Related Experiment Video
Updated: Jun 13, 2026
06:39
Real-Time Void Spot Assay
Published on: February 10, 2023
Age and Nocturnal Polyuria in Nocturia: A Multicenter Voiding Diary Cohort Study
Kota Kawase1, Yoshinori Nishino2, Kanako Matsuoka3
1Department of Urology, Graduate School of Medicine, Gifu University, Gifu, Japan.
Neurourology and Urodynamics
|June 12, 2026
Summary
Nocturnal polyuria (NP) prevalence increases with age, particularly in adults over 80. This condition is multifactorial, involving overactive bladder (OAB) and changes in urine volume, not just bladder function.
Area of Science:
- Gerontology
- Urology
- Internal Medicine
Background:
- Nocturnal polyuria (NP) prevalence rises with age, but underlying mechanisms and age-specific voiding patterns remain unclear.
- Understanding age-related voiding profiles is crucial for developing effective management strategies for nocturia.
Purpose of the Study:
- To analyze urinary patterns and clinical factors associated with nocturnal polyuria (NP) across different age groups.
- To clarify age-specific voiding profiles and identify predictors of NP.
Main Methods:
- A multicenter retrospective observational study involving 875 patients with nocturia.
- Voiding diaries were analyzed, and patients were stratified into five age groups.
- NP was defined by an NP index (NPi) > 0.33; clinical factors associated with NP were identified via multivariate analysis.
Main Results:
- NP prevalence and NPi significantly increased with age, peaking in the ≥80 years group.
- Older adults (≥80 years) exhibited lower 24-h and daytime urine volumes and higher NP incidence.
- Age, overactive bladder (OAB), maximal urinary volume, and 24-h urine volume were independent predictors of NP.
Conclusions:
- Nocturia in older adults is multifactorial, involving overactive bladder (OAB), altered urine volume, and comorbidities.
- Age-related changes in urine production and bladder function contribute to nocturnal polyuria.
- Targeting OAB and managing urine volume are key for addressing nocturia in aging populations.
Related Concept Videos
01:29Urine Studies I: Urinalysis
Urinalysis is a widely used diagnostic test that analyzes urine's physical, chemical, and microscopic characteristics. Healthcare providers use it to detect and monitor various health conditions, including renal disease, urinary tract infections (UTIs), diabetes, and metabolic or systemic disorders.Components of UrinalysisUrinalysis consists of three primary components: physical, chemical, and microscopic examination. Each provides unique insights into the urine sample and, by extension, the...
01:22Imaging Studies VI: Voiding Cystourethrography and Cystography
Voiding Cystourethrography (VCUG) and Cystography are specialized radiographic procedures used to examine the structure and function of the bladder and urethra.Voiding Cystourethrography (VCUG)A Voiding Cystourethrogram (VCUG) is a diagnostic imaging procedure that assesses the anatomy and function of the lower urinary tract. It focuses on the bladder, bladder neck, and urethra, helping detect abnormalities such as vesicoureteral reflux (VUR)—the backward or reverse flow of urine into the...
01:22Diabetes Insipidus II: Pathophysiology
Normally, water balance is maintained through three interconnected mechanisms: the hypothalamic thirst center, the synthesis and release of antidiuretic hormone (ADH, or vasopressin), and the kidneys' responsiveness to this hormone. ADH is synthesized in the hypothalamus, released from the posterior pituitary, and acts on the distal nephron, allowing water reabsorption and concentrated urine production.Diabetes Insipidus and Its TypesIn diabetes insipidus (DI), this regulatory system is...
01:26Urine Studies II: Urine Culture and Sensitivity Test
A urine culture and sensitivity test is a diagnostic procedure used to identify urinary tract bacterial infections and determine the most effective antibiotics for treatment. This test is generally preferred when a patient shows manifestations of a urinary tract infection, such as frequent or painful urination, cloudy or foul-smelling urine, or lower abdominal pain.Purpose of the TestThe primary goals of a urine culture and sensitivity test are to:Determine the specific bacteria causing the...
01:20Physiology of the Genitourinary System III: Urine Concentration and Dilution
The kidneys concentrate or dilute urine to maintain water and electrolyte balance. Nephrons, particularly the loop of Henle, play a crucial role in this process through the countercurrent multiplication system. This system establishes a high osmolarity in the renal medulla, which is essential for water reabsorption. In the loop of Henle’s descending limb, water is reabsorbed into the surrounding medulla due to its permeability to water. In contrast, the ascending limb actively transports...
01:19Urodynamic Studies: Uroflowmetry
Uroflowmetry is a non-invasive urodynamic test designed to measure various aspects of urination, including volume, flow rate, and the time to void. This test is crucial for diagnosing and assessing conditions such as bladder outlet obstruction, bladder dysfunction, incomplete bladder emptying, incontinence, and urinary tract blockages caused by benign prostatic hyperplasia (BPH) and urethral strictures.Pre-Test Instructions:Before a uroflowmetry test, patients are typically advised to drink...