Midurethal slings found superior to mini-slings in stress urinary incontinence

Glasgow, Scotland-Female stress urinary incontinence treatment with single-incision mini-slings (SIMS) yields significantly lower cure rates and higher risk of repeat surgery compared with standard midurethral slings (MUS), findings from a systematic literature review and meta-analysis of effectiveness and safety outcomes indicate.

The project included data from 758 women enrolled in nine published, randomized, controlled trials comparing SIMS with standard midurethral slings (retropubic and transobutrator tension-free vaginal tape procedures). Follow-up ranged from 6 to 12 months.

The results, reported at the International Continence Society annual meeting in Glasgow, Scotland, showed SIMS had advantages compared with MUS for significantly reducing operative time (~8.5 minutes), pain on the first postoperative day (1.74 points based on a 10-point scale), and postoperative groin pain (relative risk=0.18). However, SIMS were associated with significantly lower cure rates in analyses of both patient-reported and objective outcomes (relative risk=0.83 and 0.85, respectively), and the difference persisted in sensitivity analyses excluding studies of unclear quality. In addition, women treated with SIMS had a significantly higher risk of repeat continence surgery (~6.7-fold), tape erosion (3.9-fold), and de novo urge incontinence (2-fold) than their counterparts undergoing MUS procedures.

"Systematic review and meta-analysis is the cornerstone for evidence-based medicine, and this is the first meta-analysis of randomized controlled trials to assess the efficacy and complications of SIMS versus MUS. Its results confirm published reports questioning the efficacy of SIMS, and the finding may be explained by the relatively short trajectory and less substantial fixation of SIMS compared to MUS."

The study was a collaborative project that included researchers from Sheffield Teaching Hospitals and NHS Grampian, the United Kingdom. The literature search covered the period from 1996 to January 2011, and identified studies published in any language comparing SIMS and MUS. A total of 533 relevant articles were identified, abstracts of 124 articles were reviewed, and 26 were selected for full-text assessment. In the nine papers that were finally included, the TVT SECUR (Ethicon Inc., Somerville, NJ) was the SIMS used in the majority of studies (67%).

Seven studies reported subjective cure/improvement outcomes and six included objective efficacy data. Only two studies included usable data on quality of life, and the meta-analysis showed no significant difference between surgical groups for this endpoint. There was no difference in hospital stay between study groups or in wound infection, hematoma, urinary tract infection and hematuria, solid organ injury, postoperative voiding difficulty, wound infection, or dyspareunia. No studies reported on sexual function or health care costs.

Authors acknowledge study limitations

The authors acknowledged their analysis had limitations that were mostly related to the low number and quality of the studies included. Furthermore, none of the included randomized, controlled trials evaluated the new adjustable SIMS that are believed to have addressed the limitations of earlier SIMS, Dr. Abdel-Fattah said.

However, the researchers also highlighted its strengths.

"Our study was conducted through a peer-reviewed protocol with no language restrictions, we obtained further details from authors of seven papers, and the meta-analysis was performed in accordance with the preferred reporting items for systematic review statements using statistical methods that addressed some of the potential limitations," Dr. Abdel-Fattah told Urology Times.

"We hope to update this analysis in a few years when, hopefully, data from more RCTs and from longer follow-up will be available."

Dr. Abdel-Fattah is a clinical consultant for American Medical Systems, Bard, and Coloplast.