Poster 195: The Effect of Repeated Treatment of Botulinum Toxin Type A on Poststroke, Spasticity-Related Pain: A Subgroup Analysis of Patients in a 12-Month Trial

Abstract

Objective: To evaluate the efficacy and safety of repeated botulinum toxin type A (BTX-A) (Botox) treatment of focal upper-limb poststroke spasticity in reducing pain frequency and intensity. Design: Multicenter, open-label, repeated dose study. Setting: 35 clinical sites in North America. Participants: Patients with upper-limb poststroke spasticity were enrolled in a 12-month study of BTX-A (N=279). A post hoc subgroup analysis of 73 patients (mean age, 56.8y; 56.2% women) who scored ≥2 on the pain component of the 4-point Disability Assessment Scale (DAS; 0 [no pain] to 3 [severe pain]) at baseline was performed. Interventions: Patients received up to 5 treatments of 200 to 400U of BTX-A in the elbow, wrist, finger, and/or thumb flexors of the affected limb. Successive treatments were administered at least 12 weeks after the previous injection. Patients were assessed every 6 weeks for 12 months. Main Outcome Measures: Change from baseline in pain frequency (0 [none of the time] to 4 [all of the time]), pain intensity (0 [no pain] to 10 [pain as bad as it can be]), DAS (pain domain), and muscle tone (Ashworth Scale) following BTX-A treatment. Adverse events (AEs) were documented. Results: Pain frequency, DAS (pain domain), and muscle tone were significantly reduced from baseline at all time points (P≤.05) after BTX-A treatment. Mean DAS pain reductions ranged from 0.9 to 1.1. Average pain intensity was significantly reduced from baseline at all time points (P≤.05), except week 54. Mild-to-moderate treatment-related AEs were reported in 6.8% (5/73) of patients. Conclusions: Repeated BTX-A treatment was well tolerated and resulted in a significant decrease in pain frequency and intensity in spastic upper limbs.