Safety and Efficacy of Botulinum Toxin A for Treatment of Overactive Bladder in Parkinson's Disease

Overactive bladder is defined by the International Continence Society as a syndrome characterized by symptoms of urinary urgency, often accompanied by frequency and nocturia, with or without urge incontinence, but without urinary tract infection or other definite symptoms pathological changes. Bladder dysfunction is one of the most common autonomic nervous disorders in Parkinson's disease (PD). Up to 70% of PD patients have bladder hyperactivity. Nocturia is the most commonly reported symptom , followed by urinary frequency, urinary urgency and urge incontinence, affecting patients' quality of life and social life. At present, intramuscular injection of 100U botulinum toxin (BoNT-A) is a reasonable choice for the treatment of bladder overactivity in PD, and it has been proved to be a safe and effective method for the treatment of neurogenic detrusor overactivity, especially for patients with insufficient response to anticholinergic drugs,which is a Grade Ia recommendation in the EAU guidelines. There are some problems in the current research as follows: 1. Single-arm study, non-randomized control, and small sample size; 2. Only patients with urinary incontinence but not patients with dry bladder overactivity were included; 3. Patients with urinary retention are not excluded, resulting in urinary retention after injection of botulinum toxin, affecting the experience of patients; 4. Botulinum toxin dose injection varies, there is still a lack of large-scale prospective clinical studies to reflect the relationship between botulinum toxin dose and residual urine volume; 5. The urodynamic index was used in the outcome index, which could not reflect the improvement of symptoms sensitively and objectively. In order to make up for the shortcomings of previous studies, a randomized controlled trial is planned to confirm the efficacy and safety of intramuscular injection of low dose botulinum toxin in the treatment of PD bladder overactivity