Nocturia

What is Nocturia?

The term nocturia defines the need to get up several times during the night's rest to give vent to the repeated urge urge.

Normally, adults should be able to sleep for six to eight hours without having to wake up to urinate. In the case of nocturia, people interrupt their rest cycle more than once per night (a single episode of nocturia is within normal limits), resulting in an impact on sleep quality. Nocturia is a symptom and it is important to evaluate the underlying causes that cause it.

Causes

Trivially, nocturia could be an expression of "excessive fluid intake before going to bed (transient nocturia); at times, however, it represents the symptom of a pathological condition.

Pathological causes Non-pathological causes

• Metabolic problems and alterations in the water balance: diabetes, hyperparathyroidism, chronic renal failure, heart failure and other causes of peripheral edema.

• Nutrition (high-protein diet, intake of stimulating drinks or coffee);
• Pregnancy;
• Old age;
• Anxiety and stress;
• Menopause;
• Diuretic drugs.

• Neurological disorders affecting bladder control: multiple sclerosis, Parkinson's disease, spinal cord compression and cauda equina syndrome.

• Lower urinary tract disorders or bladder dysfunction: urinary incontinence, bladder infections, interstitial cystitis, ureteral obstruction, benign prostatic hypertrophy, prostate cancer, poor bladder capacity, detrusor muscle hyperactivity, decreased bladder distensibility, uterine fibroids, etc.

The underlying cause of nocturia can be identified through a "thorough medical evaluation, which may include:

• Anamnesis: evaluation of symptoms, drugs and liquids taken (including alcohol) + search for systemic diseases in progress that could contribute to nocturia;
• Examination of the abdomen, pelvic (women) and rectal (men);
• Blood tests: electrolytes, glucose, calcium, evaluation of renal function, etc .;
• Urinalysis and urine culture: to exclude local infections, haematuria and proteinuria;
• Urodynamics: evaluates urinary flow, residual volume and other parameters relating to impaired bladder function.

Symptoms

Urinary symptoms associated with nocturia Possible causes Polyuria
Production of a large amount of urine per day (greater than 2,500-3,000 ml in 24 hours).

• Excessive fluid intake
• Untreated diabetes (type 1 and type 2);
• Insipid diabetes;
• Gestational diabetes (during pregnancy);
• Hypercalcemia;
• Kidney failure.

Nocturnal polyuria
The body produces a large volume of urine during sleep (normal amount of urine in 24 hours with night volume greater than 35% of the total).

• Redistribution of fluid during the night due to heart failure and other causes of edema, such as venous stasis
• Sleep disturbances, such as obstructive sleep apnea;
• Some drugs (may depend on the time of day they are taken): diuretics, cardiac glycosides, demeclocycline, lithium, methoxyflurane, phenytoin, propoxyphene and excessive vitamin D;
• Excessive fluid intake before bed, especially caffeinated and alcoholic beverages;
• Impaired secretion of vasopressin (antidiuretic hormone), more common in the elderly.

Pollakiuria
Increased frequency of urination with emissions of small amounts of urine.

• Obstruction of the ureteral canal;
• Benign prostatic hyperplasia;
• Inflammation or cancer of the bladder, urethra or prostate.

Low nocturnal bladder capacity
More urine is produced at night than the bladder can hold. The need to empty the bladder causes a night awakening.

• Decreased bladder distensibility;
• Overactive bladder
• Pregnancy;
• Bladder or recurrent urinary tract infections
• Inflammation - for example, interstitial cystitis;
• Urethral pathology;
• Bladder cancer
• Prostate disease: benign prostatic hypertrophy, prostate cancer.

Mixed nocturia
Combination of nocturnal polyuria and low nocturnal bladder capacity. One of the possible causes listed for nocturnal polyuria associated with low nocturnal bladder capacity.

Treatment

Treatment depends on the type of nocturia and its cause. Treatment options for nocturia can include:

Medicines:

• Antidepressant drugs with anticholinergic action: they reduce the symptoms of overactive bladder by acting on the destrusor muscle and improving bladder emptying.
• Drugs that reduce urine production:
• Bumetanide and furosemide: diuretics which act by regulating the production of urine;
• Imipramine: tricyclic antidepressant which decreases urine production, also indicated for nocturnal enuresis;
• Desmopressin: Vasopressin analog that helps the kidneys produce less urine.

Interventions:

• Limit the evening consumption of coffee, alcohol and other beverages containing caffeine or theine (due to their diuretic effect);
• Adjust the time of taking diuretic drugs: prefer the late afternoon, about six hours before bedtime so that their therapeutic effect is complete before going to bed;
• Elevate your legs and wear compression stockings (to help prevent fluid retention).