Nocturia, Polyuria, and Nocturnal Polyuria: what are the differences?

Nocturia, polyuria, and nocturnal polyuria…these three terms that can be confusing for people without a medical background. What are the differences between the three conditions? This article will give you a brief introduction to help you understand their differences.

What is Nocturia?

First, nocturia is recognized as a symptomatic urinary disorder rather than a symptom of another disorder, causing one to wake up at night to urinate. Nocturia is more like an umbrella term describing the condition of having to urinate more often at night without specifying the amount of urine.

The leading cause of nocturia can be further categorized into polyuria and nocturnal polyuria and will be discussed in the following paragraphs.

What might cause Nocturia?

Many possible causes might result in nocturia, including:

A. Diabetes

B. Polydipsia

C. Diabetes insipidus

The commonly mentioned 3 P’s of Diabetes include polydipsia (an increase in thirst), polyuria (frequent urination), and polyphagia (a rise in appetite).

In addition to diabetes, one usually gets polydipsia as a symptom of other conditions, including schizophrenia, mood disorders such as depression and anxiety, Anorexia, and brain injuries and damage.

Diabetes insipidus, on the other hand, is a comparatively rare disease caused by the failure of the renal collecting duct to respond to antidiuretic hormones, resulting in an inability to concentrate urine, resulting in polyuria, clear urine, and increased thirst.

What are the symptoms of Nocturia?

Wake up more than once a night to urinate.
Urinating more volume (if polyuria is present).
Fatigue, sleepiness — even after waking up. This occurs because frequent urination can interrupt the sleep cycle.

What are the treatments for Nocturia?

Lifestyle adjustment

Reducing water intake during the four hours before bedtime can help reduce the amount of urination at night and improve the occurrence of nocturia.
Caffeine and alcohol intake in the evening also tend to increase nighttime urination and should be avoided as much as possible.
Know the correct drinking habits to ensure a reasonable amount of water and urine output.

Medication

Anticholinergic medications: can help reduce symptoms of an overactive bladder).
Bumetanide and Furosemide: diuretics that assist in regulating urine production
Desmopressin: helps the kidneys produce less urine.

C. Other treatments

Diabetes control: Good glycemic control can improve the patient’s polyuria symptoms.
Continuous positive airway pressure (CPAP): Studies have shown that improving patients’ obstructive sleep apnea (OSA) effectively reduces nocturia symptoms.
Medication to promote sleep: Helps reduce the number of times a patient wakes up early due to poor sleep quality.

2. Polyuria: Excessive Urine Production

It’s also essential to distinguish between nocturia (urinating too frequently at night) from Polyuria (too much volume).

So what is Polyuria? Adults usually make about 3 liters of urine per day. But with polyuria, one could make up to 3 L/day for adults and 2 L/m2 for children per day or approximately 40mL/kg per day in older children and adults.

Polyuria is different from having to urinate more often only at night. Instead, Polyuria refers to excessive urine production all day.

Common causes of Polyuria include:

Diabetes insipidus
Psychogenic polydipsia: most often in women after the age of 30

Less common causes of Polyuria include:

Kidney failure
Sickle cell anemia
Congestive heart failure
Hypercalcemia

3. Nocturnal Polyuria:

Nocturnal polyuria is a subset of polyuria, and it means voiding a high volume of urine in the nighttime or evening hours.

The definition of Nocturnal polyuria

In patients with nocturnal polyuria, 33% of the total daily urine output occurs at night, although the daily total urine output remains normal. A careful voiding diary, incorporating measurements of voided volumes, is essential to make the diagnosis.

Common causes of Nocturnal polyuria include:

Nocturnal polyuria without other diseases or complications is usually caused by a deficiency of the antidiuretic hormone in the body, which usually occurs in older people due to hormone imbalance in the body.

Some other possible causes of Nocturnal polyuria include:

Sleep apnea
Congestive heart failure
Lower extremity venous stasis

What are the treatments for Nocturnal polyuria?

Since nocturnal polyuria is a subset of nocturia, treatments and medications are sometimes overlapped. Nocturia and nocturnal polyuria are considered one of a wide range of symptoms associated with well-recognized lower urinary tract symptoms (LUTS), such as benign prostatic obstruction (BPO) and overactive bladder (OAB). Therefore, determining the root cause is essential to finding the proper antidote.

Lifestyle adjustment

If chronic diseases cause nocturnal polyuria, one must actively treat your own chronic conditions and follow the doctor’s advice. For example, patients with chronic heart failure need to reduce sodium intake, patients with hyperglycemia need to control blood sugar actively, and patient with sleep apnea needs to prevent snoring to reduce the symptoms and the frequency of nocturia.

Medication

The current medication for nocturia is mainly antidiuretic hormone, which has no side effects on the human body, but it is recommended to make a “urination diary” to clarify the cause of nocturia before receiving nocturia treatment.

Summary

Below is a hierarchy chart that helps you distinguish the differences between Nocturia, Polyuria, and Nocturnal Polyuria.