Definition
A.Nocturia is frequent wakefulness at night to urinate. The American Urological Association (AUA) and the International Continence Society (ICS) define nocturia as the need to awake in order to urinate at least once or twice during the night.
Most individuals describe their nocturia progressing from having an episode occasionally to having one or more episodes nightly.
B.Nocturia in the older population is associated with higher rates of accidental falls and fractures.
C.Nocturia is a leading cause of sleep disturbance affecting sleep onset, difficulty returning to sleep following nighttime awakening, and sleep deprivation associated with morning fatigue having a negative impact on quality of life.
D.Nocturia is associated with increased rates of depression and work absenteeism.
E.Occasionally nocturia can be an indicator of worsening clinical status of an underlying disease, such as chronic kidney disease (CKD), lithium toxicity, diabetes, or congestive heart failure (CHF).
Incidence
A.The prevalence of nocturia increases with age.
B.Some studies suggest that nocturia is present in 50% of both men and women older than 50 years of age.
C.Among those 18 to 49 years old, more women than men experience nocturia.
D.Men older than 60 years of age experience nocturia more than women.
E.The prevalence of twice nightly or greater nocturia among men between the ages of 70 and 79 years is nearly 50%.
F.Nocturia associated with pregnancy nearly always resolves by 3 months postpartum.
Pathogenesis
A.Aging is a major factor, and nocturia occurs more commonly in the elderly than in younger individuals.
B.Nocturia can be attributed to any disorder or condition that causes one of the following:
1.Low-volume bladder void because of reduced bladder capacity or impaired bladder function.
2.Increased volume of nighttime urinary output.
3.Sleep disturbance.
C.In both women and men, the occurrence is much different because of the dissimilarity of the respective anatomy:
1.In women, nocturia is generally experienced as a result of childbirth, menopause, and pelvic organ prolapse.
2.Nocturia in men, however, can be directly attributed to enlarged prostate causing a bladder outlet obstruction (BOO).
Predisposing Factors
Multiple factors could cause nocturia in both men and women, including the following:
A.Chronic diseases:
1.Diabetes.
2.Heart failure/venous status (third spacing of fluids).
3.Diabetes insipidus and uncontrolled diabetes mellitus (DM).
4.Primary polydipsia (nocturnal polyuria).
5.CKD.
6.Obstructive sleep apnea (OSA).
7.Neurologic diseases.
8.Obesity.
9.Age-related defect in diurnal secretion of arginine vasopressin (AVP) in the elderly.
B.Medications:
1.Diuretics.
2.Calcium channel blockers.
3.Beta-blockers (associated with bladder storage problems).
4.Xanthines (associated with bladder storage problems).
5.Selective serotonin reuptake inhibitors (SSRIs).
6.Cholinesterase inhibitors.
7.Lithium.
8.Corticosteroids.
C.Caffeine.
D.Alcohol.
E.Nocturnal polyuria.
F.Low nocturnal bladder capacity.
G.Combination of the nocturnal polyuria and low nocturnal bladder capacity.
H.Overactive bladder (OAB).
I.Gender:
1.Males:
a.Benign prostatic hypertrophy (BPH).
b.Prostate cancer.
2.Females:
a.Pregnancy.
b.Estrogen deficiency.
c.Pelvic floor laxity (e.g., cystocele, uterine prolapse).
J.Excessive fluid intake in the evening.
K.Interstitial cystitis/painful bladder syndrome (IC/PBS).
L.Chronic or recurrent UTIs.
M.Idiopathic.
N.Fecal impaction.
Common Complaints
A.Morning fatigue.
B.Frequent wakefulness.
C.Insomnia.
D.Urinary frequency.
E.Urinary urgency.
F.Geriatrics:
1.May not present with classic symptoms.
2.Incontinence.
3.Mental confusion.
4.History of falls.
Other Signs and Symptoms
A.Asymptomatic.
B.Bladder spasms.
C.Suprapubic pain or suprapubic discomfort.
D.Depression.
Subjective Data
A.Review the onset, course, and duration of symptoms.
B.Review the number of sleep interruptions or frequent wakefulness. Ask an open-ended question: Over the past month, how often did you typically get up at night to urinate, from the time you went to bed until the time your got up in the morning?
C.Are there any other genital problems such as herpes lesions or vaginal discharge?
D.Review all medications, prescriptions, over-the-counter (OTC) drugs, and herbals for how often
and what time of the day they are taken.
E.Does the patient have a fever and chills or back or flank pain (unilateral or bilateral)?
F.Is the patient pregnant? If not, what type of birth control does she use?
G.Is there any history of previous UTIs? How often, and how were they treated? Were any tests performed in a workup by a urologist?
H.Is there any history of IC? Were any tests performed in a workup by a urologist? What treatments?
I.In the postmenopausal woman, review whether she has a known prolapse and/or vaginal atrophy. Does she use any systemic or local estrogen medications?
J.How much liquid or water does the patient drink every day?
1.Note the amount of caffeine and alcohol.
2.Note the total amount of fluids.
3.At what time in the evening are the last fluids taken?
4.Does the patient awaken at night and drink more liquids?
K.In older men, review the strength of the urinary flow, dribbling, hesitancy, and so on.
L.Is there any history of other medical diseases (noted in the section Predisposing Factors
)?
M.Does the patient have a mobility issue and use any aids, such as a cane or a walker?
N.In the elderly, what is the patient’s ability to toilet independently?
Physical Examination
A.Both genders:
1.Check temperature (if an infection is suspected), pulse, blood pressure (BP), and respirations. Measure height and weight to calculate body mass index (BMI).
2.Inspection begins as the patient comes into the examination room:
a.Assess cognitive and functional status.
b.Observe mobility (including use of a walker, cane, or other aid).
c.Assess for risk of falls.
d.Observe patient to transfer.
e.Assess manual dexterity (ability to use buttons and zippers).
f.Inspect for evidence of cardiac overload: pedal edema.
3.Auscultate:
a.Auscultate the lungs for evidence of fluid overload: Rales.
4.Palpate:
a.Palpate the abdomen.
b.Palpate suprapubic and back for costovertebral angle (CVA) tenderness.
c.Palpate inguinal nodes for CVA tenderness.
d.Palpate bladder fullness and need for catheterization.
e.Perform a neurologic examination to determine presence of perineal sensation and anal wink (visual or palpated anal contraction in response to a light scratch of the perineal skin lateral to the anus).
5.Screen for depression.
B.Females:
1.Inspect perineal skin for irritation, thinning, vaginal atrophy, and vaginal discharge.
2.Perform a bimanual pelvic exam for prolapse, masses, or tenderness:
a.Remove the top blade of the speculum and evaluate the vaginal wall support.
b.Ask the woman to cough to reevaluate the vaginal wall support.
3.Palpate:
a.Perform rectal exam for sphincter tone, masses, and fecal impaction.
C.Males:
1.Inspect:
a.Inspect the glans penis for abnormalities in urethral meatus. (Hypospadias may cause postvoid dribbling.)
b.Uncircumcised men should be evaluated for phimosis and balanitis.
2.Palpate:
a.Perform rectal exam for sphincter tone, masses, fecal impaction, prostate size, and contour.
b.Palpate the scrotum to evaluate masses.
c.Evaluate the presence of an inguinal hernia since straining with a partial urinary obstruction can worsen an inguinal hernia.
Diagnostic Tests
History, physical examination, and urinalysis may be sufficient to guide initial therapy and to rule out other causative factors. Other tests include the following:
A.Urine culture and sensitivity if infection is suspected.
B.Urine cytology if hematuria or pelvic pain is present.
C.Urodynamic testing is strongly recommended.
D.A prostate-specific antigen (PSA) should be considered.
E.Cystoscopy/ureteroscopy.
F.Renal ultrasound with Doppler.
G.Renal function, electrolytes, glucose, and hemoglobin (Hgb) AIC.
H.Sleep study may be indicated, especially if positive for nocturnal hypoxemia.
I.Depression screen.
J.Neurological evaluation may be needed.
K.Nocturnal pulse oximetry study.
L.Patients with neurologic conditions affecting the bladder (diabetic neuropathy), older men, and patients with a history of genitourinary (GU) surgery are at risk for urinary retention.
1.Postvoid residual (PVR) by catheterization or ultrasound (a PVR of <50 mL is considered adequate emptying, and a PVR >200 mL may require referral for further evaluation).
Differential Diagnoses
A.Nocturia (idiopathic).
B.Nocturnal polyuria.
C.Low nocturnal bladder capacity.
D.DM/insipidus.
E.Medication(s) side effect.
F.Fluid intake near bedtime (includes caffeine and alcohol).
G.Chronic or recurrent UTI.
H.Enlarged prostate.
I.Pregnancy.
J.IC/PBS.
K.Congestive heart failure (CHF)/vascular stasis.
L.Heart disease.
M.Sleep disturbance.
N. 
See Section III: Patient Teaching Guide “Safety Issues: Fall Prevention.“
1. See Section III: Patient Teaching Guide Nocturia.
O.Section III: Patient Teaching Guide Urinary Incontinence: Women.
P.Nonpharmacological treatments:
1.Limit fluid intake at night, esecially alcohol and caffeine.
2.Move the nighttime diuretic dose to the midafternoon if the patient requires twice-daily diuretic medications.
3.If edema and venous stasis in the lower extremities are a problem, have patient wear compression stockings and elevate legs during the waking hours and remove stockings prior to retiring.