Nocturnal polyuria: it's all about definition, and be Patient!

Psychometric properties and moderated mediation analysis of the ICIQ-NQOL in Chinese primary care patients with nocturia

BACKGROUND

Many individuals consider nocturia a significant nuisance, leading to a reduced health-related quality of life (HRQOL). However, there has been a lack of psychometrically sound patient-reported outcome measures to assess the impact of nocturia on patients in Chinese contexts. This study aimed to translate, culturally adapt, and validate the International Consultation on Incontinence Questionnaire Nocturia Quality of Life Module (ICIQ-NQOL) for use among primary care patients in Hong Kong, China. Additionally, it sought to investigate the mechanisms that link nocturia and sleep quality with HRQOL by employing moderated mediation analysis.

METHODS

The traditional Chinese version of the ICIQ-NQOL was developed through iterative translations, cognitive debriefing interviews, and panel reviews. The psychometric evaluation included assessments of factor structure, convergent validity, concurrent validity, known-group validity, internal consistency, test-retest reliability and responsiveness. Study instruments included the ICIQ-NQOL, International Prostate Symptom Score (IPSS), Pittsburgh Sleep Quality Index (PSQI), and a modified Incontinence Impact Questionnaire-Short Form (IIQ-7).

RESULTS

A total of 419 primary care patients were recruited from general outpatient clinics, among whom 228 experiencing an average of two or more nocturia episodes per night over the past four weeks. Confirmatory factor analysis supported the two-factor structure of the ICIQ-NQOL. Concurrent validity was confirmed by moderate correlations between the IIQ-7 total score and the total score as well as two domain scores of the ICIQ-NQOL (r ranging from 0.43 to 0.49, all p < 0.001). The ICIQ-NQOL also had moderate correlations with the IPSS total symptom score (r ranging from 0.40 to 0.48, all p < 0.001). Convergent validity was supported by moderate correlations between the global PSQI score and the total score as well as two domain scores of the ICIQ-NQOL (r ranging from 0.42 to 0.52, all p < 0.001). Known-group comparisons showed that the ICIQ-NQOL could differentiate between patients with and without nocturia in terms of sleep/energy domain score (p < 0.001), bother/concern domain score (p < 0.001), and total score (p < 0.001), each demonstrating a moderate Cohen's d effect size. Item-total correlations corrected for overlap exceeded 0.4, and Cronbach's alpha coefficients were greater than 0.7. Test-retest reliability was confirmed with intraclass correlation coefficients exceeding 0.7 among patients reporting no change in their nocturia symptoms at a 2-week follow-up. Regarding responsiveness, the Cohen's d effect sizes for differences in domain and total scores between the baseline and 2-week follow-up assessments were greater than 0.3 among patients showing improvement in nocturia. Our moderated mediation analysis indicated that sleep quality significantly moderated the impact of nocturia on HRQOL, with a notably stronger indirect effect among females compared to males.

CONCLUSIONS

The ICIQ-NQOL is a reliable and valid instrument for assessing the HRQOL in primary care patients suffering from nocturia. The findings advocate for gender-specific approaches in the management and treatment of nocturia to optimize HRQOL.

Nocturia: its characteristics, diagnostic algorithm and treatment

Nocturia is the complaint that an individual has to wake up at night one or more times to urinate. It is a frequent condition among older adults and entails detrimental effects with regard to sleeping, sexual activity, comfort, depression, mental function and vitality. It is clinically important to distinguish it from global polyuria, defined as a urinary rate ≥ 125 ml/h (3000 ml/day), as well as from nocturnal polyuria, which is an abnormally large volume of urine during sleep associated with a decreased daytime urine production. A Frequency Volume Chart (FVC), overnight water deprivation test with renal concentrating capacity test, and the nocturnal bladder capacity index are some of the methods that help establish the underlying pathology of this condition and hence define an adequate treatment plan.

Overlap between nocturnal polyuria, diurnal polyuria, and 24-h polyuria among men with nocturia

PURPOSE

A recent update in International Continence Society (ICS) terminology now recognizes nocturnal polyuria (NP) and diurnal polyuria (DP) as related subcategories of "Polyuria (global symptom)". This study determines the real-world clinical overlap between NP, DP, and 24-h polyuria (24hP) among men with nocturia.

METHODS

Analysis of frequency-volume charts from men ≥ 18 years with ≥ 1 nocturnal void(s). Three separate analyses were performed using different rate criteria for NP, DP, and 24hP: (1) urine production > 90 mL/h (extrapolated from a proposed definition for NP); (2) > 125 mL/h (extrapolated from a proposed definition for 24hP [3000 mL/24 h]); and (3) > 1.67 mL/kg/h (extrapolated from the current ICS definition for 24hP [> 40 mL/kg/24 h]). Subjects were categorized as having one of five mathematically permissible phenotypic combinations: (1) isolated NP, (2) isolated DP, (3) NP + 24hP, (4) DP + 24hP, and (5) NP + DP + 24hP.

RESULTS

167, 95, and 61 patients were included at criteria 1, 2, and 3, respectively, with 56%, 43%, and 30% of patients demonstrating overlapping phenotypes (i.e., phenotypic combinations 3-5) at cut-offs 1-3, respectively. The prevalence of NP was similar across cut-offs (81-87%), but the prevalence of NP without 24hP was highly threshold-dependent (43-73%).

CONCLUSION

Consistent with current ICS terminology, there exists a substantial overlap between NP, DP, and 24hP. As demonstrated in the current study, absolute volume-based criteria for NP/DP/24hP are indeed conducive to the diagnosis of concurrent NP + 24hP, and may be preferred over proportion-based NP criteria when both NP + 24hP are suspected.

Phenotyping nocturnal polyuria: circadian and age-related variations in diuresis rate, free water clearance and sodium clearance

BACKGROUND

this study compares diuresis rate, sodium clearance and free water clearance (FWC) by age and time of day (nighttime vs. daytime) in subjects with and without nocturnal polyuria (NP) to determine whether these variables affect the phenotype of NP.

METHODS

post hoc analysis of two prospective observational studies. Eight urine samples collected at 3-h intervals and a single blood sample were used to calculate daytime (10a/1p/4p/7p/10p) and nighttime (1a/4a/7a) diuresis rates, sodium clearance and FWC. Three mixed linear models were constructed for diuresis rate, sodium clearance and FWC using four predictor variables: NP status (present [nocturnal urine production >90 ml/h] vs. absent [≤90 ml/h]), time of day, age and study identification.

RESULTS

subjects with NP experienced higher nighttime versus daytime diuresis rates, sodium clearance and FWC. Regardless of NP status, increased age was accompanied by an increase in the ratio of nighttime/daytime diuresis rate, nighttime sodium clearance and daytime sodium clearance. FWC showed a complex age effect, which was independent of time of day or NP status.

CONCLUSIONS

age-related increases in nighttime/daytime diuresis rate, 24-h sodium clearance and 24-h FWC are not specific to subjects with NP. The age-related surge in either nocturnal sodium clearance or nocturnal FWC may represent the relevant substrate for behavioural or pharmacologic interventions targeting sodium diuresis or free water diuresis, respectively. Increases in FWC in older age groups may reflect impaired circadian rhythmicity of endogenous AVP or changes in responsiveness of the aged nephron to water clearance.

The mediating role of sleep quality in the association between nocturia and health-related quality of life

BACKGROUND

Even though the negative impacts of nocturia on sleep quality and health-related quality of life (HRQOL) have been documented in previous research, their interrelationship has been poorly studied. This study aimed to explore whether nocturia would affect sleep quality, which in turn affects HRQOL.

METHODS

Participants aged 40 and above were randomly recruited from a Hong Kong public primary care clinic. Participants were asked to report the average number of nocturia (waking up at night to void) pisodes per night over a 1-month period. The Pittsburgh Sleep Quality Index (PSQI) and the 12-Item Short Form Health Survey version 2 (SF-12 v2) were administered. The mediation analysis was tested using multistage regression approach and bootstrap method.

RESULTS

Of the 500 subjects who completed the survey, 31.2% reported symptomatic nocturia (having ≥2 nocturia episodes per night), and 60.4% experienced poor sleep quality (a PSQI global score > 5). Respondents with symptomatic nocturia had a poorer HRQOL in the domains of physical functioning (PF), role physical (RP) and social functioning (SF), general health (GH), vitality (VT) and physical component summary (PCS) of the SF-12 v2 than those without. Compared with the respondents without poor sleep quality, those with poor sleep quality had poorer HRQOL across all domains and summaries of the SF-12 v2. Mediation analysis found that sleep quality fully mediated the association between nocturia and the PF, RP and SF domains of the SF-12 v2, respectively, and partially mediated the association between nocturia and the GH, VT and PCS domains of the SF-12 v2, respectively.

CONCLUSIONS

We found that sleep quality mediated the association between nocturia and HRQOL. To enhance the HRQOL of patients with nocturia, clinicians should not only focus on nocturia symptoms, but also on their sleep quality.

Identifying men with global polyuria on a nocturnal-only voiding diary

AIMS

Nocturnal polyuria (NP) and global polyuria (GP) are not mutually exclusive. However, by rate, the common criteria for GP (40 mL/kg/24 hours [117 mL/kg/hour in a 70-kg individual] or 3000 mL/24 hours [125 mL/h]) are more stringent than those for NP (90 mL/hour during the sleep period or NP index [NPi; nocturnal volume/24-hour volume] > 0.33 [no minimum rate]). It remains unclear whether total nocturnal urine volume (NUV) may reliably delineate between NP patients with and without comorbid GP.

METHODS

A clinical database of men with lower urinary tract symptoms was searched for voiding diaries completed by patients reporting greater than or equal to 1 nocturnal void(s). Four separate analyses were performed using all combinations of the two NP and two GP criteria listed above. For each analysis, patients were included if they met the criteria for NP, and then stratified by presence or absence of GP (ie, NP + GP vs isolated NP).

RESULTS

Median NUV was greater among patients with NP + GP for all criteria combinations. Sensitivities greater than or equal to 80%/90%/100% for NP + GP were observed at 1275/1230/1085 mL for {NPi > 0.33 + 24-hour volume > 3000 mL}; 1075/1035/1035 mL for {NPi > 0.33 + 24-hour volume > 40 mL/kg}; 900/745/630 mL for {NUP > 90 mL/hour + 24-hour volume > 3000 mL}; and 1074/1035/990 mL for {NUP > 90 mL/hour + 24-hour volume > 40 mL/kg}.

CONCLUSIONS

An inordinate NUV among men with NP is fairly sensitive for comorbid GP. In the appropriate clinical setting, nocturnal-only diaries may suffice in the evaluation and follow-up of patients with NP, so long as outlying nocturnal volumes prompt a 24-hour diary/urine collection.

Diagnosing Nocturnal Polyuria from a Single Nocturnal Urine Sample

BACKGROUND

Patients with nocturnal polyuria (NP) experience a unique surge in nocturnal diuresis rate during the early hours of sleep.

OBJECTIVE

To determine the diagnostic utility of the volume and osmolality of a single early nocturnal urine sample in detecting NP.

DESIGN, SETTING, AND PARTICIPANTS

Analysis of 1 am urine samples obtained from two prospective observational studies at Ghent University Hospital involving participants recruited from a urology ambulatory care unit and those who consulted a continence clinic. Nocturic participants (one or more nocturnal void[s]; n=176) were stratified based on the presence (n=87) or absence (n=89) of NP (>90ml/h).

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

Receiver operating characteristic curves with Youden's Index were used to determine cutoff values for urine volume and urine osmolality (Uosm).

RESULTS AND LIMITATIONS

Individuals with NP demonstrated higher 1 am volume (400 [interquartile range 300-515] vs 210 [160-300] ml, area under the curve [AUC]=0.843, p< 0.001, cutoff = 350 ml) and lower Uosm (274 [201-348] vs 430 [320-664] mOsm/kg H₂O, AUC=0.774, p<0.001, cutoff=314 mOsm/kg H₂O) than those without NP. In combining cutoffs, the criteria of either 1 am volume ≥350ml or Uosm ≤314 mOsm/kg H₂O were 85% sensitive and 75% specific for NP, while criteria of both 1 am volume ≥350ml and Uosm ≤314 mOsm/kg H₂O were 60% sensitive and 92% specific for NP. Comparable AUC values, sensitivities, and specificities were observed in both men and women. Limitations include post hoc design and a relatively small study sample.

CONCLUSIONS

Individuals with NP are more likely than those without NP to produce a higher volume of more dilute urine (ie, "aquaresis") in the early hours of sleep. Analysis of easily measurable parameters of the first nocturnal void (for which 1 am values serve as a surrogate) in men and women with nocturia can predict a diagnosis of NP with a reasonably high degree of sensitivity and specificity.

PATIENT SUMMARY

Urologists often try to understand the specific reason why people wake up to urinate at night by asking them to record the amount of urine they make every time they go to the bathroom (also known as a "voiding diary") during the nighttime as well as the daytime-typically for a total of 1-3 days. In this study, we showed that an analysis of the composition of the urine that people produce when they first wake up to urinate at night might be sufficient to determine whether their symptoms are caused by excessive urine production or something else, and some people might find this urine study easier than keeping a voiding diary.

Development of a multivariate prediction model for nocturia, based on urinary tract etiologies

PURPOSE

The main objective of our study was to determine which combination of modifiable and non-modifiable parameters that could discriminate patients with nocturia from those without nocturia. This was a post-hoc analysis of 3 prospective, observational studies conducted in Ghent University. Participants completed frequency volume chart (FVC) to compare characteristics between patients with and without nocturia.

METHOD

This was a post hoc analysis of three prospective, observational studies conducted in Ghent University. Participants completed frequency volume chart (FVC) to compare characteristics between adults with and without nocturia. Study 1: adults with and without nocturia (n = 148); Study 2: patients ≥65 years with and without nocturnal LUTS (n = 54); Study 3: menopausal women before and after hormone replacement therapy (n = 43). All eligible patients (n = 183) completed a FVC during 24 hours (n = 13), 48 hours (n = 30) or 72 hours (n = 140). The combination of algorithms and number of determinants obtaining the best average area under the receiver operating curve (AUC-ROC) led to the final model. Differences between groups were assessed using the AUC-ROC and Mann- Whitney-Wilcoxon tests. Holm corrections were applied for multiple statistical testing. Also, the stability of the feature selection was evaluated.

RESULTS

The best discrimination was obtained when 13 determinants were included. However, a logistic regression model based on seven determinants selected with random forest had comparable discrimination including an optimal signature stability. It was able to discriminate almost perfectly between nights with and without nocturia.

CONCLUSION

Relevant information to accomplish the excellent predictability of the model is; functional bladder capacity, 24 hours urine output, nocturnal output, age, BMI. The multivariate model used in this analysis provides new insights into combination therapy as it allows simulating the effect of different available treatment modalities and its combinations.

Diagnostic and therapeutic recommendations for patients with nocturia

Introduction

Nocturia is defined as the urge to urinate at night when the micturition was directly preceded and followed by sleep. Due to its negative impact on the quality of life of patients, an effective treatment for this disease has become a significant therapeutic challenge. The aim of this article was to explain the main risk factors for the occurrence of nocturia and to present diagnostic and therapeutic schemes in the case of nocturnal polyuria (idiopathic night time polyuria).

Material and methods

A review of the literature was carried out and the available guidelines of international science societies, which provided the basis for the above recommendations, were analyzed.

Results

Detailed medical history should include information concerning: lower urinary tract symptoms (including nocturia), underlying illnesses, urogenital disorders, previous surgeries and medications administered. Keeping a bladder diary is recommended. The physical examination, depending on the patient's gender, should include gynecological examination with pelvic organ prolapse assessment or prostate evaluation. In laboratory tests, a urinalysis may be used, in particular cases a cytological analysis of urine sediment may be carried out. In addition, a possible ultrasound and/or cystoscopy may be conducted. Nocturia therapy should begin with modifying dietary habits, including compliance with the fluid regimen, avoiding alcohol, coffee and tea. Moderate physical exercise is also recommended. The pharmacological treatment of nocturia caused by nocturnal polyuria is based on the use of desmopressin at a daily single dose of 25 µg for women and 50 µg for men. The use of desmopressin allows for the reduction in the number of nocturia episodes, as well as improves the overall quality of life and sleep. Treatment with desmopressin can also be considered as a form of therapy added in people with an overactive bladder or benign prostatic hyperplasia, in which nocturia is a significant clinical problem.

Conclusions

Desmopressin is an effective and safe first-line treatment option in pharmacological therapy of nocturia caused by nocturnal polyuria.

Pretransplant defunctionalized bladder-overrated condition?

AIMS

The objective of this study was to evaluate the expression of bladder receptors in patients with defunctionalized bladder (DB) and to assess voiding behavior after refunctionalization.

METHODS

A total of 68 pretransplant patients were divided in two groups: DB (diuresis <300 mL/24 h; n = 33) and NDB (non-DB; diuresis ≥300 mL/24 h; n = 35). A sample of mucosa and detrusor at the site of the future ureteral implantation was collected. The following receptors were assessed by real-time polymerase chain reaction (qRT-PCR): M₂ , M₃ , α_1D , β₃ , P2X₂ , P2X₃ , TRPV1, TRPV4, TRPA1, and TRPM8. At 3, 6, and 12 months after transplant patients answered IPSS and ICIQ-OAB questionnaires and filled a 3-day 24 h frequency/volume chart (FVC) at 6 and 12 months.

RESULTS

The expression of all receptors in the mucosa and in the detrusor was similar in both groups, except from α_1D , which was overexpressed in the detrusor of DB relatively to NDB group. ICIQ-OAB symptom score was similar between the groups at 3, 6, and 12 months. There was a reduction of this score in both groups with time. The same pattern was found for IPSS score. Bother scores were similar between groups. No difference was observed for all FVC parameters between DB and NDB patients.

CONCLUSION

Gene expression of bladder receptors involved in micturition control was similar in patients with or without DB. Bladder behavior had a similar pattern independently of pretransplant residual diuresis. These findings question the relevance of the term DB in pretransplant patients.

Basic or extended urine sampling to analyse urine production?

BACKGROUND

Frequency volume charts are valuable tools to objectify urine production in patients with nocturia, enuresis or nocturnal incontinence. Analyses of daytime and nighttime urine (=basic collection) or analyses of urine samples collected every 3 h (=extended collection) extend this evaluation by describing circadian patterns of water and solute diuresis (=renal function profiles).

AIM

To assess intra-individual correlation and agreement between renal function profiles provided using basic and extended urine collections, and using two extended urine collections. To create a short-form of the extended collection.

METHODS

This prospective observational study was executed at Ghent University Hospital, Belgium. Study participation was open for anyone visiting the hospital. Participants collected one basic and two extended 24-h urine collections. Urinary levels of osmolality, sodium and creatinine were determined.

RESULTS

There was a moderate to strong correlation between results of basic and extended urinalyses. Comparing both extended urinalyses showed a moderate correlation between the eight individual samples and a weak to strong correlation between the mean daytime and nighttime values of renal functions. Different samples could be considered as most representative for mean daytime values, while all samples collected between 03 and 05am showed the highest agreement with mean nighttime values of renal function.

CONCLUSION

Since there is a good correlation and agreement between basic and extended urine collections to study the mechanisms underlying urine production, the choice of urine sampling method to evaluate urine production depends on the purpose. A nighttime-only urine sample collected between 03 and 05am may be the most practical approach.

The Prevalence of Nocturia and Nocturnal Polyuria: Can New Cutoff Values Be Suggested According to Age and Sex?

PURPOSE

The aims of this study were to assess the prevalence of nocturia and nocturnal polyuria (NP) and to define new cutoff values according to age and sex for both conditions.

METHODS

Data from a population-based prevalence survey conducted among a random sample of 2,128 adults were analyzed in this study. Participants were requested to fill out a questionnaire including the International Continence Society (ICS) definitions of lower urinary tract symptoms and the International Consultation on Incontinence Questionnaire - Short Form. Additionally, a 1-day bladder diary was given to each individual. The participants were divided into 5 age groups. The prevalence of nocturia was calculated based on definitions of nocturia as ≥1 voiding episodes, ≥2 episodes, and ≥3 episodes. NP was evaluated according to the ICS definition. The mean±standard errors and 95th percentile values were calculated in each group as new cutoff values for NP.

RESULTS

The prevalence of nocturia was estimated as 28.4%, 17.6%, and 8.9% for ≥1, ≥2, and ≥3 voiding episodes each night, respectively. When nocturia was defined as 2 or more voiding episodes at night, the prevalence decreased significantly. The mean NP index was 29.4%±15.0% in men and 23.1%±11.8% in women. For the age groups of <50 years, 50-59 years, and ≥60 years, the new cutoff values for the diagnosis of NP were calculated as 48%, 69%, and 59% for men and 41%, 50%, and 42% for women, respectively.

CONCLUSIONS

We found that the definition of nocturia was still controversial and that waking up once for voiding might be within the normal spectrum of behavior. The definition of NP should be modified, and new cutoff values should be defined using the data presented in our study and in other forthcoming studies.

Nocturia: The circadian voiding disorder

Nocturia is a prevalent condition of waking to void during the night. The concept of nocturia has evolved from being a symptomatic aspect of disease associated with the prostate or bladder to a form of lower urinary tract disorder. However, recent advances in circadian biology and sleep science suggest that it might be important to consider nocturia as a form of circadian dysfunction. In the current review, nocturia is reexamined with an introduction to sleep disorders and recent findings in circadian biology in an attempt to highlight the importance of rediscovering nocturia as a problem of chronobiology.

Can botox improve night-time overactive bladder symptoms in women?

AIMS

Despite the efficacy of intravesical onabotulinumtoxinA (Botox) therapy for urgency, urgency incontinence, and daytime frequency, its value in treatment of nocturia remains unclear. The aim of the prospective observational study was to assess the effect of onabotulinumtoxinA on night-time symptoms in women with overactive bladder (OAB), including nocturia, night-time urgency incontinence, and nocturnal voided volume as end-points.

METHODS

Women with idiopathic OAB (with at least one episode of urgency urinary incontinence (UUI) per day, ≥8 micturitions per 24 hr, and ≥2 nocturia episodes per night) were enrolled. Patients with nocturnal polyuria were excluded. Botox (100 U) was administered in 20 intra-detrusor injections. Post-void residual volumes (PVR) were checked at 2, 4, and 12 weeks. Participants completed a 3-day bladder diary and the King's Health Questionnaire (KHQ) before and 12 weeks after treatment, and reported the efficacy of the treatment on visual analog scale (VAS) at the final follow-up visit.

RESULTS

Seventy-six women completed the study. Botox injections were effective in the reduction of nocturia episodes (mean -0.98; P < 0.001) and night-time UUI episodes (-0.37; P < 0.001) compared to the baseline. The increase of mean voided volume of the night-time micturitions was 92.6 ml (P < 0.001). Patients reported a mean 58 points of improvement on the VAS. Urinary retention, which required self-catheterization, was observed in three patients.

CONCLUSIONS

Intravesical Botox injection provides significant benefit for night-time symptoms in OAB patients. Our results are applicable for women without nocturnal polyuria, and should prove useful when counseling patients about the risks and benefits of Botox. Neurourol. Urodynam. 36:648-652, 2017. © 2016 Wiley Periodicals, Inc.

Terminology, epidemiology, etiology, and pathophysiology of nocturia

Nocturia, awaking from sleep to void, has a negative impact on health and well-being. Nocturia affects men and women and is more prevalent among the elderly. More than two nocturnal voids is considered to be a clinically meaningful threshold associated with significant negative outcomes for health and well-being, and the timing of awakening has a significant bearing on the negative consequences of nocturia. Several serious underlying pathophysiologic conditions may be associated with nocturia. A thorough history and assessment of number and times of voids, void volume, and fluid intake is essential for determining the etiology of a patient's nocturia. With data obtained from the frequency-volume chart (FVC), which is used to collect quantitative voiding data, a patient's nocturia may be classified as global polyuria, nocturnal polyuria, reduced bladder capacity, or a combination of these categories. Global polyuria is defined as 24-hr urinary output that exceeds 40 ml/kg body weight and results in increased 24-hr urinary frequency. Nocturnal polyuria is defined as more than 20% of daily urine output at night in young patients and more than 33% in elderly patients. Reduced bladder capacity may be a result of idiopathic or neurogenic detrusor overactivity, bladder outlet obstruction, or reduced nocturnal bladder capacity. The pathophysiology underlying the findings of the FVC falls into five main categories: global polyuria, nocturnal polyuria, reduced bladder capacity, sleep disorders, and circadian clock disorders. This review discusses the epidemiology, etiology, and pathophysiology of nocturia.