Evaluating Success Rates After Artificial Urinary Sphincter Placement: A Comparison of Clinical Definitions

Abstract

To assess success rates of primary artificial urinary sphincter (AUS) implantation using various objective, subjective, or retreatment definitions. We identified 309 male patients who underwent primary AUS placement at the Mayo Clinic from 2010 to 2016. Of those, 214 had not undergone repeat surgery, were sent a mailed survey, and 148 of 214 (69.2%) responded. Eleven definitions of success were evaluated among responders. Associations between the definitions and patient-reported success were assessed via logistic regression and c-statistic. Treatment success rates were highly variable depending on the definition used (14.8%-86.7%). Median follow-up was 24 months (interquartile range [IQR] 8, 40), during which 72% did not undergo reoperation. Among survey respondents, 87% felt at least "much better," and 47% reported surgery was "very successful." Roughly 15% reported zero pad use. Patient-reported success was most strongly associated with the Patient Global Impression of Improvement (PGI-I) score (odds ratio [OR] 0.07, 95% confidence interval [CI] 0.02-0.19; P <.0001; c = 0.88). The largest difference in Michigan Incontinence Symptom Index (M-ISI) score between treatment successes and failures was noted when success was defined by PGI-I as well (success group M-ISI 11 vs failure group M-ISI 24.15; OR 0.48, 95% CI 0.37-0.63; P <.0001; c = 0.97). In terms of pad count, use of a security pad or less was most closely associated with patient-reported success (OR 0.18, 95% CI 0.10-0.35; P <.0001; c = 0.75). The "success rate" after primary AUS implantation varies widely depending on the definition used. Although most patients report that surgery was beneficial, zero pad count was less common. Among definitions evaluated, the PGI-I had the strongest association with patients' evaluation of surgical success.