[Seven years of botulinum toxin type A in the treatment of neurogenic detrusor hyperactivity]

A decompensated storage function with high pressures is the greatest risk factor regarding life expectancy and quality of life in patients with neurogenic detrusor hyperactivity. Previously, this problem could only be managed with administration of anticholinergic medications or--if this approach was either not effective enough or the patients exhibited drug intolerance--by invasive surgical interventions. The use of botulinum toxin type A to treat these patients rapidly proved to be a beneficial alternative to those two therapeutic options ever since its introduction in Germany in 1998 as a minimally invasive procedure and has become established worldwide.

The medical records of first-time users at the clinic were retrospectively analyzed for a 7-year period. The total of 492 injections in 277 patients--of which 365 injections in 216 patients were performed following a standardized protocol--represents the largest number of cases worldwide. The treatment was indicated in patients experiencing insufficient efficacy of anticholinergic agents or drug intolerance who were capable of self-catheterization.

The standard injection contained either 300 MU Botox or 750 MU Dysport. Urodynamic parameters before and up to 8 months post-intervention showed significantly lowered detrusor pressure and improved cystometric capacity. This corresponded to the clinical assessment and subjective impression of the patients that detrusor activity had been reduced to a large extent with improved continence. Evacuation was carried out in all cases without any difficulty by aseptic intermittent catheterization. The average duration of the effect was subjectively determined to be 8.7 months. In the vast majority of cases, anticholinergic medications could be discontinued or considerably reduced. Side effects not requiring treatment developed in only four instances. Antibody formation no longer occurred with those products available on the market since 2001. Even after repeated injections (up to ten times) there was no evidence for decreased efficacy.

Due to its reliable effect and low rate of side effects, botulinum toxin type A quickly became accepted worldwide for the treatment of neurogenic detrusor hyperactivity and has contributed to a substantial enrichment of the more conservative therapy options. Prospective studies focusing especially on injection site and optimizing the duration of efficacy are desirable.