Can maximum urethral closure pressure (MUCP) be used to predict outcome of surgical treatment of stress urinary incontinence?

Aims: The outcome of surgery for stress urinary incontinence (SUI) can be unpredictable. Urethral pressure measurements, including measurement of maximum urethral closure pressure (MUCP) can form part of the investigation of women prior to SUI surgery and some studies have suggested that women with higher MUCP may have a better surgical outcome. This study aims to determine whether outcome of SUI surgery is related to pre-operative MUCP.

Methods: All patients undergoing colposuspension or TVT in a large European city between 1998 and 2002 were included. All women underwent pre-operative urodynamics, including measurement of urethral pressure profile; urodynamic data, including MUCP, were determined. Surgical outcome was measured using the ICIQ-FLUTS questionnaire, which was mailed to allow for a minimum follow-up period of 3 years. Surgical outcome was measured by assigning patients to one of three post-operative Stress Urinary Incontinence (SUI) groups. Group 1 (No incontinence), Group 2 (< 1 incontinence episode per day), Group 3 (> 1 incontinence episode per day). Independent statistical analysis was undertaken using STATA® software and a two-way ANOVA (Analysis of Variance) test to determine the relationship between pre-operative MUCP and post-operative SUI group.

Results: A total of 463 postal questionnaires were mailed, with a response rate of 62%, allowing for those who had died or moved away. Of the 285 responders, 218 had undergone colposuspension and 66 had a TVT. Median age, length of follow up and MUCP were 54 years (range 23-81), 77 months (range 47 to 107) and 45 cmH(2) O (range 5 to 105) respectively. Difference in MUCP between the two operation groups (colposuspension and TVT) was not significant (p > 0.19). No significant difference in preoperative MUCP was demonstrated between the three SUI groups, with mean MUCP in the three SUI groups of 50, 45 and 43 cmH(2) 0 respectively, confirming that patients with higher MUCP were not more likely to be in a lower post-operative SUI group (F(2, 237) = 3.42, p < 0.04).

Conclusion: Our data demonstrate that women with higher preoperative MUCP do not have a better surgical outcome following stress incontinence surgery.