Botulinum Toxin A for Idiopathic Detrusor Overactivity

Abstract

Introduction: This prospective study aims to evaluate botulinum toxin type A (BTX-A, Botox®) as a treatment for idiopathic detrusor overactivity (IDO) for patients with symptoms of overactive bladder (OAB). Materials and Methods: Nineteen patients with IDO were treated with intradetrusal injection of 200 units of BTX-A under cystoscopic guidance. There were 10 males and 9 females, with a mean age of 60 years (range, 38 to 87). Subjective responses were measured using the International Prostate Symptom Score and quality of life (QOL) score, as well as incontinent episodes, functional capacity and voiding intervals obtained from the voiding diary. They were recorded prior to, and at 6 weeks, 3, 6 and 9 months after BTX-A injections. Urodynamic studies were performed between 6 weeks to 3 months post-treatment. Results: There was statistically significant improvement in subjective parameters at 3 months post-treatment involving QOL (P = 0.002), incontinence episodes (P = 0.004), functional capacity (P = 0.01) and voiding interval (P <0.001). Reflex volume was significantly increased (P= 0.003), and maximal detrusal pressure (P = 0.001) as well as leak volume (P = 0.013) were significantly decreased during follow-up. Results of a gender-based subgroup analysis reveal that BTX-A may be more efficacious in females. Observed side effects included a patient who needed to perform CISC for about 3 months, a patient who had gross haematuria needed bladder washout and 3 patients who required treatments for urinary tract infection. Conclusion: Overall BTX-A, which is well received by most patients, has become a very important part of the armamentarium for the treatment of IDO. Key words: Botox®, Idiopathic detrusor overactivity, Overactive bladder, Urodynamics