Outcomes of urodynamic mixed urinary incontinence and urodynamic stress incontinence with urgency after mid-urethral sling surgery

Mixed urinary incontinence (MUI) is defined as symptomatic complaint of involuntary leakage associated with urgency and also with exertion, effort, sneezing or coughing. The paucity of research, especially on the surgical management of MUI, limits its best management.

This is a retrospective study to determine the outcomes of mixed urinary incontinence after mid-urethral sling surgery with two groups, urodynamic stress incontinence (USI) with urgency and urodynamic mixed urinary incontinence (MUI-UD; USI and detrusor overactivity [DO]).

Ninety women (USI + urgency group) with preoperative USI and urgency and no demonstrable DO/DOI attained an objective cure of 82.2%, whereas the remaining 67 (MUI-UD group) women with both USI and DO/DOI were reported to have an objective cure of only 55.2%. Subjective cures were 81.1% and 53.7% respectively. The type of incontinence surgery does not affect postoperative outcomes in either of the groups. Demographic factors identified to have a significant negative effect on cure rates were postmenopausal status (p = 0.005), prior hysterectomy (p = 0.028), pre-operative smaller blafdder capacity (p = 0.001), and a larger volume of pre-operative pad test (p = 0.028). A lower mid-urethral closure pressure (MUCP) was significant with post-operative failure of treatment with MUI-UD group (68.8 ± 36.2 cmH₂O vs 51.9 ± 24.7 cmH₂O; p = 0.033).

Although there is evidence for a good cure of the stress component of MUI, urodynamic investigation with its findings prior to management of MUI could have greater implications for selective patient centered counseling. Presence of DO or DOI on urodynamics resulted in poorer objective and subjective outcomes.