Very Low, Real-Time Rate of Urinary Retention after Intradetrusor Botox<sup>&reg</sup> for Non-Neurogenic Overactive Bladder

Abstract

Introduction: According to the most recent AUA/SUFU guidelines, intradetrusor onabotulinumtoxinA (BTN/A) is a standard, evidence strength grade B, third line treatment option for refractory non-neurogenic overactive bladder (OAB). Urinary retention is the most common clinically significant reported side effect ranging from 5.4% to 43% in previous studies. The aim of this study was to investigate the real-time rate of urinary retention in patients treated with BTN/A for refractory non-neurogenic OAB in a multi-institutional study. Methods: Retrospective chart review identified 71 patients who were treated with 100U BTN/A for refractory non-neurogenic OAB from August 2011 to July 2015 at two institutions. Using a flexible cystoscope, 100U Botox&reg reconstituted with 10 ml normal saline was administered. Injections of 1 ml (10 units/ mL) were administered in 10 evenly distributed sites sparing the trigone. Pre and post BTN/A post-void residuals (PVR) were reviewed. Urinary retention was defined as PVR > 200 mL requiring clean intermittent catheterization (CIC). Results: After exclusion, the study group consisted of 66 patients with a mean age of 67 years and 30% were men. Mean pre and post-procedural PVR were 14.06 mL and 69.21 mL. Eight patients (12.12%) were noted to have elevated PVR > 200 mL post injection however only one patient (female) required initiation of CIC. The rate of urinary retention was 1.5% (N = 1). There was no correlation with age, history of previous radiation, diabetes or prior use of a neuromodulator device. Conclusions: To the best of our knowledge, this is the first study to demonstrate a very low risk of real-time urinary retention rates in appropriately selected patients treated with BTN/A for refractory non-neurogenic OAB outside of a clinical trial setting.