Variability of post-void residual urine volume and bladder voiding efficiency in patients with underactive bladder

Can we define the optimal postvoid residual volume at which intermittent catheterization should be recommended, and are there other measures that could guide an intermittent catheterization protocol: ICI-RS 2023

AIMS

The postvoid residual (PVR) volume of urine in the bladder is widely used in clinical practice as a guide to initiate treatment, including clean-intermittent self-catheterization (CISC). It is often believed that an elevated PVR causes complications such as recurrent urinary tract infections (UTI) and renal failure. However, evidence for this is limited and identifying alternative measures to guide treatment decisions may optimize patient care. At the International Consultation on Incontinence Research Society (ICI-RS) meeting in 2023 a Think Tank addressed the question of whether we can define the optimal PVR at which CISC should be recommended, and whether there are other measures that could guide a CISC protocol.

METHODS

The Think Tank conducted a literature review and expert consensus meeting focusing on current limitations in defining and measuring PVR, and highlighting other measures that may optimize selection for, and persistence with, CISC.

RESULTS

There is no consensus on the threshold value of PVR that is considered "elevated" or "significant." There is a lack of standardization on terminology, and the normal range of PVR in different populations of different ages remains to be well-studied. The measurement of PVR is influenced by several factors, including intraindividual variation, timing and method of measurement. Furthermore, the evidence linking an elevated PVR with complications such as UTI and renal failure is mixed. Other measures, such as bladder voiding efficiency or urodynamic parameters, may be better at predicting such complications, and therefore may be more relevant at guiding a CISC protocol.

CONCLUSIONS

There is a lack of high quality evidence to support PVR as a predictor for complications of UTI or renal failure. Threshold values for normal PVR in different populations are unknow, and so threshold values for "elevated" or "significant" PVR cannot be determined. Other factors, such as urodynamic findings, may be better at predicting complications and therefore guiding management decisions, and this remains to be studied. Areas for further research are proposed.

Voiding efficiency: a predictor of failed trial off catheter after transurethral resection of prostate

PURPOSE

Following transurethral resection of the prostate (TURP), there is no clear recommendation for the catheter duration, and objective criteria are needed to determine appropriate time for trial off catheter. Current study is aimed to identify the high-risk patients for failed trial off catheter and the association with preoperative voiding efficiency with postoperative failed trial without catheter.

METHODOLOGY

This is cross-sectional single institutional study. All eligible patients who underwent TURP were followed preoperatively for symptoms and workup, including voiding efficiency based on ultrasound findings, intraoperatively for resection parameters, and postoperatively for a trial off a catheter. All the findings were documented, and the data were analyzed on SPSS(TM) 22. Demographic variables were calculated in the form of frequency and percentages. The association of voiding efficiency with failed trials off catheters was checked through Chi-square and binary logistic regression analysis.

RESULTS

132 patients were included in the study. The mean voiding efficiency was 57.5%. Based on voiding efficiency cut off, of 50%, patients were divided into two groups. The association between voiding efficiency and failed trials off catheters was not found to be statistically significant, with a p value of 0.79. Only prevoid volume, postvoid volume, duration of symptoms, and upper tract damage were found to be statistically significant predictors of failed trial off catheter, with a p value of < 0.05.

Novel clinical diagnostic criteria based on noninvasive examination findings to predict the presence of urodynamic detrusor underactivity in men

AIMS

To investigate the usefulness of novel clinical diagnostic criteria based on noninvasive examination findings to diagnose urodynamic detrusor underactivity (DU) in men.

METHODS

We developed clinical diagnostic criteria to predict the presence of urodynamic DU in men as follows: (a) bladder voiding efficiency <70% on uroflowmetry, (b) existence of "sawtooth and interrupted waveforms" on uroflowmetry, and (c) ultrasonography-documented intravesical prostatic protrusion <10 mm. We analyzed the sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of these clinical criteria for diagnosing urodynamic DU in men aged 50 years or above with lower urinary tract symptoms who underwent urodynamic studies.

RESULTS

Of the 314 men analyzed (mean age, 72.4 years; mean detrusor contraction index [DCI], 98.8; and mean bladder outlet obstruction index [BOOI], 43.9), 89 men met this clinical DU diagnostic criteria. Of these, 79 men (88.8%) had urodynamic DU (DCI < 100 and BOOI < 40), nine (10.1%) had DU + BOO (DCI < 100 and BOOI ≥ 40), and one (1.1%) had normal voiding functions. None of the men with urodynamic BOO (DCI ≥ 100 and BOOI ≥ 40) met the clinical DU diagnostic criteria. The sensitivity, specificity, PPV, and NPV of these clinical diagnostic criteria for urodynamic DU were 69.3%, 95.0%, 88.8%, and 84.4%, respectively.

CONCLUSION

The proposed clinical DU diagnostic criteria showed a high PPV (88.8%) for diagnosing urodynamic DU. None of the patients with BOO met the clinical diagnostic criteria for DU. These clinical DU diagnostic criteria may be useful in identifying men with urodynamic DU in clinical practice.

The epidemiology of male lower urinary tract symptoms associated with benign prostatic hyperplasia: Results of 20 years of Korean community care and surveys

PURPOSE

To investigate the prevalence of lower urinary tract symptoms/benign prostatic hyperplasia in a Korean population.

MATERIALS AND METHODS

The Korean Prostate & Voiding Health Association provided free prostate-related community health care and conducted surveys in all regions of Korea from 2001 to 2022 with the cooperation of local government public health centers. A total of 72,068 males older than 50 were surveyed and analyzed. History taking, International Prostate Symptom Score (IPSS), transrectal ultrasonography, prostate-specific antigen (PSA) testing, uroflowmetry, and urine volume testing were performed.

RESULTS

The mean prostate volumes in males in their 50s, 60s, 70s, and 80s or above were 24.7 g, 27.7 g, 31 g, and 33.7 g, respectively. The proportion of males with high PSA greater than 3 ng/mL was 3.8% among males in their 50s, 7.7% among males in their 60s, 13.1% among males in their 70s, and 17.9% among males 80 years of age or older. The mean IPSS total scores in males in their 50s, 60s, 70s, and 80s or above were 10.7, 12.7, 14.5, and 16, respectively. Severe symptoms were reported by 27.3% of males, whereas 51.7% reported moderate symptoms. The mean Qmax in males in their 50s, 60s, 70s, and 80s or above were 20 mL/s, 17.4 mL/s, 15.4 mL/s, and 13.8 mL/s, respectively.

CONCLUSIONS

In this population-based study, mean prostate volume, IPSS, PSA, and Qmax were 30.6±15.1 g, 14.8±8.2, 1.9±4.7 ng/mL, and 15.6±6.5 mL/s, respectively. Aging was significantly associated with increased prostate volume, PSA levels, and IPSS scores, and with decreased Qmax and urine volume.

To Explore the Diagnostic Value of Bulbocavernosus Muscle Reflex and Pudendal Somatosensory Evoked Potentials for Diabetic Neurogenic Bladder

Objective

To explore the diagnostic value of bulbocavernosus muscle reflex and pudendal somatosensory evoked potentials for diabetic neurogenic bladder.

Methods

From January 2021 to December 2021, 104 patients with type 2 diabetes mellitus admitted to the hospital were recruited, with 57 allocated to the case group and 47 to the control group. Outcome measures included bulbocavernosus muscle response, pudendal somatosensory evoked potentials, and bladder residual urine volume. The connection of bulbocavernosus muscle response and pudendal somatosensory evoked potentials with bladder residual urine volume was investigated using the Pearson analysis.

Results

In both males and females, the latency of the left and right bulbocavernosus muscle reflexes in the case group was longer than in the control group, but the difference was not statistically significant (P > 0.05), and the wave amplitude of the left and right bulbocavernosus muscle reflexes was significantly smaller than that of the control group (P < 0.05). The diabetic neurogenic bladder was associated with a significantly longer latency and a smaller wave amplitude of pudendal somatosensory evoked potentials versus without neurogenic bladder (P < 0.05). Patients with a diabetic neurogenic bladder had more residual bladder urine volume versus those without (P < 0.05). Bladder residual urine volume was significantly positively correlated with bulbocavernosus muscle reflex and pudendal somatosensory evoked potential latency and negatively correlated with wave amplitude (P < 0.05).

Conclusion

The bulbocavernosus muscle reflex and pudendal somatosensory evoked potentials demonstrate great potential as adjuncts to diagnose diabetic neurogenic bladder and correlate with ultrasound results in determining bladder function in patients.

Activation of the TGF-β1/Smads/α-SMA pathway is related to histological and functional changes in children with neurogenic bladder

This research is to investigate the expression of the TGF-β1/Smads/α-SMA pathway and its effect on bladder histology and function in children with neurogenic bladder (NB). The bladder specimens from 10 children with NB and 8 children with vesicoureteral junction obstruction were collected into the NB and control groups. The expression of TGF-β1, Smad2, Smad3, Smad4, Smad6, α-SMA, fibronectin, collagen I and collagen III in bladder tissues was detected. In addition, the histological characteristics of the bladder were evaluated. A preoperative urodynamic study was performed on all children with NB. We analysed the correlations among the expression of the marker protein a-SMA in myofibroblasts, effector cells of the pathway, and bladder function parameters. Compared with those in the control group, the expression of TGF-β1, Smad2, Smad3, Smad4, α-SMA, fibronectin, collagen I and collagen III was significantly increased in the NB group, while the expression of Smad6 was decreased (p < 0.01). HE and Masson staining in the NB group showed increased collagen levels and hypertrophy of smooth muscle cells. Children with NB had a low bladder volume ratio (BVR), low compliance (△C) and high maximum bladder pressure, low maximum flow rate, large postvoid residual volume, low bladder contraction index and low bladder voiding efficiency. The expression of α-SMA was negatively correlated with the BVR (r =  − 0.7066, P = 0.0223) and △C (r =  − 0.6516, P = 0.0412). We conclude that the TGF-β1/Smads/α-SMA pathway is activated in the bladder tissue of children with NB and may be involved in the processes causing histological and functional changes.

Muscarinic-3-receptor positive allosteric modulator ASP8302 in patients with underactive bladder. A randomized controlled trial

AIM

The aim of this study is to evaluate safety and efficacy of ASP8302, a novel positive allosteric modulator for the muscarinic M3 receptor (M3-PAM), in patients with underactive bladder (UAB).

METHODS

A randomized, double-blind, placebo-controlled multicenter study was performed in adult male/female subjects with UAB, defined as incomplete bladder emptying (postvoid residual volume [PVR] > 100 ml) without significant bladder outlet obstruction and/or overactive bladder. Subjects were randomized (1:1) to receive 4-week oral once-daily administration of 100 mg ASP8302 or matching placebo. Primary endpoint was a change from baseline in PVR measured by catheterization after standardized bladder filling (PVR_C2 ). Other endpoints included PVR and bladder voiding efficiency (BVE) measured in various ways, uroflowmetry, bladder diary, and questionnaires. Pressure-flow studies were performed in a subgroup.

RESULTS

One hundred and thirty-five patients were randomized (ASP8302 group: 65 patients, placebo group: 70 patients). The median change in PVR_C2 was -40.0 ml (ASP8302) versus -35.0 ml (placebo) and the difference between groups was -5.0 ml (p = 0.960). In males, functional and symptomatic outcomes improved, for example, maximum urine flow rate (Q_max ) and detrusor pressure at Q_max (P_det.Qmax ) increased (mean difference in change ASP8302 vs. placebo: 3.8 ml/s, p = 0.031 and 12.7 cm H₂ O, p = 0.034, respectively). Urinary incontinence episodes/24 h decreased in males with preexisting incontinence (mean difference: -0.35; p = 0.028). The incidence of adverse events was similar between study groups (ASP8302: 33.3%, placebo: 31.4%). In the included subjects, both baseline urine flow and bladder voiding pressure was low. Compared with PVR, simultaneous BVE measurements were more consistent between various methods (spontaneous vs. standardized bladder filling, catheterization vs. ultrasound [US]).

CONCLUSIONS

ASP8302 was safe and well tolerated in patients with UAB identified by nonurodynamic clinical criteria, but it did not show efficacy in the primary endpoint. However, in males it showed improvement of symptoms and functional parameters. BVE (using US) is a more optimal outcome measure than PVR in UAB.

Efficacy of TAC-302 for patients with detrusor underactivity and overactive bladder: a randomized, double-blind, placebo-controlled phase 2 study

PURPOSE

This multicenter, randomized, double-blind, placebo-controlled phase 2 study evaluated the efficacy and safety of TAC-302, a novel drug that restores neurite outgrowth, in patients with detrusor underactivity (DU) and overactive bladder (OAB).

METHODS

After 2-4 weeks of observation, patients were randomized 2:1 to receive oral TAC-302 200 mg or placebo twice daily for 12 weeks. The primary endpoint was detrusor contraction strength, estimated by bladder contractility index (BCI) for males and projected isovolumetric pressure 1 (PIP1) for females. Secondary endpoints included changes in bladder voiding efficiency (BVE) and safety.

RESULTS

Seventy-six patients were included (TAC-302, n = 52; placebo, n = 24). The mean (standard deviation [SD]) BCI for males was 64.6 (16.6) at baseline and 75.2 (21.1) at week 12 (p < 0.001) with TAC-302 (n = 27), and 61.3 (16.6) and 60.5 (16.7) (p = 0.82) with placebo (n = 11). The respective mean (SD) PIP1 for females was 18.8 (6.6) and 29.4 (9.4) (p < 0.001) with TAC-302 (n = 15), and 20.6 (7.5) and 25.5 (9.6) (p = 0.14) with placebo (n = 7). TAC-302 significantly increased BCI in males and BVE in both sexes. TAC-302 efficacy on OAB was not clearly shown. The incidences of adverse events (AEs), serious AEs, and AEs leading to dose interruption were similar between groups; no adverse drug reactions occurred.

CONCLUSION

Considering the significant effects on BCI in males and BVE in both sexes, TAC-302 may benefit patients with DU.

REGISTRATION

ClinicalTrials.gov Identifier NCT03175029 registered 6/5/2017.

Development of an artificial intelligence diagnostic system for lower urinary tract dysfunction in men

OBJECTIVES

To establish an artificial intelligence diagnostic system for lower urinary tract function in men with lower urinary tract symptoms using only uroflowmetry data and to evaluate its usefulness.

METHODS

Uroflowmetry data of 256 treatment-naive men with detrusor underactivity, bladder outlet obstruction, or detrusor underactivity + bladder outlet obstruction were used for artificial intelligence learning and validation using neural networks. An optimal artificial intelligence diagnostic model was established using 10-fold stratified cross-validation and data augmentation. Correlations of bladder contractility index and bladder outlet obstruction index values for the artificial intelligence system and pressure flow study values were examined using Spearman's correlation coefficients. Additionally, diagnostic accuracy was compared between the established artificial intelligence system and trained urologists with uroflowmetry data of 25 additional patients by χ² -tests. Detrusor underactivity was defined as bladder contractility index ≤100 and bladder outlet obstruction index ≤40, bladder outlet obstruction was defined as bladder contractility index >100 and bladder outlet obstruction index >40, and detrusor underactivity + bladder outlet obstruction was defined as bladder contractility index ≤100 and bladder outlet obstruction index >40.

RESULTS

The artificial intelligence system's estimated bladder contractility index and bladder outlet obstruction index values showed significant positive correlations with pressure flow study values (bladder contractility index: r = 0.60, P < 0.001; bladder outlet obstruction index: r = 0.46, P < 0.001). The artificial intelligence system's detrusor underactivity diagnosis had a sensitivity and specificity of 79.7% and 88.7%, respectively, and those for bladder outlet obstruction diagnosis were 76.8% and 84.7%, respectively. The artificial intelligence system's average diagnostic accuracy was 84%, which was significantly higher than that of urologists (56%).

CONCLUSIONS

Our artificial intelligence diagnostic system developed using the uroflowmetry waveform distinguished between detrusor underactivity and bladder outlet obstruction with high sensitivity and specificity in men with lower urinary tract symptoms.

Post-void residual urine ratio: A novel clinical approach to the post-void residual urine in the assessment of males with lower urinary tract symptoms

Purpose

To assess the correlation between post-void residual urine ratio (PVR-R) and pathological bladder emptying diagnosed by pressure-flow studies (PFS) in males with lower urinary tract symptoms (LUTS).

Materials and Methods

PVR-R and PVR urine were evaluated in 410 males underwent PFS for LUTS. PVR-R was the percentage of PVR to bladder volume (voided volume+PVR). Schafer and International Continence Society (ICS) nomograms, Bladder Contractility Index (BCI) were used to diagnose bladder outlet obstruction (BOO) and detrusor underactivity (DUA). We subdivided the cohort in 4 groups: Group I, BOO+/DUA+; Group II, BOO-/DUA+; Group III, BOO+/DUA−; Group IV, BOO−/DUA− (control group). We subdivided the 4 groups according to PVR-R strata: (1) 0%–20%; (2) 21%–40%; (3) 41%–60%; (4) 61%–80%; (5) 81%–100%.

Results

Group I had a greater median PVR-R (50%) with a >40% in 61.4% of the cohort. Median PVR-R was 16.6% in Group II, 24% in Group III, and 0% in the control Group. According to ICS nomograms and BCI, median PVR-R and PVR were significantly higher (p<0.001) in obstructed and underactive males. PVR-R threshold of 20% allowed to recognize males with voiding disorders with high sensibility, specificity, PPV, and NPV. A PVR-R cut-off of 40% identified males with associated BOO and DUA and more severe voiding dysfunction.

Conclusions

A higher PVR-R is related to a more severe pathological bladder emptying, and to the association of BOO and DUA. PVR-R may have a clinical role in first assessment of males with LUTS and severe voiding dysfunction.

Clinical diagnostic criteria for detrusor underactivity: A report from the Japanese Continence Society working group on underactive bladder

Detrusor underactivity (DU) is a common bladder dysfunction that causes lower urinary tract symptoms (LUTS) in both men and women. Currently DU can only be diagnosed by an invasive urodynamic test. Underactive bladder (UAB) is the symptom-based correlate of DU, as is the case with overactive bladder (OAB) and detrusor overactivity (DO). The International Continence Society (ICS) consensus group has recently proposed a working definition of UAB as a symptom syndrome suggestive of DU. However, a symptom complex of UAB is shared by LUTS attributable to bladder outlet obstruction (BOO). Thus, UAB is not specific for DU, leading to difficulties in determining a therapeutic target (DU or BOO) in the initial management of UAB. Under these circumstances, a consensus group was formed under the auspices of the Japanese Continence Society (JCS) and diagnostic criteria were produced to potentially identify patients likely to have DU, without a pressure/flow study-based diagnosis. Certain symptoms and several noninvasive test parameters have been reported as clinical predictors of DU, and were suggested to discriminate DU from BOO. Of these predictive factors, the more commonly used parameters were used to develop clinical diagnostic criteria for DU. This article presents the clinical diagnostic criteria for DU proposed by the JCS consensus group and aims to summarize the background discussion by the group.