Factors Influencing Postoperative Overactive Bladder after Adjustable Trans-Obturator Male System Implantation for Male Stress Incontinence following Prostatectomy

Abstract

We aimed to determine the risk factors for postoperative overactive bladder (OAB) in patients treated with an adjustable trans-obturator male system (ATOMS) for stress incontinence after radical treatment of prostate cancer. A prospective study was performed on 56 patients implanted with an ATOMS for PPI. Clinical and urodynamic information was recorded before and after ATOMS implantation. We built a multivariate model to find out the clinical and urodynamic factors that independently influenced postoperative OAB and the prognostic factors that influenced the efficacy of medical treatment of OAB. We found that the clinical risk factors were the preoperative intensity of urinary incontinence (number of daily pads used and amount of urinary leakage), International Consultation on Incontinence Questionnaire (ICIQ) score, postoperative number of ATOMS adjustments, final cushion volume, and incontinence cure. The urodynamic data associated with OAB were cystometric bladder capacity, voided volume, volume at initial involuntary contraction (IC), maximum flow rate, bladder contractility index (BCI), and urethral resistance (URA). The prognostic factors for the efficacy of oral treatment of OAB were the volume at the first IC (direct relationship) and the maximum abdominal voiding pressure (inverse relationship). The multivariate model showed that the independent clinical risk factors were the daily pad count before the implantation and the ICIQ score at baseline and after treatment. The independent urodynamic data were the volume at the first IC (inverse relationship) and the URA value (direct relationship). Both predictive factors of treatment efficacy were found to be independent. Detrusor overactivity plays an important role in postoperative OAB, although other urodynamic and clinical factors such as the degree of urethral resistance and abdominal strength may influence this condition.