Long-Term Discontinuation of Botulinum Toxin A Intradetrusor Injections for Neurogenic Detrusor Overactivity: A Multicenter Study.

[PURPOSE] Data are lacking on long-term outcomes of intradetrusor injections of botulinum toxin A for neurogenic detrusor overactivity. The aim of this study was to assess the outcomes of intradetrusor injections of botulinum toxin A for neurogenic detrusor overactivity after more than 10 years of followup.

[MATERIALS AND METHODS] We retrospectively reviewed the charts of all consecutive neurological patients who had received onabotulinumtoxin A or abobotulinumtoxin A intradetrusor injections for neurogenic detrusor overactivity between January 2002 and November 2007 at a total of 3 academic centers. The primary outcome measure was the 10-year discontinuation rate. Other outcomes of interest were failure, reasons for discontinuation and subsequent treatments of neurogenic detrusor overactivity. Discontinuation-free and failure-free survival was estimated by Kaplan-Meier analyses.

[RESULTS] A total of 140 patients were included in study. The 10-year discontinuation-free and failure-free survival rates were 49.1% and 73%, respectively. The most common reason for discontinuation was failure in 43.7% of cases, which was primary and secondary in 17.2% and 26.5%, respectively. Secondary failure occurred after a median of 8 injections and a median of 80.1 months from the first injection. Other reasons for discontinuation were patient decision in 28.1% of patients, nonbotulinum toxin A related improvement of urinary incontinence in 14.1%, neurological condition progression in 12.5% and an adverse event in 1.6%. Discontinuation-free survival was significantly poorer in patients with spina bifida than in patients with multiple sclerosis or spinal cord injury (p = 0.02).

[CONCLUSIONS] More than half of the patients with neurogenic detrusor overactivity discontinued intradetrusor botulinum toxin A within the first 10 years after the initial injection. Patients with spina bifida are at high risk for discontinuation.