Polyuria in patients with lower urinary tract symptoms: Prevalence and etiology.

INTRODUCTION: Patients with lower urinary tract symptoms (LUTS) can be subcategorized into polyuria, normal or oliguria groups. Polyuria may be caused by pathologies including diabetes mellitus (DM), chronic kidney disease (CKD), diabetes insipidus (DI), or primary polydipsia (PPD). While fluid restriction is appropriate for some, doing so in all may result in serious complications. This study investigates the prevalence of these pathologies in LUTS patients with polyuria. MATERIALS AND METHODS: Two databases were retrospectively queried for men and women who filled out a lower urinary tract symptom score (LUTSS) questionnaire, 24-h bladder diary (24HBD) and were polyuric (>2.5 L/day). Patients were divided into four groups: poorly controlled DM, DI, an CKD grade 3 and PPD. One-way analysis of variance compared 24HBD and LUTSS questionnaires. Pearson correlation examined LUTSS and bother with 24-h voided volume (24 HVV), maximum voided volume (MVV) and total voids. RESULTS: Among 814 patients who completed a 24HBD, 176 had polyuria (22%). Of the patients with complete data, 7.8% had poorly-controlled DM, 3.1% had DI, 4.7% had CKD grade 3% and 84.4% had PPD. Amongst the four different sub-groups, significant differences were seen in 24 HVV (p < 0.001), nocturnal urine volume (NUV) (p < 0.001), MVV (p = 0.003), daytime voids (p = 0.05), nocturnal polyuria index (NPi) (p < 0.001) and nocturia index (Ni) (p = 0.002). Significance was also seen between LUTSS and bother subscore (r = 0.68, p < 0.001), LUTSS and total voids (r = 0.29, p = 0.001) and bother sub-score and total voids (r = 0.21, p = 0.019). CONCLUSIONS: 22% of patients with LUTS were found to have polyuria based on a 24HBD. Within this cohort, four sub-populations were identified as being demonstrating statistically significant differences in 24 HVV, NUV, MVV, daytime voids, NPi and Ni. Identifying the underlying etiology of polyuria should be carried out to safely treat patients with LUTS.

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.

Prevalence and predictors of nocturnal polyuria in females with overactive bladder syndrome.

PURPOSE: To describe the prevalence and predictors of nocturnal polyuria (NP) in women with overactive bladder syndrome (OAB). METHODS: Between July 2009 and January 2018, women with OAB were enrolled. NP was defined when the nocturnal polyuria index (NPI) (nighttime voided volume over 24-h voided volume) was > 33% (NPI33) in women ≥ 65 years-old and > 20% (NPI20) in women < 65 years old. Repeated analysis was also performed for NP defined by the NPI33 definition at all ages. RESULTS: A total of 1071 women with OAB were analyzed. The overall prevalence of NP was 30% (319/1071), with the highest prevalence in women in the perimenopausal period (46-50 years old), while NP was diagnosed by age-dependent NPI. The overall prevalence of NP was 12% (128/1071), with an increasing trend with increasing age, while NP was diagnosed by the NPI33 definition only. Daytime frequency and nocturia episodes were both predictors for NP in both definitions. Receiver operating characteristic curve analysis revealed that more than 5 nocturia episodes noted in the 3-day bladder diary were an optimal cutoff value to predict nocturnal polyuria [(sensitivity = 85.6%, specificity = 61.0%; area = 0.80, 95% CI 0.77-0.82) and (sensitivity = 88.3%, specificity = 65.9%; area = 0.83, 95% CI 0.80-0.85), respectively, in the two definitions]. CONCLUSIONS: NP is common in women with OAB, especially in women with more than 5 nocturia episodes in their 3-day bladder diaries, and adjuvant therapy for better treatment efficacy is needed.

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.

Prevalence, subtypes, and correlates of nocturia in the symptoms of Lower Urinary Tract Dysfunction Research Network cohort.

AIMS: We determined the prevalence, severity, and correlates of nocturia in a large clinical cohort of patients. METHODS: Patients presenting with lower urinary tract symptoms (LUTS) completed 3-day bladder diaries. Nocturia was quantified based on the mean number of nighttime voids documented over the 3 days. Nocturia subtypes (global polyuria, nocturnal polyuria [NP], reduced global bladder capacity, and reduced nocturnal bladder capacity) were assessed. Bother due to nocturia was measured by the LUTS Tool. Sleep quality was assessed with the Patient-Reported Outcomes Measurement Information System Sleep Scale. Multivariable multinomial regression was used to explore patient characteristics associated with nocturia. RESULTS: In 502 participants with analyzable diaries (285 men and 217 women), the mean number of nocturia episodes over 3 days was 0 in 103 (20.5%), >0 to <1 in 151 (20.1%), 1 to <2 in 165 (32.9%), and ≥2 in 83 (16.5%). Sixty-seven percent of the participants with nocturia ≥1 reported significant bother from their nocturia. NP was the most common nocturia subtype and was present in 17% of those with nocturia = 0, 40% of those with nocturia >0 to <1, 65% of those with nocturia 1 to <2%, and 77% with nocturia 2+. Higher degrees of nocturia were associated with male sex, greater sleep disturbance, and a higher likelihood of exhibiting multiple nocturia subtypes. CONCLUSIONS: Nocturia ≥1 occurred in 49% of LUTS patients and caused significant bother in the majority of them. The most common subtype was NP, but a substantial proportion of patients exhibited additional characteristics.

Nocturnal Polyuria and Hypertension in Patients with Lifestyle Related Diseases and Overactive Bladder.

PURPOSE: The objective of this multicenter cross-sectional study was to investigate the relationship of nocturnal polyuria in patients with common lifestyle related diseases and overactive bladder, with special attention to hypertension. MATERIALS AND METHODS: After baseline assessment, patients recorded 24-hour urinary frequency/volume, blood pressure and heart rate for 3 days. They were stratified into 4 groups based on mean blood pressure, including no hypertension, and controllable, untreated and uncontrolled hypertension, respectively. RESULTS: The 2,353 eligible patients, who had urinary urgency once or more per week and 1 or more nocturnal toilet visits, were enrolled from 543 sites in Japan. Of these patients complete data, including the 24-hour frequency volume chart, were collected from 1,271. Multivariable analyses showed a statistically significant association of nocturnal polyuria with increasing age (OR 1.04, 95% CI 1.02-1.05, p <0.001) and gender (women vs men OR 0.75, 95% CI 0.59-0.96, p = 0.02), and for controllable (OR 1.10, 95% CI 0.83-1.460), untreated (OR 2.62, 95% CI 1.55-4.45) and uncontrolled (OR 1.15, 95% CI 0.81-1.62) hypertension vs no hypertension (p = 0.005). However, when assessed separately in men and women, hypertension and heart rate were significantly associated with nocturnal polyuria in women alone (p = 0.01 and 0.03, respectively). Lower urinary tract symptoms suggestive of benign prostatic hyperplasia were significantly associated with nocturnal polyuria in men alone (p <0.001). CONCLUSIONS: The current study demonstrates that nocturnal polyuria was significantly associated with age, male gender, and untreated hypertension in patients with lifestyle related diseases and overactive bladder. The association between hypertension and nocturnal polyuria was significant in women alone.

Diurnal blood pressure and urine production in acute spinal cord injury compared with controls.

STUDY DESIGN: This is a prospective observational study. OBJECTIVES: The objective of this study was to determine time-dependent changes in diurnal blood pressure (BP) and urine production in acute spinal cord injury (SCI). SETTING: This study was conducted in a specialist, state-based spinal cord service in Victoria, Australia. METHODS: Consenting patients admitted consecutively with acute SCI were compared with patients confined to bed rest while awaiting surgery and with mobilising able-bodied controls. Participants underwent ambulatory BP monitoring (ABPM), measurement of diurnal urine production and rated orthostatic symptoms over 1 year. Participants with night:day systolic BP (SBP) <90% were classified as dippers, 90-100% as non-dippers and >100% as reverse dippers. RESULTS: Participants comprised tetraplegics (n=47, 40.0±17.3 years), paraplegics (n=35, 34.4±13.9 years), immobilised (n=18, 30.9±11.3 years) and mobilising (n=44, 33.1±13.5 years) controls. At baseline, 24-h BP was significantly lower in tetraplegics (111.8±1.9/62.1±1.1 mm Hg) but not in paraplegics (116.7± 1.4/66.0±1.1 mm Hg), compared with controls (117.1 ±1.3/69.1±1.1 mm Hg), adjusting for gender. This difference was not observed at 1 year. The average night:day SBP in mobilising controls was 86.1±0.7%, differing from paraplegics (94.0±1.5%, P<0.001) and tetraplegics (101.5±1.5%, P<0.001). Urine production in tetraplegics and paraplegics did not fall at night compared with the day. Abnormal diurnal BP and orthostatic symptoms in tetraplegics persisted throughout the study. Nocturnal hypertension was observed in 27% (n=9) of tetraplegics, of whom only 2 had day hypertension. All mobilising controls with nocturnal hypertension (n=6, 14%) had day hypertension. CONCLUSION: People with SCI have a high prevalence of isolated nocturnal hypertension, reverse dipping, orthostatic intolerance and nocturnal polyuria. Cardiovascular risk management and assessment of orthostatic symptoms should include ABPM.

INCIDENCE OF CENTRAL DIABETES INSIPIDUS IN CHILDREN PRESENTING WITH POLYDIPSIA AND POLYURIA.

OBJECTIVE: Polydipsia and polyuria are common reasons for referral to the Pediatric Endocrine clinic. In the absence of hyperglycemia, diabetes insipidus (DI) should be considered. The objectives of the study were to determine the prevalence of central DI (CDI) in a group of children presenting for evaluation of polydipsia and polyuria, and to determine if predictive features were present in patients in whom the diagnosis of DI was made. METHODS: The study was a retrospective chart review of children presenting to the endocrine clinic with complaints of polydipsia and polyuria over a 5-year period. RESULTS: The charts of 41 patients (mean age 4.9 ± 3.7 years, 28 males) were reviewed. CDI was diagnosed in 8 (20%) children based on abnormal water deprivation test (WDT) results. All but one patient had abnormal magnetic resonance imaging (MRI) findings, the most common being pituitary stalk thickening. Children with DI were older (7.86 ± 4.40 vs. 4.18 ± 3.20 years, P = .01) and had a higher propensity for cold beverages intake and unusual water-seeking behaviors compared to those without DI. Baseline WDT also revealed higher serum sodium (Na) and osmolality. CONCLUSION: The incidence of CDI in children presenting with polydipsia and polyuria is low. Factors associated with higher likelihood of pathology include older age, propensity for cold beverage intake, and higher baseline serum Na and osmolality on a WDT. ABBREVIATIONS: BMI = body mass index CDI = central diabetes insipidus DI = diabetes insipidus Na = sodium WDT = water deprivation test.

Diagnostic Accuracy of Tests for Polyuria in Lithium-Treated Patients.

In lithium-treated patients, polyuria increases the risk of dehydration and lithium toxicity. If detected early, it is reversible. Despite its prevalence and associated morbidity in clinical practice, it remains underrecognized and therefore undertreated. The 24-hour urine collection is limited by its convenience and practicality. This study explores the diagnostic accuracy of alternative tests such as questionnaires on subjective polyuria, polydipsia, nocturia (dichotomous and ordinal responses), early morning urine sample osmolality (EMUO), and fluid intake record (FIR). This is a cross-sectional study of 179 lithium-treated patients attending a general adult and an old age psychiatry service. Participants completed the tests after completing an accurate 24-hour urine collection. The diagnostic accuracy of the individual tests was explored using the appropriate statistical techniques. Seventy-nine participants completed all of the tests. Polydipsia severity, EMUO, and FIR significantly differentiated the participants with polyuria (area under the receiver operating characteristic curve of 0.646, 0.760, and 0.846, respectively). Of the tests investigated, the FIR made the largest significant change in the probability that a patient experiences polyuria (<2000 mL/24 hours; interval likelihood ratio, 0.18 and >3500 mL/24 hours; interval likelihood ratio, 14). Symptomatic questioning, EMUO, and an FIR could be used in clinical practice to inform the prescriber of the probability that a lithium-treated patient is experiencing polyuria.

Risk factors for polyuria in a cross-section of community psychiatric lithium-treated patients.

OBJECTIVES: Polyuria increases the risk of dehydration and lithium toxicity in lithium-treated patients. Risk factors have been inconsistently described and the variance of this adverse effect remains poorly understood. This study aimed to establish independent risk factors for polyuria in a community, secondary-level lithium-treated sample of patients. METHODS: This was a cross-sectional study of the lithium-treated patients attending a general adult and an old age psychiatry service. Participants completed a 24-hour urine collection. Urine volume and the presence of polyuria were the outcomes of interest. The relationship between outcome and the participant's demographic and clinical characteristics was explored with univariable and multivariable analysis. RESULTS: A total of 122 participants were included in the analysis, with 38% being diagnosed with polyuria. Female gender and increased body weight independently predicted the presence of polyuria (standardized regression coefficient 1.01 and 0.94, respectively; p = 0.002 and p = 0.003, respectively). Female gender and increased body weight, lithium dose, and duration of lithium treatment independently predicted higher 24-hour urine volumes (standardized regression coefficients 0.693, p < 0.0005; 0.791, p < 0.0005; 0.276, p = 0.043; 0.181, p = 0.034, respectively). Of three different weight metrics, lean body weight was the most predictive. CONCLUSIONS: Female gender and increased body weight explain part of the variance of this adverse effect. Both risk factors offer fresh insights into the pathophysiology of this potentially reversible and dangerous adverse effect of lithium treatment. Future research should focus on understanding the differences between the genders and between different body compositions in terms of lithium pharmacokinetics and pharmacodynamics.

The clinical pattern of diabetes Insipidus in a large university hospital in the Middle East.

Diabetes insipidus is a rare but serious endocrine disorder. Paediatric patients were evaluated for polyuria at King Khalid University Hospital, Riyadh, Saudi Arabia, over a decade (2000-13). Relevant clinical examination and/or a triad of high serum osmolality, hypernatremia and low urine osmolality due to increased urine output confirmed the diagnosis. Water deprivation test was required in some cases with non-classic presentations. Appropriate brain imaging was performed whenever central diabetes insipidus (CDI) was suspected. Twenty-eight patients, 15 males (53.6%) and 13 females (46.4%), aged 0-17 years (mean: 6 years) were included. The calculated period prevalence was 7 in 10,000. In our cohort, 60.7% (17 of 28 patients) had CDI, 21.4% (6 of 28) were diagnosed with nephrogenic diabetes insipidus (NDI) and 17.9% (5 of 30) had psychogenic polydipsia. CDI was due to variable aetiology. Though CDI was the commonest, NDI was not a rare encounter in our community, possibly because of high consanguineous marriages.

[Is nocturnal polyuria more frequent among patients with Parkinson's disease?]. / La polyurie nocturne est-elle plus fréquente chez les patients parkinsoniens?

OBJECTIVE: Nocturia is a frequent complaint in the population of idiopathic Parkinson's disease patients (IPD). The consequences of nocturia in the IPD population are at high importance as these patients have motor problems and therefore a risk of nocturnal fall. The aim of the study was to determine the mechanism of nocturia in patients with MPI, by determining the prevalence of nocturnal polyuria (NP) in this population. METHOD: A prospective study by bladder diary was conducted on 70 consecutive IPD patients consulting for regular neurological follow-up at a non-severe stage. Nocturia was defined as 1 or more awakenings to urinate. Two definitions of NP were used: nocturnal diuresis 33% or higher of the total diuresis (NUV33), which is the ICS (International Continence Society) definition, and nocturnal diuresis 90 mL/h or higher (NUP90). RESULTS: The mean patient age was 71 years (45-86, sex ratio 33/30). On average, patients were diagnosed for IPD 6.76 years earlier. The prevalence of NP was 64.5% according to NUV33 definition, and 17.7% according to NUP90 definition. Among patients with nocturia, the prevalence of NP was 66% (NUV33) and 21.5% (NUP90). No association was observed between disease duration of the IPD and the prevalence of nocturia and NP. Patients 70 years and older were more likely to have NP as defined by NUV33 than those less than 70 years (72.7% versus 55.17%, P=0.015). Men had more frequently nocturia (33.3% versus 20.7%, P=0.027). CONCLUSIONS: The prevalence of NP and nocturia was analyzed in patients with IPD at a non-severe stage. This prevalence was not higher than in the general population of the same age. The mechanism of nocturia in patients with IPD is not unambiguous and therefore requires to be explored by a bladder diary.

The association between nocturia and nocturnal polyuria in clinical and epidemiological studies: a systematic review and meta-analyses.

PURPOSE: We determined the relationship between nocturia and nocturnal polyuria. MATERIALS AND METHODS: The PubMed® and Embase® databases were searched for studies written in English, German, French or Dutch with original data on adult participants in an investigation of the relationship between nocturia and nocturnal polyuria. A meta-analysis of the difference in mean nocturnal voiding frequencies between patients with and without nocturnal polyuria was conducted. Nocturnal polyuria risk was compared between participants with and without nocturia, and the resulting odds ratio was subsequently converted to relative risk with 95% CIs. RESULTS: From 511 references identified we selected 78 publications of 66 studies, 15 of which met the inclusion criteria for this study. Quality scores of studies were generally high for internal validity but low for external validity. In 7 studies (1,416 participants) we estimated a standardized mean difference of 0.59 (95% CI 0.29-0.89) for nocturnal voids between nocturnal polyuria and nonnocturnal polyuria cases. In 8 other studies (with 2,320 participants) we calculated a pooled OR of 4.99 (3.92-6.37) for nocturnal polyuria in individuals with nocturia. The corresponding RR, based on a nocturnal polyuria risk in the pooled population of 63.8%, was 1.41 (1.37-1.44). CONCLUSIONS: The association between nocturia and nocturnal polyuria is apparent and robust. However, the clinical importance of the association appears to be less obvious than previously suggested based on single studies. The observed high prevalence of nocturnal polyuria, as a result of the applied International Continence Society definition, may be responsible for this discrepancy.

Safety, tolerability, pharmacokinetics and pharmacodynamics following 4 weeks' treatment with empagliflozin once daily in patients with type 2 diabetes.

AIM: To investigate the safety, tolerability, pharmacokinetics and pharmacodynamics of empagliflozin in patients with type 2 diabetes following oral administration of 10, 25 or 100 mg doses once daily over 28 days. METHODS: A total of 78 patients were assigned to empagliflozin 10 mg (n = 16), 25 mg (n = 16) or 100 mg (n = 30) or placebo (n = 16) for 28 days. Assessments included adverse events (AEs) and pharmacokinetic and pharmacodynamic endpoints. RESULTS: Empagliflozin exposure increased dose-proportionally over the dose range 10-100 mg and showed linear pharmacokinetics with respect to time. Urinary glucose excretion (UGE) increased from baseline to day 1 by 74, 90 and 81 g with empagliflozin 10, 25 and 100 mg, respectively. The increases in UGE were maintained over 28 days with multiple dosing. Virtually no change in UGE was observed in the placebo group. Significant reductions from baseline in mean daily plasma glucose and fasting plasma glucose were observed with empagliflozin compared with placebo. The incidence of AEs was similar in the empagliflozin and placebo groups (50.0, 56.3 and 66.7% with empagliflozin rising doses and 62.5% with placebo). The most frequently reported AEs were pollakiuria (10.3%), nasopharyngitis (9.0%), constipation (9.0%) and headache (7.7%). CONCLUSIONS: Oral administration of empagliflozin at doses of 10, 25 or 100 mg once daily over 28 days resulted in significant increases in UGE and reductions in blood glucose compared with placebo, and were well tolerated in patients with type 2 diabetes.

The prevalence and predictive factors of nocturnal polyuria in Japanese patients with nocturia: a multicentral retrospective cohort study.

The aims of this study were to determine the prevalence and predictors of nocturnal polyuria (NP) in Japanese patients. This multicentral, observational study enrolled patients with the chief complaint of nocturia at 17 Japanese institutions between January 2018 and December 2022. The frequency of daily voiding and volume of urination were evaluated using bladder diaries. NP was diagnosed in patients with an NP index of > 33%. The primary endpoint was NP prevalence in patients with nocturia. The secondary endpoints were the prevalence of NP according to sex and age and the identification of factors predicting NP. This study analyzed 875 eligible patients. NP was present in 590 (67.4%) patients, with prevalence rates of 66.6% and 70.0% in men and women, respectively. Age ≥ 78 years, body mass index (BMI) < 23.0 kg/m2, and patients with ischemic heart or cerebrovascular disease were significant predictors of NP (P < 0.001, P < 0.001, P = 0.014, P = 0.016, respectively). This is the first large multicenter study to investigate the prevalence of NP in Japanese patients with nocturia. NP has a prevalence of 67.4%. Significant predictors of NP include age, BMI, and cardiovascular disease.

A cutoff value based on analysis of a reference population decreases overestimation of the prevalence of nocturnal polyuria.

PURPOSE: We sought criteria for nocturnal polyuria in asymptomatic, nonurological adults of all ages by reporting reference values of the ratio of daytime and nighttime urine volumes, and finding nocturia predictors. MATERIALS AND METHODS: Data from a database of frequency-volume charts from a reference population of 894 nonurological, asymptomatic volunteers of all age groups were analyzed. The nocturnal polyuria index and the nocturia index were calculated and factors influencing these values were determined by multivariate analysis. RESULTS: The nocturnal polyuria index had wide variation but a normal distribution with a mean ± SD of 30% ± 12%. The 95th percentile of the values was 53%. Above this cutoff a patient had nocturnal polyuria. This value contrasts with the International Continence Society definition of 33% but agrees with several other reports. On multivariate regression analysis with the nocturnal polyuria index as the dependent variable sleeping time, maximum voided volume and age were the covariates. However, the increase in the nocturnal polyuria index by age was small. Excluding polyuria and nocturia from analysis did not alter the results in a relevant way. The nocturnal voiding frequency depended on sleeping time and maximum voided volume but most of all on the nocturia index. CONCLUSIONS: The prevalence of nocturnal polyuria is overestimated. We suggest a new cutoff value for the nocturnal polyuria index, that is nocturnal polyuria exists when the nocturnal polyuria index exceeds 53%. The nocturia index is the best predictor of nocturia.

Tamsulosin reduces nighttime urine production in benign prostatic hyperplasia patients with nocturnal polyuria: a prospective open-label long-term study using frequency-volume chart.

AIMS: The effects of tamsulosin treatment on changes in frequency-volume chart (FVC) data, especially nighttime urine production, over time were assessed, and the mechanisms underlying the improvement of nocturia in benign prostatic hyperplasia (BPH) patients with nocturnal polyuria (NP) are discussed. METHODS: A total of 104 patients with lower urinary tract symptoms secondary to BPH were enrolled. After enrollment in the study, the patients were treated with tamsulosin (0.2 mg) once daily. Visits were scheduled every 4 weeks until week 12 (month 3) after study entry, and then every 12 weeks subsequently. All patients completed the International Prostate Symptom Score (IPSS), quality of life (QOL) index, and 3-day FVC, and underwent uroflowmetry at enrollment and on each visit. RESULTS: Eighty-two patients (mean age: 70.9 ± 7.1 years) were analyzed for 24 months after treatment. Patients were divided into two groups, NP and nonNP, based on FVC outcome. The IPSS, QOL index, and maximum flow rate improved during the 24-month period after treatment in both groups. Mean daytime urine volume significantly increased in the NP group, but no changes were detected in the nonNP group. Mean nighttime urine frequency significantly decreased in the NP group over a 24-month period, and was associated with a significant decrease in nighttime urine volume that was not found in the nonNP group. Maximum voided volume increased most months after treatment in both groups. CONCLUSIONS: The present long-term prospective study using FVC demonstrated that tamsulosin reduced nighttime urine production in BPH patients with NP.

Analysis of changes in the pathophysiology of nocturia according to the number of nocturia episode, age, and gender using frequency volume charts: A retrospective observational study.

PURPOSE: To evaluate the pathophysiology of nocturia based on the frequency volume chart, and determine the risk factors for nocturia occurring ≥2 times per night. MATERIALS AND METHODS: In this retrospective study, we reviewed 311 patients with complaints of nocturia from January 2017 to February 2019 at our institution. Nocturnal polyuria (NP) and global polyuria (GP) were defined as NP index >0.35 regardless of age and 24 h urine volume >2.5 L/day, respectively. Decreased bladder capacity (dBC) was when the maximal voided volume was <325 mL. Decreased nocturnal bladder capacity (dNBC) was defined as nocturnal bladder capacity index >0. RESULTS: In total, 273 patients were included in the primary analyses. Of 802 days from 273 frequency volume charts, the median number of nocturia was 1 episode per day. Further, NP (odds ratios [OR] 7.01), GP (OR 4.25), dBC (OR 3.00), dNBC (OR 10.12), and age (OR 1.04) had the association with nocturia ≥2 times per night. There was a significant stepwise increase in NP, dNBC, dBC, and GP with the number of nocturia episodes. As patient age increased, the likelihood of NP (P < 0.001) and dBC (P < 0.001) being the cause for nocturia tended to increase, but that of dNBC (P = 0.022) and nocturia without cause (P = 0.007) tended to decrease. Moreover, dBC was more likely to cause nocturia in female patients than in male patients (P < 0.001). CONCLUSION: NP, dBC, dNBC, and GP are important factors involved in the pathophysiology of nocturia occurring ≥2 times per night.

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.