Characteristics Associated With Treatment Failure 1 Year After Midurethral Sling in Women With Mixed Urinary Incontinence

Mixed urinary incontinence, including both stress urinary incontinence (SUI) and urgency urinary incontinence (UUI), occurs in up to 50% of women with urinary incontinence. Mixed incontinence is often considered more severe and more difficult to treat than either urinary condition alone. Clinical guidelines that recommended treating SUI and UUI separately were largely based on older, currently uncommon surgical procedures and limited data. Guidelines have cautioned that surgery for the SUI component may worsen the urgency component. The ESTEEM (Effects of Surgical Treatment Enhanced with Exercise for Mixed Urinary Incontinence) trial was a multicenter network study designed to determine among a population of women with mixed urinary incontinence whether use of perioperative behavioral and pelvic floor muscle therapy combined with midurethral sling surgery (combined treatment) would improve urinary symptoms at 12 months compared with sling alone. The trial data demonstrated that 85% of patients were overall "much better" or "very much better" after midurethral sling with or without behavioral and pelvic floor muscle therapy, with symptomatic movement in UUI symptoms. Worsening urgency at 12 months was reported by less than 5% of women.Most prior midurethral sling studies have focused on populations with pure SUI or stress-predominantmixed incontinence. Risk factors in these populations identified for sling failure were concurrent prolapse surgery, preoperative anticholinergic medication use, increasing age, and urgency, as well as baseline mixed incontinence symptoms. Perioperative counseling of women with mixed urinary incontinence who are considering midurethral sling would be assisted by better understanding risk of factors for persistent urinary symptoms, either SUI or UUI.The current study is a planned secondary analysis of data from women from the original ESTEEM trial. The aim of this study was to identify demographic and clinical variables associated with urinary symptom treatment failure at 12 months among women with mixed incontinence undergoing midurethral sling. Participants were 403 women, 21 years or older, with mixed incontinence who reported moderately to severely bothersome SUI and UUI symptoms for at least 3 months and had at least 1 documented SUI and 1 UUI episode in a 3-day bladder diary. Unmasked patients were randomized 1:1 (stratified by clinical site and UUI severity) to combined treatment (midurethral sling and behavioral and pelvic floor muscle therapy) or midurethral sling alone.Participants completed questionnaires, including the Urogenital Distress Inventory (UDI) and 3- day bladder diaries at baseline and at 3, 6, and 12 months postoperatively. Overall treatment failure was defined as meeting criteria for subjective or objective failure or both based on persistent urinary symptoms and need for additional treatment after surgery. The minimal clinically important difference for the UDI total score was 26.1 points; subjective failure was defined as not meeting this score. Women with objective failure were those not achieving 70% improvement on mean incontinence episodes of any type per day or having undergone any additional treatment for urinary symptoms at 12 months. Bivariate analyses were performed to identify potential clinical, demographic, and urodynamic variables associated with treatment failure based on comparisons at the P < 0.2 level. To identify independent variables at 12 months, logistic regression models were constructed for each outcome (overall, subjective, and objective failure). Potential interaction effects involving treatment group were assessed.Multivariable logistic regression showed that factors associated with overall treatment failure included previous use of overactive bladder medication (odds ratio [OR], 2.19; adjusted OR [aOR], 1.89; 95% confidence interval [CI], 1.10-3.25; P = 0.02), higher body mass index, (OR, 1.29; aOR 1.27; 95% CI, 1.03-1.57; P = 0.03 for each 5-point increase), detrusor overactivity on cystometrogram (OR, 2.25; aOR, 2.72; 95% CI, 1.53-4.84; P < 0.001), and Valsalva leak point pressure less than 60 cm H2O (OR, 1.96; aOR, 3.13; 95% CI, 1.65-5.94; P < 0.001). Women with worse UDI urgency scores were at increased risk of treatment failure in the midurethral sling-alone group. Type of sling (retropubic vs transobturator) was not associated with treatment failure.These data show certain clinical and urodynamic variables associated with treatment failure after midurethral sling among a population of women with mixed urinary incontinence. The subpopulation of women with more severe urgency symptoms at baseline is likely to benefit from combined treatment of sling and perioperative pelvic floor muscle training. This information can help clinicians when counseling women with mixed incontinence who are considering sling surgery.