Suburethral sling operations for urinary incontinence in women

Suburethral slings are surgical operations used to treat women with urinary incontinence. They were originally designed for recurrent stress incontinence, but have also been used recently for primary cases.

To determine the effects of suburethral slings on stress or mixed urinary incontinence in comparison with other management options.

We searched the Cochrane Incontinence Group's trials register, The National Research Register and the reference lists of relevant articles. We hand searched the proceedings of the Brazilian Congress of Urology from 1991 to 1999, inclusive. Date of most recent search: January 2000.

Randomised or quasi-randomised trials that included suburethral slings for the treatment of urinary incontinence.

Both reviewers independently extracted data from included trials onto a standard form and assessed trial methodological quality. The data abstracted were relevant to predetermined outcome measures. Where appropriate, a summary statistic was calculated: a relative risk for dichotomous data and a weighted mean difference for continuous data.

Five trials were identified including 206 women - 126 treated with suburethral slings and 80 with other procedures. Three compared suburethral slings with open abdominal retropubic suspensions (Burch/Marshall-Marchetti-Krantz) and one compared suburethral slings with needle suspension (Stamey). In the fifth trial, different types of suburethral sling were compared with each other. Six types of slings were included (Teflon, polytetrafluoroethylene, Goretex, porcine dermis, lyophilized dura mater and rectus fascia). There were no comparisons of suburethral sling with anterior repair, laparoscopic retropubic suspension, peri-urethral injections, artificial sphincters or conservative management. There is one ongoing trial with Tension-free Vaginal Tape (TVT) versus Burch colposuspension, results expected in August 2000. For each outcome data were available only from individual trials. There were no detectable differences in terms of voiding dysfunction, urge incontinence or detrusor instability between suburethral slings and abdominal or needle suspensions, but the data were few and the confidence intervals wide. More peri-operative complications were reported after suburethral slings than after needle suspension (9/10 vs 2/10; RR 4.5, 95% CI 1.3 to 15.8), and length of stay was longer after sling operations than after abdominal or needle suspension. In the trial which compared autologous (rectus fascia) with synthetic (Goretex) slings, 11/32 vs 2/16 women had not improved after a year (RR 2.75, 95% CI 0.69 to 10.95), but fewer had complications (0/32 vs 5/16; RR 0.05, 95% CI 0 to 0.8). Two women in the second group had late sling erosion of the urethra requiring removal of the Goretex, although their incontinence remained cured.

There were few data available to compare suburethral sling operations with other surgical management (abdominal and needle suspension, or different types of slings). In general, the quality of trials was poor with no clear method of randomisation, small numbers of women studied, short follow-up and scanty information on outcome measures. There is not enough evidence on which to judge whether suburethral slings are better or worse than other surgical or non surgical managements.