A Clinical Investigation of Nocturnal Polyuria in Patients With Nocturia: A Diurnal Variation in Arginine Vasopressin Secretion and its Relevance to Mean Blood Pressure

Obesity and Voiding Parameters in a Community-Based Population of Okinawa, Japan: Kumejima Digital Health Project (KDHP)

(1) Background: Evidence has accumulated regarding the etiology of lower urinary tract symptoms associated with obesity and metabolic syndrome. Therefore, the present study aimed to identify which subjectively and objectively measured voiding parameters were associated with obesity in a community-based population. (2) Methods: Voiding parameters on a self-administered questionnaire and a digital self-health monitoring system for urine excretion (s-HMSU) were compared between participants with and without obesity, defined as a body mass index ≥ 25 kg/m2 (n = 30 and 29, respectively), from a community in Okinawa, Japan. Logistic regression analysis was employed to calculate the odds ratios of abnormalities in voiding parameters for the obese group, with the non-obese group serving as a reference. (3) Results: The obese group had odds ratios of 5.17 (95% confidence interval: 1.33−20.0) for shortened hours of undisturbed sleep (<302 min) by s-HMSU and 7.65 (1.88−31.1) for nighttime urinary frequency by a questionnaire after adjusting for age and sex. In addition, the obese group had an adjusted odds ratio of 2.27 (0.76−6.78) for decreased maximum bladder capacity (<212 mL) by s-HMSU. (4) Conclusion: the results of the present study suggest that nocturia and shortened hours of undisturbed sleep are signs of obesity.

Evaluation of the influence of a history of childhood nocturnal enuresis on nighttime urinary frequency and the causes of nocturia in adults

OBJECTIVES

To examine whether a history of nocturnal enuresis affects nighttime urinary frequency and to evaluate nocturia etiologies in adults.

METHODS

A total of 143 participants with at least one episode of nocturia per night were included in this study. The self-reported questionnaire collected data on demographic characteristics, medical history, history of nocturnal enuresis in elementary school, lower urinary tract symptoms, and frequency-volume charts.

RESULTS

A history of nocturnal enuresis was observed in 52.4% of participants. However, night-time urinary frequency was significantly lower in participants with a history of nocturnal enuresis in elementary school than in those without such history. On multivariate analysis, a history of nocturnal enuresis was also negatively associated with nighttime urinary frequency (p<0.01). There was a collinearity effect between age and nighttime urinary frequency. A history of nocturnal enuresis did not affect the presence of nocturnal polyuria or overactive bladder in participants. However, sleep disturbances were fewer in participants with a history of nocturnal enuresis (odds ratio 0.404).

CONCLUSIONS

A history of nocturnal enuresis might be negatively associated with nighttime urinary frequency due to fewer sleep disturbances. Further, progression of nocturia may depend on conditions, such as age and acquired diseases.

Implications of Cardiovascular Disease for Assessment and Treatment of Nocturia in Primary Care: Systematic Review and Nominal Group Technique Consensus

CONTEXT

Heart conditions affect salt and water homeostasis as a consequence of the underlying condition, compensatory processes, and therapy, and can result in nocturnal polyuria. These processes need to be identified as part of a full evaluation of nocturia.

OBJECTIVE

To conduct a systematic review of nocturia in cardiovascular disease and achieve expert consensus for primary care management. Primary care was defined as a health care setting in which the expertise did not include specialist cardiology.

EVIDENCE ACQUISITION

Four databases were searched from January 2000 to April 2020. A total of 3524 titles and abstracts were screened and 27 studies underwent full-text screening. Of these, eight studies were included in the analysis. The nominal group technique (NGT) was used to achieve consensus among an expert panel incorporating public involvement.

EVIDENCE SYNTHESIS

Most studies focused on nocturia related to blood pressure (BP), while one investigated leg oedema. Hypertension, particularly overnight blood pressure above normal, corresponds with higher risk of nocturia. NGT identified fluid and salt overload, nondipping hypertension, and some therapeutic interventions as key nocturia contributors. History taking and examination should identify raised jugular venous pressure/ankle swelling, with relevant investigations including measurement of BP, resting electrocardiogram, and B-type natriuretic peptide. Treatment recommends reducing salt (including substitutes), alcohol and caffeine. Heart failure is managed according to local guidance and controlling fluid intake to 1-2 l daily. If there is no fluid retention, reduce or discontinue diuretics or calcium channel blockers and follow up to reassess the condition. The target clinic blood pressure is 140/90 mm Hg.

CONCLUSIONS

Cardiovascular disease and its treatment are influential for understanding nocturia. Management aims to identify and treat heart failure and/or hypertension.

PATIENT SUMMARY

People with cardiovascular disease can suffer severe sleep disturbance because of a need to pass urine at night due to increased overnight blood pressure or heart failure. Following a detailed evaluation of the published research, a group of experts recommended practical approaches for assessing and treating these issues.

Conformational selection of vasopressin upon V1a receptor binding

The neuropeptide vasopressin (VP) and its three G protein-coupled receptors (V_1aR, V_1bR and V₂R) are of high interest in a wide array of drug discovery programs. V_1aR is of particular importance due to its cardiovascular functions and diverse roles in the central nervous system. The structure–activity relationships underpinning ligand-receptor interactions remain however largely unclear, hindering rational drug design. This is not least due to the high structural flexibility of VP in its free as well as receptor-bound states. In this work, we developed a novel approach to reveal features of conformational selectivity upon VP-V_1aR complex formation. We employed virtual screening strategies to probe VP’s conformational space for transiently adopted structures that favor binding to V_1aR. To this end, we dissected the VP conformational space into three sub-ensembles, each containing distinct structural sets for VP’s three-residue C-terminal tail. We validated the computational results with experimental nuclear magnetic resonance (NMR) data and docked each sub-ensemble to V_1aR. We observed that the conformation of VP’s three-residue tail significantly modulated the complex dissociation constants. Solvent-exposed and proline trans-configured VP tail conformations bound to the receptor with three-fold enhanced affinities compared to compacted or cis-configured conformations. The solvent-exposed and more flexible structures facilitated unique interaction patterns between VP and V_1aR transmembrane helices 3, 4, and 6 which led to high binding energies. The presented “virtual conformational space screening” approach, integrated with NMR spectroscopy, thus enabled identification and characterization of a conformational selection-type complex formation mechanism that confers novel perspectives on targeting the VP-V_1aR interactions at the level of the encounter complex – an aspect that opens novel research avenues for understanding the functionality of the evolutionary selected conformational properties of VP, as well as guidance for ligand design strategies to provide more potent and selective VP analogues.

Long-term administration of alpha-1 blocker can reverse the micturition pattern in a bladder outlet obstruction murine model

OBJECTIVE

To investigate the effect of chronic administration of an alpha-1 blocker on micturition patterns in long-term partial bladder outlet obstruction.

METHODS

Mice were divided into three groups: a normal group, in which animals were fed a standard diet; a partial bladder outlet obstruction group, in which the proximal urethra was tied and animals were fed a standard diet; and a partial bladder outlet obstruction + naftopidil group, in which the proximal urethra was tied and animals were fed a standard diet containing naftopidil. Micturition behavior was evaluated in all groups for 6 months after partial bladder outlet obstruction surgery. The parameters evaluated included voided volume, time per void, urination frequency and total urine volume. Quantitative assessment of gene expression was also carried out.

RESULTS

Total urine volume, as well as total and average voided volume during night, was significantly decreased in partial bladder outlet obstruction + naftopidil mice compared with partial bladder outlet obstruction animals. The levels of transcripts encoding 5-hydroxytryptamine 2A and tissue inhibitor of metalloproteinase 2 were significantly decreased in the partial bladder outlet obstruction + naftopidil group compared with the partial bladder outlet obstruction group.

CONCLUSIONS

Long-term administration of an alpha-1 blocker seems to reverse the disturbance of the micturition pattern caused by partial bladder outlet obstruction. Mechanistically, this effect might be mediated by changes in the expression of a serotonin receptor and/or in the activity of the fibrogenesis pathway.

International Continence Society consensus on the diagnosis and treatment of nocturia

INTRODUCTION

Patients with nocturia have to face many hurdles before being diagnosed and treated properly. The aim of this paper is to: summarize the nocturia patient pathway, explore how nocturia is diagnosed and treated in the real world and use the Delphi method to develop a practical algorithm with a focus on what steps need to be taken before prescribing desmopressin.

METHODS

Evidence comes from existing guidelines (Google, PubMed), International Consultation on Incontinence-Research Society (ICI-RS) 2017, prescribing information and a Delphi panel (3 rounds). The International Continence Society initiated this study, the authors represent the ICI-RS, European Association of Urology, and Society of Urodynamics, Female Pelvic Medicine and Urogenital Reconstruction (SUFU).

RESULTS

Diagnostic packages: consensus on, history taking for all causalities, intake diary (fluid, food) and bladder diary, not for its duration. Pelvic (women) or rectal (men) examination, prostate-specific antigen, serum sodium check (SSC), renal function, endocrine screening: when judged necessary. Timing or empty stomach when SSC is not important. Therapeutic packages: the safe candidates for desmopressin can be phenotyped as no polydipsia, heart/kidney failure, severe leg edema or obstructive sleep apnea syndrome. Lifestyle interventions may be useful. Initiating desmopressin: risk management consensus on three clinical pictures. Follow-up of desmopressin therapy: there was consensus on SSC day 3 to 7, and at 1 month. Stop therapy if SSC is <130 mmol/L regardless of symptoms. Stop if SSC is 130 to 135 mmol/L with symptoms of hyponatremia.

CONCLUSION

A summary of the nocturia patient pathway across different medical specialists is useful in the visualization and phenotyping of patients for diagnosis and therapy. By summarizing basic knowledge of desmopressin, we aim to ease its initiation and shorten the patient journey for nocturia.

Er Shen Wan extract alleviates polyuria and regulates AQP 2 and AVPR 2 in a rat model of spleen-kidney Yang deficiency-induced diarrhea

ETHNOPHARMACOLOGICAL RELEVANCE

Er Shen Wan (ESW), has been empirically used for treating spleen-kidney Yang deficiency (SKYD) syndrome in Traditional Chinese medicine (TCM) for centuries and shows a variety of activities. The medicinal formula is a mixture of two component herbs, Psoraleae Fructus (PF, Bu-Gu-Zhi in Chinese) and Myristicae Semen (MS, Rou-Dou-Kou in Chinese). The current study was designed to evaluate ESWP antidiuretic treatment of polyuria and to explore potential mechanisms of renal water metabolism in the rat model of SKYD-induced diarrhea.

MATERIALS AND METHODS

An animal model of 'SKYD-induced diarrhea syndrome' has been established to evaluate the therapeutic effect and action mechanism according to the clinical syndrome and symptoms. The optimal dose (3.5 g/kg) of ESWP was given to rats by gavage for two weeks. Urinary volumes after 24 h were recorded. After the end of the trial, macroscopic morphological and histological examination of the kidney were conducted. Serum levels of Arginine vasopressin (AVP) and aldosterone (ALD) were also measured. Additionally, quantitative real-time RT-PCR (RT-qPCR) and immunohistochemistry (IHC) analyses were performed to clarify the regulation of aquaporin 2 (AQP 2) and arginine vasopressin type 2 receptor (AVPR 2) in the kidney at the gene and tissue expression levels respectively.

RESULTS

After the administration of ESWP, urinary output volume after 24 h was found to be significantly decreased in rats. Elevated plasma levels of AVP and ALD were detected. Histological kidney damage appeared to be impeded, and histological disease scores were reduced. In addition, the expression levels of AQP 2 and AVPR 2 were significantly increased.

CONCLUSION

This study suggests that ESWP may elicit significant effects on the treatment of polyuria. Potential mechanisms at least partially involve hormone regulation, and alleviating renal pathological damage. Simultaneously, ESWP may alter renal water absorption by increasing AQP 2 and AVPR 2 expression levels. Thus, the in vivo experimental evidence indicates that ESWP has a therapeutic effect on the SKYD syndrome, which is consistent with its traditional usage.

Effect of Acupuncture Therapy on Plasma Antidiuretic Hormone, Melatonin and Total Antioxidant Capacity Levels in Patients with Nocturia

Nocturia is a common symptom which causes sleeping disorders in the elderly. A number of studies have demonstrated that acupuncture may modulate a wide range of neuro endocrinological factors following stimulation of acupoints. We aim to examine the effect of acupuncture treatment and plasma levels of ADH, melatonin hormone and total antioxidant capacity (TAC) on nocturia patients. 28 healthy women subjects (Group I) and 27 women nocturia patients (Group II) have been joined to our study. Following a total of 10 acupuncture sessions has been applied with two sessions per week, we took blood samples from the nocturia patients (Group III). Plasma antidiuretic hormone, melatonin and TAC levels were studied by Elisa method. As a result, all of the patients responded to acupuncture treatment positively. In our study, patients with nocturnal polyuria (Group II) showed significantly low plasma antidiuretic hormone and melatonin levels in comparison to the Group I(p<0.001). Although plasma melatonin levels showed an increase by 12.35% in Group III in comparison to Group II, plasma ADH levels did not change between the two groups. Thus, it was concluded that melatonin could be beneficial for nocturia via central nervous system effect. Patients with nocturnal polyuria (Group II) plasma TAC level showed a decrease when compared with the control group (Group I). However, the plasma TAC level decreased by 9.83% following the 10th session in Group III in comparison to Group II (p=0,044). Based on our results we concluded that acupuncture treatment has a regulatory effect on plasma melatonin levels in patients with nocturia and can be used in the treatment of nocturia patients.

The effect of antidiuretic hormone on urine and serum electrolyte levelsin children with primary monosymptomatic nocturnal enuresis

Background/aim: The data concerning the effects of desmopressin on water/electrolyte disturbances of children with primary monosymptomatic nocturnal enuresis (PMNE) are limited. In the present study we aimed to evaluate the effect and tolerability of desmopressin on blood and urine electrolytes and osmolality in PMNE.Materials and methods: Thirty-five children with PMNE between the ages of 5 and 15 participated in the study. Patients collected urine during the daytime and acknowledged the night time fluid restriction before starting to use the desmopressin tablets. The medication was taken orally at least 1 h before bedtime. Blood and urine samples were collected before the introduction of the treatment (day 0) and on the third and seventh days of the administration of desmopressin to determine osmolality and electrolyte levels.Results: Thirty-five patients participated in the study. Twenty-one patients (60%) were male and 14 (40%) were female. The mean age was 9.6 - 2.7 years. There were no significant changes in serum osmolality, urine osmolality, and serum sodium concentration. Mean urine calcium/creatinine ratio was 0.03 - 0.01 mg/mg at the beginning, 0.06 - 0.02 mg/mg on the third day, and 0.04 - 0.01 mg/mg on the seventh day of the study. No significant changes were seen in urine calcium/creatinine ratio before and after treatment.Conclusion: Desmopressin appeared to be a well-tolerated drug and provided a safe and effective treatment for children who were following fluid intake restriction for PMNE.

Can we define and characterize the aging lower urinary tract?-ICI-RS 2015

The prevalence of lower urinary tract (LUT) symptoms increases with age but the etiology is unknown. This article aims to identify research directions that clarify the basis of this association. The initial question is whether biological age is the variable of interest or a time-dependent accumulation of factors that impact on LUT function at rates that differ between individuals. In particular, the accumulation of conditions or agents due to inflammatory states or tissue ischemia is important. Much of the above has been concerned with changes to bladder function and morphology. However, the outflow tract function is also affected, in particular changes to the function of external sphincter skeletal muscle and associated sacral motor nerve control. Nocturia is a cardinal symptom of LUT dysfunction and is more prevalent with aging. Urine production is determined by diurnal changes to the production of certain hormones as well as arterial blood pressure and such diurnal rhythms are blunted in subjects with nocturia, but the causal links remain to be elucidated. Changes to the central nervous control of LUT function with age are also increasingly recognized, whether in mid-brain/brainstem regions that directly affect LUT function or in higher centers that determine psycho-social and emotional factors impinging on the LUT. In particular, the linkage between increasing white matter hyperintensities and LUT dysfunction during aging is recognized but not understood. Overall, a more rational approach is being developed to link LUT dysfunction with factors that accumulate with age, however, the precise causal pathways remain to be characterized. Neurourol. Urodynam. 36:854-858, 2017. © 2017 Wiley Periodicals, Inc.

Pitfalls and opportunities in multidisciplinary research about nocturia in adults

OBJECTIVES

Describe current shortcomings in clinical research on the treatment of nocturia in adults, and suggest new directions for future studies in this field.

METHODS

A literature search was conducted using the keywords 'nocturia,' 'nocturnal polyuria,' 'sleep,' and 'hypertension.'

RESULTS

Nocturia, or waking up at night to void, is a highly prevalent and bothersome lower urinary tract symptom (LUTS) affecting up to 40% of adults. Since the majority of patients are diagnosed with nocturnal polyuria (NP) as one of the underlying causes, it is not surprising that the effect of treatments for overactive bladder (OAB) and bladder outlet obstruction (BOO) are disappointing with regard to nocturia. Therefore, we suggest to conduct studies in which nocturic patients are treated according to the underlying pathophysiology: (1) antimuscarinics or β3-agonists for OAB symptoms, (2) α-blockers or 5α-reductase inhibitors in men with BOO caused by enlarged prostates, (3) desmopressin or diuretics for NP, (4) continuous positive airway pressure in nocturic patients with obstructive sleep apnea, and (5) all its combinations in case of combined pathophysiology. Not only the effect on treatment efficacy or side effects needs to be assessed, but also the impact on related comorbidities such as sleep disorders, hypertension, and endocrine functions such as blood glucose regulation.

CONCLUSION

Future research needs to subtype nocturic patients in order to adapt treatment according to the underlying cause.

Lower urinary tract symptoms and metabolic disorders: ICI-RS 2014

AIMS

To investigate the link between lower urinary tract symptoms (LUTS) and metabolic disorders.

MATERIALS AND METHODS

This report results from presentations and subsequent discussions about LUTS and metabolic disorders at the International Consultation on Incontinence Research Society (ICI-RS) in Bristol, 2014.

RESULTS

There are common pathophysiological determinants for the onset of LUTS and the metabolic syndrome (MetS). Both conditions are multifactorial, related to disorders in circadian rhythms and share common risk factors. As in men with erectile dysfunction, these potentially modifiable lifestyle factors may be novel targets to prevent and treat LUTS. The link between LUTS and metabolic disorders is discussed by using sleep, urine production and bladder function as underlying mechanisms that need to be further explored during future research.

CONCLUSION

Recent findings indicate a bidirectional relationship between LUTS and the MetS. Future research has to explore underlying mechanisms to explain this relationship, in order to develop new preventive and therapeutic recommendations, such as weight loss and increasing physical activity. The second stage is to determine the effect of these new treatment approaches on the severity of LUTS and each of the components of the MetS.

Circadian disruption: New clinical perspective of disease pathology and basis for chronotherapeutic intervention

Biological processes are organized in time as innate rhythms defined by the period (τ), phase (peak [Φ] and trough time), amplitude (A, peak-trough difference) and mean level. The human time structure in its entirety is comprised of ultradian (τ < 20 h), circadian (20 h > τ < 28 h) and infradian (τ > 28 h) bioperiodicities. The circadian time structure (CTS) of human beings, which is more complicated than in lower animals, is orchestrated and staged by a brain central multioscillator system that includes a prominent pacemaker - the suprachiasmatic nuclei of the hypothalamus. Additional pacemaker activities are provided by the pineal hormone melatonin, which circulates during the nighttime, and the left and right cerebral cortices. Under ordinary circumstances this system coordinates the τ and Φ of rhythms driven by subservient peripheral cell, tissue and organ clock networks. Cyclic environmental, feeding and social time cues synchronize the endogenous 24 h clocks and rhythms. Accordingly, processes and functions of the internal environment are integrated in time for maximum biological efficiency, and they are also organized and synchronized in time to the external environment to ensure optimal performance and response to challenge. Artificial light at night (ALAN) exposure can alter the CTS as can night work, which, like rapid transmeridian displacement by air travel, necessitates realignment of the Φ of the multitude of 24 h rhythms. In 2001, Stevens and Rea coined the phrase "circadian disruption" (CD) to label the CTS misalignment induced by ALAN and shift work (SW) as a potential pathologic mechanism of the increased risk for cancer and other medical conditions. Current concerns relating to the effects of ALAN exposure on the CTS motivated us to renew our long-standing interest in the possible role of CD in the etiopathology of common human diseases and patient care. A surprisingly large number of medical conditions involve CD: adrenal insufficiency; nocturia; sleep-time non-dipping and rising blood pressure 24 h patterns (nocturnal hypertension); delayed sleep phase syndrome, non-24 h sleep/wake disorder; recurrent hypersomnia; SW intolerance; delirium; peptic ulcer disease; kidney failure; depression; mania; bipolar disorder; Parkinson's disease; Smith-Magenis syndrome; fatal familial insomnia syndrome; autism spectrum disorder; asthma; byssinosis; cancers; hand, foot and mouth disease; post-operative state; and ICU outcome. Poorly conceived medical interventions, for example nighttime dosing of synthetic corticosteroids and certain β-antagonists and cyclic nocturnal enteral or parenteral nutrition, plus lifestyle habits, including atypical eating times and chronic alcohol consumption, also can be causal of CD. Just as surprisingly are the many proven chronotherapeutic strategies available today to manage the CD of several of these medical conditions. In clinical medicine, CD seems to be a common, yet mostly unrecognized, pathologic mechanism of human disease as are the many effective chronotherapeutic interventions to remedy it.

Nocturia, Insomnia Symptoms and Mortality among Older Men: The Health, Aging and Body Composition Study

STUDY OBJECTIVES

To examine the association between nocturia (walking up from sleep for urination) and mortality risk among community dwelling older men.

METHODS

This is a secondary data analysis using data obtained from the Health Aging Body Composition (Health ABC) study. Frequency of nocturia was determined at baseline using a questionnaire.

RESULTS

A total of 1,478 older men, mean (SD) age 73.8 (2.9) years, were included in the analysis. During a follow up period of 9.9 years, a total of 760 deaths were reported. Mortality rate was significantly higher for participants with 3 or more nocturia episodes per night, in comparison to those with 0-1 episodes (HR [CI] : 1.21 [1.00-1.47], p = 0.055), even after controlling for baseline characteristics which included demographic variables, body mass index, lower urinary tract symptoms, use of loop diuretics, insomnia symptoms, feeling excessively sleepy during the day/daytime naps, sleep duration, and use of sleep medications. However, the association between ≥ 3 nocturia episodes per night and mortality risk was no longer statistically significant once prevalent diabetes mellitus and cardiovascular disease were included in the model (HR [CI]: 1.18 [0.97- 1.44], p = 0.100).

CONCLUSIONS

Nocturia is associated with mortality independent of insomnia symptoms and sleep duration. The relationship is explained in part by prevalent cardiovascular disease and diabetes mellitus. The results underscore the impact of these medical conditions on the association between 3 or more nocturia episodes and increased mortality risk among older men.

Microvascular Complications and Prevalence of Nocturia in Japanese Patients With Type 2 Diabetes Mellitus: The Dogo Study

OBJECTIVE

To evaluate the association between microvascular complications and nocturia among Japanese patients with type 2 diabetes mellitus.

METHODS

Study subjects were 731 Japanese patients with type 2 diabetes mellitus. A self-administered questionnaire was used to collect information on the variables under study. Study subjects were considered to have nocturia if they answered "once or more" to the question: "How many times do you typically wake up to urinate from sleeping at night until waking in the morning?" Diabetic neuropathy was diagnosed if the patients showed two or more of the following three characteristics: neuropathic symptoms, the absence of the Achilles reflex, or abnormal vibration perception. Diabetic nephropathy was defined as positive when the estimated glomerular filtration rate was <30 mL/min/1.73 m(2) and/or the urine albumin-to-creatinine ratio was ≥34 mg/mmol creatinine. Several ophthalmology specialists were responsible for evaluating diabetic retinopathy. Adjustment was made for sex, age, body mass index, duration of diabetes mellitus, current smoking, current drinking, hypertension, stroke, ischemic heart disease, and glycated hemoglobin.

RESULTS

The prevalence of nocturia was 80.4%. Diabetic retinopathy was independently positively associated with nocturia (adjusted odds ratio 2.39 [95% confidence interval: 1.08-6.11]). In contrast, diabetic nephropathy or diabetic neuropathy was not associated with nocturia.

CONCLUSION

In Japanese patients with type 2 diabetes mellitus, only diabetic retinopathy was independently positively associated with nocturia.

Management of nocturia in the female

Nocturia is a common but overlooked lower urinary tract symptom that substantially reduces patient health and quality of life. Though traditionally viewed as occurring predominantly in males, nocturia has been found to be equally as prevalent in females. The recent emphasis on the importance of nocturia has resulted in a surge of research studies, providing a foundation for current and future management decisions. In this review, we describe the current recommendations for the female patient in light of the most recently published studies, including a unique interest in predicting treatment response.

Exploring nocturia: gender, age, and causes

PURPOSE

This study aims to clarify differences in parameters based on frequency volume chart (FVC) and on daytime and nighttime urine according to the nocturia frequency, age, and gender.

MATERIALS AND METHODS

This observational study was executed between 2011 and 2013. Participants (>18 years, ≤65 years) with or without nocturia (controls) were included and completed a 72 hr FVC; osmolality and sodium excretion were analyzed on daytime and nighttime urine.

RESULTS

(1) Nocturia severity: Compared to controls (N = 38), those with ≥2 nocturia episodes (N = 29) have higher nocturnal voided volume (NVV) (P < 0.001) based on increased sodium excretion (P = 0.003) and lower functional bladder capacity (P < 0.001). Those with one nocturia episode (N = 21) present with lower bladder capacity (P = 0.005). (2) Gender: women with 1 and ≥2 episodes have lower bladder capacity than controls (P = 0.047 and P < 0.001, respectively). Men with ≥2 episodes present with increased NVV (P = 0.001) and decreased bladder capacity (P = 0.049). (3) Age: Younger participants (<44 years) with ≥2 nocturia episodes present with lower functional bladder capacity than controls (P < 0.001). Older participants (45-65 years) present with both increasing NVV and decreasing bladder capacity with increasing nocturia frequency (P < 0.001); sodium excretion is higher in those with ≥2 episodes (P = 0.029). (4) Causes: the percentage of isolated NP decreases (P = 0.005), whereas the combination of both causes increases with increase in number of nocturia episodes (P = 0.020).

CONCLUSIONS

The mismatch between functional bladder capacity and NVV with increasing nocturia frequency demands a comprehensive diagnostic approach to subtype the patient, which involves anamnesis, FVC, and analysis of daytime and nighttime urine.

Gender difference in efficacy and dose response in Japanese patients with nocturia treated with four different doses of desmopressin orally disintegrating tablet in a randomized, placebo-controlled trial

WHAT'S KNOWN ON THE SUBJECT? AND WHAT DOES THE STUDY ADD?: Desmopressin orally disintegrating tablet (ODT) 60-240 μg has proved an effective and well-tolerated antidiuretic treatment in male and female patients with nocturia. The main adverse event is hyponatraemia. Recent studies suggest that female patients are more sensitive to desmopressin ODT, achieving the same efficacy at lower doses than male patients. The study demonstrates the efficacy of desmopressin ODT in male and female Japanese patients with nocturia. It provides further evidence that the optimum desmopressin dose for the treatment of nocturia is lower in females than in males. Tailoring the dose according to gender provides an improved therapeutic window with the benefits of a decreased risk of hyponatraemia without compromising efficacy.

OBJECTIVES

To establish the dose-response efficacy of desmopressin in a Japanese patient population for the treatment of nocturia. To explore gender differences in sensitivity to desmopressin in Japanese patients with nocturia.

PATIENTS AND METHODS

A phase II multicentre, randomized, placebo-controlled, double-blind, parallel-group, comparative clinical trial was conducted. Subjects aged 55-75 years, with a mean of ≥2 voids per night, were included and randomized to receive placebo or one of four doses of desmopressin orally disintegrating tablet (ODT): 10 μg, 25 μg, 50 μg or 100 μg. The dose-response relationship of pharmacodynamic variables measured after a single dose of desmopressin administered to water-loaded subjects (treatment period 1) was compared with the primary clinical endpoint of change from baseline in mean number of nocturnal voids, after 28 days of desmopressin treatment (treatment period 2).

RESULTS

A total of 116 patients were treated in treatment period 1 of whom 113 qualified for treatment period 2, and 111 completed the study. In treatment period 1 a dose-response relationship was observed, both overall and in each gender group. Overall, the duration of antidiuretic action (DOA; time with urine osmolality >200 mOsm/kg) for the 25, 50 and 100 μg doses was 2 h (P = 0.010), 3.45 h (P < 0.001) and 5.74 h (P < 0.001), respectively; all statistically significant compared with placebo. Female patients were found to be more sensitive to desmopressin; DOA in female patients was longer than in male patients after desmopressin 25 and 50 μg. Extrapolation suggests that male patients require ∼58 μg to achieve similar DOA to females receiving 25 μg. A dose-response relationship was also seen in treatment period 2 for the group overall with a greater reduction in mean number of nocturnal voids from baseline to day 28 at higher doses, and with significant reductions in the 25- (P = 0.015) 50- (P < 0.001) and 100-μg (P = 0.001) dose groups compared with placebo. Similar dose-response relationships were also seen when the data were analysed by gender. Desmopressin ODT was well tolerated with no serious or severe adverse events.

CONCLUSIONS

A dose-response relationship for desmopressin ODT was shown in a population of Japanese patients with nocturia. The study suggests that the optimum desmopressin dose for the treatment of nocturia is lower in females than in males, indicating a gender-specific therapeutic window with a decreased risk of hyponatraemia without compromising efficacy on reduction of nocturnal voids. Further dose-finding studies are planned to confirm the recommended dose for the treatment of nocturia in a Japanese patient population.

Causes and mechanisms of nondipping hypertension

Growing evidence indicates that nondippers have worsened cardiovascular outcomes than dippers. Ambulatory blood pressure monitoring with a lack of nocturnal BP fall (nondipping) have also been shown to be more closely associated with target organ damage and worsened cardiovascular outcome than in patients with essential hypertension with dipping pattern. The underlying pathogenetic mechanisms potentially linking nondipping with cardiovascular disease are not fully understood. There are multiple possible underlying pathophysiologic mechanisms in the impaired BP decline during the night. Extrinsic and intrinsic factors including abnormal neurohormonal regulation, lack of physical activity, nutritional factors such as increased dietary sodium intake, and smoking of tobacco have been implicated for blunted circadian rhythm of BP. Certain diseases such as diabetes and chronic renal diseases also affect the circadian BP rhythm. Currently, the clinical importance of nondipping is known well; however, the relationship between certain disease states and nondipping has not been fully explained yet. This paper will attempt to address to clarify the underlying basis for nondipping and the specific associations with various disease states.

Albuminuria assessed from first-morning-void urine samples versus 24-hour urine collections as a predictor of cardiovascular morbidity and mortality

Screening for albuminuria has been advocated because it is associated with cardiovascular morbidity and all-cause mortality. The "gold standard" to assess albuminuria is 24-hour urinary albumin excretion (UAE). Because 24-hour urine collection is cumbersome, guidelines suggest measuring albuminuria in a first morning void, either as urinary albumin concentration (UAC) or adjusted for creatinine concentration, the albumin:creatinine ratio (ACR). To decide which albuminuria measure to use in clinical practice, it is essential to know which best predicts clinical outcome. In a sample representative of the Groningen (the Netherlands) population (n = 3,414), the authors compared UAC, ACR, and UAE as predictors of cardiovascular events and all-cause mortality. During a median follow-up of 7.5 years, which ended December 31, 2005, they observed 278 events (a major adverse cardiovascular event or mortality). The area under the receiver operating characteristic curve predicting events was 0.65 for UAE, 0.62 for UAC (P = 0.06 vs. UAE), and 0.66 for ACR (P = 0.80 vs. UAE; P = 0.01 vs. UAC). When sex-specific subgroups were considered, UAE was superior to UAC in predicting outcome (P = 0.04) for females, whereas, for males as well as females, no difference was found between ACR and UAE. To predict cardiovascular morbidity and all-cause mortality, measuring ACR in a first-morning-void urine sample is a good alternative to measuring 24-hour UAE.

Diuretic pattern in adults with nocturnal polyuria: The possible contribution of blood pressure to the worsening of nocturnal polyuria

AIM

The present study was undertaken to investigate diuresis rate determinants of nocturnal polyuria (NP) in adults.

SUBJECTS AND METHODS

A total of 33 patients aged 50-87 years (mean: 68.6), with nocturnal urine volumes exceeding 10 mL per kg body weight based on records of a frequency-volume chart, were enrolled to evaluate the relationships between diuresis rates and related variables. Multiple regression analyses were conducted to identify diuresis rate determinants, including brain natriuretic peptide. Furthermore, a hypertonic saline infusion test was conducted to examine the arginine vasopressin (AVP) response to plasma osmotic change.

RESULTS

Nocturnal voids correlated negatively with the daytime diuresis rate (P = 0.019). Despite a similar total urine volume per kg body weight (TUV/kgBw), systolic and mean blood pressure (MBP) significantly correlated with the nocturnal diuresis rate positively and the daytime diuresis rate negatively. The MBP, which was selected as a representative variable for blood pressure, was found to be an independent determinant for the nocturnal. The MBP and TUV/kgBw were independent determinants for the daytime diuresis rate on multiple regression analyses. Neither age, AVP, nor brain natriuretic peptide were determinants for them. When divided into two groups using their median nocturnal diuresis rates (0.023 mL/kg/min), there was no difference in the prevalence of stroke and the taking of hypnotics between the groups. Overall, a hypervolemic condition or increased sympathetic nerve activity in NP was suggested using the hypertonic saline infusion test.

CONCLUSIONS

These results indicate that blood pressure might play an important role as a determinant of increasing nocturnal diuresis in NP.