Nocturia is a term used to describe the need to pass urine at night. Waking up more once to pass urine at night is considered to be nocturia, but patients may be waking up with the urge to urinate hourly or more frequently. It is normal for urine to decrease in amount and become more concentrated at night. Most people can sleep 6 to 8 hours without having to urinate. Middle aged or older men may normally have to urinate once in the early morning hours. Patients with cardiac failure may experience nocturia, as may elderly patients who often pass more urine at night as blood flow to the kidneys is increased when lying flat. Nocturia is a common problem in Australia. Men and women are equally affected, and by 80 years of age, over 50% of men and women will be waking 2 or more times per night to pass urine. It is a significant problem in the community, causing sleep deprivation and affecting quality of life.

Causes

There are many common causes of nocturia, which include:

  • Excessive fluid intake, particularly before bedtime
  • Excessive coffee, caffeinated beverages and alcohol intake, particularly at night.
  • Enlargement of the prostate gland, particularly in men over 50 years of age
  • Diabetes mellitus
  • Urinary tract infection
  • Chronic heart failure
  • Heart failure
  • Medications such as diuretics (fluid tablets), lithium and heart medications
  • Habit
  • Sleep disorders such as insomnia which cause secondary nocturia

What to expect at the doctor

The doctor may ask you many questions about your symptoms.
They may perform a full physical examination and order some tests, such as:

  • Urinalysis and culture
  • Blood tests to check renal function
  • Frequency/volume chart: including type, time and amount of fluid intake, time and amount of urine passed
  • ultrasound scanning of the bladder to check for urine retention
  • A specialist may order further tests such as urodynamics and sleep studies

Treatment

Treatment options vary depending on the cause of frequent night time urination. If an infection is the cause of nocturia, this will be treated with antibiotics. For more complex causes, patients will probably benefit from referral to a urologist (specialist in urinary problems). In general, management may take a conservative (no medications/surgery), medical or surgical approach. Conservative measures may involve bladder training exercises, keeping a bladder diary and reducing amount of fluids taken at night. Medical treatments include hormone treatments for post-menopausal women (if appropriate) and treating diabetes mellitus. Surgical management might be considered in the case of prostatic enlargement for men with significant symptoms.

References