Nocturia (synonyms: nocturnal urination; nocturnal urination; nocturnal urination; nocturnal urination; nocturnal urination; ICD-10-GM R35: Polyuria: nocturia) refers to increased urine production during the night, so that the affected person has to go to the toilet several times during the night.
Occasional nocturia is normal. However, it can also be the symptom of many different diseases.
Nocturia can be the cause of polyuria (> 1.5-3 l/day; increased urine output), pollakiuria (urge to urinate frequently without increased urine output), or polydipsia (> 4 l/day; increased thirst) (see there).
Classification of nocturia:
- Global polyuria: excretion of > 40 ml/kg in 24 hr.
- Nocturnal polyuria (= actual form of nocturia): total urine output over 24 hr is unremarkable, but nocturnal output (including morning urine) is at:
- Young adults more than 20% of the 24-hour urine output.
- Over 65-year-olds more than 33% of 24-hour urine production.
- Decreased urinary bladder capacity (storage capacity of the bladder): frequent emptying of small amounts < 250 ml.
Nocturia can be a symptom of many diseases (see under “Differential diagnoses”).
Frequency peak: age is the main risk factor for nocturia. In young people, nocturia occurs very rarely. Females: In the 2nd-3rd decade of life, women are more often affected by nocturia than men. Men: In the 7th-8th decade of life, men are more frequently affected than women: 77% of women and 93% of men (due to the age-related increase of benign prostatic hyperplasia, BPH; guartige Prostatavergrößerung).
Course and prognosis: If nocturia persists for a longer period of time and is not due to the fact that the affected person has drunk a lot before going to bed, further clarification should be carried out. Getting up several times during the night can lead to increased daytime sleepiness, headaches, and concentration problems due to the difficulty sleeping through the night, thus impairing the quality of life. The elderly also have increased risks for decreased cognitive performance, falls, and fractures (broken bones).
