have problems in voiding function due to the dyssynergic contraction of the urethral sphincter. Here, we introduce a closed-loop control of intraspinal microstimulation (ISMS) for efficient bladder voiding. The strategy is based on asynchronous two-electrode ISMS with combined pulse-amplitude and pulse-frequency modulation without requiring rhizotomy, neurotomy, or high-frequency blocking. Intermittent stimulation is alternately applied to the two electrodes that are implanted in the S2 lateral ventral horn and S1 dorsal gray commissure, to excite the bladder motoneurons and to inhibit the urethral sphincter motoneurons. Asynchronous stimulation would lead to reduce the net electric field and to maximize the selective stimulation. The proposed closed-loop system attains a highly voiding efficiency of 77.2-100%, with an average of 91.28 ± 8.4%. This work represents a promising approach to the development of a natural and robust motor neuroprosthesis device for restoring bladder functions.

Comprehensive Review of Effective Application of Questionnaires for Clinical Research on Lower Urinary Tract Symptoms With Translation and Cultural Adaptation to the Korean Language

Lower urinary tract symptoms are highly prevalent and closely related to patients' quality of life. Clinical research on urologic disease is essential for accumulating evidence on patient management; however, the major obstacle is converting patients' subjective symptoms to objective parameters. The optimal application of well-developed and validated questionnaires is vital in achieving objectivity and minimizing bias in clinical research. Numerous questionnaires for measuring symptoms and quality of life in urologic diseases have been developed worldwide; however, they cannot be directly used in clinical studies without validation processes. This review aimed to explain the common procedures for translation, linguistic, and psychometric validation of developed questionnaires from other languages. Furthermore, we comprehensively reviewed currently available questionnaires for evaluating lower urinary tract symptoms in the Korean population.

A Novel Alternative in the Treatment of Detrusor Overactivity? In Vivo Activity of O-1602, the Newly Synthesized Agonist of GPR55 and GPR18 Cannabinoid Receptors

The aim of the research was to assess the impact of O-1602—novel GPR55 and GPR18 agonist—in the rat model of detrusor overactivity (DO). Additionally, its effect on the level of specific biomarkers was examined. To stimulate DO, 0.75% retinyl acetate (RA) was administered to female rats’ bladders. O-1602, at a single dose of 0.25 mg/kg, was injected intra-arterially during conscious cystometry. Furthermore, heart rate, blood pressure, and urine production were monitored for 24 h, and the impact of O-1602 on the levels of specific biomarkers was evaluated. An exposure of the urothelium to RA changed cystometric parameters and enhanced the biomarker levels. O-1602 did not affect any of the examined cystometric parameters or levels of biomarkers in control rats. However, the O-1602 injection into animals with RA-induced DO ameliorated the symptoms of DO and caused a reversal in the described changes in the concentration of CGRP, OCT₃, BDNF, and NGF to the levels observed in the control, while the values of ERK1/2 and VAChT were significantly lowered compared with the RA-induced DO group, but were still statistically higher than in the control. O-1602 can improve DO, and may serve as a promising novel substance for the pharmacotherapy of bladder diseases.

Italian real-life clinical setting: the persistence and adherence with mirabegron in women with overactive bladder

INTRODUCTION AND HYPOTHESIS

The aims of this study were to evaluate the persistence, the adherence on treatment with mirabegron, the reasons for the interruption in patients with overactive bladder syndrome (OAB) and their satisfaction.

METHODS

This was an Italian multicentre prospective study. Four tertiary urological centers were involved. We included women with no neurogenic OAB symptoms already in therapy with once-daily mirabegron 50 mg for 1 month. They were followed up at 1, 3 and 6 months post-treatment with uroflowmetry with voiding diary for 3 days and post-void residual measurement. They completed self-administered Overactive Bladder questionnaire short form (OABq), Morisky Medication Adherence Scale-4 short form (MMAS), Patient Global Impression-Improvement questionnaire. Patients were divided in OAB wet and OAB dry groups, and in treatment-naive and treatment-experienced groups.

RESULTS

Between January 2018 and July 2018, 80 patients with OAB were included. Fifteen (18.7%) patients continued the treatment for 6 months; 17.5% interrupted the therapy before 1 month: 30% within the third month, while, 33.7% after 1 month. The median time to discontinuation with mirabegron was 62.5 days. The mean adherence was 0.42 ± 0.33, median MMAS was 2 (0-4). The adherence was significantly greater in treatment-naïve (22.4%) than treatment-experienced (6.5%) patients, without statistically significant differences in the different OAB form. The cost is the main cause of interruption of therapy (50% of cases).There was an improvement of OABqSF score and PGI-I score.

CONCLUSION

In Italy, the cost compromises adherence and persistence of therapy with mirabegron despite the good functional outcomes.

Association between the Urinary Bladder Volume and the Incidence of "De Novo" Overactive Bladder in Patients with Stress Urinary Incontinence Subjected to Sling Surgeries or Burch Procedure

Aim. The aim of the study was to compare the incidence of "de novo" overactive bladder (OAB) after sling surgeries and Burch procedure and to analyze the effect of the preoperative bladder volume on the incidence of this condition. Methods. This prospective trial included 290 female patients with stress urinary incontinence (SUI) who were subjected to sling surgeries (TOT or TVT, n=170) or Burch procedure (n=120). Urodynamic testing was performed prior to the surgery and 6 months thereafter. The presence of OAB was diagnosed on the basis of subjective symptoms and urodynamic parameters. Results. The incidence of OAB 3 at 6 months postsurgery was the highest in patients who were subjected to the Burch procedure (14.2% and 17.5%, respectively). The incidence of OAB at 6 months turned out to be significantly higher in patients subjected to the Burch procedure with preoperative bladder volumes greater than 353 ml. We observed the significant postoperative decrease in the bladder volume of women who developed this complication following the Burch procedure. Conclusions. Among surgeries for stress urinary incontinence, Burch procedure is associated with the greatest risk of overactive bladder development. Probably, one reason for the higher incidence of overactive bladder after Burch procedure is the intraoperative reduction of the urinary bladder volume.

Role of the brain stem in tibial inhibition of the micturition reflex in cats

This study examined the role of the brain stem in inhibition of bladder reflexes induced by tibial nerve stimulation (TNS) in α-chloralose-anesthetized decerebrate cats. Repeated cystometrograms (CMGs) were performed by infusing saline or 0.25% acetic acid (AA) to elicit normal or overactive bladder reflexes, respectively. TNS (5 or 30 Hz) at three times the threshold (3T) intensity for inducing toe movement was applied for 30 min between CMGs to induce post-TNS inhibition or applied during the CMGs to induce acute TNS inhibition. Inhibition was evident as an increase in bladder capacity without a change in amplitude of bladder contractions. TNS applied for 30 min between saline CMGs elicited prolonged (>2 h) poststimulation inhibition that significantly (P < 0.05) increased bladder capacity to 30-60% above control; however, TNS did not produce this effect during AA irritation. TNS applied during CMGs at 5 Hz but not 30 Hz significantly (P < 0.01) increased bladder capacity to 127.3 ± 6.1% of saline control or 187.6 ± 5.0% of AA control. During AA irritation, naloxone (an opioid receptor antagonist) administered intravenously (1 mg/kg) or directly to the surface of the rostral brain stem (300-900 μg) eliminated acute TNS inhibition and significantly (P < 0.05) reduced bladder capacity to 62.8 ± 22.6% (intravenously) or 47.6 ± 25.5% (brain stem application). Results of this and previous studies indicate 1) forebrain circuitry rostral to the pons is not essential for TNS inhibition; and 2) opioid receptors in the brain stem have a critical role in TNS inhibition of overactive bladder reflexes but are not involved in inhibition of normal bladder reflexes.

Age-related decrease of adenosine-mediated relaxation in rat detrusor is a result of A2B receptor downregulation

OBJECTIVES

To analyze the effect of adenosine on detrusor smooth muscle contraction and to assess age-related changes of adenosine function.

METHODS

Sustained contractions were induced in young (10-30 days) and old (>60 days) rat detrusor muscle strips by application of 30 mmol/L K(+) and adenosine (0.1-400 µmol/L), which was either applied before raising the K(+) concentration or added to the precontracted muscle strip. Quantitative polymerase chain reaction analyses were used to study adenosine receptor expression in rat and human detrusor specimens.

RESULTS

Pretreatment with adenosine dose-dependently reduced subsequent K(+) -induced contraction in detrusor muscle strips from young rats (half-maximal effect = 40 µmol/L). The residual depolarization-induced contraction strength in young tissue was significantly smaller than in tissue from old animals, showing a greater potency of adenosine in young detrusor samples. Likewise, the relaxing effect of adenosine on precontracted detrusor muscle was also significantly more pronounced in young compared with older detrusor. Quantitative polymerase chain reaction showed an age-related downregulation of the adenosine A2B receptor in rat detrusor tissues, which could be confirmed in human detrusor samples. Furthermore, relaxation of both K(+) -induced as well as carbachol-induced contraction by the specific A2B receptor agonist BAY 60-6583 was significantly more pronounced in young than in old rats.

CONCLUSIONS

Adenosine powerfully counteracts contraction of detrusor smooth muscle, which is lost in the aging bladder. This is paralleled by an age-dependent transcriptional downregulation of the low-affinity A2B receptor. Hence, this might be pathophysiologically relevant in conditions of raised adenosine concentrations, such as hyperactive bladder contractility.

Somatic modulation of spinal reflex bladder activity mediated by nociceptive bladder afferent nerve fibers in cats

The goal of the present study was to determine if supraspinal pathways are necessary for inhibition of bladder reflex activity induced by activation of somatic afferents in the pudendal or tibial nerve. Cats anesthetized with α-chloralose were studied after acute spinal cord transection at the thoracic T9/T10 level. Dilute (0.25%) acetic acid was used to irritate the bladder, activate nociceptive afferent C-fibers, and trigger spinal reflex bladder contractions (amplitude: 19.3 ± 2.9 cmH2O). Hexamethonium (a ganglionic blocker, intravenously) significantly (P < 0.01) reduced the amplitude of the reflex bladder contractions to 8.5 ± 1.9 cmH2O. Injection of lidocaine (2%, 1-2 ml) into the sacral spinal cord or transection of the sacral spinal roots and spinal cord further reduced the contraction amplitude to 4.2 ± 1.3 cmH2O. Pudendal nerve stimulation (PNS) at frequencies of 0.5-5 Hz and 40 Hz but not at 10-20 Hz inhibited reflex bladder contractions, whereas tibial nerve stimulation (TNS) failed to inhibit bladder contractions at all tested frequencies (0.5-40 Hz). These results indicate that PNS inhibition of nociceptive afferent C-fiber-mediated spinal reflex bladder contractions can occur at the spinal level in the absence of supraspinal pathways, but TNS inhibition requires supraspinal pathways. In addition, this study shows, for the first time, that after acute spinal cord transection reflex bladder contractions can be triggered by activating nociceptive bladder afferent C-fibers using acetic acid irritation. Understanding the sites of action for PNS or TNS inhibition is important for the clinical application of pudendal or tibial neuromodulation to treat bladder dysfunctions.

Overactive bladder in cervical spondylotic myelopathy

BACKGROUND

Overactive bladder (OAB) is a new disease concept defined by the International Continence Society in 2002. There have been no reports of OAB among patients with cervical spondylotic myelopathy assessed on the basis of symptom questionnaires.

METHODS

One-hundred-and-six patients diagnosed with cervical spondylotic myelopathy and treated by use of laminoplasty were examined. The patients were classified into two groups, those identified as having OAB (OAB group) and those identified as not having OAB (non-OAB group), by use of the Overactive Bladder Symptom Score collected before and 1 year after surgery. The clinical results for the two groups were assessed. OAB symptom prevalence and post-operative symptom improvement were investigated 1 year postoperatively.

RESULTS

Of the 106 patients, 50 were identified as having OAB (symptom prevalence 47.2%). Of these 50 patients, symptom improvement was observed for only 14 (28%) 1 year after surgery. For both groups good improvement on the basis of the Japanese Orthopedic Association score was observed 1 year postoperatively, but there were no significant differences between them.

CONCLUSIONS

Post-operative improvement of OAB symptoms in cervical spondylotic myelopathy patients was low, which indicated that OAB was most frequently attributable to non-neurogenic and idiopathic, but not neurogenic, causes. It is considered necessary to tell patients with cervical spondylotic myelopathy that the possibility of post-operative OAB symptom improvement is not high when the explanation for informed consent is given before the operation.

Remodeling of the muscle layer (detrusor muscle) of hyperactive bladder disease in patients with benign prostatic hyperplasia

We studied remodeling of the detrusor of hyperactive bladder in patients with benign prostatic hyperplasia. Detrusor remodeling was caused by degenerative and atrophic changes and elimination of smooth muscle cells, compensatory hypertrophy of remaining cells, and diffuse or focal-diffuse replacement fibrosis. Focal or diffuse infiltration of all layers of the detrusor with lymphocytes and plasma cells is an important pathologic feature of hyperactive bladder. These changes correlated with pronounced remodeling of the glandular and fibrotic-muscular layers in the prostate gland. We have identified stereotyped patterns of the intracellular reorganization of smooth muscle cells in the detrusor of hyperactive bladder and in the prostate with benign prostatic hyperplasia, which represent both the compensatory and adaptive reactions (hypertrophied cells with minor ultrastructural changes) and the types of smooth muscle cell injury ("dark" electron-dense cells and "light" cells with pronounced lysis of myofilaments and discomplexation of organelles).

Sex differences in the physiology and pharmacology of the lower urinary tract

Sexual dimorphism is not only noticed in the prevalence of many diseases, but also in multiple physiological functions in the body. This review has summarized findings from published literature on the sex differences of the pathophysiology and pharmacology of the lower urinary tract (LUT) of humans and animals. Sex differences have been found in several key areas of the LUT, such as overactive bladder, expression and function of neurotransmitter receptors in the bladder and urethra, and micturition patterns in humans and animals. It is anticipated that this review will not only evoke renewed interest for further research on the mechanism of sex differences in the pathophysiology of the LUT (especially for overactive bladder), but might also open up the possibilities for gender-based drug development by pharmaceutical industries in order to find separate cures for men and women with diseases of the LUT.

Alteration in TRPV1 and Muscarinic (M3) receptor expression and function in idiopathic overactive bladder urothelial cells

AIM

To examine function of both cholinergic (muscarinic) and TRPV1 receptors in human bladder urothelial (HBUC) from non-neurogenic overactive bladder (OAB) patients as compared to control subjects.

METHODS

Primary HBUC cultures were derived from cystoscopic biopsies from OAB and control subjects. Muscarinic and TRPV1 function was assessed by acetylcholine (5 μm) or capsaicin (0.5 μm) evoked ATP release, measured by luciferase assay. Overall, expression of TRPV1 and muscarinic M3 receptors in bladder urothelial cells was accomplished using western immunoblotting.

RESULTS

Our findings revealed that the response to acetylcholine in OAB HBUC cultures (which was blocked by the nonselective muscarinic antagonist, atropine methyl nitrate or AMN) was not significantly different than from controls. The acetylcholine M3 receptor was slightly decreased as compared to control. In contrast, OAB HBUC cultures exhibited a capsaicin hypersensitivity and augmented release of ATP (3.2 fold higher), which was blocked by the antagonist capsazepine. The increase in capsaicin sensitivity correlated with increased urothelial TRPV1 expression.

CONCLUSION

Though characterized in a small number of subjects, augmented release of urothelial-derived transmitters such as ATP could 'amplify' signalling between and within urothelial cells and nearby afferent nerves.

Effects of kinin B(1) and B(2) receptor antagonists on overactive urinary bladder syndrome induced by spinal cord injury in rats

BACKGROUND AND PURPOSE

Kinin B(1) and B(2) receptors have been implicated in physiological and pathological conditions of the urinary bladder. However, their role in overactive urinary bladder (OAB) syndrome following spinal cord injury (SCI) remains elusive.

EXPERIMENTAL APPROACH

We investigated the role of kinin B(1) and B(2) receptors in OAB after SCI in rats.

KEY RESULTS

SCI was associated with a marked inflammatory response and functional changes in the urinary bladder. SCI resulted in an up-regulation of B(1) receptor mRNA in the urinary bladder, dorsal root ganglion and spinal cord, as well as in B(1) protein in the urinary bladder and B(1) and B(2) receptor protein in spinal cord. Interestingly, both B(1) and B(2) protein expression were similarly distributed in detrusor muscle and urothelium of animals with SCI. In vitro stimulation of urinary bladder with the selective B(1) or B(2) agonist elicited a higher concentration-response curve in the SCI urinary bladder than in naive or sham urinary bladders. Cystometry revealed that treatment of SCI animals with the B(2) selective antagonist icatibant reduced the amplitude and number of non-voiding contractions (NVCs). The B(1) antagonist des-Arg(9) -[Leu(8) ]-bradykinin reduced the number of NVCs while the non-peptide B(1) antagonist SSR240612 reduced the number of NVCs, the urinary bladder capacity and increased the voiding efficiency and voided volume.

CONCLUSIONS AND IMPLICATIONS

Taken together, these data show the important roles of B(1) and B(2) receptors in OAB following SCI in rats and suggest that blockade of these receptors could be a potential therapeutic target for controlling OAB.

Management of lower urinary tract dysfunction in patients with neurological disorders

The proper performance of the lower urinary tract is dependent on an intact neural innervation of the individual structures involved. Therefore, any congenital neurological anomalies, diseases, or lesions of the central, peripheral, or autonomic nervous systems can result in lower urinary tract symptoms. Lower urinary tract dysfunction (LUTD) secondary to neurological disorders can significantly reduce quality of life (QoL) and may also give rise to serious complications and psychological and social sequelae. The goals of management of LUTD in patients with neurological disorders are to prevent serious complications and to improve the patient's QoL. Understanding the physiology and pathophysiology of micturition is critical to selecting appropriate treatment options. This article provides an overview of the clinical characteristics, diagnosis, and management of LUTD in patients with certain central and peripheral neuropathies and common lesions.

Persistence with prescribed antimuscarinic therapy for overactive bladder: a UK experience

Study Type--Therapy (prevalence) Level of Evidence 2b. What's known on the subject? and What does the study add? Persistence with long-term medication in chronic diseases is typically low and that for overactive bladder medication is lower than average. Sub-optimal persistence is a major challenge for the successful management of overactive bladder. Using UK prescription data, persistence was generally low across the range of antimuscarinics. Patients aged 60 years and above were more likely to persist with prescribed oral antimuscarinic drugs than younger patients (40-59 years). Solifenacin was consistently associated with the highest rate of persistence compared with the other antimuscarinics included in the study

OBJECTIVES

• To describe the level of persistence for patients receiving antimuscarinics for overactive bladder (OAB) over a 12-month period based on real prescription data from the UK. • To investigate patterns of persistence with oral antimuscarinic drugs prescribed for OAB, across different age groups.

PATIENTS AND METHODS

• UK prescription data from a longitudinal patient database were analysed retrospectively to assess persistence with darifenacin, flavoxate, oxybutynin (extended release [ER] and immediate release [IR]), propiverine, solifenacin, tolterodine (ER/IR) and trospium. • Data were extracted from the medical records of >1,200,000 registered patients via general practice software, and anonymized prescription data were collated for all eligible patients with documented OAB (n = 4833). • Data were collected on patients who started treatment between January 2007 and December 2007 and were collected up to December 2008, to allow each patient a full 12-month potential treatment period. Failure of persistence was declared after a gap of at least 1.5 times the length of the period of the most recent prescription. • The analysis included only patients who were new to a course of treatment (i.e. who had not been prescribed that particular treatment or dosage for at least 6 months before the study period).

RESULTS

• The number of patients prescribed each antimuscarinic drug varied from 23 for darifenacin to 1758 for tolterodine ER. • The longest mean persistence was reported for solifenacin (187 days versus 77-157 days for the other treatments). • At 3 months, the proportions of patients still on their original treatment were: solifenacin 58%, darifenacin 52%, tolterodine ER 47%, propiverine 47%, tolterodine IR 46%, oxybutynin ER 44%, trospium 42%, oxybutynin IR 40%, flavoxate 28%. • At 12 months, the proportions of patients still on their original treatment were: solifenacin 35%, tolterodine ER 28%, propiverine 27%, oxybutynin ER 26%, trospium 26%, tolterodine IR 24%, oxybutynin IR 22%, darifenacin 17%, flavoxate 14%. • In a sub-analysis stratified by age, patients aged ≥ 60 years were more likely to persist with prescribed therapy over the 12-month period than those aged <60 years.

CONCLUSIONS

• Twelve months after the initial prescription, persistence rates with pharmacotherapy in the context of OAB are generally low. • Solifenacin was associated with higher levels of persistence compared with other prescribed antimuscarinic agents. • Older people are more likely than younger patients to persist with prescribed therapy. Further studies are required to understand this finding and why patients are more likely to persist with one drug rather than another.

Standard Pharmacological Treatment and New Therapies for Overactive Bladder

The prevalence of overactive bladder (OAB) in adult males varies from 10.2% to 17.4%, and in females from 7.7 to 31.3. 16.5% of the adult population presents symptoms consistent with OAB; of these, 37.2% are actually affected. The OAB has a significant effect on the quality of life. Initial treatment includes behavioral therapy, physiotherapy and antimuscarinic drugs. In patients where behavioral modifications fail, treatment is associated with antimuscarinics. The antimuscarinic agents used to treat OAB showed some efficacy, but adverse events too, such as dry mouth, constipation, headache and blurred vision. In selected cases unresponsive to antimuscarinic therapy, it is possible to use second-line treatments represented by sacral neuromodulation and botulinum toxin type A both for idiopathic detrusor overactivity, where it is still an experimental treatment, and for neurogenic cases with 2011 FDA approval. Surgical options represent the last choice for selected cases.

Electrical nerve stimulation for overactive bladder in children

Overactive bladder (OAB) is a urological condition that is frequently observed in children and requires treatment. Standard urotherapy is usually the first line of treatment; however, children with severe OAB do not respond to this therapy. Antimuscarinic drugs may be used, but complete resolution of symptoms with this medication is low. Studies, including two randomized clinical trials, have demonstrated that electrical nerve stimulation (ENS) can be used successfully for OAB in children. Electrodes have been placed in the genitals, anus, and intravesical area, and on the tibial posterior nerve, as well as used transcutaneously or implanted during a surgical procedure. This Review will discuss the use of ENS in children with OAB, with particular focus on the putative mechanisms of action, the different ENS techniques available, and clinical results for this therapy.