Background
Female stress urinary incontinence (SUI) greatly affects quality of life. The midurethal sling (MUS) procedure has been widely accepted as the standard of care treatment for SUI, although there is little information regarding patients' subjective reports of symptom improvement.

Objectives
The objective of this study was to identify clinical and demographic characteristics that predict subjective symptom improvement following MUS procedures in women with SUI.

Materials and Methods
The study design was retrospective cohort. Subjects included women who underwent MUS between 2006 and 2008, returned mailed surveys and met our predefined inclusion criteria. Pre-operative data included demographics, prior surgery, co-morbid diseases, urodynamics and concomitant reconstructive surgery. Subjective improvement was measured by score improvement on the UIQ-7, UDI-6, the UDI stress subscale and Question 3 of the UDI, "Do you experience urine leakage related to physical activity, coughing, or sneezing?"

Results
The mean age of the study sample was 57 years, parity was 2.5 and BMI was 28. Subjects with lower MUCP demonstrated more improvement on the UIQ-7. ΔUDI-6 stress subscale scores were more sensitive to symptom change than either the ΔUDI-6 or ΔUIQ-7. Older, menopausal subjects with urethral hypermobility and concomitant vaginal suspension showed less improvement than subjects without these characteristics. After controlling for urethral straining angle, PVR, menopause and time out from surgery, older age and concomitant vaginal suspension were associated with persistent post-op symptoms on the UDI-6 Question 3 and age remained the only variable associated with persistent symptoms on the UDI-6 stress subscale.

Conclusion
Concurrent vaginal suspension and advancing age were risk factors for persistent symptoms following MUS procedures in patients with SUI. Symptoms may recur after 24 post-operative months. Clinicians are encouraged to provide additional preoperative counseling to those women who are at greatest risk for persistent symptoms.