Evidence-based systematic review on the efficacy and safety of botulinum toxin-A therapy in post-stroke spasticity

Botulinum toxin type A (BoNTA) has been suggested as an effective anti-spastic drug. In this article, we summarized the data of randomized, placebo-controlled, double- blind trials and conducted a meta-analysis to assess if BoNTA is an adequate treatment for spasticity following stroke.

To evaluate the relevant literature and assess the effectiveness and safety of BoNTA in (1) reducing spasticity based on mean change in the Modified Ashworth Scale (MAS) for upper and lower limb spasticity from baseline; (2) reducing spasticity based on the percent of patients having > or = 1point(s) change in the MAS; (3) improving the patient's or caregivers' Global Assessment Scale (GAS); and (4) total adverse events.

We selected all randomized, placebo controlled, double-blind clinical trials or previous meta-analyses evaluating the efficacy and safety of BoNTA (Botox or Dysport) for the treatment of spasticity in both upper and lower limbs after stroke. Validity assessment of studies was performed, and Revman 4.2.7 from Cochrane Collaboration and SPSS (statistical package for the social sciences), v 9.0, were applied for analysis.

Overall analysis showed clinical improvement between baseline and 4-6 weeks after application of BoNTA of the patient's spasticity score using the MAS (weighted mean difference [WMD] = 0.87, 95% CI = 0.52-1.22). The odds ratio of the MAS spasticity score showing one or more points improvement at 4-6 weeks after giving BoNTA showed clinically significant improvement (OR = 4.5, 95% CI = 2.79-7.25). The odds ratio of having an improved GAS at 4-6 weeks after injecting BoNTA showed clinically significant improvement (Odds ratio = 5.85, 95% CI = 3.12-10.95). The odds ratio of having an adverse event during the entire study did not show any significant difference between placebo and BoNTA (odds ratio = 0.84, 95% CI = 0.55-1.28).

BoNTA improves muscle tone in upper and lower limb spasticity following stroke. A global assessment of improvement was noted by the patients or the caregivers following BoNTA injection. BoNTA is considered a safe therapeutic agent.