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Updated: Jan 14, 2026
Real-Time Void Spot Assay
Published on: February 10, 2023
The impact of daytime diuresis on voiding frequency and incontinence classification in children
Birgitte Mahler1, Soren Hagstroem, Nikolaj Rittig
1Clinical Institute, University of Aarhus, Aarhus, Denmark. mahler@ki.au.dk
Insights
Daytime voiding frequency in children with incontinence is primarily driven by urine production (diuresis), not bladder capacity. Monitoring diuresis is key when analyzing voiding patterns from frequency-volume charts.
Area of Science:
- Pediatric Urology
- Child Health
- Nephrology
Background:
- Daytime voiding frequency is a critical factor in diagnosing childhood incontinence.
- Understanding the determinants of voiding frequency is essential for effective management.
Purpose of the Study:
- To investigate the relative contributions of diuresis and bladder capacity to daytime voiding frequency in children.
- To differentiate between factors influencing voiding frequency in incontinent children and healthy controls.
Main Methods:
- Analysis of data from 570 children (4-15 years) with urinary incontinence and 87 healthy controls.
- Calculation of daytime voiding frequency, age-adjusted maximum voided volume, daytime diuresis, and fluid intake using frequency-volume charts.
- Classification of children into decreased, normal, and increased daytime voiding frequency groups.
Main Results:
- Daytime diuresis significantly differed across voiding frequency groups in children with daytime symptoms (p <0.001).
- Bladder capacity did not significantly differ between normal and increased frequency groups, but was higher in the decreased frequency group (p <0.01).
- A positive correlation was observed between fluid intake and diuresis (r = 0.53, p <0.001).
Conclusions:
- Daytime voiding frequency in children, both with and without incontinence, is predominantly influenced by diuresis.
- Bladder capacity appears to have a lesser impact on daytime voiding frequency compared to diuresis.
- Diuresis is a crucial parameter to consider when interpreting frequency-volume charts in pediatric voiding evaluations.
Purpose:
Daytime voiding frequency is an important criterion in the classification of childhood incontinence. The aim of this study was to assess the relative impact of diuresis and bladder capacity on voiding frequency.
Materials And Methods:
We analyzed data from 570 children 4 to 15 years old (median age 8.3 +/- 2.0 years) treated for urinary incontinence at a secondary referral center, and 87 healthy controls. Based on frequency-volume charts, daytime voiding frequency, age adjusted maximum voided volume, daytime diuresis and fluid intake were calculated. Children were classified according to voiding frequency into 3 groups-decreased (fewer than 3 voids daily), normal (3 to 7) and increased voiding frequency (more than 7).
Results:
A total of 219 children had monosymptomatic enuresis, while 351 children presented with daytime symptoms. In children with daytime symptoms we found a significant difference between voiding frequency groups regarding daytime diuresis (decreased voiding frequency 12.3 +/- 4.1 ml/kg, normal 18.7 +/- 6.0 ml/kg, increased 31.1 +/- 9.8 ml/kg, p <0.001). In contrast, maximum voided volume observed/expected bladder capacity for age did not differ significantly between normal and increased frequency groups (72% +/- 25% vs 74% +/- 23%), compared to patients with decreased voiding frequency (89% +/- 30%, p <0.01). Also, in healthy children we found a positive correlation between voiding frequency and daytime diuresis, whereas maximum voided volume observed/expected bladder capacity for age did not correlate with voiding frequency. Furthermore, we observed a significant positive correlation between fluid intake and diuresis (r = 0.53, p <0.001).
Conclusions:
In healthy controls and children with incontinence daytime voiding frequency depends mainly on diuresis, and seems less influenced by bladder capacity. Diuresis should be taken into consideration when evaluating voiding frequency from frequency-volume charts in children.
