Preoperative factors predicting the outcome of a midurethal sling operation for treating women with mixed incontinence

Purpose: We wanted to investigate outcomes after midurethral sling (MUS) operations for treating women with mixed urinary incontinence (MUI) and we wanted to identify the factors for achieving a favorable outcome. Materials and Methods: The retrospective data was collected for 279 women with MUI and who underwent a MUS operation with at least 2 years follow up. The following measures were recorded before MUS: a disease-specific validated questionnaire, 1-hour pad tests, standardized stress tests and urodynamic study. The patients were divided as followed; a predominance of bothering symptoms (stress-predominance, urgency-predominance) and the presence of detrusor overactivity (DO). The patients with DO were further classified into the high detrusor pressure (HPDO) group and the low pressure (LPDO) group with a reference level of 15cmH₂O of maximum detusor pressure at which involuntary contraction occurred during filling cystometry. The patient's postoperative global impression of improvement, the Bristol Female Lower Urinary Tract Symptom (BFLUTS) score, improvement of stress incontinence (SUI) and urgency were analyzed. Results: The overall success rate of SUI was 96.4%. The predominance of bothering symptoms or the presence of DO did not influence the over all SUI success rate. In a subgroup of women with DO, those women with LPDO showed a significantly higher SUI cure rate than those with HPDO. Urge incontinence resolved in 176 (63.1%) and it improved in 60 (21.5%), while it was aggravated or it persisted in 43 (15.4%). Women with stress-predominant MUI, DO and LPDO experienced better resolution of urgency incontinence, an improved quality of life (QoL) and a higher global impression of improvement. Conclusions: Our results suggest that women with stress-predominant MUI and without DO or with LPDO are more likely to be cured of their urge urinary incontinence after a MUS operation for treating mixed urinary incontinence.