Urodynamic Investigation: A Valid Tool to Define Normal Lower Urinary Tract Function?

Area of Science:

• Urology
• Lower Urinary Tract Symptoms Research
• Clinical Trial Methodology

Background:

• Urodynamic investigation (UDI) is the gold standard for evaluating lower urinary tract symptoms (LUTS).
• Selecting appropriate control subjects is crucial for comparative studies on LUTS.
• The utility of UDI in defining normal bladder function in healthy individuals remains unclear.

Purpose of the Study:

• To assess the appropriateness of UDI for selecting healthy volunteers as control subjects.
• To determine if apparently healthy individuals exhibit normal lower urinary tract function via UDI.
• To evaluate the reliability of UDI in a healthy cohort for comparative research.

Main Methods:

• 42 healthy subjects without LUTS underwent a 3-day bladder diary, LUTS questionnaires, and neuro-urological assessment.
• Free uroflowmetry was performed, followed by same-session repeat UDI using air-charged catheters.
• A blinded investigator evaluated the UDI results according to International Continence Society guidelines.

Main Results:

• All baseline assessments (bladder diary, questionnaires, uroflowmetry) were normal.
• Repeat UDI revealed pathological findings in 71% of healthy subjects.
• Common findings included detrusor overactivity, high post-void residual, bladder outlet obstruction, and detrusor sphincter dyssynergia.

Conclusions:

• UDI identified abnormalities in a significant majority of healthy individuals.
• UDI is not recommended for selecting healthy control subjects due to its low specificity in this population.
• The findings challenge the use of UDI to establish normative data for lower urinary tract function.