To evaluate the efficacy of intravesical injection of botulinum toxin type A (BTX-A) for neurogenic detrusor 
overactivity (DO) in reducing the frequency and severity of autonomic dysreflexia (AD).

Design: A cross-sectional nonrandomized trial with before (baseline) and after (follow-up) assessments. Setting: A single spinal cord injury (SCI) rehabilitation center in China. Participants: Twenty-five patients with SCI at or above T6 and a history of AD who underwent urodynamic studies (UDS) before and 3 months after BTX-A injection. Interventions: Received bladder injection treatment wtih 200 U BTX-A. Outcome Measures: The maximum detrusor pressure(Pdetmax) and voume at first DO(VFIDC), baseline and overall maximum systolic blood pressure (SBP) during UDS, and scores of Incontinence Specific Quality of Life Instrument (IQoL) were recorded before and 3 months after the injection. The change in SBP (ΔSBP) from baseline to maximum SBP during UDS was calculated to assess the severity. The frequency of AD was recorded using ambulatory blood pressure monitoring during a 24 h period before and 3 months after the 
injection.

BTX-A injection decreased the Pdetmax and increased the VFIDC and mean urine volume per catheterization increased. The maximum SBP and the ΔSBP during UDS decreased significantly decreased after the injection (151.44 ± 13.92 vs 133.32 ± 9.20 mmHg and 49.44 ± 12.81 vs 33.08 ± 9.11 mmHg respectively, P < 0.05). The frequency of bladder-related ADs (i.e. performed a clean intermittent catheterization or leakage) during a 24-h period significantly decreased from 11.04 ± 1.81–7.88 ± 2.15 (P < 0.001).

Our study revealed that the severity and frequency of AD significantly decreased after BTX-A injection for NDO. This finding may prove to be a viable treatment strategy for the successful alleviation of AD episodes and amelioration of cardiovascular-related health risks associated with SCI. Reducing chronic cardiovascular and cerebrovascular complications of SCI would also dramatically improve the health and well-being of individuals with SCI and positively affect healthcare costs.

BTX-A decreases the severity of SBP increase and the number of AD episodes 3 months after intravesical injection.

Lockwood G, Durkee C, Groth T. Intravesical botulinum toxin for persistent autonomic dysreflexia in a pediatric patient. Case Rep Urol 2016;2016:4569684.
Jung IY, Mo KI, Leigh JH. Effect of intravesical botulinum toxin injection on symptoms of autonomic dysreflexia in a patient with chronic spinal cord injury: a case report. J Spinal Cord Med 2017; 42(6):806–809.
Vaidyanathan S, Soni BM, Hughes PL, Oo T. Fatal cerebral hemorrhage in a tetraplegic patient due to autonomic dysreflexia triggered by delay in emptying urinary bladder after unsuccessful intermittent catheterization by carer: lessons learned.Int Med Case Rep J. 2018-03-07;11:53-58.