REFRACTORY URINARY URGE INCONTINENCE AFTER STRESS INCONTINENCE SURGERY: CAN IT BE MANAGED WITH SACRAL NEUROMODULATION?

N.D. Sherman, C.L. Amundsen, G.D. Webster

Duke University Medical Center, Durham, NC

OBJECTIVE:  Following stress incontinence surgery, the incidence of de novo and worsening preexisting urinary urge incontinence (UUI) is between 10% and 40%, respectively. Behavioral and pharmacologic therapy may not optimally manage UUI.   Our objective was to evaluate the response of sacral neuromodulation (InterStim Continence Control System) in patients with refractory UUI post SUI surgery and determine whether any factors are associated with a positive response.  

MATERIALS AND METHODS: This is a retrospective study of such women treated between October 2000 and September 2004. Urethral obstruction was excluded as a cause for de novo or worsening urge incontinence.  All completed an urogynecologic questionnaire, focused pelvic exam, 3 day bladder diary, 24 hour pad weight, cystoscopy, and video-urodynamic study.  A test stimulation period, via a percutaneous electrode (PNE) or a 2 stage approach, was performed for 5-7 days, during which time a bladder diary and 24 hour pad weight were completed. A positive response was considered as a >50% improvement in urge incontinent episodes or pad weight. InterStim responders and non-responders were compared for pre test stimulation demographics, urodynamic findings and incontinence parameters. Data was analyzed using chi-square analysis.

RESULTS:  Twenty-two of the 34 women (65%) responded to the test stimulation and underwent permanent sacral neuromodulation implantation. There was no statistically significant difference between the responders and non-responders with respect to age, technique used for the  test stimulation, type of stress incontinence surgery, episodes of leakage/day, maximum flow rate and detrusor pressure at maximum flow rate, and the type of detrusor overactivity on urodynamics.  Independent variables for a positive response to sacral neuromodulation included age < 55 (p.01),  < 4 years since SUI surgery (p .01),  pre-stimulation 24-hour pad weight <400 mL (p .02) and pelvic floor musculature grade >2/9 (p .04). 

CONCLUSIONS:  Sacral neuromodulation appears to be comparably successful in patients with refractory urinary urge incontinence after a SUI surgery to those with idiopathic urge incontinence.  Our study showed that a younger age, recent SUI surgery, and milder urge incontinent symptoms may lead to a better response.   The type of stress incontinence surgery and urodynamics did not help predict which patients would respond.  Sacral neuromodulation should be considered for those patients suffering from refractory UUI after SUI surgery.

Key Words: neuromodulation, InterStim, urinary incontinence

Disclosure – Nothing to disclose.