Retropubic vs Transobturator Midurethral Slings May Be Equally Effective for Stress Incontinence
By Laurie Barclay, MD
Medscape Medical News
June 8, 2010 — Retropubic or transobturator midurethral slings may be equally effective for stress incontinence, according to the results of a large, multicenter, randomized equivalence trial reported in the June 3 issue of the New England Journal of Medicine.
"Midurethral slings are increasingly used for the treatment of stress incontinence, but there are limited data comparing types of slings and associated complications," write Holly E. Richter, PhD, MD, from the University of Alabama at Birmingham, and colleagues from the Urinary Incontinence Treatment Network. "The transobturator approach was developed to minimize the potential for bladder and bowel injuries associated with the retropubic sling, since the sling is passed through the obturator foramen, avoiding the pelvic organs in the retropubic space."
The objective of the study was to compare outcomes with retropubic vs transobturator midurethral slings in women with stress incontinence. The main study endpoint was treatment success at 12 months, defined by objective as well as by subjective criteria. Objective criteria were a negative stress test result, a negative pad test result, and no subsequent treatment, and subjective criteria were self-reported absence of symptoms, no leakage episodes recorded, and no subsequent treatment. Equivalence was predetermined as a difference of no greater than ±12 percentage points.
Of 597 women randomly assigned, 565 (94.6%) completed the 12-month evaluation. Objectively defined treatment success occurred in 80.8% of the retropubic-sling group and in 77.7% of the transobturator-sling group (3.0 percentage-point difference; 95% confidence interval [CI], ?3.6 to 9.6). For subjectively defined success, the rates were 62.2% and 55.8%, respectively (6.4 percentage-point difference; 95% CI, ?1.6 to 14.3).
None of those who received transobturator slings vs 2.7% of those who received retropubic slings experienced voiding dysfunction requiring surgery (P = .004) Rates of neurologic symptoms were 4.0% and 9.4%, respectively (P = .01). The groups were statistically similar in postoperative urge incontinence, satisfaction with the outcome of the procedure, and quality of life.
"The 12-month rates of objectively assessed success of treatment for stress incontinence with the retropubic and transobturator approaches met the prespecified criteria for equivalence; the rates of subjectively assessed success were similar between groups but did not meet the criteria for equivalence," the study authors write. "Differences in the complications associated with the two procedures should be discussed with patients who are considering surgical treatment for incontinence."
In an accompanying editorial, Rebecca G. Rogers, MD, from the University of New Mexico Health Sciences Center in Albuquerque, notes limitations of follow-up for only 1 year and possible lack of generalizability to less highly skilled surgeons.
"The rationale for the introduction of new surgical procedures is often based on short-term outcomes, whereas patients want both short-term and long-term results," Dr. Rogers writes. "Up to a third of women who have surgery for stress incontinence undergo a second procedure during their lifetime, and data regarding the long-term effectiveness and equivalence of these two procedures are critical to decision making.... What may change [because of this study] is how patients are counseled regarding the benefits and harms associated with the surgery, allowing surgical choices to better match a patient's goals and wishes, as well as the surgeon's abilities."
The National Institute of Diabetes and Digestive and Kidney Diseases and the National Institute of Child Health and Human Development supported this study. Disclosure forms provided by the study authors and by Dr. Rogers are available with the full text of this article at the NEJM Web site .
