Reduction in Bladder-Related Autonomic Dysreflexia after OnabotulinumtoxinA Treatment in Spinal Cord Injury

Bladder-related events, including neurogenic detrusor overactivity, are the leading cause of autonomic dysreflexia in spinal cord injured individuals. Self-reported autonomic dysreflexia is reduced following onabotulinumtoxinA treatment for neurogenic detrusor overactivity; however, none of these trials have assessed autonomic dysreflexia events using the clinical cutoff of an increase in systolic blood pressure ≥20 mm Hg. This study used a prospective, open-labelled design from 2013 to 2014 to quantitatively assess the efficacy of one cycle 200 U intradetrusor-injected onabotulinumtoxinA (20 sites) on reducing the severity and frequency of bladder-related autonomic dysreflexia events and improving quality of life. Twelve men and five women with chronic, traumatic spinal cord injuries at or above the sixth thoracic level, and concomitant autonomic dysreflexia and neurogenic detrusor overactivity, underwent blood pressure monitoring during urodynamics and over a 24 h period using ambulatory blood pressure monitoring pre- and 1 month post-treatment. Post-onabotulinumtoxinA, autonomic dysreflexia severity was reduced during urodynamics (systolic blood pressure increase: 42 ± 23 mm Hg vs. 20 ± 10 mm Hg, p < 0.001) and during bladder-related events across the 24 h period (systolic blood pressure increase: 49 ± 2 mm Hg vs. 26 ± 22 mm Hg, p = 0.004). Frequency of 24 h bladder-related autonomic dysreflexia events was also decreased post-onabotulinumtoxinA (4 ± 2 events vs. 1 ± 1 events, p < 0.001). Autonomic dysreflexia and incontinence quality of life indices were also improved post-onabotulinumtoxinA (p < 0.05). Intradetrusor injections of onabotulinumtoxinA for the management of neurogenic detrusor overactivity in individuals with high level spinal cord injuries decreased the severity and frequency of bladder-related episodes of autonomic dysreflexia, and improved bladder function and quality of life.