Reoperation for urinary incontinence: a nationwide cohort study, 1998-2007

BACKGROUND: The synthetic midurethral slings were introduced in the 1990s and were rapidly replaced the Burch colposuspension as the gold standard treatment for urinary incontinence. It has been reported that the retropubic midurethral tape has an objective and subjective cure rate of 85% at 5 years of follow-up, but the rate of reoperation after retropubic midurethral tape at the long-term follow-up is less well described. The existing literature specifies an overall lifetime rate of reoperation of about 8-9% after an initial operation for urinary incontinence. There are, however, conflicting statements about the risk of reoperation after specific surgical procedures for urinary incontinence. OBJECTIVE: The objective of the study was to describe the cumulative incidence of reoperation within a 5 year period after different types of surgical procedures for urinary incontinence based on a nationwide population. STUDY DESIGN: We used the Danish National Patient Registry to identify women who had surgery for urinary incontinence from 1998 through 2007 and the outcome was a reoperation within 5 years. Kaplan-Meier curves were used to estimate the rate of reoperation for 6 types of surgery for urinary incontinence (retropubic midurethral tape, transobturator tape, urethral injection therapy, Burch colposuspension, pubovaginal slings, and miscellaneous operations). Cox proportional hazard models were used to estimate the hazard ratio (HR) with 95% confidence intervals (CIs), adjusted for factors suspected to be associated with reoperation. RESULTS: A total of 8671 women (mean age, 56.1 years, range 6.7-93.7 years) underwent surgical treatment for urinary incontinence. Among these women, 5820 (67%) received a synthetic midurethral sling at baseline. The cumulative incidence of reoperation after any surgical treatment for urinary incontinence was 10%. The lowest rate of reoperation was observed among women having pubovaginal slings (6%), retropubic midurethral tape (6%) and Burch colposuspension (6%) followed by transobturator tape (9%), and miscellaneous operations (12%), whereas the highest observed risk was for urethral injection therapy (44%). In a Cox proportional hazard model that adjusted for age, department volume, and calendar effect, the transobturator tape carried a 2-fold higher risk of reoperation (HR, 2.1; 95% CI, 1.5-2.9), and urethral injection therapy carried a 12 fold-higher risk (HR, 11.5; 95% CI, 9.3-14.3) compared with retropubic midurethral tape. CONCLUSION: This nationwide cohort study provides physicians with a representative evaluation of the rate of reoperations after surgical procedures for urinary incontinence. Pubovaginal slings, Burch colposuspension, and retropubic midurethral tape had a similar risk of reoperation (6%). Women who were operated with transobturator tape had a significantly higher risk of reoperation compared with retropubic midurethral tape.