Urodynamic assessment of bladder and urethral function among men with lower urinary tract symptoms after radical prostatectomy: A comparison between men with and without urinary incontinence

Purpose We compared bladder and urethral functions following radical prostatectomy (RP) between men with and without urinary incontinence (UI), using a large-scale database from SNU-experts-of-urodynamics-leading (SEOUL) Study Group. Materials and Methods Since July 2004, we have prospectively collected data on urodynamics from 303 patients with lower urinary tract symptoms (LUTS) following RP at three affiliated hospitals of SEOUL Study Group. After excluding 35 patients with neurogenic abnormality, pelvic irradiation after surgery, or a history of surgery on the lower urinary tract, 268 men were evaluated. We compared the urodynamic findings between men who had LUTS with UI (postprostatectomy incontinence [PPI] group) and those who had LUTS without UI (non-PPI group). Results The mean age at an urodynamic study was 68.2 years. Overall, a reduced bladder compliance (≤20 mL/cmH2O) was shown in 27.2% of patients; and 31.3% patients had idiopathic detrusor overactivity. The patients in the PPI group were older (p=0.001) at an urodynamic study and had a lower maximum urethral closure pressure (MUCP) (p<0.001), as compared with those in the non-PPI group. Bladder capacity and detrusor pressure during voiding were also significantly lower in the PPI group. In the logistic regression, only MUCP and maximum cystometric capacity were identified as the related factor with the presence of PPI. Conclusions In our study, significant number of patients with LUTS following RP showed a reduced bladder compliance and detrusor overactivity. PPI is associated with both impairment of the urethral closuring mechanism and bladder storage dysfunction.