Researchers in Taiwan have identified risk factors for adverse events (AEs) from intravesical injections of botulinum toxin A (BoNTA) for refractory idiopathic detrusor overactivity (IDO).
Hann-Chorng Kuo, MD, of Buddhist Tzu Chi General Hospital and Tzu Chi University in Hualien, and colleagues studied 217 patients with this condition who receive their first intravesical BoNTA injection. They found that male gender was associated with a significant 9.2 times increased odds of experiencing acute urinary retention (AUR). Patients with a baseline postvoid residual volume (PVR) of 10 mL or more had a significant 9.9 times increased odds of AUR and 2.9 times increased odds of straining to void, according to findings published online in European Urology. In addition, receiving a BoNTA dose greater than 100 U was associated with a significant twofold increased odds of straining to void.
Urinary tract infections (UTIs) occurred significantly more frequently in women than men (22% vs. 7%). “After BoNTA injection, half of the women in this study had to void by abdominal straining and had large PVR, both of which are risk factors for UTI in women,” the authors noted.
Of the 217 patients in the study, 144 (66.3%) reported successful outcomes (96 dry, 48 moderately improved), which was determined based on patient perception of their bladder condition at three months. Another 36 subjects (16.6%) reported mild improvement and 37 reported treatment failure.
During follow-up, specific AEs occurred in 113 patients (52.1%). AUR developed in 18 patients (8.3%) and 101 patients (46.5%) reported straining to void.