Repeat versus primary slings in patients with intrinsic sphincter deficiency

Abstract

Our goal was to compare outcomes of repeat vs. primary synthetic slings in patients with stress urinary incontinence (SUI) with intrinsic sphincter deficiency (ISD). We reviewed patients who underwent a sling for SUI with ISD from 2003 to 2010. The patients were divided into two groups according to whether they underwent primary or repeat sling. Surgical success was defined as no incontinence and no reintervention (i.e., urethral bulking) during follow-up. Statistical analysis included the unpaired t test, Wilcoxon rank sums test, chi-squared/Fisher's exact tests, and logistic regression to identify risk factors associated with failure. Six hundred and thirty-seven patients with ISD underwent a sling procedure at our institution; 557 (87 %) a primary sling and 80 (13 %) a repeat sling. Patient demographics were similar. Preoperatively, patients with recurrent SUI reported more subjective bother. Mean follow-up was 66.5 weeks (24-374). Success was achieved in 81 % of primary compared with 55 % of repeat slings (p<0.0001). Repeat patients were 3.4 times more likely to fail surgery [odds ratio (OR) =3.43, 95 % confidence interval (CI) 2.1-5.6]. Additionally 30 % of the repeat group underwent urethral bulking postoperatively compared with 8.6 % in the primary group (OR=4.4, 95 % CI 2.5-7.7). Prior incontinence procedures, a positive supine stress test, and transobturator sling were independent risk factors for failure. Among the types of slings placed (transobturator, retropubic, tensioned pubovaginal), pubovaginal slings were most successful (OR=2.7, 95 % CI 1.4-5.2). In women with ISD, repeat slings are associated with lower success rates compared with primary slings. Pubovaginal slings resulted in the highest success rate compared with both transobturator and retropubic slings.