Long-Term Outcomes Of Synthetic Mid-Urethral Slings (Mesh Tapes) In Surgical Treatment Of Stress Urinary Incontinence In Women – A Long-term Follow-Up Of The SIMS RCT

Research Question: What is the long-term safety, effectiveness and cost effectiveness of synthetic mid-urethral slings (MUS - mesh tapes) in surgical treatment of stress urinary incontinence (SUI)?

Background: Urinary incontinence is a common and disabling condition affecting women of all ages but primarily over 40s. SUI is the most common type of UI and often requires surgery. MUS (mesh-based procedure) have been the mainstay of surgical treatment for SUI for the last 2 decades.

In the last 5years, there has been a growing public concern on the lack of robust, industry independent evidence on MUS long-term effectiveness and safety. The urgent need for this evidence has been highlighted by the recent NICE guideline (NG123), Cochrane review and the 2020 public inquiry report “First Do No Harm”.

Aim: To determine the long-term safety, effectiveness and cost effectiveness of MUS (mesh) in surgical treatment of SUI in women while comparing single incision mini-slings (SIMS) versus standard mid-urethral slings (SMUS).

Methods: Long-term follow-up of the SIMS trial participants using annual questionnaires up to 10-years follow-up. Primary outcome is patient overall assessment of the outcome of the procedure using PGI-I validated questionnaire (success defined as Very much/Much Improved). The primary economic outcome will be incremental cost per quality adjusted life years (QALY) gained at 10-years.

Secondary outcomes include composite outcome of success on PGI-I and no further continence surgery; late onset (>3-years) adverse events (AEs); reoperation rates for SUI and/ or treatment of AEs; impact of the procedure on women’s QoL and sexual function. We will use patients’ medical records to ascertain type of further surgery received / admission for AEs.

We will use routinely collected dataset on hospital admissions and procedures (NHS Digital and eDRIS) to enhance the quality of our data including non-responders to follow-up questionnaires. We have also included an embedded qualitative study using semi-structured interviews that will explore: patient experiences/ satisfaction with treatment and impact on QoL and; patient perceptions of decision process and decision outcomes (e.g. decisional regret and decisional conflict). Analysis will use intention to treat but we will also use a secondary per protocol analysis.

Study Timeline: Start June 2021. Months 1-4 study initiation, Months 1-78 complete annual follow-up up-to 10-years; Months 43-50 the 7-year analysis, write-up and publication, including qualitative component; Months: 75 and 82: routinely collected dataset reports; Months: 79-82: final analysis including health economic analysis, and write-up.

Impact and Dissemination: The SIMS long-term results are expected to have a significant impact due to the ongoing highly publicised public debate on the use of mesh in women with SUI worldwide. It will allow us to provide robust long-term data on the use of mesh to treat SUI in women which are currently not available. It will also provide crucial evidence whether the technology of using significantly less mesh volume in SIMS (50% less than SMUS) has comparable longevity and safety compared to standard length MUS.

If proven this could change clinical practice towards safer use of mesh procedures. The results of the study will be included in updates of NICE and EAU guidelines, which directly influence practice in the UK and worldwide respectively.