Uroflow measurements in healthy female volunteers

Reliability of Uroflowmetry Pattern Interpretation in Adult Women

INTRODUCTION

Uroflowmetry is often used to assess lower urinary tract symptoms (LUTS). Criteria for characterization of flow patterns are not well established, and subjective interpretation is the most common approach for flow curve classification. We assessed the reliability of uroflowmetry curve interpretation in adult women.

MATERIALS AND METHODS

Uroflowmetry studies were obtained in 296 women who participated in an observational cohort study. Four investigators with expertise in female LUTS and urodynamics reviewed and categorized each tracing for interrater reliability. A random subset of 50 tracings was re-reviewed by each investigator for intrarater reliability. The uroflowmetry tracings were rated using categories of continuous, continuous fluctuating, interrupted, and prolonged. Other parameters included flow rate, voided volume, time to maximum flow, and voiding time. Agreement between raters is summarized with kappa (k) statistics and percentage where at least three raters agreed.

RESULTS

The mean age of participants was 44.8 ± 18.3 years. Participant age categories were 18-24 years: 20%; 25-34 years: 17%; 35-64 years: 42%; 65+ years: 18%. Nine percent described their race as Asian, 31% Black, 62% White, and 89% were of non-Hispanic ethnicity. The interrater reliability was highest for the continuous flow category (k = 0.65), 0.47 for prolonged, 0.41 for continuous fluctuating, and 0.39 for interrupted flow curves. Agreement among at least three raters occurred in 74.3% of uroflow curves (69% for continuous, 33% for continuous fluctuating, 23% for interrupted, and 25% for prolonged). For intrarater reliability, the mean k was 0.72 with a range of 0.57-0.85.

CONCLUSIONS

Currently accepted uroflowmetry pattern categories have fair to moderate interrater reliability, which is lower for flow curves that do not meet "continuous" criteria. Given the subjective nature of interpreting uroflowmetry data, more consistent and clear parameters may enhance reliability for use in research and as a screening tool for LUTS and voiding dysfunction.

TRIAL REGISTRATION

Parent trial: Validation of Bladder Health Instrument for Evaluation in Women (VIEW); ClinicalTrials.gov ID: NCT04016298.

Reassessing Normal Voiding Standards: A Cross-Sectional Study Based on Medical Professionals' Evaluations with Portable Uroflowmetry and IPSS

Background/Objectives: LUTS and voiding dysfunctions are prevalent in urology clinics, with uroflowmetry and IPSS as the prevailing diagnostic methods. Nevertheless, objective assessment can be constrained by age, gender, and variability in the test conditions. Portable (home) uroflowmetry addresses these limitations, allowing for more natural urinary flow recordings beyond clinic confines. This study aims to characterize spontaneous voiding patterns in healthcare professionals, exploring gender differences, variability in repeated measurements, and correlations among voiding parameters, IPSS, age, and BMI. Methods: This cross-sectional study was conducted during the SIU 43rd Congress in Istanbul using smart uroflow devices such as the Oruba Oruflow Uroflow Recorder, which were installed in public toilets. A total of 431 healthcare professionals participated by providing demographic information and completing the IPSS questionnaire. The data analysis included uroflowmetric parameters such as maximum flow rate (Qmax), average flow rate (Qave), and voided volume (VV), in addition to IPSS and demographic data to assess the possible associations with IPSS, age, BMI, and gender differences. Results: Of the participants, 76% were male and 24% female, with a higher prevalence of LUTS in women. Despite no significant gender difference in voided volume, men with lower volumes demonstrated more severe LUTS. Notably, women exhibited higher Qmax and Qave rates irrespective of their IPSS scores, contrasting with men whose flow rates declined with age and LUTS severity. In men, the total IPSS score was inversely associated with uroflowmetric performance, particularly impacting voiding symptoms over storage symptoms. Repeated measurements revealed noteworthy variability in Qmax and VV, without any influence from gender, BMI, age, or symptom severity. Conclusions: Our findings highlight the importance of gender-specific considerations in evaluating voiding complaints through uroflowmetry and IPSS. The significant variability observed in repeated uroflowmetry studies underlines the need for multiple measurements. Overall, this research emphasizes the significance of portable (home) uroflowmetry and calls for a reassessment of normal voiding standards in (non) clinical settings.

Evaluation of Uroflowmetry Curve Patterns and Nomogram Construct in Healthy Nulliparous Female Adults

OBJECTIVE

The aims of the study were to construct uroflowmetry nomograms, evaluate uroflowmetry flow rate patterns, and graphically illustrate overlaid uroflowmetry curves in nulliparous female adult volunteers.

METHODS

We performed a prospective cross-sectional study evaluating uroflowmetry curve and flow rate patterns on a cohort of nulliparous female adult volunteers. Primary outcome was construction of uroflowmetry maximum and average flow rate nomograms. Secondary outcomes included evaluation of uroflowmetry flow rate patterns and graphical illustrations of overlaid uroflowmetry curves. Uroflowmetry printouts were overlaid and used to create a model of uroflow patterns, and nomogram curves were analyzed in 5 groups based on voided volumes.

RESULTS

We enrolled 164 participants and 158 had voided volumes between 50 mL and 800 mL. Participants' mean age and body mass index were 25 years and 23, respectively. Maximum and average flow rate nomograms were created, and analysis of uroflow parameters was performed. Median voided volume was 241 mL (149-431 mL), the median maximum flow was 29 mL/s (20-38 mL/s), and the median average flow was 15 mL/s (10-19 mL/s). Participants were divided into 5 groups based on voided volumes. The nomogram patterns for each voided volume group were visually different from typical nomogram patterns.

CONCLUSIONS

Uroflowmetry curves and flow rates vary significantly according to voided volume. Our study suggests that in normal healthy nulliparous female adults there is likely a broader range of normal flow rates and uroflowmetry curves than what has been previously reported. Further research is needed to investigate the accuracy of these finding.

Normative noninvasive bladder function measurements in healthy women: A systematic review and meta-analysis

AIM

To conduct an evidence synthesis of normative reference values for bladder function parameters in women.

METHODS

We conducted a systematic review and meta-analysis of studies reporting bladder function parameters obtained from noninvasive tests in healthy women. Seven databases were searched for relevant studies from inception through December 2018, with manual searching of reference lists. We included English language articles that provided quantitative data on urination frequency, voided and postvoid residual volumes, and uroflowmetry results in women without lower urinary tract symptoms. Study selection, data extraction, and quality assessment were undertaken by at least two independent reviewers. Random-effects meta-analytic models were used to derive study-level pooled mean estimates and 95% confidence intervals.

RESULTS

A total of 24 studies (N = 3090 women, age range, 18-91 years) met eligibility criteria. Pooled mean estimates of bladder function parameters were: 6.6 daytime voids (95% confidence interval (95% CI), 6.2, 7.0), 0.4 nighttime voids (95% CI, 0.0, 0.8), 1577 mL for 24-hour voided volume (95% CI 1428,1725); 12 mL for postvoid residual volume (95% CI, 4, 20); and 28 mL/sec for maximum flow rate (95% CI, 27,30). Between-study heterogeneity was high for all outcomes (I²  = 61.1-99.6%), but insufficient data were available to explore reasons for this high heterogeneity (eg, differences by age).

CONCLUSION

Although summary mean estimates of bladder function parameters were calculated, the wide heterogeneity across studies precludes generalization of these estimates to all healthy women. Further research is needed to determine normative reference values within specific groups, such as those defined by age.

Evaluation of intra-individual test-re-test variability of uroflowmetry in healthy women and women suffering from stress, urge, and mixed urinary incontinence

INTRODUCTION AND HYPOTHESIS

The objective was to evaluate the intra-individual variability of uroflowmetry (UFM) in healthy control subjects and women suffering from stress, urge, and mixed urinary incontinence.

METHODS

A total of 35 healthy controls (group A) and 105 women suffering from urinary incontinence were enrolled in the study. Thirty-five women suffered from stress urinary incontinence (group B), 35 women suffered from mixed urinary incontinence (group C), and 35 women with overactive bladder both dry and wet (group D). All participants were asked to perform UFM measurement three times. The following parameters were analyzed: voided volume (VV), peak flow (Q_max), average flow (Q_ave), volume-corrected peak flow cQ_max (cQ_max = Q_max/²√ VV), volume-corrected average flow (cQ_ave = Q_ave/²√ VV), and postvoid residual volume (PVR). Statistical analysis was performed using the analysis of variance on repeated measurements. Relative error was calculated using variation coefficients reported as a percentage of the average. All descriptive characteristics were reported as means ± standard deviation (SD). p values ≤0.05 were considered statistically significant.

RESULTS

No statistically significant intra-individual difference in any of the recorded parameters was identified among the three UFM recordings in groups A, C, and D. The intra-individual variability of the following parameters reached statistical significance in patients suffering from stress urinary incontinence (group B): Q_max (p = 0.0016), Q_ave (p = 0.0005), and cQ_ave (p = 0.0389). A significant difference was only observed in comparison between the first and second consecutive recordings.

CONCLUSIONS

This study provides evidence supporting the high yield and good intra-individual reproducibility of UFM.