Impact of age on outcomes of midurethral sling procedures in women

Single-incision mini-slings versus standard synthetic mid-urethral slings for surgical treatment of stress urinary incontinence in women: The SIMS RCT

BACKGROUND

Stress urinary incontinence is the most common type of urinary incontinence in premenopausal women. Until recently, synthetic mid-urethral slings (mesh/tape) were the standard surgical treatment, if conservative management failed. Adjustable anchored single-incision mini-slings are newer, use less mesh and may reduce perioperative morbidity, but it is unclear how their success rates and safety compare with those of standard tension-free mid-urethral slings.

OBJECTIVE

The objective was to compare tension-free standard mid-urethral slings with adjustable anchored single-incision mini-slings among women with stress urinary incontinence requiring surgical intervention, in terms of patient-reported effectiveness, health-related quality of life, safety and cost-effectiveness.

DESIGN

This was a pragmatic non-inferiority randomised controlled trial. Allocation was by remote web-based randomisation (1 : 1 ratio).

SETTING

The trial was set in 21 UK hospitals.

PARTICIPANTS

Participants were women aged ≥ 18 years with predominant stress urinary incontinence, undergoing a mid-urethral sling procedure.

INTERVENTIONS

Single-incision mini-slings, compared with standard mid-urethral slings.

MAIN OUTCOME MEASURES

The primary outcome was patient-reported success rates on the Patient Global Impression of Improvement scale at 15 months post randomisation (≈ 1 year post surgery), with success defined as outcomes of 'very much improved' or 'much improved'. The primary economic outcome was incremental cost per quality-adjusted life-year gained. Secondary outcomes were adverse events, impact on other urinary symptoms, quality of life and sexual function.

RESULTS

A total of 600 participants were randomised. At 15 months post randomisation, adjustable anchored single-incision mini-slings were non-inferior to tension-free standard mid-urethral slings at the 10% margin for the primary outcome [single-incision mini-sling 79% (212/268) vs. standard mid-urethral sling 76% (189/250), risk difference 4.6, 95% confidence interval -2.7 to 11.8; p non-inferiority < 0.001]. Similarly, at 3 years' follow-up, patient-reported success rates in the single-incision mini-sling group were non-inferior to those of the standard mid-urethral sling group at the 10% margin [single-incision mini-sling 72% (177/246) vs. standard mid-urethral sling 67% (157/235), risk difference 5.7, 95% confidence interval -1.3 to 12.8; p non-inferiority < 0.001]. Tape/mesh exposure rates were higher for single-incision mini-sling participants, with 3.3% (9/276) [compared with 1.9% (5/261) in the standard mid-urethral sling group] reporting tape exposure over the 3 years of follow-up. The rate of groin/thigh pain was slightly higher in the single-incision mini-sling group at 15 months [single-incision mini-sling 15% (41/276) vs. standard mid-urethral sling 12% (31/261), risk difference 3.0%, 95% confidence interval -1.1% to 7.1%]; however, by 3 years, the rate of pain was slightly higher among the standard mid-urethral sling participants [single-incision mini-sling 14% (39/276) vs. standard mid-urethral sling 15% (39/261), risk difference -0.8, 95% confidence interval -4.1 to 2.5]. At the 3-year follow-up, quality of life and sexual function outcomes were similar in both groups: for the International Consultation on Incontinence Questionnaire Lower Urinary Tract Symptoms Quality of Life, the mean difference in scores was -1.1 (95% confidence interval -3.1 to 0.8; p = 0.24), and for the Pelvic Organ Prolapse/Urinary Incontinence Sexual Questionnaire, International Urogynecological Association-Revised, it was 0 (95% confidence interval -0.1, 0.1; p = 0.92). However, more women in the single-incision mini-sling group reported dyspareunia [12% (17/145), compared with 4.8% (7/145) in the standard mid-urethral sling group, risk difference 7.0%, 95% confidence interval 1.9% to 12.1%]. The base-case economics results showed no difference in costs (-£6, 95% confidence interval -£228 to £208) or quality-adjusted life-years (0.005, 95% confidence interval -0.068 to 0.073) between the groups. There is a 56% probability that single-incision mini-slings will be considered cost-effective at the £20,000 willingness-to-pay threshold value for a quality-adjusted life-year.

LIMITATIONS

Follow-up data beyond 3 years post randomisation are not available to inform longer-term safety and cost-effectiveness.

CONCLUSIONS

Single-incision mini-slings were non-inferior to standard mid-urethral slings in patient-reported success rates at up to 3 years' follow-up.

FUTURE WORK

Success rates, adverse events, retreatment rates, symptoms, and quality-of-life scores at 10 years' follow-up will help inform long-term effectiveness.

TRIAL REGISTRATION

This trial was registered as ISRCTN93264234.

FUNDING

This project was funded by the National Institute for Health and Care Research (NIHR) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 26, No. 47. See the NIHR Journals Library website for further project information.

Predictors of cure and overactive bladder syndrome after a mid-urethral sling procedure in women with stress urinary incontinence

OBJECTIVES

To determine predictive factors for the cure of stress urinary incontinence (SUI) or persisting or de novo overactive bladder syndrome (OAB) after a mid-urethral sling procedure (MUS) for women with SUI, especially for menopausal women.

STUDY DESIGN

All women who had consecutively received MUS for SUI between January 2008 and July 2019 in a tertiary referral center were reviewed.

MAIN OUTCOME MEASURES

Multivariable Cox proportional hazards model or logistic regression analysis was used to assess the predictors of cure and persisting or de novo OAB after MUS.

RESULTS

A total of 385 women had undergone MUS, of whom 265 (68.8%) were menopausal. The multivariable Cox proportional hazards model revealed that age (hazard ratio = 1.04), and preoperative detrusor overactivity (hazard ratio = 2.26) were independent predictors of persisting/recurrent SUI. Among the 216 women with preoperative OAB, 109 (50.5%) experienced resolution of their OAB after MUS; and among 169 women without preoperative OAB, twenty-five (14.8%) women developed de novo OAB after MUS (p < 0.0001). Preoperative OAB (hazard ratio = 3.97), small voided volume (hazard ratio = 0.83), and preoperative detrusor overactivity (hazard ratio = 1.62) were predictors of postoperative OAB. In addition, six (1.6%) women had mesh extrusion. Parity (odds ratio = 2.08) was the sole predictor of mesh extrusion. Menopause (hazard ratio = 1.69) was a predictor of postoperative OAB in the univariate analysis. However, menopause was not a predictor of cure or OAB in the multivariable analysis.

CONCLUSIONS

Age and preoperative detrusor overactivity were independent predictors of persisting/recurrent SUI. In addition, preoperative OAB, small voided volume, and preoperative detrusor overactivity were predictors of postoperative OAB. These findings could serve as a guide for preoperative consultation for MUS.

A retrospective analysis of perioperative complications associated with retropubic tension-free vaginal tape in 960 women

Purpose

The purpose is to analyse perioperative complications associated with the retropubic tension-free vaginal tape (TVT) procedure and their management.

Methods

This retrospective, monocentric cohort study included 960 women after retropubic TVT procedure performed by one surgeon from 2011 to 2016. Complications were identified up to 6 weeks after the procedure, divided into specific and general complications and classified based on the Clavien–Dindo (CD) Classification. A visit 6 weeks after the surgical procedure was attended by all patients.

Results

77 complications, of which 74 occurred postoperatively and 3 intraoperatively, affecting 72 (7.5%) out of 960 women. Urinary retention and voiding problems were the most common complication. The mean age of women suffering complications was 3.4 years higher in comparison to the mean age of women without complications (p = 0.036). The Body Mass Index (BMI) of the group of women with perioperative complications had an average BMI which was 0.5 kg/m² lower than the average BMI of the women without complications. 22 (12.8%) out of 172 women with recurrent stress incontinence had postoperative complications, of which 21 were related to the TVT.

Conclusion

The retropubic TVT is a surgical procedure associated with a low number of perioperative complications, even in the group of elderly and overweight women, as well as in cases of recurrent stress incontinence.

Spatial distribution of smooth muscle tissue in the female pelvic floor and surrounding the urethra and vagina

Data regarding urethral supporting structures are insufficient for understanding the mechanism of stress urinary incontinence. Whether smooth muscle fibers contribute to urethral support and pelvic floor support structures is unclear. This study aimed to clarify the histological structures and spatial distributions of smooth muscle tissues surrounding the urethra and vagina. Using cadaveric specimens, macroscopic anatomical and histological evaluations were conducted. Six female cadavers were used for macroscopic observations. Ten female cadavers were used for histological observations. Three pelvises were cut in a plane vertical to the urethra, and the other pelvises were cut in a plane parallel to the urethra and vagina to observe tissues surrounding the urethra and vagina. The major tissue component around the proper muscle layer of the urethra was smooth muscle tissue, which mediated among the urethra, pubis, and levator ani. Smooth muscle tissues laterally extended the smooth muscle fibers, both superiorly and inferiorly toward the levator ani, with a few fibers inserted in the levator ani. Smooth muscle was found between the urethral walls and pubic bones. Smooth muscle may contribute to the mechanism of pelvic floor support.