THE EFFECT OF POSTOPERATIVE WEIGHT CHANGE ON OUTCOMES FOLLOWING MIDURETHRAL SLING FOR STRESS URINARY INCONTINENCE

Abstract

Objective: To examine the effect of postoperative weight change on outcomes 12 months after mid-urethral sling (MUS) for stress urinary incontinence (SUI). Materials and methods: This is a secondary analysis of two multicenter randomized controlled trials of women undergoing MUS: The TOMUS trial and the ESTEEM trial. Data was obtained from the NIH Data and Specimen Hub (DASH) database and NIDDK Central Repository. Subjects were categorized into three cohorts based on % change in body weight from baseline to 12 months after MUS: 1) ‘weight gain’ (? 5% increase) 2) ‘weight loss’ (? 5% decrease) and 3) ‘weight stable’ (? 5% change). Outcomes were assessed 12 months postoperatively. The primary outcome was SUI success defined as no SUI episodes on 3-day bladder diary. Secondary outcomes included SUI symptoms and bother on UDI-6 questionnaire, frequency of SUI episodes on bladder diary and patient global impression of improvement (PGI-I) with success defined as “much better/very much better”. The subset of patients with MUI preoperatively were analyzed for changes in urge incontinence episodes 12 months postoperatively. One-way analysis of variance was used to compare differences between cohorts for continuous variables. For dichotomous variables, logistic regression was used to assess differences using stable weight group as the reference. Multivariable analyses adjusted for age, smoking status and BMI. Results: 918 subjects were included, 64% underwent RP and 36% underwent TO sling. There were no significant differences in demographics or perioperative adverse events between the cohorts except for a higher rate of smokers and higher baseline BMI in the ‘weight loss’ cohort. At 12 months postoperative, 635 (70%) subjects’ weight remained stable, 144 (15%) gained weight and 139 (15%) lost weight with all cohorts reporting high SUI success (81%, 79% and 77%, respectively). There were no significant differences between the cohorts in SUI success (p 0.6), SUI episodes postoperative (p 0.8), SUI symptoms and bother on UDI-6 (p 0.6, p 0.6 respectively), and success on PGI-I (84%, 87%, 885; p 0.3) (Table1). In the subset of 372 subjects with MUI, the ‘weight loss’ group had significantly greater improvement in urge urinary incontinence (UUI) episodes on 3-day bladder diary (-1.9, -1.4, -2.7; p 0.006). Conclusions Postoperative weight change did not affect SUI symptoms at 12 months after MUS, but subjects with MUI who lost ? 5% body weight over 12 months had a significantly greater decrease in UUI episodes on 3-day diary. Weight loss following MUS surgery may improve UUI.