Which age-related change would the nurse associate with a patients report of nocturia

Evaluation

The cause of nocturia can be multifactorial and complex; therefore, the evaluation of nocturia should be focused and systematic, beginning with a complete history and physical examination. By way of example, a history of medication use, such as lithium, should alert the clinician to the possibility of global polyuria as a result of drug-induced nephrogenic diabetes insipidus. Physical findings pertinent to an evaluation of nocturia might include peripheral edema resulting from cardiac disease, nephrotic syndrome, or venous insufficiency and be associated with nocturnal polyuria. Physical findings such as obesity and short neck might be suggestive of obstructive sleep apnea (OSA); the latter also is associated with nocturnal polyuria. In the population-based Finnish National Nocturia and Overactive Bladder (FINNO) study, numerous risk factors for nocturia were identified, such as urinary urgency, benign prostatic hyperplasia (BPH), snoring, obesity, antidepressant usage, restless legs syndrome, and prostate cancer in men, and obesity, urinary urgency, snoring, diabetes, restless legs syndrome, and coronary artery disease in women. However, none of the identified risk factors were associated with nocturia in more than 50% of the affected subjects of both sexes, highlighting the multifactorial cause of nocturia (Tikkinen et al., 2009a). Hence, it is essential that clinicians consider factors beyond the LUT when treating bothersome nocturia.

Some of the questions to consider when evaluating nocturia are: How is nighttime defined? Is the patient awakened by the need to void, or does the patient void because he or she is already awake? A recent study byWeinberger et al. (2013) showed that 92% of men and 90% of women are awakened by the urge to void, leaving the remainder as incidental nocturnal convenience voids.Nighttime is defined as the period between going to bed with the intention of sleeping and awakening with the intention of arising (van Kerrebroeck et al., 2002). This definition becomes relevant when explaining to the patient how to complete a 24-hour voiding diary orfrequency-volume chart, the most valuable objective instrument in evaluating nocturia. When completing a frequency-volume chart, the patient must be aware that nocturnal voids are preceded and followed by the intention of sleep regardless of time of day. Because at least 16% of the US population consists of shift workers who occasionally sleep during the day, it is important to remember that nocturia may occur during the day (Beers, 2000). Changing time zones (jet lag) also complicates the definition of nighttime. Before having a patient complete a frequency-volume chart, it is best to allow sufficient recovery time to eliminate the effect of jet lag.

Although the first-morning void after a night's sleep is counted toward daytime (diurnal) frequency rather than the ANV, the volume of the first-morning void is included in the tally of nocturnal voided volume. Hence,nocturnal urine volume (NUV) is the sum of all nocturnally voided volumes plus that of the first-morning void, because the urine in the latter void is produced during the hours of sleep. An untested assumption is that most patients void before bedtime. Hence the first nocturia-related void is also assumed to have been excreted during the hours of sleep.Maximum voided volume (MVV) is the largest voided volume of urine during a 24-hour period. The nocturia index (Ni) is calculated by dividing NUV by MVV (Weiss et al., 1999). When NUV is greater than MVV, the Ni is greater than 1, in which case nocturia must occur if the patient awakens, and, if not, enuresis will occur. Epstein et al. showed that improvements in nocturia were associated with a decrease in 24-hour urine volume and NUV, but not MVV, suggesting that improved patients consumed less fluid (Epstein et al., 2018). Improved patients also had an increase in FUSP, suggesting that therapy for nocturia can improve sleep architecture.

Prevalence

Nocturia is uncommon in young adults, but its prevalence increases substantially with age, becoming quite common in the elderly. In a community phone survey of nearly 5000 people with an average age of 46 years, 31% reported voiding at least once per night, and 14% voided twice or more. In another study, 80–90% of men aged 80 years or greater reported nocturia, with 30% having more than one episode per night. The prevalence of nocturia is felt to be equal among men and women.

Often, patients feel nocturia is an expected part of aging. They will self-treat with interventions such as evening fluid restriction, and thus not report their symptoms until they are intolerable. In addition to being a bothersome symptom, nocturia may be indicative of an underlying disorder such as diabetes, cardiopulmonary disease, or urinary obstruction or retention. As with other underreported illnesses, an appreciation of the high prevalence, significant impact on quality of life, and potentially serious sequelae of nocturia is imperative.

Nocturia

Nocturia is one of the most common and bothersome urinary conditions that occurs in elderly patients (Wehrberger et al., 2012;Weiss and Blaivas, 2000). The ICS defines nocturia as “getting up from sleep in order to void” (Abrams et al., 2002). This is generally preceded and followed by additional episodes of sleep. Polysomnography studies have documented that a majority of episodes of nocturia occur during superficial rapid eye movement (REM) sleep (Bal et al., 2012;Krystal et al., 2010). However, waking to urinate can also lead to difficulty getting back to sleep with 46% of older adults in one survey reporting this as a substantial clinical problem (Endeshaw, 2009). Affected older adults also report worse disease burden, poor overall sleep quality, and an increased rate of falls compared with those who fall back to sleep more easily. Sleep duration is often decreased in older adults, and this has been identified as an independent risk factor for nocturia in elderly patients (Udo et al., 2009). Several biochemical processes appear to influence nocturia and nocturnal polyuria. Obstructive sleep apnea results in decreased antidiuretic hormone (ADH) secretion and increased brain natriuretic peptide (BNP), which can lead to nocturnal polyuria (Hoshiyama et al., 2014). Nighttime melatonin secretion is inversely proportional to nocturia in older adults (Obayashi et al., 2014). Worse nocturia severity has also been linked to progression of underlying neurologic disorders such as Parkinson disease (Vaughan et al., 2013). Improved understanding of these complex associations between comorbid conditions and nocturia may help to improve future options for diagnosis and treatment.

The epidemiology of nocturia is complex and is linked to underlying risk factors associated with the condition. There appear to be some underlying differences in nocturia between men and women resulting from a variety of anatomic and physiologic factors (Bing et al., 2007, 2008;Tikkinen et al., 2006). An epidemiologic survey of 6000 people in Finland revealed multiple associated conditions, including urinary urgency, snoring, BPH in men, and overweight and obesity (Tikkinen et al., 2009). At an individual level, urinary urgency appears to be one of the strongest correlated conditions. However, none of the conditions studies accounted for more than 50% of cases, even in age-adjusted risk analysis. Some modifiable behavioral factors have also been associated with nocturia, including alcohol consumption and cigarette smoking (Lee et al., 2012). Symptoms of nocturia can change over time and may resolve spontaneously in some cases (Pesonen et al., 2016).

Nocturia can have a substantial negative impact on quality of life. In general, one episode of nocturia per night is well tolerated by most people and is usually considered normal. However,two or more episodes of nocturia nightly have been linked to diminished sleep quality, reduced overall and health-related quality of life, and other detrimental clinical outcomes (Tikkinen et al., 2010). Nocturia has also been linked to depression in longitudinal research (Obayashi et al., 2017). Increased rates of morbidity and mortality have been linked to nocturia (van Doorn et al., 2012).Worse nocturia severity has been directly correlated with increased rates of complication including falls, fractures, and other negative clinical outcomes (Bing et al., 2007, 2008). This association appears to be independent of age and is more associated with severity of nocturia (Temml et al., 2009). This is true in community-dwelling older adults and those living in nursing homes and other facilities (Galizia et al., 2012).Falls are associated with increased rates of hip and long bone fractures, which in turn increase the risk for immobility and mortality (Nakagawa et al., 2010). Fat embolization from bone fractures can cause stroke and pulmonary embolus. Falls associated with nocturia can be caused by a number of factors, including problems with balance and gait, attempting to travel to the toilet in the dark, navigating obstacles that may be in the path to the bathroom, and other factors.

Nocturia

Nocturia is a particularly troublesome symptom of aging, and it appears to be related to the severity of sleep-disordered breathing. Because older persons with significant sleep-disordered breathing might not manifest classic symptoms of OSAH, the presence of nocturia in the older patient should heighten the clinical suspicion for OSAH. Indeed, nocturnal urination of more than three times per night had a positive and negative predictive values of 0.71 and 0.62 for severe OSA in one study.32

The postulated mechanism of nocturia in OSAH is that the negative intrathoracic pressures resulting from occluded breaths cause distention of the right atrium and ventricle. This right-sided cardiac distention results in release of atrial natriuretic peptide (ANP), which inhibits the secretion of antidiuretic hormone (ADH) and aldosterone and causes diuresis through its effect on glomerular filtration of sodium and water.33

Several studies have demonstrated improvement in nocturia with use of continuous positive airway pressure (CPAP).34-36 CPAP might improve nocturia by allowing the normal nocturnal rise in ADH, resulting in increased resorption of sodium and water from the collecting tubules and production of lower volumes of more-concentrated urine.37 In a retrospective review of 196 patients whose mean age was 49 years, predictors of nocturia included increasing age and diabetes mellitus. Although a complaint of nocturia was equally likely to occur in patients with and without OSAH, frequency of nocturia was significantly related to age, diabetes, and severity of sleep-disordered breathing in patients who had OSAH. Patients with OSAH and nocturia who were treated with CPAP experienced significant reductions in the frequency of nocturnal voiding.38 In a study of 21 women with a mean age of 65 years, the same group of investigators reported that OSAH is present in a majority of women with nocturia and that the presence of diluted nighttime urine in a patient with nocturia is a sensitive marker for OSA.39

Nocturia

It is becoming recognized that nocturia, especially when occurring in isolation from other LUTS, represents a symptom with its own unique set of possible physiologic causes (Van Kerrebroeck and Andersson, 2014) includingglobal polyuria, nocturnal polyuria, reduced bladder capacity, sleep disorders, heart failure, and circadian clock disorders. It has been shown that themouse bladder exhibits circadian rhythms in expression of Cx43 (Negoro et al., 2012) and furthermore that Cx43 regulates bladder capacity in dark and light cycles of the mouse. During the light cycle, when the mouse is not active (equivalent to the human sleep cycle), Cx43 is downregulated, leading to increased bladder capacity (increased measure of volume voided per micturition). Conversely, during the dark cycle, when the mouse is awake and active, Cx43 is upregulated and bladder capacity is reduced (decreased volume voided per micturition). Transgenic animals with one of the circadian transcriptional regulators, Cry, knocked out developed loss of circadian oscillations of bladder capacity associated with loss of Cx43 expression oscillations. This study suggested that loss of the biologic clock mechanism in regulating Cx43 within the bladder may be a contributing mechanism to nocturia and nocturnal enuresis.

Nocturia

Nocturia is a particularly troublesome symptom of aging and appears to be related to the severity of sleep-disordered breathing. Because older adults with significant sleep-disordered breathing may not manifest classic symptoms of OSA, the presence of nocturia in the older patient should heighten clinical suspicion for OSA. Indeed, nocturnal urination more than three times nightly had positive and negative predictive values of 0.71 and 0.62, respectively, for severe OSA in one study.41

The postulated mechanism of nocturia in OSA is that the negative intrathoracic pressures resulting from occluded breaths cause distention of the right atrium and ventricle. This right-sided cardiac distention results in release of atrial natriuretic peptide, which inhibits the secretion of antidiuretic hormone and aldosterone and causes diuresis through its effect on glomerular filtration of sodium and water.42 Several studies have demonstrated symptomatic improvement in patients with nocturia with use of CPAP.43-45 The mechanism of CPAP-related improvement may involve promoting the normal nocturnal rise in antidiuretic hormone, resulting in increased resorption of sodium and water from the collecting tubules and production of lower volumes of more concentrated urine.46 In a retrospective review of data on 196 patients whose mean age was 49 years, predictors of nocturia included increasing age and diabetes mellitus. Although a complaint of nocturia was equally likely to occur in patients with and without OSA, nocturic frequency was significantly related to age, diabetes, and severity of sleep-disordered breathing in those patients who had OSA. Furthermore, patients with OSA and nocturia who were treated with CPAP experienced significant reductions in the frequency of nocturnal voiding.47 In a study of 21 women with a mean age of 65 years, the same group of investigators reported that OSA is present in a majority of women with nocturia, and that the presence of diluted nighttime urine in a patient with nocturia is a sensitive marker for OSA.48

Nocturia

Nocturia is defined as a regular need to awaken to void, needing to void more than once per night, or an excessive volume of nighttime urine. In contrast, convenience voiding occurs in the context of an awakening due to an alternate cause (Leslie et al., 2021). The association of nocturia and OSA is well established. A retrospective review of 1970 largely middle aged OSA patients found OSA severity was associated with number of episodes of nocturia after adjusting for age; patients with severe OSA were particularly effected (Oztura et al., 2006). A meta-analysis of 13 studies (case control, prospective, and retrospective) in subjects with OSA found relative risk of 1.4 for nocturia, defined as 2 or more voids during the sleep period. Risk was 1.26 for mild to moderate OSA and 1.47 for severe OSA compared to no OSA (Zhou et al., 2020).

A combination of mechanisms causes increased urine production in OSA. Elevated nocturnal atrial natriuretic peptide is induced by hypoxia along with cardiac distention caused by apnea generated negative intrathoracic pressures (Umlauf and Chasens, 2003). Concurrently, vasopressin, an antidiuretic hormone produced by the hypothalamus, is inhibited by atrial natriuretic peptide, sleep cycle disruption, and non-dipping of nocturnal blood pressure (Leslie et al., 2021).

A prospective uncontrolled study of nocturia frequency in 97 OSA patients before and after PAP treatment, showed a statistically significant reduction in nocturia after initiation of therapy from an average of 2.5 episodes per night to less than 1 with greater improvement in those with severe OSA (Margel et al., 2006). Furthermore, a meta-analysis of 5 prospective, pre/post-PAP treatment studies of 307 subjects found significant reduction of overnight voiding episodes and urine volume (Wang et al., 2015). Mechanistic plausibility and response to treatment lend support to direct causation.

Nocturia

Nocturia describes waking at night to urinate. It is more common in older adults, but no population data define a normal range for any group; therefore the complaint implies a deviation from a perceived norm. Furthermore, the primary complaint often centers on the sleep disturbance rather than on urination. It may represent frequent nocturnal urination or excessive nocturnal urine production (nocturnal polyuria). Although often thought of as a prostatic symptom, it is common in both men and women. The many secondary causes in addition to local causes include prostatic hyperplasia and bladder dysfunction (Box 40-4). In patients with prominent lower urinary tract symptoms, the problem is compounded by urination difficulty. Furthermore, studies in older adults indicate that nocturia/LUTS increases risk of falling (Parsons, et al., 2009). Age-related variations in arginine vasopressin secretion may play a role in nocturnal polyuria (Weiss and Blaivas, 2000).

Treatment centers on the underlying cause, and a voiding diary may aid clinical decisions. Prostate hyperplasia or bladder dysfunction often receives first attention. Treating BPH may help, although BPH often does not result in true physical obstruction, and epidemiologic data have indicated that nocturia is common in men without prostatic obstruction. Thus, family physicians should consider the contribution of nocturnal polyuria. For example, patients with chronic heart failure and leg edema may benefit from fluid restriction and napping with leg elevation during the day. Treating obstructive sleep apnea helps alleviate the increased urine production resulting from increased atrial natriuretic peptide production. Behavioral interventions include avoiding excess nighttime alcohol or fluid intake and afternoon napping. Adjusting diuretic doses so they are given earlier in the evening should negate medication effects during sleep (Weiss and Blaivas, 2000).

Nocturia/Impotence

The association of nocturia and OSA has been demonstrated in several retrospective and cross-sectional studies. A cross-sectional study of 58 patients with severe OSA showed a significant increase in nocturia episodes compared to those with lesser or no OSA. A subsequent prospective uncontrolled study of nocturia frequency in 97 OSA patients before and after CPAP treatment showed a statistically significant reduction in nocturia after initiation of therapy. The proposed mechanism for nocturia is the release of atrial natriuretic factor secondary to cardiac distention caused by apnea-generated negative intrathoracic pressures.

A recent cross-sectional study of over 400 men presenting for polysomnogram (PSG) showed that erectile dysfunction (ED) was present in 69% of men diagnosed with OSA. This result was more than twice the prevalence in men without OSA. The study further identified mean nocturnal oxygen saturation as an independent predictor of ED. A recent randomized controlled study demonstrated a subjective improvement in ED in OSA patients after treatment with CPAP. In summary, nocturia and ED are bothersome symptoms of OSA which are frequently associated with reduced QOL and potentially reversed with CPAP therapy.

Clinical Characteristics

Symptoms include nocturia and urinary frequency, reflecting the urinary concentrating defect induced by the potassium deficit. In patients with more severe hypokalemia, other manifestations including muscular weakness, frontal headaches, polydipsia, paresthesias, visual disturbances, temporary paralysis, cramps, and tetany may occur. If the patient is normokalemic, these characteristic symptoms are usually mild or absent.

Patients with an adenoma, however, usually have more extensive manifestations of mineralocorticoid excess than those with hyperplasia, including more severe hypertension. The physical examination is not usually distinguishable from primary hypertension, unless hypokalemia is severe. Serum potassium levels are significantly lower in adenoma patients (<2.8 mEq/L in >40%) compared with patients with hyperplasia (<2.8 mEq/L in <10%). The profound hypokalemia that occurs in patients with an adenoma contributes to the development of a metabolic alkalosis.