Long-term effectiveness of sacral nerve stimulation for refractory urge incontinence

Objectives: To evaluate the long-term efficacy of sacral nerve stimulation for refractory urinary urge incontinence. Study Design and Methods: Urge incontinent patients qualified for surgical implantation of a neurostimulator system after trial screening with percuta neous test stimulation. Surgical implantation of the InteStim System (Medtr onic Inc., Minneapolis, Minn., USA) was performed in cases where a >50% red uction in incontinence symptoms was documented during the 3- to 7-day test stimulation period. The InterStim System consists of an implantable pulse g enerator, a transforamenally placed quadripolar lead, and an extension that connects these two devices for unilateral stimulation of the S3 or S4 sacr al nerve. Efficacy for 96 implanted patients was based on urinary symptom c hanges as quantified in voiding diaries collected at baseline and annually after surgical implantation. Results: As compared to baseline, the group of 96 implanted patients demons trated significant reductions in urge incontinent symptoms at an average of 30.8 +/- 14.8 (range 12-60) months with respect to the number of urge inco ntinent episodes per day, severity of leaking, and the number of absorbent pads/diapers replaced per day due to incontinence (all p<0.0001, respective ly). Gender, pretreatment variables, and age were not found to be relevant factors that affected these results. 11 of the 96 patients underwent device explant due to lack of efficacy, pain or bowel dysfunction. These data wer e conservatively included in the efficacy results. No permanent injuries as sociated with the devices or therapy were reported. Conclusion: Sacral nerve stimulation is an effective treatment for refracto ry urge incontinence with sustained long-term benefit through an average of 30.8 months. Copyright (C) 2001 S. Karger AG, Basel.