Objectives: Detrusor injections with botulinum toxin type A are an effective treatment for neurogenic detrusor overactivity, lasting for 9-12 months. When the patients develop botulinum resistance, subsequent injections might be less effective. Repeat injections in patients with severe neurogenic detrusor overactivity and incontinence were studied.
Methods: Patients received Botox (300 UI) or Dysport (750 UI) injections. Clinical variables: satisfaction, anticholinergics use, mean and maximum bladder capacity, continence volume. Cystometric parameters: compliance, cystometric capacity, reflex volume.
Statistics: Anova, chi2-tests; t-tests and paired t-tests (p=0.05).
Results: Forty-three men and 23 women (mean age 38.3 years; mean duration of lesion 9.2 years) were included. The interval between subsequent injections (on average 9-11 months) did not change significantly (p=0.5594). The satisfaction was high and anticholinergics use decreased substantially (p=0.0000). Significant improvements were found in clinical parameters and in cystometric capacity, for compliance only at the second treatment. The incidence of reflex contractions was significantly reduced. Four patients had transient adverse events after Dysport.
Conclusions: Repeat injections with botulinum toxin type A are as effective as the first one. The cause for repeat treatment is relapse of overactive bladder symptoms.