Botulinum toxin for simple motor tics - A randomized, double-blind, controlled clinical trial

Objective: To determine the effect of injections of botulinum toxin on simp le motor ties. Background: Case series with unblinded assessments have repo rted improvement in tic frequency and associated urge with botulinum toxin. Methods: Patients with suitable simple motor ties were randomized to recei ve botulinum toxin and placebo in a double blind, crossover design. All out comes compared week 2 to baseline measurements. The primary outcome measure was the number of treated ties per minute on a videotape segment. Secondar y outcome measures were number of untreated ties per minute, the Shapiro To urette Syndrome Severity Scale score, a numerical assessment of the urge to perform the treated tic (0 to 4), the premonitory sensation associated wit h the treated tic (0 to 4), and the patient's global impression of change. Results: Eighteen patients completed the study. The median relative change in treated ties per minute with botulinum toxin was -0.39 (or a 39% reducti on) versus 0.058 (or a 5.8% increase) with placebo (net effect -0.37, p = 0 .0007). The average change in urge scores (score range 0 to 4) was -0.46 in the treatment phase and +0.49 in the placebo phase (net effect 0.94, p = 0 .02). Other secondary outcome measures were not significantly different bet ween the two groups. Conclusion: Botulinum toxin reduced treated tic freque ncy and the urge associated with the treated tie. Despite these changes, pa tients did not report an overall benefit from the treatment. Careful consid eration of the contribution of the target tic to the patient's disability i s needed before making treatment decisions.