Retropubic or transobturator mid-urethral slings for intrinsic sphincter deficiency-related stress urinary incontinence in women: a systematic review and meta-analysis.

INTRODUCTION AND HYPOTHESIS: Stress urinary incontinence is a common problem affecting 12-46% of women. A cohort of women have a more severe form of stress urinary incontinence usually due to intrinsic urethral sphincter deficiency that has traditionally resulted in lower success rates with standard treatment modalities. We aim to address the question of whether transobturator sling insertion is more effective than retropubic sling insertion in the treatment of intrinsic sphincter deficiency-related stress urinary incontinence in women.

METHODS: We searched MEDLINE, CINAHL, CENTRAL, journals, and major conferences (up to 30 June 2014). All randomised controlled trials in women with stress urinary incontinence or mixed urinary incontinence with associated intrinsic sphincter deficiency who underwent a retropubic or transobturator mid-urethral sling operation were included in this meta-analysis. The Cochrane risk of bias tool and the GRADE system were used to assess the quality of evidence.

RESULTS: Fifty-five randomised controlled trials compared transobturator and retropubic mid-urethral slings. Twelve trials included women with intrinsic sphincter deficiency, but only 8 trials (399 women) reported data specifically for this cohort. There was a statistically significant difference in short- and medium-term (≤5 years) subjective cure rates, with the number of women reporting a cure in the transobturator group at 150 out of 199 and the retropubic group at 171 out of 200. This gives a 12% relative risk reduction in achieving cure with the transobturator route (RR 0.88, 95% CI 0.80 to 0.96, I(2) = 0%, moderate quality evidence [GRADE]). Objective cure was reported by five trials of 324 women and showed no statistically significant difference between the two groups, with a rate of 110 out of 159 in the transobturator group and 126 out of 165 in the retropubic group (RR 0.90, 95% CI 0.79 to 1.03). Post-operative voiding dysfunction and de novo urgency or urgency urinary incontinence in the two treatment groups showed no significant difference. The need to undergo repeat incontinence surgery in the long term (≥5 years) was higher with the transobturator route (RR 14.4, 95% CI 1.95 to 106, 147 women).

CONCLUSIONS: Mid-urethral slings are effective in treating women with intrinsic sphincter deficiency-associated stress urinary incontinence. The retropubic route resulted in higher subjective cure rates compared with transobturator routes. Both routes improved the overall quality of life.