Prevalence, Incidence, and Resolution of Nocturnal Polyuria in a Longitudinal Community-based Study in Older Men: The Krimpen Study

Nocturia and obstructive sleep apnoea

Nocturia, the need to urinate at night, is a common symptom in patients with obstructive sleep apnoea (OSA). Continuous positive airway pressure treatment can reduce nocturia in some patients, but the underlying mechanisms are complex and not fully understood. OSA affects the autonomic nervous system, oxidative stress and endothelial damage. Furthermore, the commonly held theory attributing polyuria to a false signal of cardiac overload and response natriuresis has limitations. A comprehensive approach to the management of nocturia in OSA, considering factors such as comorbidities, medication use, alcohol consumption and lifestyle, is needed. Effective management of nocturia in OSA requires a multidisciplinary approach, and urologists should be aware of the potential effect of OSA on physiology and refer patients for further testing at a sleep centre. In addition to continuous positive airway pressure, other interventions such as oral appliances and surgical obstruction treatment could be beneficial for some patients. Overall, understanding the complex interplay between OSA and nocturia is crucial for optimizing patient outcomes.

Nocturnal polyuria in women: results from the EpiNP study

INTRODUCTION AND HYPOTHESIS

Data from a large US population-based, cross-sectional, epidemiological study (the EpiNP Study) were used to assess the symptoms and bother experienced by women with nocturnal polyuria (NP).

METHODS

Consenting participants recruited from an online panel completed the baseline EpiNP survey online (Lower Urinary Tract Symptoms Tool and urological comorbidities). All reporting ≥2 voids/night and a random sample of 100 respondents, each reporting 0 or 1 void/night were asked to complete a 3-day web-based bladder diary recording time, volume, and urgency rating of each void. NP was calculated by the proportion of urine production that occurred during nocturnal hours using a Nocturnal Polyuria Index (NPI33) threshold of >0.33 or nocturnal urine production of >90 ml/h (NUP90). The frequency of participants reporting LUTS and bother was determined by age and NP: idiopathic NP, NP associated with overactive bladder (NPOAB), NP associated with comorbidities (NPCom), and no NP (did not meet NP criteria).

RESULTS

A total of 5,290 women completed the baseline survey. Mean age (range) was 54.9 (30-95) years; 1,841 (34.8%) reported ≥2 nocturnal voids. The prevalence of LUTS increased across the lifespan; however, bother associated with each LUTS decreased with increasing age. The percentage of women rating bother by nocturia episodes ≥2 "> somewhat" ranged from 40.3% to 68.3%, with bother ratings highest in the NPOAB and No NP groups.

CONCLUSIONS

NP is prevalent in women with considerable bother and is often associated with other urinary symptoms. Multifactorial causes and potential treatments of NP should be considered, particularly at a later age.

Laying the foundation for enhancing safety of desmopressin in older people: Validation of capillary blood sodium levels

PURPOSE

We aim to make desmopressin a safe treatment option for (older) patients at risk for hyponatremia, by introducing a new way of sodium monitoring. The goal is to reduce the risk of hyponatremia, enhance patient safety and ultimately introduce self-monitoring of sodium levels. The first step in the aforementioned is to validate capillary sodium.

MATERIALS AND METHODS

100 randomly selected patients admitted to the urology department received a single finger prick to collect capillary blood (250 µl) in a lithium-heparin tube. Each patient acted as its own control for the capillary and venous blood sample. Venous and capillary plasma sodium were analyzed by indirect ion-selective electrode measurement. The primary outcome was the agreement between capillary and venous sodium measurements, measured by the intra-class correlation coefficient (ICC).

RESULTS

One hundred paired blood samples were obtained of which four were excluded. There was no significant statistical difference observed between venous and capillary sodium (-0.23 mmol/L, p = 0.374). The ICC for single measures between capillary and venous sodium was 0.82 (95% confidence interval 0.75-0.88). Inter-method differences analyzed by a Bland-Altman plot and a Passing-Bablock regression did not reveal a statistically significant difference between both groups.

CONCLUSIONS

We demonstrated that venous and capillary sodium levels are interchangeable, taken into account the inter- and intravariability between analyses. We provided the first step towards a simple and safe solution for frequent sodium monitoring through a minimal invasive capillary blood collection. The results are of direct clinical relevance to safely use desmopressin in (older) patients at risk.

Urodynamic findings in female patients with nocturia: An age-matched case-control study

INTRODUCTION

Nocturia negatively impacts the quality of life and is associated with poor general health, but our understanding of its etiologies is incomplete. Urodynamic studies (UDS) findings in patients with nocturia are not well described and may help guide management. Our objective was to compare UDS findings with age-matched patients with and without nocturia.

MATERIALS AND METHODS

We retrospectively reviewed UDS findings of 1124 patients (2010-2017). A total of 484 (43%) presented with nocturia and 821 (73%) were female. Female patients were separated into age-matched groups with and without nocturia. Urinary symptoms, past medical diagnoses, demographic information, and UDS findings were compared.

RESULTS

A total of 596 female patients were included, 298 (50%) with nocturia and 298 without. Past medical history, including diabetes mellitus and cardiovascular disease, did not differ between groups. Patients with nocturia were more likely to have pelvic pain (p = 0.0014) and other daytime symptoms (frequency, urgency, and urgency incontinence). On UDS, patients with nocturia were more likely to have bladder outlet obstruction (BOO) (p = 0.025) and dysfunctional voiding (DV) (p < 0.0001). There was no difference in the frequency of detrusor overactivity (DO). Bladder capacity and postvoid residual volumes were lower, though not significantly, in the nocturia group.

CONCLUSIONS

When comparing UDS findings in contemporary, age-matched groups of female patients with and without nocturia, we found only BOO and DV to be associated with nocturia. While the treatment of nocturia is often aimed at managing DO, our data suggest that this may not be the primary urodynamic correlation with nocturia. Further studies are needed to assess whether successful treatment of BOO and DV can improve nocturia.

Nocturia due to nocturnal polyuria (NP). A common disorder

To the Editor, Nocturia is a significantly underestimated medical problem that affects seriously patients' quality of life, work engagement, productivity, and overall life conditions per se. Nocturia is a common condition, proven to be the most bothersome for patients with Lower Urinary Tract Symptoms (LUTS). People with two or more events of micturition per night have a significant increase in mortality rate and an increased risk of fall-related fractures if they visit the toilet two or more times per night [...].

The Prevalence of Nocturnal Polyuria in the United States: Results from the Epidemiology of Nocturnal Polyuria Study

BACKGROUND

The prevalence of nocturnal polyuria (NP), which is passing large volumes of urine during the main sleep period, has been investigated primarily in middle-aged to older men. There is thus a gap in the NP evidence base for women and for younger individuals.

OBJECTIVE

To estimate the prevalence of nocturia due to NP in the USA.

DESIGN, SETTING, AND PARTICIPANTS

This large epidemiologic study used a US population-representative sample of men and women aged ≥30 yr to assess the prevalence of NP (NCT04125186).

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

Consenting participants completed an online survey (Lower Urinary Tract Symptoms Tool and comorbidities). All who reported two or more voids per night and 100 random respondents each reporting no or one void per night were asked to complete a 3-d bladder diary. Two NP definitions were used: nocturnal urine production >90 ml/h (NUP90) and Nocturnal Polyuria Index >0.33 (NPI33). Crude and population-adjusted prevalence results were calculated from completed diaries for the following subgroups by sex and age: idiopathic NP; NP with overactive bladder (NP-OAB) or bladder outlet obstruction (NP-BOO; men only); NP associated with other comorbidities; and no NP (did not meet the NPI33 or NUP90 definition).

RESULTS AND LIMITATIONS

Among the 10,190 respondents who completed the survey, the mean age was 54.4 yr (range 30-95); 3,339 reported two or more nocturnal voids and 1,763 completed the 3-d diary (response rate 49.3%). The adjusted overall NP prevalence was 31.5% among men and 38.5% among women using the NPI33 definition, and 23.8% among men and 18.1% among women using NUP90. The adjusted idiopathic NP prevalence was lower among men (NPI33: 5.2%; NUP90: 1.4%) than among women (NPI33: 9.8%; NUP90: 4.0%). The prevalence of idiopathic NP decreased with age as NP associated with other possible causes increased with age in men (most common, BOO) and women (most common, OAB).

CONCLUSIONS

This is the first population-based study of NP prevalence to include men, women, and young adults. NP is common; a multifactorial etiology should be considered, particularly as age increases.

PATIENT SUMMARY

In this population-based US study, we examined the frequency of nighttime urination among men and women aged ≥30 y and older. We found that nighttime urination is common among men and women. Many conditions can lead to increased nighttime urination as people age.

Dietary salt with nitric oxide deficiency induces nocturnal polyuria in mice via hyperactivation of intrarenal angiotensin II-SPAK-NCC pathway

Nocturnal polyuria is the most frequent cause of nocturia, a common disease associated with a compromised quality of life and increased mortality. Its pathogenesis is complex, and the detailed underlying mechanism remains unknown. Herein, we report that concomitant intake of a high-salt diet and reduced nitric oxide (NO) production achieved through N^ω-Nitro-L-arginine methyl ester hydrochloride (L-NAME) administration in mice resulted in nocturnal polyuria recapitulating the clinical features in humans. High salt intake under reduced NO production overactivated the angiotensin II-SPAK (STE20/SPS1-related proline–alanine-rich protein kinase)-NCC (sodium chloride co-transporter) pathway in the kidney, resulting in the insufficient excretion of sodium during the day and its excessive excretion at night. Excessive Na excretion at night in turn leads to nocturnal polyuria due to osmotic diuresis. Our study identified a central role for the intrarenal angiotensin II-SPAK-NCC pathway in the pathophysiology of nocturnal polyuria, highlighting its potential as a promising therapeutic target.

This study reports a mouse model of nocturnal polyuria - increased urine production at night that causes compromised quality of life and may impact mortality in older people. The authors identify a molecular pathway in the kidney that could prove to be a promising drug target for nocturnal polyuria.

The Importance of Terminology for Quantifying Nocturia in Practice

BACKGROUND

Although nocturia, affecting mainly the elderly population, is a urinary tract symptom, it may also be a part of conditions not related to the urinary tract. In this scenario, nocturia terminology is crucial to avoid confusion and misunderstanding across different specialities. The International Continence Society (ICS) provides the updated nocturia terminology.

OBJECTIVE

To review, describe, and explain the applicability of nocturia terminology based on the ICS standardisation documents.

DESIGN, SETTING, AND PARTICIPANTS

The ICS report provides definitions on the terminology for nocturia and nocturnal lower urinary tract function, which were identified and summarised.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

Terminology was classified as symptoms and signs, and an explanation of how terms are applied in a bladder diary for use in clinical practice was given.

RESULTS AND LIMITATIONS

Terminology was classified into symptoms and signs. Nocturia is a symptom where the patient reports waking up to pass urine during their main sleep period, and every episode is followed by sleep or the intention to sleep. Nocturnal polyuria is a symptom when the patient perceives that they have passed large volumes of urine during the main sleep period. Enuresis is the complaint of incontinence that occurs while a patient is asleep and is usually unaware of it. All these terms can be a sign when quantified on the bladder diary. The remaining terminology is identified and quantified on the 3-d bladder diary (24-h voided volume, 24-h polyuria, nocturnal urine volume, night-time frequency, first morning void, night-time main sleep period).

CONCLUSIONS

The health care provider must understand the critical differences between the different terms. It will facilitate communication among all the professionals involved in the care of these patients. A 3-d bladder diary is a fundamental tool for assessing nocturia.

PATIENT SUMMARY

This paper has the objective of defining and explaining all the terms currently used for nocturia. For this purpose, we utilised the published standard terminology and summarised it with examples for better understanding and applicability.

Nocturnal polyuria in men performing uroflowmetry for lower urinary tract symptoms

PURPOSE

To assess the prevalence of nocturnal polyuria (NP) in males performing uroflowmetry (UF) for lower urinary tract symptoms (LUTS), the impact of NP on UF outcomes, and bladder emptying, the association between NP and LUTS.

MATERIALS AND METHODS

Men scheduled for UF were recruited in two Centres. Data collected were medical history, IPSS, UF, post-void residual urine volume (PVR), 3-day frequency-volume charts (FVC). The NP index was used to assess NP with a threshold of ≥ 33%. The relationship between NP and patient's aging was assessed.

RESULTS

162 patients were included in the analysis. Mean age was 70.95 ± 8.04 years. The prevalence of NP was 54.9% (89/162). 110 (68%) patients reported nocturia, and among these, NP was documented in 76 (69%). Nocturia was found in 85% (76/89) of the population with NP. Total IPSS score, IPSS items #1, #2 and #7 showed a significant difference in men with NP compared with those without. Maximum flow rate and PVR did not significantly change comparing men with or without NP. Mean voiding volume (VV) of the night-time micturitions was significantly higher in men with NP compared to those without NP (532.1 ± 275.6 ml vs 175 ± 168.7 ml respectively, p < 0001), while mean VV day-time micturitions and mean VV at UF did not change between groups.

CONCLUSIONS

NP had a high prevalence in men with LUTS performing UF. Aged males were more commonly affected by NP. Data demonstrated a strong relationship between NP and nocturia and increased urinary frequency while voiding symptoms were poorly related to NP.

Tradução para a língua portuguesa do artigo original em inglês “ The International Continence Society (ICS) report on the terminology for adult male lower urinary tract and pelvic floor symptoms and dysfunction”

Introdução

No desenvolvimento da terminologia do trato urinário inferior, devido à sua crescente complexidade, a terminologia para os sintomas e a disfunção do trato urinário inferior masculino e assoalho pélvico precisa ser atualizada, utilizando abordagem específica masculina e por meio de um relatório de consenso clinicamente embasado.

Métodos

Este relatório combina a contribuição de membros do Standardisation Committee da International Continence Society em um Grupo de Trabalho com especialistas reconhecidos no campo, assistido por muitos julgadores externos. Categorias clínicas centrais apropriadas e uma subclassificação foram desenvolvidas para fornecer uma codificação numérica para cada definição. Um extenso processo de 22 rodadas de revisão interna e externa foi desenvolvido para examinar exaustivamente cada definição, com tomada de decisão por opinião coletiva (consenso).

Resultados

Um relatório de terminologia para os sintomas e a disfunção do trato urinário inferior e do assoalho pélvico foi desenvolvido, abrangendo cerca de 390 definições/descritores separados. É clinicamente embasado nos diagnósticos mais comuns definidos. A clareza e a facilidade de uso foram os principais objetivos para torná-lo interpretável por profissionais e estagiários em todos os diferentes grupos de especialidades envolvidos na disfunção do trato urinário inferior e do assoalho pélvico masculino. Imagens específicas para homens (ultrassonografia, radiologia, tomografia computadorizada e ressonância magnética) foram um adicional importante, enquanto figuras apropriadas foram incluídas para complementar e ajudar a esclarecer o texto.

Conclusões

Um relatório de terminologia com base em consenso para sintomas e disfunção do trato urinário inferior e do assoalho pélvico masculino foi produzido visando ser um auxílio significativo para a prática clínica e um estímulo para a pesquisa.

Nocturnal Urine Production in Women With Global Polyuria

PURPOSE

Low nocturnal urine production (NUP) may be sufficient to rule out global polyuria (GP) in men. This study determines the sensitivity of indices for nocturnal polyuria (NP), defined as nocturnal polyuria index (NPi; nocturnal urine volume/24-hour urine volume) ≥0.33 or NUP ≥90 mL/hr, for detecting GP in women.

METHODS

Data were analyzed from 2 prospective protocols involving subjects recruited from a urology ambulatory care unit and a continence clinic. Women ≥18 years with nocturia were included if they met either of 2 common criteria for GP: (1) ≥40 mL/kg/24 hr or (2) ≥3,000 mL/24 hr.

RESULTS

Thirty-one women were included (NPi, 28.6 [21.3-40.7]; NUP, 100.8 [68.3-135.8] mL/hr). At the ≥40 mL/kg/24-hr cutoff, 40% and 63% of women reporting ≥1 nocturnal void(s) (n=30) had NPi ≥0.33 and NUP ≥90 mL/hr, respectively. Additionally, 53% and 71% of subjects reporting ≥2 nocturnal voids (n=17) had NPi ≥0.33 and NUP ≥90 mL/hr, respectively. At the ≥3,000 mL/24-hr cutoff, 38% and 69% of women reporting ≥1 nocturnal void(s) (n=13) had NPi ≥0.33 and NUP ≥90 mL/hr, respectively, and 63% and 88% of subjects reporting ≥2 nocturnal voids (n=8) had NPi ≥0.33 and NUP ≥90 mL/hr, respectively. By extension, 37%-62% of women with nocturia and GP did not have NP by NPi ≥0.33 criteria, and 12%-37% did not have NP by NUP ≥90 mL/hr criteria.

CONCLUSION

Indices of excess nighttime urination do not reliably predict GP in women. A full-length voiding diary may be particularly important in the evaluation of women with nocturia. Nocturia in women merits further consideration as a distinct entity.

Association between nocturia and frailty among elderly males in a veterans administration population

BACKGROUND

The relationship between frailty and nocturnal voiding is poorly understood.

AIM

To characterize the association between frailty, as defined by a frailty index (FI) based upon the Canadian Study of Health and Aging (CSHA) criteria, and nocturia, defined by measures of nocturnal urine production.

METHODS

Real-world retrospective analysis of voiding diaries from elderly males with lower urinary tract symptoms (LUTS) at an outpatient urology clinic. Males ≥ 65 years with ≥ 2 nocturnal voids were included. A modified FI was calculated from the LUTS database, which captured 39 variables from the original CSHA FI. Patients were divided into 3 groups by modified FI: low (≤ 0.077) (n = 59), intermediate (> 0.077 and < 0.179) (n = 58), and high (≥ 0.179) (n = 41). Diary parameters were compared using the Kruskal-Wallis test and pairwise comparisons with the Wilcoxon rank-sum test and Bonferroni adjustment.

RESULTS

The high frailty group was characterized by higher nocturnal urine volume (NUV), maximum voided volume (MVV), nocturnal maximum voided volume (NMVV), and nocturnal urine production (NUP). The presence of comorbid diabetes mellitus did not explain this effect.

CONCLUSION

Elderly males seeking treatment for LUTS with a high frailty burden are disproportionately affected by excess nocturnal urine production. Future research on the mechanistic relationship between urine production and functional impairment is warranted.

Associations between nighttime and daytime maximum voided volumes: Relevance for nocturia?

AIM

The relationship between maximum voided volumes (MVV) during the night and day is poorly understood. Such measurements are important because they are often used to indicate functional bladder capacity (FBC), a relevant parameter for nocturia. This study examined the association of such nighttime and daytime measurements in men with nocturia.

METHODS

We retrospectively analyzed 356 24-hour voiding diaries showing ≥2 nocturnal voids from 220 men at an outpatient urology clinic. We defined small FBC as MVV ≤ 200 mL.

RESULTS

A total of 131 entries demonstrated a nocturnal MVV ≤ 200 mL, of which a majority (98 [74.8%]) also showed a 24-hour MVV ≤ 200 mL (ie, global small FBC), and 33 (25.2%) exceeded the 200 mL threshold during the day (ie, nocturnal-specific small FBC). Correspondingly, among voiding diaries without global small FBC (n = 258), most (225/258 [87.2%]) showed a nocturnal MVV > 200 mL. Data were similar when analyzing only the first complete voiding diary per case, when limiting analyses to those without benign prostatic obstruction, and when limiting analyses to cases with nocturnal polyuria.

CONCLUSION

Nocturia may be attributable to nocturnal-specific small FBC or global small FBC. Although the etiology of nocturnal-specific small FBC remains unclear, it was present in a significant minority of patients with small FBC, thus necessitating more directed research. Conversely, diminished nocturnal MVV was nevertheless relatively uncommon in the absence of global small FBC, such that nocturnal-only voiding diaries may provide a rational alternative for follow-up evaluation in patients with nocturia due to global small bladder capacity.

Cardiovascular risk independently predicts small functional bladder storage capacity

PURPOSE

We aimed to determine the potential relationship between atherosclerotic cardiovascular disease (ASCVD) score, which equates to 10-year risk of atherosclerotic cardiovascular events, and functional bladder capacity (FBC) among men in the outpatient urology setting.

METHODS

We secondarily analyzed voiding diaries from men aged 40 to 79 years with nocturia. Patients with a history of cardiovascular disease or who had nocturnal polyuria were excluded. Patients were stratified by whether they met the high-risk ASCVD threshold (≥ 20%) following current cardiology consensus guidelines and assessed for the presence of small FBC (24-h maximum voided volume ≤ 200 ml). Logistic regression analyses were employed to explore associations between small FBC and ASCVD.

RESULTS

Eighty-four men (median ASCVD score 18.4 [IQR 12.8-26.9] %, age 66 [61-71] years, body mass index [BMI] 29.4 [26.4-32.7] kg/m²) were included, of whom 36 (42.9%) were high-risk and 48 (57.1%) fell below the high-risk threshold. High-risk patients were more likely to have small FBC (23 [63.9%] vs. 14 [29.2%], p = 0.002). ASCVD risk predicted small FBC on univariate analysis (p = 0.002). No such effect was observed with age (p = 0.116), BMI (p = 0.523), or benign prostatic obstruction (p = 0.180). The association between ASCVD risk and small FBC persisted on multivariate analysis after controlling for BMI and benign prostatic obstruction (p = 0.002). No significant predictors of small FBC were observed when age, a major determinant of ASCVD risk and independent correlate of small FBC, was substituted for ASCVD score (p = 0.108).

CONCLUSIONS

Small FBC is related to a higher predicted cardiovascular event rate in men with nocturia.

Assessment of the Most Impactful Combination of Factors Associated with Nocturia and to Define Nocturnal Polyuria by Multivariate Modelling

BACKGROUND

Nocturia is common and associated with multiple disease states. Many potential mechanisms have been proposed for nocturia, which also remains challenging to manage.

PURPOSE

To use multivariate analysis to determine which combinations of factors can accurately discriminate clinically significant nocturia in patients to facilitate clinical management and treatment decisions.

PATIENTS AND METHODS

Data analysis was based on frequency volume charts from three randomized controlled trials. There were 1479 patients included, of which 215 patients had no/mild nocturia and 1264 had clinically significant nocturia with at least two voids per night. Factors studied that may influence nocturia were demographics, sleep duration, functional bladder capacity, 24 h urine volume and literature-suggested definitions of nocturnal polyuria. We used univariate analysis and cross-validated multivariate modelling to assess association between factors and nocturia status, redundancy between factors and whether the combined use of factors could explain patients' nocturia status.

RESULTS

The multivariate analyses showed that the most useful definitions of nocturia are 'Nocturia Index' (NI) and 'Nocturnal Urine Production per hour' (NUPh) in combination with functional bladder capacity and sleep duration. Published definitions providing binary nocturnal polyuria outcomes had lower performance than continuous indices. These analyses also showed that NI was not specific to nocturnal polyuria as it also captured nocturia due to low functional bladder capacity. By contrast, NUPh was demonstrated to be specific to nocturnal polyuria.

CONCLUSION

NUPh has previously been shown among elderly males to be essential in nocturia and a very valid measure of nocturnal polyuria. However, the current, large and independent dataset now confirms that it can be applied in an adult population with a complaint of nocturia covering both males and females.

PRImary care Management of lower Urinary tract Symptoms in men: protocol for development and validation of a diagnostic and clinical decision support tool (the PriMUS study)

INTRODUCTION

Lower urinary tract symptoms (LUTS) is a bothersome condition affecting older men which can lead to poor quality of life. General practitioners (GPs) currently have no easily available assessment tools to help effectively diagnose causes of LUTS and aid discussion of treatment with patients. Men are frequently referred to urology specialists who often recommend treatments that could have been initiated in primary care. GP access to simple, accurate tests and clinician decision tools are needed to facilitate accurate and effective patient management of LUTS in primary care.

METHODS AND ANALYSIS

PRImary care Management of lower Urinary tract Symptoms (PriMUS) is a prospective diagnostic accuracy study based in primary care. The study will determine which of a number of index tests used in combination best predict three urodynamic observations in men who present to their GP with LUTS. These are detrusor overactivity, bladder outlet obstruction and/or detrusor underactivity. Two cohorts of participants, one for development of the prototype diagnostic tool and other for validation, will undergo a series of simple index tests and the invasive reference standard (invasive urodynamics). We will develop and validate three diagnostic prediction models based on each condition and then combine them with management recommendations to form a clinical decision support tool.

ETHICS AND DISSEMINATION

Ethics approval is from the Wales Research Ethics Committee 6. Findings will be disseminated through peer-reviewed journals and conferences, and results will be of interest to professional and patient stakeholders.

TRIAL REGISTRATION NUMBER

ISRCTN10327305.

Prevalence of the nocturnal polyuria syndrome in men

AIMS

Nocturnal polyuria (NP) is caused by a wide array of factors, including genitourinary and systemic comorbidities, modifiable behavior, and pharmaceuticals. When an identifying factor is absent, NP may be purely a symptom of the nocturnal polyuria syndrome (NPS) and secondary to blunting of normal arginine vasopressin action within the circadian rhythm. The purpose of this study is to determine the prevalence of NPS in male patients attending a Veterans Affairs outpatient urology clinic.

METHODS

Retrospective database analysis was performed of voiding diaries from men who had established care for lower urinary tract symptoms from 2007 to 2018. Patients were excluded if they reported fewer than two nocturnal voids on voiding diary analysis or had comorbidity associated with NP. Distinct cutoffs were separately employed to identify NP: nocturnal polyuria index (NPi; calculated as nocturnal urine volume divided by 24-hour urine volume) greater than 0.33; and nocturnal urine production (NUP) greater than 90 mL/h.

RESULTS

A total of 283 completed voiding diaries were evaluated and 202 patients had ≥2 nocturnal voids. After exclusions, at NPi greater than 33, the floor and ceiling NPS prevalence values were 21% and 41%, respectively. At NUP greater than 90 mL/h, the floor and ceiling NPS prevalence values were 17% and 32%, respectively.

CONCLUSIONS

The prevalence of NPS in patients with nocturia in the present study lies between 17% and 41%. NPS constitutes a clinically relevant subgroup of nocturia among male patients in the Veterans Affairs outpatient urology setting.

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.

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.

The International Continence Society (ICS) report on the terminology for adult male lower urinary tract and pelvic floor symptoms and dysfunction

INTRODUCTION

In the development of terminology of the lower urinary tract, due to its increasing complexity, the terminology for male lower urinary tract and pelvic floor symptoms and dysfunction needs to be updated using a male-specific approach and via a clinically-based consensus report.

METHODS

This report combines the input of members of the Standardisation Committee of the International Continence Society (ICS) in a Working Group with recognized experts in the field, assisted by many external referees. Appropriate core clinical categories and a subclassification were developed to give a numeric coding to each definition. An extensive process of 22 rounds of internal and external review was developed to exhaustively examine each definition, with decision-making by collective opinion (consensus).

RESULTS

A Terminology Report for male lower urinary tract and pelvic floor symptoms and dysfunction, encompassing around 390 separate definitions/descriptors, has been developed. It is clinically-based with the most common diagnoses defined. Clarity and user-friendliness have been key aims to make it interpretable by practitioners and trainees in all the different specialty groups involved in male lower urinary tract and pelvic floor dysfunction. Male-specific imaging (ultrasound, radiology, CT, and MRI) has been a major addition whilst appropriate figures have been included to supplement and help clarify the text.

CONCLUSIONS

A consensus-based Terminology Report for male lower urinary tract and pelvic floor symptoms and dysfunction has been produced aimed at being a significant aid to clinical practice and a stimulus for research.

International Continence Society (ICS) report on the terminology for nocturia and nocturnal lower urinary tract function

INTRODUCTION

The terminology for nocturia and nocturnal lower urinary tract function is reviewed and updated in a clinically and practically-based consensus report.

METHODS

This report has been created by a Working Group under the auspices and guidelines of the International Continence Society (ICS) Standardisation Steering Committee (SSC). All relevant definitions were updated on the basis of research over the last 16 years since the publication of the first nocturia standardization document in 2002. An extensive process of 16 rounds of internal and external reviews was involved to examine each definition exhaustively, with decision-making by collective opinion (consensus).

RESULTS

A clinically-based terminology report for nocturia and nocturnal lower urinary tract function, encompassing five key definitions divided into signs and symptoms has been developed. Clarity and user-friendliness have been key aims to make it interpretable by healthcare professionals and allied healthcare practitioners involved in the care of individuals with nocturnal lower urinary tract function.

CONCLUSION

A consensus-based terminology report for nocturia and nocturnal lower urinary tract function has been produced to aid clinical practice and research.

Nocturnal polyuria: Literature review of definition, pathophysiology, investigations and treatment

Nocturnal polyuria (NP) is characterised by increased urine production overnight in comparison to daytime. It has significant adverse events in adults including reduced quality of life, increased risk of falls and increased mortality.

Although NP can be a manifestation of other significant conditions like heart failure and sleep apnoea, there are lots of unanswered questions about NP. What is the underlying pathophysiology? Is NP a physiological manifestation of ageing? Is the circadian change of vasopressin release the primary pathology? Or is it a secondary phenomenon to a low diurnal production of urine? Is the primary pathology at the kidney level or is there another humoral, cardiac, or endovascular element? In this article, we summarise the available English-language literature on the subject of NP, including its epidemiology, pathogenesis, diagnosis and treatment.

Level of evidence: Not applicable for this multicentre audit.

Systematic review of proposed definitions of nocturnal polyuria and population-based evidence of their diagnostic accuracy

Background Evidence of diagnostic accuracy for proposed definitions of nocturnal polyuria is currently unclear. Purpose Systematic review to determine population-based evidence of the diagnostic accuracy of proposed definitions of nocturnal polyuria based on data from frequency-volume charts. Methods Seventeen pre-specified search terms identified 351 unique investigations published from 1990 to 2016 in BIOSIS, Embase, Embase Alerts, International Pharmaceutical Abstract, Medline, and Cochrane. Thirteen original communications were included in this review based on pre-specified exclusion criteria. Data were extracted from each paper regarding subject age, sex, ethnicity, health status, sample size, data collection methods, and diagnostic discrimination of proposed definitions including sensitivity, specificity, positive and negative predictive value. Results The sample size of study cohorts, participant age, sex, ethnicity, and health status varied considerably in 13 studies reporting on the diagnostic performance of seven different definitions of nocturnal polyuria using frequency-volume chart data from 4968 participants. Most study cohorts were small, mono-ethnic, including only Caucasian males aged 50 or higher with primary or secondary polyuria that were compared to a control group of healthy men without nocturia in prospective or retrospective settings. Proposed definitions had poor discriminatory accuracy in evaluations based on data from subjects independent from the original study cohorts with findings being similar regarding the most widely evaluated definition endorsed by ICS. Conclusions Diagnostic performance characteristics for proposed definitions of nocturnal polyuria show poor to modest discrimination and are not based on sufficient level of evidence from representative, multi-ethnic population-based data from both females and males of all adult ages.

Nocturia: consequences, classification, and management

Nocturia is a widespread condition that can negatively impact quality of sleep and overall health. This condition is multifactorial in nature and is best approached through the analysis of frequency volume charts. Through these charts, clinicians may classify each individual case of nocturia into one of four distinct categories: global polyuria, nocturnal polyuria, reduced bladder capacity, and mixed. Treatments should then be tailored to each individual based upon the category of their nocturia. In some cases, appropriate therapy will consist of behavioral modification techniques or addressing underlying systemic diseases. In other cases, medical therapy may be necessary, but, to date, medications have shown limited efficacy at treating nocturia.

Does the Age of Donor Kidneys Affect Nocturnal Polyuria in Patients With Successful Real Transplantation?

BACKGROUND

We investigated whether the age of donor kidneys influences the incidence of nocturnal polyuria in patients with successful renal transplantation (RTX).

METHODS

Eighty-five patients (45 men and 40 women) undergoing RTX (median age, 47 years) were included in this study. Twenty-four-hour bladder diaries were kept for 3 days, and nocturnal polyuria was defined as a nocturnal polyuria index (nocturnal urine volume/24-hour urine volume) of >0.33. Risk factors for nocturnal polyuria were analyzed in patients with RTX by means of the Mann-Whitney U test, χ² test, and a logistic regression analysis.

RESULTS

End-stage renal disease (ESRD) developed from diabetes mellitus in 16 patients (19%). Sixty-five patients (76%) received pre-transplant dialysis, with a median duration of 5 years. The median serum creatinine level and body mass index at the most recent visit were 1.2 mg/dL and 21.2 kg/m², respectively. On the basis of the 24-hour bladder diaries, nocturnal polyuria was identified in 48 patients (56%). A logistic regression analysis revealed that diabetes mellitus as the original disease for ESRD was the only risk factor for nocturnal polyuria (odds ratio, 8.95; 95% confidence interval, 2.01-65.3; P = .0028). The age of donor kidneys at examination did not affect the incidence of nocturnal polyuria (P = .9402).

CONCLUSIONS

Nocturnal polyuria was not uncommon in patients with successful RTX. Diabetes mellitus as the original disease for ESRD was the only risk factor for nocturnal polyuria, whereas the age of donor kidneys at examination did not affect the incidence of nocturnal polyuria. Thus, nocturnal polyuria is caused by recipient factors but not donor factors.

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.

Voiding dysfunction in older men

PURPOSE OF REVIEW

Voiding dysfunction in older men is an important health issue, with significant morbidity and biosocioeconomic burden. Treatment decisions are increasingly complex as many older men also suffer concurrent comorbidities and polypharmacy. A relatively sparse number of publications specifically examine this relevant topic.

RECENT FINDINGS

Common geriatric voiding syndromes include overactive bladder (OAB) and underactive bladder, with nocturia and incontinence often the most bothersome lower urinary tract symptoms, and may represent a falls risk together with OAB and incontinence. The combination of detrusor overactivity and impaired contractility may coexist in older patients and can be particularly difficult to diagnose and treat clinically. A small but not insignificant proportion of older men experience spontaneous remission of OAB symptoms without treatment, and 'watchful waiting' may be a reasonable option. OAB treatment with mirabegron may have a preferable side-effect profile compared with anticholinergics in older men. Intravesical onabotulinum toxin A is effective but risk of retention is greater in the older adults. Benign prostatic obstruction (BPO) and underactive bladder may lead to urinary retention, necessitating surgery or catheterization. BPO surgery is a reasonable option in older men, with realistic counselling of postoperative expectations. Combination BPO surgery and medical OAB treatment is suitable for detrusor overactivity and impaired contractility. Stress incontinence in older patients is usually iatrogenic and treatment can include continence applicances, urethral bulking agents, suburethral sling or artificial urinary sphincter.

SUMMARY

Management of voiding dysfunction in older patients need to take into account multiple factors including symptomatic and functional impairment, cognition, comorbidities and polypharmacy. Future research examining pathophysiology and treatment outcomes of voiding dysfunction in the older patient population is increasingly relevant.

Nocturia: aetiology and treatment in adults

Nocturia is an extremely common condition that has major sequelae for affected patients. Through disruption of sleep, nocturia impairs quality of life and worsens health outcomes, and is associated with a variety of morbidities including diabetes, coronary artery disease, obstructive sleep apnoea, obesity, metabolic syndrome, and depression. Unsurprisingly, several studies have also linked nocturia with reduced survival. Nocturia is not simply a consequence of lower urinary tract disease; rather, it is a multifactorial disorder that is often a manifestation of an underlying renal or systemic disease. Through the use of the frequency volume chart, clinicians can accurately quantify nocturia and determine its aetiology. Evaluation of quality of life and sleep using simple measures is essential in order to assess the impact of nocturia on a patient. Numerous treatment options for nocturia exist, but most are associated with minor benefit or lack sufficient evidence supporting their use. By systematically analysing an individual's causes of nocturia, clinicians can design appropriate treatment strategies to most effectively treat this condition.

Would a new definition and classification of nocturia and nocturnal polyuria improve our management of patients? ICI-RS 2014

The following is a report of the proceedings of the Nocturia Think Tank sessions of the annual International Consultation on Incontinence-Research Society, which took place September 22-24, 2014 in Bristol, UK. The report is organized into sections pertaining to the main topic of discussion focussing on the question as to whether a new definition and classification of nocturia and nocturnal polyuria would improve the outcome of management in our patients. First, discussions identified theoretical and practical shortcomings of current definitions. Secondly, the utility of several nocturnal polyuria definitions was tested in a real life population in relation to the symptom nocturia, in order to display weaknesses of these definitions. Thirdly, we explored in a clinical population the utility of bladder diary based parameters by asking the question: when nocturia improves, which of these parameters improve most? Based on the above explorations the Think Tank summarized elements of the current definitions that need reconsideration and suggests proposals for further research to reach more practical and more clinically meaningful definitions.

Impact of the International Continence Society (ICS) report on the standardisation of terminology in nocturia on the quality of reports on nocturia and nocturnal polyuria: a systematic review

OBJECTIVE

To systematically review and evaluate the impact of the International Continence Society (ICS)-2002 report on standardisation of terminology in nocturia, on publications reporting on nocturia and nocturnal polyuria (NP). In 2002, the ICS defined NP as a Nocturnal Polyuria Index (nocturnal urine volume/total 24-h urine volume) of >0.2-0.33, depending on age.

MATERIALS AND METHODS

In April 2013 the PubMed and Embase databases were searched for studies (in English, German, French or Dutch) based on original data and adult participants, investigating the relationship between nocturia and NP. A methodological quality assessment was performed, including scores on external validity, internal validity and informativeness. Quality scores of items were compared between studies published before and after the ICS-2002 report.

RESULTS

The search yielded 78 publications based on 66 studies. Quality scores of studies were generally high for internal validity (median 5, interquartile range [IQR] 4-6) but low for external validity. After publication of the ICS-2002 report, external validity showed a significant change from 1 (IQR 1-2) to 2 (IQR 1-2.5; P = 0.019). Nocturia remained undefined in 12 studies. In all, 19 different definitions were used for NP, most often being the ICS (or similar) definition: this covered 52% (n = 11) of studies before and 66% (n = 27) after the ICS-2002 report. Clear definitions of both nocturia and NP were identified in 67% and 76% before, and in 88% and 88% of the studies after the ICS-2002 report, respectively.

CONCLUSION

The ICS-2002 report on standardisation of terminology in nocturia appears to have had a beneficial impact on reporting definitions of nocturia and NP, enabling better interpretation of results and comparisons between research projects. Because the external validity of most of the 66 studies is considered a problem, the results of these studies may not be validly extrapolated to other populations. The ICS definition of NP is used most often. However, its discriminative value seems limited due to the estimated difference of 0.6 nocturnal voids between individuals with and without NP. Refinement of current definitions based on robust research is required. Based on pathophysiological reasoning, we argue that it may be more appropriate to define NP based on nocturnal urine production or nocturnal voided volumes, rather than on a diurnal urine production pattern.