Noninvasive Pressure Flow Studies in the Evaluation of Men with Lower Urinary Tract Symptoms Secondary to Benign Prostatic Hyperplasia: A Review of 50,000 Patients

Abstract

Purpose: The UroCuff® Test is a noninvasive pressure flow study used to manage men with lower urinary tract symptoms. UroCuff Tests were performed on men with lower urinary tract symptoms to evaluate voiding characteristics and quantify changes in urodynamic parameters with age.

Materials and methods: This cross-sectional study included all UroCuff Tests performed at 103 urology practices in the U.S. Tests were de-identified prior to collection and analysis. Inclusion criteria required initial pressure flow study with subsequent tests excluded, voided volume 50 ml or greater, at least 1 cuff inflation and patient age greater than 20 years. Pressure, maximum flow rate, flow rate efficiency (maximum flow rate/Pcuff), voided volume and post-void residual were plotted by age and stratified by Newcastle Noninvasive Nomogram category.

Results: A total of 50,680 patients 20 to 100 years old (median age 66.0) met inclusion criteria. Median Pcuff was 144.3 cmH₂O and 60.8% of patients were categorized in the obstructed or high pressure/high flow Newcastle Noninvasive Nomogram quadrants. Median maximum flow rate was 10.9 ml per second and 55.8% had maximum flow rate greater than 10 ml per second. Median voided volume and post-void residual were 219.0 and 75.0 ml, respectively. All measures deteriorated with age (p <0.0001). Pcuff reflects the compensated/decompensated bladder function lifecycle. Values initially increased and reached peak pressure at age 62, then decreased by approximately 0.96 cmH₂O per year until age 90.

Conclusions: This study demonstrates that symptomatic patients enter urological practices at different urodynamic stages of bladder function and outlet obstruction, that Pcuff, maximum flow rate, voided volume, flow rate efficiency and post-void residual deteriorate with age, and that UroCuff is a sensitive evaluation of bladder performance.

Keywords: lower urinary tract symptoms; prostatic hyperplasia; urodynamics.