Simple and reliable predictor of urinary continence after radical prostatectomy: serial measurement of urine loss ratio after catheter removal.

Objectives: To evaluate urine loss ratio after catheter removal as a predictive factor of urinary continence after radical prostatectomy.

Methods: A total of 190 patients who had undergone retropubic radical prostatectomy were evaluated. Urine loss ratio was measured using the 24-h pad test during 7 consecutive days after removal of urethral catheters. Continence rates at 1, 3, 6 and 12 months after operation were evaluated with the urinary function domain of the University of California, Los Angeles Prostate Cancer Index. The desirable urine loss ratio for continent condition at 12 months after the operation was calculated. As desirable target urine loss ratio continence at 12 months was determined by using logistic analysis.

Results: Continence rates of all patients at 1, 3, 6 and 12 months after surgery were 13%, 37.8%, 58.9%, and 85.8%, respectively. Continence rates of patients who achieved ≤1% of urine loss ratio within 7 days or ≤5% urine loss ratio within 3 days after catheter removal was 100% at 12 months. Logistic regression analysis proved these urine loss ratio values were significant predictors of continence at 12 months.

Conclusions: Urine loss ratio after catheter removal within 7 days is a significant determinant of urinary continence after radical prostatectomy. This parameter could have clinical usefulness to estimate future recovery of urinary continence.