Prospective validation of a novel visual analogue uroflowmetry score (VAUS) in 1000 men with lower urinary tract symptoms (LUTS)

Abstract

Introduction and aims: Family physicians are limited by lack of tools to monitor benign prostate hyperplasia. VAUS provides a cost-effective, easily administered non-invasive tool. Our primary aim was to validate VAUS correlation with uroflowmetry measured maximal flow rate (Q_max), voided volume and International Prostate Symptom Scores (IPSS) symptom scores. Secondary aim was to study how the VAUS fared at predicting poor flow (Q_max < 10 ml/s) compared to age, voided volume and IPSS. Tertiary aim was to predict the best VAUS as a cutoff for poor flow.

Methods: After IRB approval, 1000 patients were prospectively recruited. They had VAUS, uroflowmetry and IPSS performed. VAUS is a novel five-point visual analogue scoring of urine flow, with one being the weakest and five the strongest. Data were analysed using SPSS where spearman's correlation coefficient and logistic regression analysis were performed looking for significance. Receiver operating curves (ROC) curves were used to identify best VAUS cutoff.

Results: 1000 patients were studied with mean age of 68.99 (50-95). VAUS showed good correlation with Q_maxp < 0.001, voided volume p = 0.006 and IPSS p <0.001. On multivariate analysis both VAUS and voided volume predicted poor flow significantly with p value of<0.001 and p =0.001, respectively. On ROC analysis VAUS of 2.5 was identified as best value for predicting poor flow with p value <0.001.

Conclusion: VAUS is a validated tool for monitoring of lower urinary tract symptoms in our patients showing significant correlation with uroflowmetry, voided volume and IPSS.

Keywords: Benign enlargement of prostate; International prostate symptom score; Symptom score; Visual prostate.