title: The long-term influence of body mass index on the success rate of mid-urethral sling surgery among women with stress urinary incontinence or stress-predominant mixed incontinence: comparisons between retropubic and transobturator approaches.
abstract: OBJECTIVE
  Mid-urethral sling (MUS) surgery for the treatment of urinary incontinence has been widespread since the introduction of tension-free vaginal tape in the mid-1990s. The majority of studies with short-term follow-up <2 years found no differences in the surgical outcomes according to body mass index (BMI). However, considering the chronic influence of obesity on pelvic floor musculature, it is cautiously speculated that higher BMI could increase stress on pelvic floor and sub-urethral tape, possibly decreasing the long-term success rate in the obese population. We aimed to compare the long-term effects of BMI on the outcomes of MUS between women with retropubic and transobturator approaches.
  
  
  METHODS
  We performed a retrospective analysis on 243 consecutive women who received MUS and were followed up for ≥36 months. The influence of BMI on the success rates was separately estimated and the factors for treatment failure were examined using logistic regression in either approach.
  
  
  RESULTS
  The mean follow-up was 58.4 months, and 30.5% were normal weight, 51.0% overweight, and 18.5% obese. Patients received either the retropubic (30.5%) or transobturator (69.5%) approach. The success rates (%) under the transobturator approach differed according to the BMI groups (94.3, 88.6, and 78.6, respectively; P = 0.037) while those under the retropubic approach were not different according to the BMI groups. However, in multivariate models, only the presence of preoperative mixed urinary incontinence (MUI) was proven to be the risk factor for treatment failure in the transobturator approach (OR 6.39, P = 0.003). The percent of subjects with MUI was higher in obese women than in non-obese women with the transobturator approach.
  
  
  CONCLUSIONS
  BMI was not independently associated with failures in either approach. Higher success rates in women with lower BMI in the transobturator approach were attributed to the lower percent of preoperative MUI in those with lower BMI.
authors.affiliation: Department of Urology, Seoul National University Bundang Hospital, Seongnam, Korea.
authors.forename: Seong Jin
authors.initials: SJ
authors.lastname: Jeong
authors.affiliation: Department of Urology, Seoul National University Bundang Hospital, Seongnam, Korea.
authors.forename: Han Sol
authors.initials: HS
authors.lastname: Lee
authors.affiliation: Department of Urology, Seoul National University Bundang Hospital, Seongnam, Korea.
authors.forename: Jeong Keun
authors.initials: JK
authors.lastname: Lee
authors.affiliation: Department of Urology, Seoul National University Bundang Hospital, Seongnam, Korea.
authors.forename: Jin Woo
authors.initials: JW
authors.lastname: Jeong
authors.affiliation: Department of Urology, Seoul National University Bundang Hospital, Seongnam, Korea.
authors.forename: Sang Cheol
authors.initials: SC
authors.lastname: Lee
authors.affiliation: Department of Urology, Kangwon National University Hospital, Chuncheon, Korea.
authors.forename: Jeong Hyun
authors.initials: JH
authors.lastname: Kim
authors.affiliation: Department of Urology, Seoul National University Bundang Hospital, Seongnam, Korea.
authors.forename: Sung Kyu
authors.initials: SK
authors.lastname: Hong
authors.affiliation: Department of Urology, Seoul National University Bundang Hospital, Seongnam, Korea.
authors.forename: Seok-Soo
authors.initials: SS
authors.lastname: Byun
authors.affiliation: Department of Urology, Seoul National University Bundang Hospital, Seongnam, Korea.
authors.forename: Sang Eun
authors.initials: SE
authors.lastname: Lee
mesh_terms: D015992:Body Mass Index; D005260:Female; D006801:Humans; D016015:Logistic Models; D008875:Middle Aged; D009765:Obesity / Q000150:complications*; D012189:Retrospective Studies; D012307:Risk Factors; D053825:Suburethral Slings / Q000706:statistics & numerical data*; D016896:Treatment Outcome; D014549:Urinary Incontinence / Q000601:surgery*; D013520:Urologic Surgical Procedures / Q000295:instrumentation* / Q000379:methods