Botulinum toxin A injection for the treatment of neurogenic detrusor overactivity secondary to spinal cord injury: Multi-institutional experience in Japan

Abstract

Objectives: To examine the efficacy and safety of onabotulinumtoxinA (Botox) injection into the bladder wall for the treatment of neurogenic detrusor overactivity secondary to spinal cord injury in Japanese patients. Methods: We enrolled Japanese spinal cord injury patients with cystometrically confirmed neurogenic detrusor overactivity who experienced urinary incontinence at least once a week either because they were refractory to anticholinergics or had to discontinue treatment because of adverse events. Patients received 200 units of onabotulinumtoxinA injected into the bladder wall after a 2-week washout of anticholinergics, and urodynamic variables were assessed before and 1month after injection. Catheterization and urinary incontinence data, as well as International Consultation on Incontinence Questionnaire - Short Form scores, were assessed before injection and every month thereafter until the cessation of treatment effects. Results: The study enrolled 19 patients (13 men, six women, age range 22-67years). One month after injection, the mean number of urinary incontinence episodes decreased from 4.3 to 1.5times/day (P=0.004), and the maximum cystometric capacity increased from 100mL to 296mL (P=0.0004). The rate of effective cases whose daily urinary incontinence frequency was decreased to less than 50% was 74%. The duration of efficacy without anticholinergic medication ranged from 3 to 12months (median 8.5months). Clinically significant adverse events were not observed. Conclusions: The present findings show the efficacy and tolerability of onabotulinumtoxin A injection for the treatment of neurogenic detrusor overactivity in Japanese spinal cord injury patients.