Canadian Urological Association best practice report: Diagnosis and management of nocturia

Question 1

What is the primary aim of the best practice report on the diagnosis and management of nocturia by the Canadian Urological Association?

Answer 1

The primary aim is to provide healthcare providers with background information and a practical, evidence-based algorithmic approach to the evaluation and management of patients with nocturia.

Question 2

Why do patients with nocturia benefit from a multimodal and multidisciplinary approach?

Answer 2

Patients with nocturia benefit from a multimodal and multidisciplinary approach due to the multifactorial etiology of nocturia. It allows for the treatment of underlying diseases or conditions that may be contributing to symptoms, and targeted management to improve symptoms.

Question 3

What are the main databases used to gather information for the review on the diagnosis and management of nocturia?

Answer 3

The main databases used were PubMed, Medline, and the Cochrane Library database. Bibliographies of relevant articles were also reviewed.

Question 4

How was the quality of evidence evaluated in the review of the diagnosis and management of nocturia?

Answer 4

The quality of evidence was evaluated using the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) framework.

Question 5

How were recommendations for the diagnosis and management of nocturia developed in the absence of high-quality evidence?

Answer 5

The strength of recommendations was supported by clinical principles, fundamental pathophysiology, and consensus expert opinion.

Question 6

Figure 1. Prevalence of nocturia (A) one or more times per night; and (B) two or
more times per night in Canadian adults, by age and sex.9

Question 7

What is the definition of nocturia according to the International Continence Society (ICS)?

Answer 7

Nocturia is defined as waking one or more times to void during the hours of sleep, with each void preceded and followed by sleep.

Question 8

Although voiding even once at night is considered nocturia, what does some literature suggest about the number of voids per night?

Answer 8

Some literature suggests that fewer than two voids per night does not result in significant patient bother.

Question 9

What can influence the degree of bother experienced by individual patients from nocturia?

Answer 9

The degree of bother experienced by individual patients can vary according to factors beyond just the number of voids per night.

Question 10

What are the potential consequences of nocturia?

Answer 10

Nocturia is associated with impaired quality of life and even mortality. The association with mortality is independent of bother.

Question 11

When should patients be assessed for nocturia?

Answer 11

Patients should be assessed for nocturia even if they don’t independently report it, as bother often motivates patients to raise nocturia as an issue with their care providers.

Question 12

How does the prevalence of nocturia vary with age in Canada?

Answer 12

Nocturia by any definition increases with age, particularly in men. From a Canadian survey, prevalence using the ICS definition of one or more episodes per night was estimated to be 36.4% in all adults and 49.5% in adults over age 65. When defined as two or more episodes per night, prevalence was 9.1% in all adults and 23.8% in adults over the age of 65.

Question 13

What is the role of Arginine vasopressin (AVP, or antidiuretic hormone [ADH]) in nocturnal urine production?

Answer 13

AVP is released from the posterior pituitary and serves as the primary hormone regulating renal water excretion. Factors such as high serum osmolality, hypovolemia, and angiotensin II stimulate AVP, leading to water reabsorption, whereas factors such as atrial natriuretic peptide (ANP/ANH), prostaglandin E2 (PGE2), and hypercalcemia inhibit AVP, leading to diuresis.

Question 14

How does aging affect the circadian rhythm of hormone release?

Answer 14

With aging, the circadian rhythm of release of these hormones is blunted, which can increase nocturnal urine production.

Question 15

What are the key components required for normal bladder function?

Answer 15

Normal bladder function requires adequate bladder storage and emptying abilities. This requires coordination of multiple components, including the central and peripheral nervous systems, detrusor smooth muscle function, and urethral and pelvic floor function. The bladder urothelium also seems to have a role in regulating urinary function and possibly contributing to AVP-mediated water homeostasis.

Question 16

What considerations should be made for the general patient population regarding bladder function?

Answer 16

Important considerations for the general patient population are that bladder capacity may diminish with age, and nocturnal detrusor overactivity may occur in patients with underlying overactive bladder (OAB).

Question 17

Figure 2. Initial workup of patients presenting with nocturia.

Question 18

What is the recommended approach for patients presenting with nocturia?

Answer 18

Patients presenting with nocturia should be counselled on the multifactorial mechanisms contributing to nocturia. Clinicians should consider the symptom in the context of the patient’s comorbidities, dietary, lifestyle, and voiding behaviors.

Question 19

What factors should be evaluated when diagnosing nocturia?

Answer 19

Patients should be evaluated for their fluid consumption habits, lower urinary tract symptoms, sleep habits, medication usage, symptoms of obstructive sleep apnea, cardiovascular conditions, diabetes, any prior lower urinary tract or pelvic surgeries, and pain.

Question 20

What indirect symptoms may indicate nocturia or obstructive sleep apnea?

Answer 20

Insomnia and daytime tiredness can be indirect symptoms of nocturia or obstructive sleep apnea.

Question 21

How can undiagnosed obstructive sleep apnea be screened and confirmed?

Answer 21

Undiagnosed obstructive sleep apnea can be screened using the STOP-Bang questionnaire and confirmed with in-laboratory polysomnography, which is considered the gold-standard diagnostic tool.

Question 22

What role can medications play in contributing to nocturia?

Answer 22

Certain medications can contribute to nocturia by increasing diuresis, changing vesico-sphincteric function, increasing water retention and peripheral edema, or interfering with sleep.

Question 23

What types of medications may affect nocturia and what are their associated mechanisms?

Answer 23

Diuretics, ACE inhibitors, and lithium can increase diuresis. Acetylcholinesterase inhibitors can change vesico-sphincteric function. Calcium channel blockers and steroids can increase water retention and peripheral edema. CNS stimulants, psychotropics, antiepileptics, and decongestants can interfere with sleep.

Question 24

What are some urological causes of nocturia that result in diminished global or nocturnal bladder capacity?

Answer 24

Overactive bladder, benign prostatic hyperplasia, ureteral or bladder calculi, learned voiding dysfunction, neurogenic voiding dysfunction, nocturnal detrusor overactivity.

Question 25

What urological condition can cause nocturia due to an overactive bladder?

Answer 25

Overactive bladder.

Question 26

Which urological cause of nocturia is associated with an enlarged prostate?

Answer 26

Benign prostatic hyperplasia.

Question 27

What urological condition can cause nocturia due to learned voiding dysfunction?

Answer 27

Learned voiding dysfunction.

Question 28

What are some non-urological causes of nocturia that result in global or nocturnal polyuria, or sleep disruption?

Answer 28

Heart failure, peripheral edema, uncontrolled or poorly controlled diabetes mellitus, diabetes insipidus, primary polydipsia, obstructive sleep apnea, medication effects, chronic pain, neurologic disorders, nocturnal polyuria.

Question 29

What non-urological condition that can cause nocturia is associated with excessive thirst and high intake of fluids?

Answer 29

Primary polydipsia.

Question 30

Which non-urological cause of nocturia is associated with a blockage in the airflow during sleep?

Answer 30

Obstructive sleep apnea.

Question 31

Which non-urological cause of nocturia is associated with nerve-related issues?

Answer 31

Neurologic disorders.

Question 32

What drugs can cause diuresis, either via increased free water or osmotic clearance, and potentially contribute to nocturia?

Answer 32

Diuretics, progesterone, melatonin, ACE inhibitors, lithium, and SGLT-2 inhibitors.

Question 33

What drugs can cause antidiuresis, either via decreased free water or osmotic clearance, and potentially contribute to nocturia?

Answer 33

ddAVP, testosterone, estrogens, antipsychotics, chemotherapeutics, antidepressants, antiepileptics, opiates, calcium channel blockers, beta adrenoreceptor antagonists, NSAIDs, lithium, melatonin, corticosteroids, thiazolidinediones.

Question 34

What drugs can cause edema and potentially contribute to nocturia?

Answer 34

Caffeine, alcohol, anticholinesterase inhibitors, cyclophosphamide, and ketamine.

Question 35

What drugs can have central nervous system effects (e.g., insomnia) and potentially contribute to nocturia?

Answer 35

Antiepileptics, psychotropic agents, stimulants, antihypertensives (alpha- and beta-blockers), decongestants, hormones (corticosteroids, thyroid hormones), caffeine.

Question 36

What drugs can precipitate lower urinary tract symptoms and potentially contribute to nocturia?

Answer 36

Caffeine, alcohol, anticholinesterase inhibitors, cyclophosphamide, ketamine.

Question 37

What is the definition of the 24-hour urine volume in the context of diagnosing nocturia?

Answer 37

The 24-hour urine volume refers to the total volume voided over 24 hours. A 24-hour urine volume greater than 40 ml/kg is diagnostic of global polyuria.

Question 38

What are the clinical implications of a low Maximum Voided Volume (MVV)?

Answer 38

A low MVV indicates reduced global bladder capacity.

Question 39

How is the Nocturia Index (Ni) calculated and what does a Ni greater than 1 suggest?

Answer 39

The Nocturia Index (Ni) is calculated by dividing the Nocturnal Urine Volume (NUV) by the Maximum Voided Volume (MVV). A Ni greater than 1 suggests nocturia due to a mismatch between production and capacity during sleep.

Question 40

How is the Nocturnal Bladder Capacity Index (NBCi) calculated and what does an NBCi greater than 0 indicate?

Answer 40

The Nocturnal Bladder Capacity Index (NBCi) is calculated by subtracting the Predicted Number of Nightly Voids (PNV) from the Actual Number of Nightly Voids (ANV). An NBCi greater than 0 indicates reduced nocturnal bladder capacity.

Question 41

How is the Nocturnal Polyuria Index (NPi) calculated and what does an NPi between 20-33% indicate?

Answer 41

The Nocturnal Polyuria Index (NPi) is calculated by dividing the Nocturnal Urine Volume (NUV) by the 24-hour urine volume. An NPi between 20-33% is diagnostic of Nocturnal Polyuria (NP), but this is age-dependent.

Question 42

Figure 3. Multimodal approach to management of nocturia, organized by disease domains with subsequent pathways for treatment and consideration of specialist referral. Note that nocturia is often multifactorial and requires workup and management across multiple domains to achieve patient treatment goals. Clinical specialties listed are not exhaustive and may vary by region.

Question 43

What are the key components of a thorough consultation for nocturia?

Answer 43

A consultation should include a comprehensive history, including an assessment of urinary symptoms, fluid intake (quantity, type, and timing), medications, and sleep habits. Physical examination should focus on factors such as blood pressure, obesity, large neck circumference, cognitive and motor capacity, bladder distension, digital rectal exam and external genital examination in men, pelvic examination in women, and lower leg edema.

Question 44

What are the recommended disease-specific questionnaires for assessing nocturia severity and treatment progress?

Answer 44

The recommended questionnaires are the International Consultation on Incontinence Questionnaire Nocturia Module, the Nocturia Quality-of-Life questionnaire, the Nocturia Impact Diary, and the TANGO Short-Form.

Question 45

What is the purpose and components of a frequency-volume chart (or voiding diary) in investigating nocturia?

Answer 45

A frequency-volume chart is the most important objective diagnostic tool in nocturia. It helps clarify the underlying pathophysiology by differentiating global or nocturnal polyuria from reduced bladder capacity. Over a 72-hour period, patients must record: 1) time and volume of each voided urine, 2) volume and type of fluid intake, 3) any episodes of incontinence, and 4) sleep and wake-up times.

Question 46

How is the nocturia index (Ni) calculated, and what does it signify?

Answer 46

The nocturia index (Ni) is calculated by dividing the nocturnal urine volume (NUV) by the maximum voided volume (MVV). If this value is >1, nocturia or enuresis will occur because the MVV has been exceeded by NUV.

Question 47

What are the recommended initial tests for patients presenting with nocturia?

Answer 47

All patients should undergo physical examination, a frequency-volume chart, urinalysis, and post-void residual (PVR) urine measurement. Disease-specific questionnaires should be used to ascertain bother and severity. Cystoscopy and urodynamics are not usually necessary for patients with nocturia.

Question 48

What are the specific physical examination points for men and women in the context of nocturia?

Answer 48

For men, attention should be given to conditions such as benign prostatic hyperplasia (BPH), phimosis, and meatal stenosis. For women, the focus should be on vaginal atrophy and pelvic organ prolapse.

Question 49

What is the TANGO Short-Form questionnaire and its purpose?

Answer 49

The TANGO Short-Form (TANGO SF) is a patient-administered screening tool consisting of 22 statements across four domains (cardio/metabolic, sleep, urinary tract, and wellbeing domains). It assists in diagnosing non-lower urinary tract contributing components of nocturia.

Question 50

How should the first morning void be considered in the context of nocturia assessment?

Answer 50

For the purposes of calculations, the first morning void is included in the nocturnal urine volume produced but should not be considered a nocturia event.

Question 51

Which patients with microhematuria should be referred to a urologist?

Answer 51

Patients with microhematuria should be referred to a urologist for assessment as per the Canadian Urology Association (CUA) hematuria guidelines.

Question 52

What additional laboratory investigations should be considered in nocturia?

Answer 52

Additional investigations may include serum electrolytes and creatinine, serum glucose/HbA1c, urinary osmolality, sex hormone levels (LH, FSH, testosterone, estrogen), and plasma B-type natriuretic peptide (BNP) levels.

Question 53

When should cystoscopy and urodynamics be considered in the context of nocturia?

Answer 53

Cystoscopy and urodynamics may be necessary in individual patients to evaluate the exact origin of nocturia in the setting of significant lower urinary tract symptoms (LUTS).

Question 54

How is nocturia classified clinically and what tool is typically used to guide this classification?

Answer 54

Nocturia is classified clinically based on its etiology. This classification helps understand the multifactorial nature of nocturia and directs individualized treatment. An accurately completed 72-hour voiding diary is used to guide the classification into one of the following groups: global polyuria, nocturnal polyuria, reduced bladder capacity, sleep disorders, or mixed disorders.

Question 55

What is global polyuria (GP), and what are its causes?

Answer 55

Global polyuria (GP) is defined as a 24-hour urine output >40 ml/kg. The causes of GP include diabetes mellitus (DM), diabetes insipidus (DI), and primary polydipsia (PPD).

Question 56

How is global polyuria (GP) investigated and managed?

Answer 56

The investigation of GP is first approached by performing an overnight water deprivation test, with restriction of all fluid intake for eight hours or until 5% of body mass has been lost. This is followed by administration of 2 mcg of intramuscular desmopressin and measurement of urine and plasma osmolality. Management of GP depends on a precise determination of its underlying cause and, in many cases, it can be managed by primary care or referred to an internal medicine specialist.

Question 57

What are the steps to diagnose primary polydipsia (PPD)?

Answer 57

If a normal urine osmolality (>600–800 mOsm/kg) is recorded after the overnight water deprivation test and administration of desmopressin, then the diagnosis is PPD. The patient can then be instructed to fluid restrict. PPD may be psychogenic or dipsogenic, often secondary to brain insults (e.g., trauma, surgery, neoplasia, radiation) that impact the osmoregulation of thirst.

Question 58

What are the steps to diagnose diabetes insipidus (DI) and how is it classified?

Answer 58

If the first morning urine osmolality is low (<600 mOsm/kg), then DM should be ruled out by measuring serum glucose and hemoglobin A1C. Abnormally low urine osmolality with normal glucose testing indicates DI. DI is secondary to insufficient synthesis or secretion of ADH (central DI), or abnormal response of the kidneys to circulating ADH (nephrogenic DI). The type of DI is determined by measuring the urine osmolality in response to desmopressin 40 mcg intranasally or 0.4 mg orally (renal concentrating capacity test), which will normalize the urine osmolality in central but not nephrogenic DI.

Question 59

What are the potential causes of central DI and nephrogenic DI?

Answer 59

Central DI may be idiopathic or secondary to trauma, pituitary neoplasms, or vascular, infiltrative, or infectious processes. Nephrogenic DI may be caused by chronic kidney disease, excess prostaglandin or ANP, hypercalcemia, hypokalemia, lithium toxicity, or tetracycline use.

Question 60

What is nocturnal polyuria (NP)?

Answer 60

Nocturnal polyuria (NP) is a condition where urine overproduction occurs only at night.

Question 61

What are the diagnostic criteria for nocturnal polyuria according to the International Continence Society (ICS)?

Answer 61

The ICS defines nocturnal polyuria as a NP index (NPi) >33% in those over 65 years old and NPi >20% in those between 25–65 years old. This means NP occurs when adults aged 25–65 years old produce more than 20% of their total urine volume overnight, or when adults over 65 years old produce more than 33% of their total urine volume overnight.

Question 62

What are other definitions of nocturnal polyuria (NP)?

Answer 62

Other definitions of nocturnal polyuria include nocturnal urine production >90 ml/hr, nocturnal urine volume (NUV) >6.4 ml/kg, and NUV >0.9 ml/min.

Question 63

What are the possible underlying causes for nocturnal polyuria (NP)?

Answer 63

The differential diagnosis for NP includes edema-forming states (e.g., congestive heart failure, nephrotic syndrome), obstructive sleep apnea (OSA), neurodegenerative diseases (e.g., Parkinson’s, Alzheimer’s), chronic kidney disease, autonomic neuropathy, venous stasis, and idiopathic NP, which is thought to be caused by deficient nocturnal ADH secretion.

Question 64

What conditions can cause reduced bladder capacity?

Answer 64

Reduced bladder capacity can be caused by a variety of conditions including bladder outlet obstruction, detrusor underactivity, neurogenic bladder, overactive bladder (OAB) syndrome, cystitis, and bladder pain syndrome. These conditions can affect the time between voids or diminish functional bladder capacity.

Question 65

How does a low Maximum Voided Volume (MVV) relate to bladder capacity?

Answer 65

A low MVV is indicative of overall reduced bladder capacity.

Question 66

What is the Nocturnal Bladder Capacity Index (NBCi) and how is it calculated?

Answer 66

The NBCi is an index that compares actual number of nightly voids (ANV) to the predicted number of nightly voids (PNV). It is calculated by subtracting PNV from ANV.

Question 67

What is the proposed threshold of NBCi that indicates reduced nocturnal bladder capacity contributing to nocturia?

Answer 67

A NBCi >1.3 has been proposed as the threshold indicating that reduced nocturnal bladder capacity contributes to nocturia.

Question 68

Given a patient with a MVV of 400 mL and a NUV of 1000 mL who wakes up four times per night, how would you calculate her NBCi?

Answer 68

Calculate Ni (Nocturia Index) = NUV/MVV = 1000/400 = 2.5
Calculate PNV (Predicted Number of Nightly Voids) = Ni - 1 = 2.5 - 1 = 1.5
Calculate NBCi (Nocturnal Bladder Capacity Index) = ANV (Actual Number of Nightly Voids) - PNV = 4 - 1.5 = 2.5

Question 69

What is the role of sleep disorders in nocturia?

Answer 69

Sleep disorders can potentially drive nocturnal micturition. However, nocturnal voiding in the context of sleep disturbances is typically habitual and done out of convenience rather than need. Patients with suspected sleep disorders can be further evaluated by primary care and/or sleep medicine specialists.

Question 70

What is the nature of the etiology of nocturia?

Answer 70

The etiology of nocturia is often multifactorial. Patients may require subspecialist referrals for the workup of contributing etiologies.

Question 71

What is the recommended approach for clinicians investigating nocturia?

Answer 71

Clinicians investigating nocturia should aim to classify nocturia based on etiology with the guidance of a detailed patient history, physical examination, and frequency-volume chart. Further workup and management of specific causes of nocturia may involve the patient’s primary care practitioner, urologist, other specialists, and allied health professionals as appropriate. This is a strong recommendation with a moderate level of evidence.

Question 72

List some of the behavioral and lifestyle factors that contribute to nocturia.

Answer 72

Numerous factors including increased nocturnal polyuria (NP), sleep disturbances, diminished bladder capacity, high fluid and sodium intake, high protein consumption in the evening, obesity, and lifestyle-related diseases like uncontrolled hypertension.

Question 73

What is a central recommendation for initial management of nocturia?

Answer 73

The provision of guidance on fluid intake and reduction of total daily fluid consumption to 2 L/day or a 25% reduction from baseline.

Question 74

How does sodium intake contribute to nocturia, and what is the recommended action for patients with high salt intake?

Answer 74

Sodium intake correlates with diurnal leg edema and nocturnal urine volume. Patients with high salt intake should reduce their daily sodium consumption to see a beneficial reduction of nocturnal voids.

Question 75

How does obesity contribute to nocturia?

Answer 75

Obesity is an independent risk factor for nocturia as it contributes to Obstructive Sleep Apnea (OSA), which can lead to NP. Obesity also contributes to other chronic disorders and their treatments, which may also contribute to nocturia.

Question 76

What are the general recommendations to manage peripheral edema?

Answer 76

Late afternoon/evening lower limb elevation, use of compression stockings, and diuretics (taken mid-afternoon). These treatments usually lead to a reduction in nighttime voids.

Question 77

How can bladder training be beneficial for patients with nocturia?

Answer 77

Bladder training, especially when used as an adjunct to OAB drugs or other modalities such as biofeedback and/or electrical stimulation, can be effective. Pelvic floor muscle training with biofeedback as part of a behavioral therapy program has proven effective in treating urinary incontinence, and it can also reduce OAB symptoms, including nocturia.

Question 78

What lifestyle-related diseases are associated with an increased risk of NP?

Answer 78

Uncontrolled hypertension is associated with an increased risk of NP. In a Chinese study of 9637 adults, nocturia was associated with cardiovascular disease, hypertension, and Diabetes Mellitus (DM).

Question 79

What are the Canadian Urological Association’s recommendations for the management of nocturia?

Answer 79

Initial treatment should focus on conservative measures directed at behavioral, lifestyle, and dietary modifications. These include total daily and evening fluid restriction, bladder training, weight loss and physical activity, management of peripheral edema, and dietary changes like normal salt intake and decreasing evening protein intake. Counselling on voiding habits and management of coexisting lower urinary tract disorders are optimally performed by urologists.

Question 80

What are the recommendations for managing nocturnal polyuria in patients with nocturia?

Answer 80

The recommendations include:

Evening fluid restriction (none for 2 hours prior to bedtime)
Total daily fluid restriction to 2L/day, or reducing intake by 25% from baseline
Reducing dietary salt intake
Reducing evening protein intake
Restricting or avoiding caffeine and alcohol
Mobilizing peripheral edema fluid through evening leg elevation and the use of support stockings

Question 81

What are the suggested interventions for diminished bladder capacity in patients experiencing nocturia?

Answer 81

Recommended interventions include:

Pre-emptive voiding or clean intermittent catheterization at bedtime
Pelvic floor muscle training
Bladder training

Question 82

How can sleep disturbances, often associated with nocturia, be managed?

Answer 82

Management strategies for sleep disturbances include:

Improving sleep hygiene, such as establishing a relaxing bedtime routine and minimizing electronics before bed
Treating hot flashes in post-menopausal women

Question 83

How should multifactorial causes of nocturia be addressed?

Answer 83

The management of multifactorial causes involves:

Management of chronic lifestyle-related diseases like diabetes, hypertension, and cardiac disease
Weight loss
Increasing exercise and fitness

Question 84

What is the relationship between cardiovascular morbidity and nocturia?

Answer 84

While many authors have drawn an association between cardiovascular morbidity (including diabetes mellitus, increased body mass index, hypertension, cardiovascular disease, and stroke) and nocturia, the causality between the two has not been clearly established. Several cardiorenal conditions can lead to nocturnal polyuria due to alterations in fluid handling by the kidneys, renal function, and associated diuresis.

Question 85

How does hypertension contribute to nocturia?

Answer 85

Hypertension can lead to changes in glomerular filtration and tubular transport, resetting the renal pressure-natriuresis relationship and thus leading to nocturnal polyuria. Repeated arousal from sleep to urinate can further raise blood pressure, creating a vicious cycle.

Question 86

What is the relationship between heart failure and nocturia?

Answer 86

Heart failure can result in atrial stretch and the release of atrial natriuretic peptide (ANP), a hormone that stimulates vasodilation and diuresis through the renin-angiotensin axis. More than 80% of individuals with stable heart failure report one or more nightly episodes of nocturia.

Question 87

How does metabolic syndrome and diabetes contribute to nocturia?

Answer 87

Metabolic syndrome and diabetes, which can contribute to nocturia, are associated with oxidative stress, which results in mitochondrial dysfunction in the kidney and bladder. This mitochondrial dysfunction may affect arginine vasopressin (AVP)-mediated water homeostasis, leading to nocturia.

Question 88

What is the impact of chronic kidney disease on nocturia?

Answer 88

Chronic kidney disease prevents the expected decline in blood pressure during sleep, blunting nocturnal blood pressure dipping. This can predispose patients to nocturia, resulting in enhanced natriuresis and related osmotic diuresis during the night, causing nocturnal polyuria.

Question 89

Which medications are associated with an increased risk of nocturnal polyuria?

Answer 89

Several drugs can alter the renal handling of fluid and are associated with an increased risk of nocturnal polyuria, including calcium channel blockers, lithium, and diuretics. Other medications like antidepressants, certain antihypertensives, antivirals, hormonal therapies, non-steroidal anti-inflammatory drugs (NSAIDs), and some chemotherapeutics and immunologic agents, can cause peripheral edema, which can result in postural diuresis.

Question 90

How can beta-blockers affect nocturia?

Answer 90

Beta-blockers can decrease bladder capacity, which may contribute to the occurrence of nocturia.

Question 91

What is the significance of nocturia as a marker in men?

Answer 91

Nocturia has been found to be a marker for an increased risk of chronic heart diseases in younger men in later life, as well as death in older men.

Question 92

What are some common causes for reduced global and nocturnal bladder capacity that are modifiable?

Answer 92

Common causes include bladder outlet obstruction, involuntary detrusor contractions (OAB and NLUTD), dysfunctional voiding, cystitis, urolithiasis, and lower urinary tract malignancies. Addressing these conditions has the potential to increase bladder capacity.

Question 93

What are the recommended treatments for men with bladder outlet obstruction due to prostate enlargement and nocturia?

Answer 93

The treatments include monotherapy with an alpha-1-blocker or 5-alpha-reductase inhibitor, combination therapy with both, or NSAIDs. However, the clinical improvement from these treatments is usually modest, and long-term use of NSAIDs is not recommended due to potential serious adverse effects.

Question 94

What is the impact of surgical procedures like TURP on nocturia, and what are the predictors of persistent nocturia post-surgery?

Answer 94

TURP can improve nocturia by decreasing PVR, reducing detrusor overactivity, and modulating sensory afferents in the bladder neck and prostatic urethra. However, the improvements are typically modest. Predictors of persistent nocturia after TURP include pre-existing sleep disorders, increased prostate size, metabolic syndrome, and smoking.

Question 95

What is the efficacy of antimuscarinic agents and mirabegron in managing nocturia?

Answer 95

Most antimuscarinics, except Trospium chloride, show no benefit over placebo. Fesoterodine can reduce nocturnal voids and improve sleep quality in patients without NP. Mirabegron significantly reduces mean nocturnal voids and has been shown to be effective when used as an add-on to antimuscarinic monotherapy.

Question 96

What effect does Intradetrusor onabotulinumtoxinA have on nocturia in patients with OAB?

Answer 96

It has only a modest effect, reducing mean nocturnal voids by 0.25 compared to placebo.

Question 97

How should patients presenting with nocturia as part of multiple LUTS be evaluated and treated?

Answer 97

They should be evaluated and treated appropriately for lower urinary tract disorders such as OAB, bladder outlet obstruction, and NLUTD.

Question 98

What is Obstructive Sleep Apnea (OSA), and how might it affect sleep quality and daytime symptoms?

Answer 98

OSA is a condition involving repetitive upper airway closure during sleep, either completely (apnea) or partially (hypopnea). This commonly leads to poor sleep quality, nocturnal hypoxemia, and daytime symptoms such as fatigue and nocturia.

Question 99

How does the sensitivity of nocturia as a predictor of OSA compare to that of snoring?

Answer 99

A retrospective review found that the sensitivity of nocturia as a predictor of OSA is comparable to that of snoring (84.4% vs. 82.6%). The combination of nocturia and snoring demonstrated a sensitivity of 97.4% as a predictive factor for OSA.

Question 100

What is one physiological basis for the association between OSA and nocturia?

Answer 100

During an apneic event, respiratory muscles produce a Müller’s maneuver, creating negative intrathoracic pressure that stretches the atria and ventricles. This leads to the increased release of atrial and brain natriuretic peptides, inhibiting the secretion of ADH and potentially leading to nocturia.

Question 101

What is another mechanism associating OSA with nocturia involving the effect of intermittent hypoxia on the bladder?

Answer 101

Intermittent hypoxia can lead to detrusor instability, bladder non-compliance, and increased spontaneous contractions, potentially leading to nocturia. This is thought to be related to oxidative stress caused by tissue hypoxia.

Question 102

What is the STOPBang questionnaire and what does it screen for?

Answer 102

The STOPBang questionnaire is a commonly used screening tool for OSA. It consists of eight simple questions that can be easily performed in a clinical setting.

Question 103

How is OSA typically confirmed and what is the most effective treatment?

Answer 103

OSA is typically confirmed through polysomnography, performed either as a level 1 sleep study in a specialized testing center or as a level 3 study at home where level 1 polysomnography is unavailable. The most effective treatment for OSA is continuous positive airway pressure (CPAP) therapy.

Question 104

How does treatment of OSA affect nocturia according to research?

Answer 104

Research suggests that treatment of OSA with CPAP can lead to significant improvement in nocturia. A systemic review found that CPAP led to a significant decrease in the frequency of nocturia and urine volume.

Question 105

What is the recommendation regarding screening patients with nocturia for OSA?

Answer 105

The recommendation is that patients with nocturia should be screened for OSA, and the need for further evaluation, management, or specialist referral can be determined by the primary care provider.

Question 106

What is the primary purpose of a bed according to good sleep hygiene?

Answer 106

The bed should be used only for sleep and sexual activities. If sleep is not possible, one should leave the bed and do other relaxing activities before attempting to sleep again.

Question 107

What measures can be taken to prioritize the quality of sleep?

Answer 107

Going to bed and getting up at the same time every day.
Ensuring a restful environment, which includes a comfortable bed in a cool, well-ventilated room, and protection from light and noise.

Question 108

What are some bedtime “rituals” that can facilitate a good night’s sleep?

Answer 108

Preparing for sleep with 20-30 minutes of relaxation activities, such as listening to soft music, meditating, practicing breathing exercises, or doing yoga.
Taking a warm bath.
Having a light snack, which could include warm milk, foods high in tryptophan like bananas, and carbohydrates, which can help induce sleep.

Question 109

What behaviors should generally be avoided for good sleep hygiene?

Answer 109

Napping, especially after 3:00 p.m.
Going to sleep too early in the evening, as this can lead to phase advance syndrome.

Question 110

What should be avoided before bedtime or late in the day for better sleep?

Answer 110

Heavy eating.
Consumption of caffeine or alcohol.
Smoking (as nicotine interferes with sleep).
Exercise, which is a stimulant (though daytime activity will promote later sleep).

Question 111

What mental activities should be avoided while trying to fall asleep?

Answer 111

Thinking about life issues.
Problem-solving.
Rehashing the events of the day.

Question 112

What is Desmopressin (DDAVP™) and how does it work in the management of nocturia?

Answer 112

Desmopressin is a synthetic form of AVP (Arginine Vasopressin), with a duration of action of approximately 6–14 hours. It works by binding the vasopressin type 2 receptor in the distal tubule of the nephron, which increases the activation of aquaporin channels. This leads to the reabsorption of water and a reduction in urine volume.

Question 113

What are the effects of Desmopressin on nocturia in women and men?

Answer 113

Desmopressin significantly reduces nocturnal voids (on average 0.5 fewer voids/night compared to placebo) and increases the duration of the first period of sleep by about one hour in women. The effects are similar in men and its efficacy is likely comparable to alpha-blockers in reducing episodes of nocturia.

Question 114

What is the recommended starting dose of Desmopressin?

Answer 114

The recommended starting dose of Desmopressin is 50–100 mcg taken orally one hour before bedtime, which can be titrated to 200 mcg as desired.

Question 115

What are the potential side effects of Desmopressin?

Answer 115

Potential side effects of Desmopressin include nausea, diarrhea, dizziness, hypertension, and hyponatremia. It should be used with caution in patients with severe liver disease, heart failure, and renal failure.

Question 116

What is the main side effect of concern with Desmopressin and who is at risk?

Answer 116

The primary side effect of concern with Desmopressin is hyponatremia, which can be fatal when severe. Risk factors for clinically significant hyponatremia include increased age (significantly higher after age 65), renal dysfunction, small body mass, female sex, and baseline low-normal sodium levels.

Question 117

What is the proposed monitoring strategy for hyponatremia when a patient is on Desmopressin?

Answer 117

A conservative approach to hyponatremia monitoring involves measuring serum sodium levels at baseline, then at follow-up after one week, one month, and then every six months. This can be tailored to the patient’s individual risk. If the Desmopressin dose is changed, hyponatremia monitoring should be restarted.

Question 118

Apart from Desmopressin, what are two other less studied treatment options for nocturia?

Answer 118

Diuretics (such as furosemide) can be given six hours prior to bedtime to increase fluid excretion. Another option is imipramine before bed, which increases sodium and water reabsorption and may help with sleep.

Question 119

What should be considered when prescribing imipramine for nocturia?

Answer 119

When prescribing imipramine for nocturia, it’s important to consider whether a baseline electrocardiogram is necessary to assess the QTc interval. Additionally, it should be noted that imipramine can potentiate the hyponatremia risk of desmopressin.