Bladder underactivity

Brazilian Portuguese translation, cross-cultural adaptation, and content validation of the pediatric lower urinary tract symptom score

BACKGROUND

Early screening instruments for professionals are important to reduce the cost and time of diagnosing pediatric lower urinary tract dysfunction. This study aimed to translate, cross-culturally adapt, and validate pediatric lower urinary tract symptom scores.

METHODS

This methodological study was conducted in 2019 in two phases: translation and cross-cultural adaptation, and content validation. In the first phase, we used translators, specialists, and 30 parents of children with voiding dysfunction. In the second phase, validation was performed by 11 pediatric urology specialists.

FINDINGS

The instrument was translated and adapted to Brazilian Portuguese and presented an excellent level of verbal comprehension. Further, the instrument presented a good content validity index >0.8 for all items, except for the nomenclature and clarity of two items, as indicated by the Cronbach's alpha value of 0.75 for internal consistency.

DISCUSSION

The final version showed semantic, idiomatic, experiential, and conceptual equivalence with the original instrument, indicating that it is adequate for other assessments of psychometric qualities.

PRACTICE IMPLICATIONS

The translation and adaptation of an important instrument for diagnosing lower urinary tract dysfunction in children to other countries helps nurses identify the disease early and monitor the treatment.

Therapeutic effects of silodosin and urapidil on underactive bladder associated with diabetic cystopathy

OBJECTIVES

Pharmacological treatment options for underactive bladder (UAB) syndrome are limited. Urapidil is the only alpha₁ -adrenoceptor (AR) antagonist that can be used for urinary disorders in women in some countries. However, no studies have directly verified the effects of alpha₁ -AR antagonists on the female urethra and UAB-like dysfunctions. We investigated the effects of silodosin (alpha_1A -AR antagonist) and urapidil (nonselective alpha₁ -AR antagonist) on the voiding function in female rats with diabetes mellitus (DM).

METHODS

Changes in intraurethral pressure (IUP) induced by midodrine (alpha₁ -AR agonist) and mean blood pressure (MBP) were continuously measured in normal female rats to verify the pharmacological profiles of the drugs. To establish a DM model, rats were administered streptozotocin (STZ; 50 mg/kg, intravenous). Eight weeks after STZ administration, drugs were subcutaneously delivered through an osmotic pump. Four weeks after drug administration, emptied bladder blood flow (BBF), intravesical pressure, and the micturition volume were measured.

RESULTS

Both silodosin and urapidil inhibited the midodrine-induced increase in IUP and decreased MBP in a dose-dependent manner. Silodosin had a more substantial effect on the lower urinary tract than on MBP. Twelve weeks after STZ administration, DM rats exhibited UAB-like dysfunction (increased bladder capacity/bladder weight and residual volume and decreased bladder voided efficiency) and decreased BBF. Both drug treatments controlled this dysfunction.

CONCLUSIONS

Alpha₁ -AR antagonists induced dose-dependent urethral relaxation in female rats. These drugs ameliorated UAB-like dysfunction in STZ-induced DM rats. In addition, alpha_1A -AR antagonists such as silodosin, which have limited effects on blood pressure, appear to be useful for treating UAB.

Clinical features of detrusor underactivity in elderly men without neurological disorders

OBJECTIVES

To investigate the clinical features of detrusor underactivity (DU) in elderly men without neurological disorders.

METHODS

A total of 336 men aged ≥50 years without neurogenic disorders who underwent pressure flow studies and who had DU or bladder outlet obstruction (BOO) were reviewed retrospectively. According to the bladder contractility index (BCI) and the BOO index (BOOI), the subjects were classified into the following three groups: (a) pure DU group, BCI < 100 and BOOI < 40; (b) DU + BOO group, BCI < 100 and BOOI ≥ 40; and (c) pure BOO group, BCI ≥ 100 and BOOI ≥ 40. Subjective and objective parameters were compared among the three groups, and the predictors for pure DU were evaluated by multivariate analysis.

RESULTS

Of the 336 patients, 205 who met the study criteria were included in the analysis: 63 (30.7%) with pure DU, 48 (23.4%) with DU + BOO, and 94 (45.9%) with pure BOO. The proportion of the pure DU group increased with increasing age. Prostate volume was the lowest in the pure DU group. Frequency, urgency on the International Prostate Symptom Score (IPSS), and the IPSS storage subscore were the lowest in the pure DU group. Multivariate analysis showed that age (odds ratio [OR] 1.114 [95% CI, 1.032-1.203], P = .005), prostate volume (OR 0.968 [95% CI, 0.949-0.987], P = .001), and urgency (OR 0.623 [95% CI, 0.431-0.900], P = .012) were predictors of pure DU.

CONCLUSION

Older age, smaller prostate volume, and less urgency may be clinical features of pure DU.

Detrusor underactivity prevalence and risk factors according to different definitions in women attending urogynecology clinic

INTRODUCTION AND HYPOTHESIS

There is still no consensus on definitions of detrusor underactivity; therefore, it is difficult to estimate the prevalence. The primary objective of the study was to evaluate the prevalence of detrusor underactivity in a cohort of patients with pelvic floor disorders according to different proposed urodynamics definitions. The secondary objectives were to estimate the association between detrusor underactivity and symptoms, anatomy and urodynamic findings and to build predictive models.

METHODS

Patients who performed urodynamic evaluation for pelvic floor disorders between 2008 and 2016 were retrospectively analyzed. Detrusor underactivity was evaluated according to Schafer's detrusor factor, Abrams' bladder contractility index and Jeong cut-offs. The degree of concordance between each method was measured with Cohen's kappa, and differences were tested using Student's t test, Wilcoxon test and Pearson's chi-squared test.

RESULTS

The prevalence of detrusor underactivity among a cohort of 2092 women, concerning the three urodynamic definitions, was 33.7%, 37.0% and 4.1%, respectively. Age, menopausal status, voiding/bulging symptoms, anterior and central prolapse, first desire to void and positive postvoid residual were directly related to detrusor underactivity. Conversely, stress urinary incontinence, detrusor pressures during voiding and maximum flow were inversely associated. Final models for detrusor underactivity resulted in poor accuracy for all considered definitions.

CONCLUSIONS

The prevalence of detrusor underactivity varies depending on the definition considered. Although several clinical variables resulted as independent predictors of detrusor underactivity, instrumental evaluation still plays a key role in the diagnosis.

Age-related reductions in the excitability of phasic dorsal root ganglion neurons innervating the urinary bladder in female rats

Previous studies have revealed an impairment in bladder sensory transduction in aged animals. To examine the contributions of electrical property changes of bladder primary afferents to this impairment, we compared the electrical properties of dorsal root ganglion (DRG) neurons innervating the bladder among young (3 months), middle-aged (12 months), and old (24 months) female rats. The DRG neurons were labeled using axonal tracing techniques. Whole-cell current-clamp recordings of small and medium-sized neurons were performed to assess their passive and active properties. Two patterns of firing were identified based on responses to super-threshold stimuli (1.5, 2.0, 2.5, and 3.0 × rheobase): tonic neurons fired more action potentials (APs), whereas phasic neurons fired only one AP at the onset of stimulus. Tonic neurons were smaller and had a slower rate of AP rise, longer AP duration, more depolarized voltage threshold, and greater rheobase than phasic neurons. In phasic neurons, there was an age-associated increase in voltage threshold and an increase of rheobase (P < 0.05), suggesting an age-related decrease in excitability. In addition, both middle-aged and old rats had longer AP durations and slower rates of AP rise than young rats (P < 0.05). In tonic neurons, old rats had a greater AP overshoot and greater rate of AP rise, but no age-associated changes were identified in any other electrical properties. Our results suggest that the electrical properties of tonic and phasic bladder afferents are differentially altered with aging. A decrease in excitability may contribute to age-related reductions in bladder sensory function.

Reduced bladder responses to capsaicin and GSK-1016790A in retired-breeder female rats with diminished volume sensitivity

Literature documents an age-related reduction of bladder sensory function. Transient receptor potential vanilloid (TRPV)1 or TRPV4 channels have been implicated in bladder mechanotransduction. To investigate contributions of TRPV1 or TRPV4 to the age-related reduction of bladder sensory function, bladder responses to capsaicin (CAP; TRPV1 agonist) and GSK-1016790A (GSK; TRPV4 agonist) in retired breeder (RB; 12-15 mo) and young adult (2-3 mo) female rats were compared using multiple methods. Metabolic cage and continuous infusion cystometry [cystometrogram (CMG)] recordings revealed that RB rats exhibit larger bladder capacity and lower voiding frequency. RB rats also have a greater intravesical pressure threshold for micturition; however, the voiding contraction strength was equivalent to that in young rats. CAP (1 μM) or GSK (20 nM) administered intravesically evoked smaller changes in all CMG parameters in RB rats. In vitro, CAP (1 μM) or GSK (20 nM) evoked smaller enhancement of bladder strip contractions, while the muscarinic receptor agonist carbachol (at 100, 300, and 1,000 nM) elicited greater amplitude contractions in RB rats. Patch-clamp recording revealed smaller CAP (100 nM) induced inward currents in bladder primary sensory neurons, and Ca²⁺ imaging revealed smaller GSK (20 nM) evoked increases in intracellular Ca²⁺ concentration in urothelial cells in RB rats. These results suggest that RB rats have a decreased bladder sensory function commonly observed in elderly women, and could be used as an animal model to study the underling mechanisms. Reduced functional expression of TRPV1 in bladder afferents or reduced functional expression of urothelial TRPV4 may be associated with the diminished sensory function.

Characterization of voiding function and structural bladder changes in a rat model of neurogenic underactive bladder disease

OBJECTIVES

To create an animal model for neurogenic underactive bladder disease (UAB) and identify markers to describe secondary myogenic changes in the bladder wall.

MATERIALS AND METHODS

Male rats underwent either bilateral pelvic nerve injury or sham surgery. Four weeks after surgery functional evaluation was performed and tissue was harvested. Functional evaluation consisted of analysis of voiding pattern, 24-h urine collection in a metabolic cage, in vivo cystometry and in-vitro contractile function assessment. PCR and immunohistochemical localization of different smooth muscle cell and extracellular matrix markers was performed on bladder strips.

RESULTS

After pelvic nerve injury, dry bladder weight increased and voiding contractions were absent, resulting in overflow incontinence. In-vitro contractile response to carbachol was decreased. This was paired with an upregulation of synthetic smooth muscle cell (SMC) markers mRNA expression such as retinol binding protein 1 (RBP1), myosin 10 (MYH10) and osteopontin (OPN), and a downregulation of contractile SMC marker smoothelin (SMTL). The SMTL/OPN mRNA ratio was 50 times higher in sham bladders compared to PNI bladders.

CONCLUSIONS

The loss of in-vivo and in-vitro contractile function following pelvic nerve transection is characterized by a switch from a contractile to synthetic SMC phenotype, which is best characterized by the ratio SMTL/OPN mRNA expression. Modulating this phenotypical switch is a potential target for the development of UAB therapy. We suggest for the first time a set of markers that may be useful to evaluate therapeutic strategies on improvements in bladder wall structure.

Pathophysiology of the underactive bladder

Underactive bladder (UAB), which has been described as a symptom complex suggestive of detrusor underactivity, is usually characterized by prolonged urination time with or without a sensation of incomplete bladder emptying, usually with hesitancy, reduced sensation on filling, and slow stream often with storage symptoms. Several causes such as aging, bladder outlet obstruction, diabetes mellitus, neurologic disorders, and nervous injury to the spinal cord, cauda equine, and peripheral pelvic nerve have been assumed to be responsible for the development of UAB. Several contributing factors have been suggested in the pathophysiology of UAB, including myogenic failure, efferent and/or afferent dysfunctions, and central nervous system dysfunction. In this review article, we have described relationships between individual contributing factors and the pathophysiology of UAB based on previous reports. However, many pathophysiological uncertainties still remain, which require more investigations using appropriate animal models.

Alpha1A-adrenoceptor antagonist improves underactive bladder associated with diabetic cystopathy via bladder blood flow in rats

Background

Patients with diabetes experience lower urinary tract symptoms. Cystopathy may evolve into underactive bladder (UAB), depending on the degree and duration of the symptoms. In the present study, we aimed to investigate the effects of silodosin, an alpha_1A-adrenoceptor (AR) antagonist, on UAB in a rat model of diabetes mellitus (DM).

Methods

Female Sprague-Dawley rats (6 weeks old) were administered streptozotocin (STZ) (50 mg/kg, i.v.) to establish a DM model. One week after STZ administration, vehicle or silodosin (0.3 or 1 mg/kg/day) was delivered subcutaneously through an osmotic pump. Nine weeks after STZ administration (8 weeks after drug treatment), a catheter was implanted into the bladder under urethane anesthesia. After the measurement of emptied bladder blood flow (BBF), saline was continuously infused into the bladder and intravesical pressure and micturition volume were measured. In another experiment, the bladder was isolated and nerve markers were quantified.

Results

A cystometrogram showed that bladder capacity (BC), residual volume (RV), and bladder extension (BC/bladder weight) increased by 7.43, 10.47, and 3.59 times, respectively, in vehicle rats in comparison with normal rats. These findings suggested the occurrence of UAB-like symptoms in this model. Silodosin (1 mg/kg/day) inhibited the increase in BC and RV by 49.0% and 46.8%, respectively, and caused a decrease in BBF of approximately 25.5% (when the difference between normal and vehicle was set as 100%) in STZ rats. The nerve marker expression levels tended to be decreased in the bladders of STZ rats and these effects were ameliorated by silodosin.

Conclusions

The STZ rats showed increased bladder extension and RV, symptoms that were suggestive of UAB, and these symptoms were ameliorated by silodosin. These results suggested that the alpha_1A-AR antagonist would be useful for the prevention or treatment of UAB.

Progressive changes in detrusor function and micturition patterns with chronic bladder ischemia

Purpose

Lower urinary tract symptoms (LUTS) are bothersome constellation of voiding symptoms in men and women as they age. Multiple factors and comorbidities are attributed to this problem but underlying mechanisms of nonobstructive nonneurogenic detrusor overactivity, detrusor underactivity and LUTS remain largely unknown. Our goal was to characterize detrusor function and voiding patterns in relation to muscarinic receptors expression, nerve fiber density, and neural ultrastructure in chronic bladder ischemia.

Materials and Methods

Iliac artery atherosclerosis and bladder ischemia were produced in male Sprague-Dawley rats. At 8 and 16 weeks after ischemia, micturition patterns and cystometrograms were recorded in conscious rats then bladder blood flow and nonvoiding spontaneous contractions were measured under general anesthesia. Bladder tissues were processed for Western blotting, immunostaining, and transmission electron microscopy.

Results

Bladder responses to ischemic insult depended on the duration of ischemia. Micturition patterns and cystometric changes at 8-week ischemia suggested detrusor overactivity, while voiding behavior and cystometrograms at 16-week ischemia implied abnormal detrusor function resembling underactivity. Upregulation of muscarinic M2 receptor was found after 8- and 16 weeks of ischemia. Downregulation of M3 and upregulation of M1 were detected at 16-week ischemia. Neural structural damage and marked neurodegeneration were found after 8 and 16 weeks of ischemia, respectively.

Conclusions

Prolonged ischemia may be a mediating variable in progression of overactive bladder to dysfunctional patterns similar to detrusor underactivity. The mechanism appears to involve differential expression of M1, M2, and M3 receptors, neural structural injury, and progressive loss of nerve fibers.

Relationship between urodynamic patterns and lower urinary tract symptoms in Chinese women with a non-neurogenic bladder

Objective

To investigate the urodynamic study (UDS) patterns, obstruction status, continence status, and their correlations among neurologically intact women with lower urinary tract symptoms (LUTS) through an epidemiological and logistic regression analyses.

Methods

We retrospectively analyzed the UDS data of 3265 neurologically intact women with LUTS (2002–2014). Five UDS patterns were identified: normo-active detrusor/sphincter (NA, or DSI, detrusor/sphincter intact), idiopathic detrusor overactivity (IDO), idiopathic sphincter overactivity (ISO), IDO + ISO, and detrusor underactivity (DUA). Analyses of UDS pattern distribution and stratification were performed (based on a modification of the European Urological Association-Madersbacher classification system), and their correlations with bladder outlet obstruction (BOO) and stress urinary incontinence (SUI) status were evaluated via logistic regression analysis.

Results

NA, IDO, IDO + ISO, ISO, and DUA were noted in 927 (28.4%), 678 (20.8%), 320 (9.8%), 689 (21.1%), and 651 (19.9%) cases, respectively. Moreover, storage, storage + voiding, and voiding symptoms were noted in 62.4%, 21.1%, and 16.5% cases, respectively, whereas BOO and SUI were observed in 12.1% and 29.0% cases, respectively. The risk factors for BOO included NA, IDO, ISO, and IDO + ISO, whereas the protective factors against BOO included storage symptoms, SUI, storage + voiding symptoms, and complaint duration within 1–12 months. NA was the only risk factor for SUI, whereas BOO, storage + voiding symptoms, IDO, and storage symptoms were protective factors for SUI.

Conclusion

Five UDS patterns were identified among neurologically intact women with LUTS. Functional abnormalities of the detrusor and/or sphincter were the main causes of LUTS, and were correlated with the BOO or SUI status. Thus, the UDS pattern can provide additional information regarding the risk factors for BOO or SUI status, as compared to symptomatic typing.

Underactive Bladder: Clinical Features, Urodynamic Parameters, and Treatment

Purpose:

Underactive bladder is a complex clinical condition that remains poorly understood due to limited literature. This study aimed to determine its prevalence among patients with voiding dysfunction, presenting symptoms, risk factors, urodynamic findings, and ongoing treatment.

Methods:

A retrospective chart review of consecutive urodynamic studies performed on voiding dysfunction between 2012 and 2014 was conducted to identify patients with detrusor underactivity. Detrusor underactivity was defined by a bladder contractility index of less than 100. Charts and urodynamic tracings were examined for patient demographics, suspected risk factors, presenting symptoms, urodynamic parameters, and treatment undertaken. Descriptive statistics were utilized to analyze the data.

Results:

The prevalence of detrusor underactivity in this study was 23% (79 of 343). Average age of the patients was 59.2 years (range, 19–90 years). Women represented 68.4% (54 of 79) of the patients. The most common reported symptoms were urinary urgency (63.3%), weak stream (61.0%), straining (57.0%), nocturia (48.1%), and urinary frequency (46.8%). Prior pelvic surgery and prior back surgery were noted in 40.5% and 19.0% of the patients, respectively. The most common management was intermittent self-catheterization in 54.4%, followed by observation/conservative treatment in 25.3% and sacral neuromodulation in 12.7%.

Conclusions:

Although underactive bladder is a common condition, its precise diagnosis and treatment remain a challenge. Its symptoms significantly overlap with those of other bladder disorders, and hence, urodynamic evaluation is particularly useful in identifying patients with impaired detrusor contractility. This will help prevent mismanagement of patients with surgery or medical therapy, as that may worsen their condition. Much work needs to be done to better understand this condition and establish optimal management of patients.

Transcutaneous interferential electrical stimulation for the management of non-neuropathic underactive bladder in children: a randomised clinical trial

OBJECTIVES

To assess the efficacy of transcutaneous interferential electrical stimulation (IFES) and urotherapy in the management of non-neuropathic underactive bladder (UAB) in children with voiding dysfunction.

PATIENTS AND METHODS

In all, 36 children with UAB without neuropathic disease [15 boys, 21 girls; mean (sd) age 8.9 (2.6) years] were enrolled and then randomly allocated to two equal treatment groups comprising IFES and control groups. The control group underwent only standard urotherapy comprising diet, hydration, scheduled voiding, toilet training, and pelvic floor and abdominal muscles relaxation. Children in the IFES group likewise underwent standard urotherapy and also received IFES. Children in both groups underwent a 15-session treatment programme twice a week. A complete voiding and bowel habit diary was completed by parents before, after treatment, and 1 year later. Bladder ultrasound and uroflowmetry/electromyography were performed before, at the end of treatment course, and at the 1-year follow-up.

RESULTS

The mean (sd) number of voiding episodes before treatment was 2.6 (1) and 2.7 (0.76) times/day in the IFES and control groups, respectively, which significantly increased after IFES therapy in IFES group, compared with only standard urotherapy in the control group [6.3 (1.4) vs 4.7 (1.3) times/day, P < 0.002). The mean (sd) bladder capacity before treatment was 424 (123) and 463 (121) mL in the control and IFES groups, respectively, which decreased significantly at 1 year after treatment in the IFES group compared with the controls, at 227 (86) vs 344 (127) mL (P < 0.01). Maximum urine flow increased and voiding time decreased significantly in the IFES group compared with controls at the end of treatment sessions and 1 year later (P < 0.05). All the children had abnormal flow curves at the beginning of the study. The flow curve became normal in 14/18 (77%) of the children in the IFES group and six of 18 (33%) in the control group by the end of follow-up (P < 0.007). At the end of the treatment course, night-time wetting was improved in all children who had this symptom before the treatment in the IFES group (P < 0.01).

CONCLUSION

Combining IFES and urotherapy is a safe and effective therapy in the management of children with UAB.