Background

Bladder health is an understudied state and difficult to measure due to lack of valid and reliable instruments. While condition specific questionnaires assess presence, severity and degree of bother from lower urinary tract symptoms, the absence of symptoms is insufficient to assume bladder health. This study describes the methodology used to validate a novel bladder health instrument to measure the spectrum of bladder health from very healthy to very unhealthy in population based and clinical research.

Methods

Three samples of women are being recruited: a sample from a nationally representative general population and two locally recruited clinical center samples-women with a targeted range of symptom severity and type, and a postpartum group. The general population sample includes 694 women, 18 years or older, randomly selected from a US Postal delivery sequence file. Participants are randomly assigned to electronic or paper versions of the bladder health instrument along with a battery of criterion questionnaires and a demographic survey; followed by a retest or a two-day voiding symptom diary. A total of 354 women around 7 clinical centers are being recruited across a spectrum of self-reported symptoms and randomized to mode of completion. They complete the two-day voiding symptom diary as well as a one-day frequency volume diary prior to an in-person evaluation with a standardized cough stress test, non-invasive urine flowmetry, chemical urine analysis and post void residual measurement. Independent judge ratings of bladder health are obtained by interview with a qualified health care provider. A total of 154 postpartum women recruited around 6 of the centers are completing similar assessments within 6-12 weeks postpartum. Dimensional validity will be evaluated using factor analysis and principal components analysis with varimax rotation, and internal consistency with Cronbach's alpha. Criterion validity will be assessed using multitrait-multimethod matrix including correlations across multiple data sources and multiple types of measures.

Discussion

We aim to validate a bladder health instrument to measure the degree of bladder health within the general population and among women (including postpartum) recruited from local clinical centers. Trial registration NCT04016298 Posted July 11, 2019 ( https://www.clinicaltrials.gov/ct2/show/NCT04016298?cond=bladder+health&draw=2&rank=1 ).

OBJECTIVES: To describe the methods for the in-person assessment of the RISE FOR HEALTH (RISE) study, a population-based multicenter prospective cohort study designed to identify factors that promote bladder health and/or prevent lower urinary tract symptoms in adult women, conducted by the Prevention of Lower Urinary Tract Symptoms Research Consortium (PLUS). METHODS AND RESULTS: A subset of RISE participants who express interest in the in-person assessment will be screened to ensure eligibility (planned n = 525). Eligible consenting participants are asked to complete 15 physical assessments in addition to height and weight, to assess pelvic floor muscle function, musculoskeletal (MSK) status, and pain, and to provide urogenital microbiome samples. Pelvic floor muscle assessments include presence of prolapse, strength, levator attachment integrity (tear) and myofascial pain. MSK tests evaluate core stability, lumbar spine, pelvic girdle and hip pain and function. Participants are asked to complete the Short Physical Performance Battery to measure balance, lower extremity strength, and functional capacity. All participants are asked to provide a voided urine sample and a vaginal swab for microbiome analyses; a subset of 100 are asked to contribute additional samples for feasibility and validation of a home collection of urinary, vaginal, and fecal biospecimens. RESULTS: Online and in-person training sessions were used to certify research staff at each clinical center before the start of RISE in-person assessments. Standardized protocols and data collection methods are employed uniformly across sites. CONCLUSIONS: The RISE in-person assessment is an integral portion of the overall population-based RISE study and represents an innovative approach to assessing factors hypothesized to promote bladder health and/or prevent lower urinary tract symptoms. Data collected from this assessment will be used to prioritize future research questions and prevention strategies and interventions. This description of the assessment methods is intended to provide methodologic transparency and inform other researchers who join efforts to understand and improve bladder health.

INTRODUCTION: The prevalence of healthy bladder storage and emptying function in community-dwelling women is not well established. METHODS: A planned secondary analysis of a US cross-sectional study designed to validate a bladder health instrument was conducted in women aged ≥18 years. A subset was invited to complete the novel 2-day bladder health diary capturing bladder storage and emptying experiences. Overall healthy bladder function was defined as ≤8 waking/daytime voids and ≤1 void during sleeping/nighttime; along with the absence of leakage, urgency, emptying difficulties (initiation, flow, efficacy, relief of urge sensation) and pain. Descriptive statistics of healthy bladder functions and regression models of factors associated with healthy function are reported. RESULTS: Of the 383 invited, 237 (62%) eligible women returned complete dairies. Of these, 12% (29/237) met criteria for overall healthy bladder function. Most (96%) denied pain, 74% had healthy daytime and 83% had healthy nighttime voiding frequency, 64% were continent, 36% reported healthy emptying and 30% denied any urgency episodes. Middle income (odds ratio [OR]:95% confidence interval [CI] = 11.4:1.9-67.4 for $75k-$99 999 vs. $25 000-$49 999), Graduate education (4.8:1.4-17) and previously seeking treatment for bladder problems (OR:95%CI = 0.1; 0-0.9) were associated with overall healthy function. CONCLUSION: The prevalence of overall healthy bladder function was very low based on our strict definition of health as measured on a 2-day diary. However, most women had healthy voiding frequency and denied pain or urinary leakage. Postvoid dribbling and urgency most commonly contributed to an overall unhealthy bladder. Further investigation is needed to determine whether these diary derived measures are meaningful for patient-oriented bladder health research.

Aim

To report research terminology and definitions for describing healthy bladder function among women and girls.

Methods

The Prevention of Lower Urinary tract Symptoms (PLUS) Consortium developed research terminology and definitions for elements of healthy bladder function based on existing understanding of storage and emptying functions of the bladder and accepted definitions of lower urinary tract symptoms (LUTS). The novel concept of a bladder "bioregulatory" function was also proposed. Elements of bladder function corresponding to bladder health (BH) and LUTS were developed and refined using an iterative process. A comprehensive reference table structured by bladder function (Storage, Emptying, and Bioregulatory) and elements of each function was created to document proposed research terminology and definitions.

Results

The BH research definitions for each bladder function are: (1) Storage: the ability to hold urine for a reasonable duration of time and sense bladder fullness without fear of or concern about urgency, discomfort or leakage; (2) Emptying: the ability to empty the bladder completely in a timely, efficient, effortless, comfortable manner; and (3) Bioregulatory: the bladder barrier protects the individual/host from pathogens, chemicals, and malignancy. Research definitions for seven Storage, seven Emptying, and three Bioregulatory elements of function are presented. Novel LUTS research definitions were developed when gaps in existing definitions were identified or nonclinical language was desired.

Conclusions

PLUS BH definitions reflect a transdisciplinary approach to standardizing research definitions for elements of bladder function from a perspective of health rather than dysfunction and provide a framework for studying BH in clinical practice, public health promotion, and LUTS prevention.

BACKGROUND: Existing bladder-specific measures lack the ability to assess the full range of bladder health, from poor to optimal health. OBJECTIVE: This study aimed to report evidence of validity of the self-administered, multidimensional bladder health scales and function indices for research in adult women. STUDY DESIGN: A cross-sectional population-based validation study with random assignment to paper or electronic administration was conducted using national address-based probability sampling supplemented by purposive sampling of women with lower urinary tract symptoms in 7 clinical research centers. Construct validity of the bladder health scales and function indices was guided by a multitrait-multimethod approach using health and condition-specific questionnaires, bladder diaries, expert ratings of bladder health, and noninvasive bladder function testing. Internal dimensional validity was evaluated using factor analysis; internal reliability was assessed using paired t-tests and 2-way mixed-effects intraclass correlation coefficient models. Chi-square, Fisher exact, or t-tests were used for mode comparisons. Convergent validity was evaluated using Pearson correlations with the external construct measures, and known-group validity was established with comparison of women known and unknown to be symptomatic of urinary conditions. RESULTS: The sample included 1072 participants. Factor analysis identified 10 scales, with Cronbachs alpha ranging from 0.74 to 0.94. Intraclass correlation coefficients of scales ranged from 0.55 to 0.94. Convergent validity of the 10 scales and 6 indices ranged from 0.52 to 0.83. Known-group validity was confirmed for all scales and indices. Item distribution was similar by mode of administration. CONCLUSION: The paper and electronic forms of the bladder health scales and function indices are reliable and valid measures of bladder health for use in womens health research.

Lower urinary tract symptoms (LUTS) are highly prevalent in women, and are expected to impose a growing burden to individuals and society as the population ages. The predominance of research related to LUTS has focused on underlying pathology, disease mechanisms, or the efficacy of treatments for women with LUTS. Although this research has been vital for helping to reduce or ameliorate LUTS conditions, it has done little to prevent the onset of LUTS. Health promotion and prevention require an expansion of scientific inquiry beyond the traditional paradigm of studying disease mechanisms and treatment to the creation of an evidence base to support recommendations for bladder health promotion and, in turn, prevention of LUTS. The National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK) introduced the concept of prevention as an important priority for women's urologic research as a prelude to supporting the formation of the Prevention of Lower Urinary Tract Symptoms (PLUS) research consortium. In this article, we introduce the PLUS research consortium to the scientific community; share the innovative paradigms by which the consortium operates; and describe its unique research mission: to identify factors that promote bladder health across the life course and prevent the onset of LUTS in girls and women.

INTRODUCTION: The spectrum of bladder health and the factors that promote bladder health and prevent lower urinary tract symptoms (LUTS) among women are not well understood. This manuscript describes the rationale, aims, study design, sampling strategy, and data collection for the RISE FOR HEALTH (RISE) study, a novel study of bladder health in women conducted by the Prevention of Lower Urinary Tract Symptom (PLUS) Research Consortium. METHODS AND RESULTS: RISE is a population-based, multicenter, prospective longitudinal cohort study of community-dwelling, English- and Spanish-speaking adult women based in the United States. Its goal is to inform the distribution of bladder health and the individual factors (biologic, behavioral, and psychosocial) and multilevel factors (interpersonal, institutional, community, and societal) that promote bladder health and/or prevent LUTS in women across the life course. Key study development activities included the: (1) development of a conceptual framework and philosophy to guide subsequent activities, (2) creation of a study design and sampling strategy, prioritizing diversity, equity, and inclusion, and (3) selection and development of data collection components. Community members and cross-cultural experts shaped and ensured the appropriateness of all study procedures and materials. RISE participants will be selected by simple random sampling of individuals identified by a marketing database who reside in the 50 counties surrounding nine PLUS clinical research centers. Participants will complete self-administered surveys at baseline (mailed paper or electronic) to capture bladder health and LUTS, knowledge about bladder health, and factors hypothesized to promote bladder health and prevent LUTS. A subset of participants will complete an in-person assessment to augment data with objective measures including urogenital microbiome specimens. Initial longitudinal follow-up is planned at 1 year. DISCUSSION: Findings from RISE will begin to build the necessary evidence base to support much-needed, new bladder health promotion and LUTS prevention interventions in women.

Background

Lower urinary tract symptoms (LUTS) are common in children and adolescents. Non-invasive tests evaluating bladder function are generally preferred over invasive tests, yet few studies have explored the range of normative values for these tests in healthy, asymptomatic children.

Objective

To define normative reference ranges for non-invasive tests of bladder function in healthy, asymptomatic girls and adolescents.

Study design

A comprehensive search strategy was performed in seven electronic databases through October 2019. English-language studies reporting data on voiding frequency, voided and postvoid residual volumes (PVR) and uroflowmetry results in healthy, asymptomatic girls (mean age ≥ 5 years) were included. Two independent reviewers performed study review, data extraction, and quality assessment. Overall mean estimates and 95% confidence intervals for each bladder function parameter were calculated using random effects models, and 95% normative reference values were estimated.

Results

Ten studies met eligibility criteria for the meta-analysis (n = 2143 girls, age range: 3-18). Mean estimates of maximum voided volume and PVR were 233.4 ml (95% CI 204.3-262.6; n = 1 study) and 8.6 ml (95% CI 4.8-12.4; n = 2 studies) respectively. Pooled mean estimates for uroflowmetry parameters were: 21.5 ml/s (95% CI 20.5-2.5) for maximum flow rate (n = 6 studies), 12.5 ml/s (95% CI 11.2-13.8) for mean flow rate (n = 6 studies), 6.8 s (95% CI 4.4-9.3) for time to maximum flow (n = 3 studies), 15.7 s (95% CI 13.0-18.5) for flow time (n = 3 studies), and 198.7 ml (95% CI 154.2-234.2) for voided volume (n = 9 studies). No studies reported estimates of voiding frequency. Between-study heterogeneity was high (89.0-99.6%).

Conclusions

Although we were able to calculate pooled mean estimates for several parameters, the small number of included studies and the wide age ranges of participants preclude generalization of reference values to all healthy girls. Further research is needed to determine normative reference values within specific age groups.

Background: Little research to date has focused on lower urinary tract symptom (LUTS) prevention and bladder health promotion in women. To address this gap, the Prevention of LUTS Research Consortium developed the following working bladder health definition: "A complete state of physical, mental, and social well-being related to bladder function [that] permits daily activities [and] allows optimal well-being." To begin to inform and quantify this definition, we used data from the Boston Area Community Health Survey, drawing upon its rare collection of information on LUTS and LUTS-specific interference with activities. Methods: At baseline, participants reported their frequency of 15 LUTS and interference with 7 activities. Prevalence ratios (PRs) were calculated by generalized linear models with robust variance estimation, adjusting for LUTS risk factors and individual LUTS. Results: Of the 3169 eligible participants, 17.5% reported no LUTS or interference, whereas the remaining 82.5% reported some frequency of LUTS/interference: 15.1% rarely; 21.7% a few times; 22.6% fairly often/usually; and 22.9% almost always. LUTS independently associated with interference were urgency incontinence, any incontinence, urgency, nocturia, perceived frequency, and urinating again after <2 hours (PRs = 1.2-1.5, all p < 0.05). Conclusions: Our findings suggest that bladder health exists on a continuum, with approximately one in five women considered to have optimal bladder health (no LUTS/interference), the majority to have intermediate health (LUTS/interference rarely to usually), and a further one in five to have worse or poor health (LUTS/interference almost always). These findings underscore the need for LUTS prevention and bladder health promotion.