How the Bladder Senses? A Five-Grade Measure

Area of Science:

• Urology
• Neuroscience
• Physiology

Background:

• Bladder filling elicits increasing sensation, but volume-sensory and pressure-sensory correlations in normal bladders and detrusor overactivity (DO) are not well understood.
• Detrusor overactivity (DO) is characterized by involuntary bladder contractions, often leading to urgency and incontinence.

Purpose of the Study:

• To develop and validate a real-time, five-grade measure for assessing bladder sensation.
• To investigate the volume-sensory correlation in normal bladders and the pressure-sensory correlation during DO.

Main Methods:

• A cohort of 74 healthy individuals and 87 patients with DO (51 terminal, 36 phasic) participated.
• Participants reported bladder sensations using a five-grade scale (1=first sensation, 5=strong desire to void) during slow bladder filling.
• Other sensations, including pain, were also recorded.

Main Results:

• The five-grade measure proved feasible for all participants, demonstrating a correlation between bladder volume/pressure and sensory perception.
• The duration of sensation grades 0-1 was longest, followed by 4-5, in all groups.
• Sensation progression was faster in DO patients (phasic and terminal) compared to normal bladders (P < 0.05).
• Eighty-six percent of DO patients equated the rapid sensory increase to their daily urinary urgency.

Conclusions:

• The five-grade measure is a viable tool for assessing volume and pressure-sensory correlations in bladder function.
• Detrusor overactivity is associated with a significantly accelerated sensory grade increase compared to normal bladder function.
• The findings support the clinical relevance of this measure in understanding and managing urinary urgency in DO.