Login to Access Video or Poster Abstract: MP85-16
Sources of Funding: None

Introduction

Following spinal cord injury (SCI), disruption to neuronal pathways of the bladder can lead to neurogenic detrusor over-activity (NDO) causing reduced capacity, high pressure and incontinence. Intra-detrusor injections of botulinum toxin A (BTX-A) are commonly used to manage these complications. Between 2013-2014 our department changed from using abobotulinum toxin (aboBTX) (750-1000 u) to onabotulinum toxin (onaBTX) (200 u). We have analysed the urodynamic outcomes and patient satisfaction to determine the relative efficacy of the two drugs on NDO following SCI.

Methods

The medical notes of 171 patients receiving consecutive doses of aboBTX and onaBTX during 2013-2014 were reviewed. 36 SCI patients with NDO and urodynamics within 6 months of injection of both aboBTX and onaBTX were included. The maximum cystometric capacity (MCC) and maximum detrusor pressure (MDP) were recorded. Paired t-tests were performed to test difference in bladder function between the two BTX-A drugs.

Results

The post-injection mean (± SD) MCC for aboBTX was 375 ± 178 ml and for onaBTX was 378 ± 212 ml. The post injection mean (± SD) MDP for aboBTX was 25 ± 21 cmH₂O and for onaBTX was 27 ± 18 cmH₂O. There was no significant difference between MCC (p=0.5) and MDP (p=0.86) for each drug. The scatter graphs demonstrate the relationship between the preparations with respect to MCC and MDP. The solid line represents the linear regression and the dashed line represents a 1:1 relationship. The linear regression for MCC had a slope of 1 demonstrating a clear correlation between the bladder capacity after aboBTX and onaBTX. There was not such a clear correlation between the MDP data. 12 out of 36 patients reported worse satisfaction with onaBTX than aboBTX, though interestingly this did not correlate with worse urodynamic outcomes.

Conclusions

There was no statistically significant difference in objectively measured urodynamic parameters of bladder function between aboBTX and onaBTX in patients with NDO following SCI. However 1/3 of patients reported worse satisfaction with onaBTX. The data will be further analysed to compare the efficacy of repeated injections and the effect of prior exposure to each agent.

Funding

None