The role of preoperative testing on outcomes after sling surgery for stress urinary incontinence

In this study we analyzed Medicare claims data to measure the effect of preoperative urodynamics and cystoscopy on outcomes after sling surgery.

We analyzed 1999 to 2001 Medicare claims data on a 5% national random sample of beneficiaries. Women who underwent sling procedures between July 1, 1999 and December 31, 2000 were identified on the basis of the presence of CPT-4 code 57288 (sling operation for stress incontinence). Subjects were tracked for 6 months before surgery to identify type of preoperative studies performed (urodynamics and cystoscopy) and for 12 months after surgery to assess short-term complications.

Of 1,356 subjects 24.8% underwent preoperative cystoscopy and 27.4% underwent preoperative urodynamic testing. In postoperative year 1, 32.4% of subjects underwent cystoscopy and 30.5% underwent urodynamics. Patients who underwent preoperative urodynamics were more likely to be newly diagnosed with urge incontinence after surgery (21.9% vs 12.7%, p <0.0001). Those who underwent preoperative cystoscopy were significantly more likely to be diagnosed with (9.4% vs 6.1%, p <0.043) or treated for (10.6% vs 7.2%, p <0.047) outlet obstruction postoperatively than those who did not. Multivariate analysis revealed that subjects who underwent preoperative urodynamics were significantly less likely to undergo postoperative urodynamics than those who did not (OR 0.34, 95% CI 0.24-0.48).

Our findings of worse outcomes among women who underwent preoperative testing may be due in part to case selection. Our finding that women who underwent preoperative urodynamics were only a third as likely to undergo postoperative urodynamics as those who did not supports the use of urodynamics in the preoperative setting. However, the true effect of urodynamics on sling outcomes remains controversial.