A novel tool to assess the risk of urinary incontinence after nerve-sparing radical prostatectomy

What's known on the subject? and What does the study add? Urinary incontinence is one of the most important morbidities after radical prostatectomy that has detrimental effect on the postoperative quality of life. The present study provides an accurate and dynamic multivariable risk stratification tool that predicts the postoperative urinary incontinence risk after radical prostatectomy based on patient-related as well as surgeon-related variables. Objective To develop a multivariable risk classification tool to estimate postoperative urinary incontinence (UI) risk as UI represents one of the most disabling surgical sequelae after radical prostatectomy (RP). Patients and Methods We evaluated 1311 patients treated with nerve-sparing RP between 2006 and 2010 at our institution. Regression tree analysis was used to stratify patients according to their postoperative UI risk. KaplanMeier curve estimates were used to assess the UI rate in the novel UI-risk groups. The discrimination of the novel tool was measured with the area under the curve method. Results At 3, 6 and 12 months, the UI rates were 44%, 26% and 12%, respectively. Regression tree analysis stratified patients into high risk (International Index of Erectile Function Erectile Function domain [IIEF-EF] = 110), intermediate risk (IIEF-EF > 10 and age 65 years), low risk (IIEF-EF > 10, age < 65 years and body mass index [BMI] 25kg/m2) and very low risk (IIEF-EF > 10, age < 65 years and BMI < 25kg/m2) groups. The 3-month UI rates in these groups were 37%, 43%, 45% and 48%, respectively. The 6-month UI rates were 19%, 23%, 29% and 34%, respectively. The 12-month UI rates were 7%, 13%, 14% and 15%, respectively (log-rank P < 0.001). The area under the curve was 71%, 70% and 68% at 3, 6 and 12 months, respectively. Conclusions We developed the first risk classification tool that predicts patients at high risk of UI after RP. These consisted mainly of individuals who were impotent before RP, elderly and/or overweight. This tool can be used for patient counselling.