Greater risk of re-operation with TOT vs. TVT

The authors evaluated cumulative incidence of re-operation after various surgical procedures for urinary incontinence within 5 years.

Montreal-Data from a population-based, historical cohort study presented at the International Continence Society annual meeting in Montreal suggest some synthetic midurethral sling (SMUS) surgeries lead to greater rates of re-operation than other SMUS surgeries.

Specifically, investigators from Denmark found transobturator tape (TOT) sling surgeries, which were introduced in that country in 2003, were linked to a two-fold increased risk of re-operation when compared to tension-free vaginal tape (TVT) sling surgery, (HR: 2:1; CI: 1.5-2.9).

"More patients with severe urinary incontinence derive benefit from TVT as a surgical procedure than TOT," said first author Margrethe Foss Hansen, MD, of the University of Southern Denmark, Odense, in an interview with Urology Times. She explained that the goal of the study was to assess the cumulative incidence of re-operation after various surgical procedures for urinary incontinence within 5 years.

Dr. Foss Hansen and co-investigators found the overall cumulative risk of re-operation within 5 years of stress urinary incontinence surgery was 10.2% and looked at the rates of re-operation for various types of surgery including TVT, TOT, urethral injection therapy, and Burch colposuspension.

The study cohort consisted of all women recorded in the Danish National Patient Registry who had undergone surgical treatment for UI from 1998 through 2007 and who had no surgery for urinary incontinence 2 years prior to enrollment in the study. An initial 9,819 were included but 1,148 were excluded, leaving a cohort of 8,671 with a mean age of 56.1 years. Of the cohort of 8,671, 5,820 (67%) had SMUSs at baseline. A total of 888 women overall were re-operated in a 5-year period.

Next: Majority of re-operations took place within first 2 years of primary surgery

Investigators found the median time to re-operation was 1 year for all sling surgeries, 2 years for Burch colposuspension, and 6 months for urethral injection surgery. They also found the majority of re-operations took place within the first 2 years of the primary surgery and then levelled off in the remaining 3 years.

Dr. Foss Hansen cited a study from 2009 that was updated in 2015 (Cochrane Database Syst Rev, Oct. 7, 2009, and July 1, 2015), which found no significant difference between TVT and TOT, but she stressed that that study had only a 12-month follow-up period and only included 746 women.

"The follow-up was shorter, and we think we have more power to detect a difference (in the re-operation rate) between the two procedures than those investigators did," said Dr. Foss Hansen.

She noted that, ideally, data should be derived from randomized, controlled trials.

"It is costly to do those trials. We recognize that the retrospective nature of this study is a limitation," she said.

Dr. Foss Hansen and colleagues adjusted their results for possible confounders like age, department volume, and calendar effect, but they did not analyze other potential risk factors linked to re-operation such as body mass index, severity of symptoms of urinary incontinence, and skills of the surgeon.

Still, based on these data, TVT is more effective than TOT and would avoid a re-operation of a patient with incontinence, said Dr. Foss Hansen.