Mid-urethral slings revolutionized the surgical management of stress urinary incontinence in women and both the retropubic and the transobturator approach have been widely used. Some advantages have been noted for both techniques, mainly with regard to short-term outcomes. However, evidence concerning the long-term performance of mid-urethral slings as a whole is scarce. The objective of this register-based cohort study is to evaluate the efficacy and safety of mid-urethral slings 10 years after the application and compare the two main surgical techniques used; the retropubic (TVT) and the transobturator (TVT-O/TOT) approach.

Women operated upon with a mid-urethral sling between 2006 and 2010 were identified using the Swedish National Quality Register of Gynecological Surgery. Data was also collected from the register and analyzed, including information from a 1-year follow-up postoperatively. The eligible women were contacted by letter at minimum 10 years after the index operation and were invited to answer to questionnaires regarding urinary incontinence and its impact on quality-of-life parameters (UDI-6, IIQ-7), pelvic floor and sexual function (PISQ-12), impression of improvement as well as questions regarding possible sling-related complications and reoperations.

Out of the 4108 women contacted, 2421 women responded (response rate of 58.9%).The participating women had a mean age of 64 years. TVT was used in 1562 women and TVT-O/TOT in 859 women. In total, stress urinary incontinence (SUI) was reported by 36.7% of the participants, urgency by 47.6%, urgency urinary incontinence (UUI) by 57.8% and urinary retention by 29.7% of the women at the 10-year follow-up. Of all women having received a mid-urethral sling, 91.6% reported being better or much better after 1 year and 79.2% after 10 years compared to their condition preoperatively. SUI, urgency and UUI at 10 years were significantly more common among women having received a TVT-O/TOT compared to TVT (p<0.005), whereas no significant difference was recorded between the two methods regarding urinary retention. The same findings were recorded when the analyses were adjusted for age, BMI, parity, diabetes, ASA-group, type of incontinence and previous incontinence surgery. Women in the TVT group also reported significantly lower UDI-6 scores (16.7 vs. 22.2, p<0.001) and higher levels of improvement at the 10-year follow-up (80.8% vs. 76.3%, p=0.004) even though there was no significant difference between the two groups at the 1-year follow-up (92.2% vs. 90.6%, p=0.2). No difference was detected between TVT and TVT-O/TOT regarding IIQ-7 or PISQ-12 scores at 10 years. The percentage of women reporting any sling-related symptoms at any time during the 10 years postoperatively was 24.8% while 17.7% reported persisting symptoms at the 10-year follow-up. The most common sling-related symptom as stated by the participants was urinary retention (11.2%). Mesh exposure was reported by 2.0% of the participants and reoperation because of the tape by 5.6%. No difference was recorded between women operated with TVT or TVT-O/TOT regarding sling-related complications or reoperations at the 10-year follow-up. Repeated operation for urinary incontinence after the first sling procedure was reported by 6.9% of the participating women, significantly more in the TVT-O/TOT group (9.1% vs. 5.6% in the TVT group, p=0.002). Logistic regression analysis revealed that BMI, type of incontinence, previous incontinence surgery and urinary retention preoperatively were the most important predictors with significant predictive value for SUI, UUI and impression of improvement at 10-year follow-up, whereas urinary retention preoperatively and complications under the first year postoperatively were significant predictors for persisting symptoms due to complications and urinary retention at 10 years. SUI at 1-year follow-up was strongly associated with SUI at 10-year follow-up, whereas no outcome was associated with weight gain.

The percentage of women reporting no stress urinary incontinence and those reporting improvement at 10-year follow-up reveal adequate long-term performance of the mid-urethral slings. Despite a small decline in efficacy, mid-urethral slings present sustainable long-term results with acceptable complications profile as suggested by the participants’ overall impression of improvement. The retropubic technique appears to be more favorable considering its efficacy with its superiority over the transobturator approach growing through the 10-year follow-up period. Interestingly, no difference was observed between the two techniques concerning complications or reoperations. Urinary retention preoperatively presents a strong predictive value for both the efficacy and the safety of mid-urethral slings at 10 years, while postoperatively urinary retention constitutes the most common sling-related symptom.

Mid-urethral slings present good results for the treatment of stress urinary incontinence and tolerable complications profile in a ten year perspective. In this long-term follow-up setting, the retropubic technique displays higher efficacy than the transobturator approach with no noticeable difference regarding safety.