ADJUSTABLE SINGLE-INCISION MINI SLINGS VERSUS STANDARD TENSION FREE MID URETHRAL SLINGS IN THE SURGICAL MANAGEMENT OF FEMALE STRESS URINARY INCONTINENCE: A PRAGMATIC MULTICENTRE NON INFERIORITY RANDOMISED CONTROL TRIAL - THE SIMS TRIAL.

Adjustable Anchored Single-Incision Mini-Slings Versus Standard Tension-Free Mid-Urethral Slings in the Surgical Management Of Female Stress Urinary Incontinence; A Pragmatic Multicentre NonÐInferiority Randomised Controlled Trial: The SIMS Trial.

Urinary incontinence in women is a major issue for the NHS and for society, with the number affected and cost of treatment posing a significant burden of healthcare both now, and in the future with an ageing population. A large UK study has shown that a third of community dwelling women aged 40 and over had significant urinary symptoms, with 12% experiencing UI weekly. Female Stress Urinary Incontinence (SUI) is the involuntary loss of urine through exercise, laughing, sneezing or coughing. It is the most common form of incontinence in premenopausal women and can have a significant negative effect on women's quality of life. It usually results from damage to the support of the urethra (the tube from the bladder to outside) during childbirth although symptoms may occur many years later. Primary non-surgical treatments seek to increase the support of the urethra with pelvic floor exercises but if these fail then surgery is the only alternative. In the most common surgical procedure, tension-free standard mid urethral slings (SMUS), a synthetic mesh (tape) is placed under the urethra to add support by creating a sub-urethral hammock. SMUS are done under general anaesthesia or deep sedation and the tape is held in place by friction to the surrounding muscles and ligaments but eventually becomes embedded-in by in-growth of body tissues; therefore women are instructed to limit their activities for an average of 4-weeks until the tape is reasonably integrated. Rare but serious complications can arise from the blind insertion of SMUS into the pelvis (such as bowel or major blood vessels injury) and occasionally thigh pain can occur for weeks and months after the operation. An alternative procedure known as adjustable anchored single-incision mini-sling (SIMS) is designed to have advantages over tension-free SMUS in that it avoids the blind insertion trajectory into the pelvic cavity or the thigh muscles while maintaining the concept of the hammock support to the urethra. The avoidance of the pelvic trajectory eliminates the risk of serious injuries such as bowel injury while avoidance of the thigh muscles trajectory led to substantive reduction in pain during and after insertion of the sling enabling this procedure to be done under pure local anaesthesia. In our preliminary study, we have shown the acceptability (70%) and feasibility (98%) of this relatively new procedure to be done under pure local anaesthesia i.e. without any sedation with high levels of women satisfaction at 6 & 12 months follow-up. One key advantage of the new procedure is that the tape is kept in place by a strong and secure anchoring mechanism to the pelvic side-walls and therefore women may not have to restrict their activities after surgery. This feature, together with avoidance of general anaesthesia and/or sedation, allows for rapid recovery after surgery; earlier return to normal activities, both of which would be potentially reflected in better improvement in women's quality of life. Subsequently, we undertook a small comparative study comparing the new procedure (SIMS) to the standard surgery (SMUS) and this has shown SIMS to have fewer complications during the operation, shorter hospital stay, less pain after insertion (performed under pure local anaesthetic). Interestingly, women in our preliminary studies have resumed their professional activities significantly earlier than those who had the standard procedures, which if replicated on all patients will undoubtedly have economic benefits to both women themselves and the wider community. In summary the new procedure has potential advantage of being a truly ambulatory procedure with shorter hospital stay and earlier recovery with economic benefits to both the NHS & the wider community. However before this new procedure can be widely implemented in clinical practice it needs robust assessment to ensure (a) it is as effective as the current standard procedures and (b)to prove the above potential health & economic benefits. We propose to randomise 650 women from 25 UK centres to receive either a SIMS or SMUS procedure. Participation in the research will be voluntary and women will be provided with full information about the research. We do not believe that there are any specific risks of harm or adverse events involved in participating in this research. However, we shall provide information about supports that will be available to participants and what to do in the event of adverse events. We will follow their progress over the first 12 months, measuring potential benefits, risks and costs associated with each procedure and compare these outcomes and will be able then to present/ publish our first and primary report. However, as the durability of the successful outcomes of these procedures is quite important as it is not good enough to be successful at 12 month then the condition deteriorate/ recur and need another operation soon. Therefore we plan to follow-up women recruited in this RCT for 3 years to assess if this new technology lives up for its potentials compared to the standard procedures. This study RCT will therefore inform decision making for patients with SUI, their surgeons and the relevant policy makers. The study team is comprised of consultant surgeons working in collaboration with experienced health services researchers and patient/consumer representatives, all of whom have a track record of delivering large multi-centre randomised trials. If our preliminary results are confirmed in this definitive large trial we anticipate that SIMS will become the first choice surgical treatment for most women with stress urinary incontinence.