Objective: The aim of the present study was to assess the effects of onabotulinumtoxinA injection for refractory non-neurogenic overactive bladder (OAB) for 12 months.
Methods: For patients with persistent urgency urinary incontinence (UUI) more than once a week despite taking anti-cholinergic agents or incapability to continue the agents because of adverse effects, 100 units of onabotulinumtoxinA was injected at 30 sites in the sub-epithelial bladder wall. Efficacy was assessed every month up to 12 months after injection, using a three-day frequency-volume chart (FVC) and postvoid residual urine (PVR), three questionnaires, and a simple score of Global Response Assessment (GRA). Failure was defined as when GRA was negative and additional treatment was administered.
Results: Nine men and eight women aged 67 ± 12 years were included. On FVC, frequencies of urgency, UUI and daytime urination significantly decreased up to the 11th month. PVR significantly increased at the first and second months but no patient required catheterization. The total scores of Overactive Bladder Symptom Score and International Consultation on Incontinence Questionnaire Short Form were significantly decreased for 10 and eight months, respectively. The score of GRA was significantly improved for eight months. The median time to failure was 11.0 months.
Conclusion: This study suggests that onabotulinumtoxinA submucosal injection is promising for refractory non-neurogenic OAB. It is anticipated that the treatment is effective for eight to nine months and approximately 40% of the patients do not require anticholinergics at the 12th month postoperatively.