University of Massachusetts Medical School, Worcester, Massachusetts Correspondence: Stephen B. Young, MD, Division of Urogynecology, Department of Obstetrics & Gynecology, 55 Lake Avenue North, Worcester, MA 01655.
OBJECTIVES: To determine if typical pre-operative clinical measures and validated questionnaires can consistently predict the risk of subjective failure following midurethral sling (MUS) procedures MATERIALS AND METHODS: This prospective cohort included 157 of 550 women who underwent MUS between 2006 and 2008, returned mailed PFDI/PFIQ surveys and met inclusion criteria. Pre-operative data included urodynamics, age, weight, menopausal status, prior incontinence and prolapse surgery, co-morbid diseases and concomitant reconstructive surgery. Subjective improvement was defined as achievement of the minimally important difference (MID) for the UDI-6, UIQ-7 and UDI stress subscale (Barber, AJOG 2009). RESULTS: Overall the mean age of the study sample was 57 years, parity 2.5, BMI 28 with a mean of 21 months of subjective follow-up. 23% had prior prolapse surgery and 5% had prior incontinence surgery. Following multivariate analysis, preoperative intrinsic sphincter deficiency (ISD) remained significantly associated with a lower symptom improvement on the UDI (P = 0.03) and failure to achieve the MID-UDI (P = 0.03). Subjects with high preoperative UIQ scores were more likely to achieve the MID on the UIQ postoperatively (P < 0.0001). On the UDI stress subscale, menopausal status was associated with achievement of the MID (P = 0.02) although advancing age predicted failure to achieve the MID (P = 0.02). Mean preoperative urodynamic parameters include MUCP of 43.1 cm H2O and LPP of 86.5 cm H2O. Twenty percent had straining Q-tip angles less than 30 degrees. MUCP ≤20 cm H2O and LPP ≤60 cm H2O identified ISD equally (12.9%). The MUS was performed with anterior repair in 40.8% and with apical suspension in 34.4% and the cohort equally represented the retropubic and transobturator routes. The mean decrease in the UDI-6, UIQ-7 and UDI stress subscale scores was −34.0 (±29.3, range −87.5 to 33.3), −19.1 (±30.5, range −100 to 61.9) and −46.6 (±42.8, −100 to 75), respectively. Univariate analysis performed for each outcome measure showed that age, BMI, cystocele Grade/Stage, duration of follow-up, ISD and concomitant apical suspension were associated with less symptom improvement whereas the Q-tip angle, preoperative UIQ score and concomitant anterior repair predicted greater symptom improvement. CONCLUSION: Preoperative diagnosis of ISD was a consistent predictor of less subjective improvement after MUS in this cohort. We did not find the expected relationship between failure to achieve the MID and other clinical measures that have previously been associated with poor MUS outcome. Our results suggest that further studies are needed to effectively correlate preoperative indicators and subjective outcomes following MUS.
