Canadian guidelines for the evidence-based treatment of tic disorders: behavioural therapy, deep brain stimulation, and transcranial magnetic stimulation.

This clinical guideline provides recommendations for nonpharmacological treatments for tic disorders. We conducted a systematic literature search for clinical trials on the treatment of tics. One evidence-based review (including 30 studies) and 3 studies on behavioural interventions, 3 studies on deep brain stimulation (DBS), and 3 studies on transcranial magnetic stimulation (TMS) met our inclusion criteria. Based on this evidence, we have made strong recommendations for the use of habit reversal therapy and exposure and response prevention, preferably embedded within a supportive, psychoeducational program, and with the option to combine either of these approaches with pharmacotherapy. Although evidence exists for the efficacy of DBS, the quality of this evidence is poor and the risks and burdens of the procedure are finely balanced with the perceived benefits. Our recommendation is that this intervention continues to be considered an experimental treatment for severe, medically refractory tics that have imposed severe limitations on quality of life. We recommend that the procedure should only be performed within the context of research studies and by physicians expert in DBS programming and in the management of tics. There is no evidence to support the use of TMS in the treatment of tics. However, the procedure is associated with a low rate of known complications and could continue to be evaluated within research protocols. The recommendations we provide are based on current knowledge, and further studies may result in their revision in future.

A randomized, double-blind, placebo-controlled trial of metoclopramide for the treatment of Tourette's disorder.

OBJECTIVE: The pattern of dopamine antagonism by metoclopramide suggests benefits in the treatment of tic disorders. The purpose of this study was to examine the efficacy and safety of metoclopramide in the treatment of children and adolescents with tic disorders. METHOD: Twenty-seven medication-free patients (age 11.9 +/- 2.7 years) with Tourette's disorder or a chronic tic disorder participated in an 8-week double-blind, randomized, placebo-controlled trial of metoclopramide. Metoclopramide was started at 5 mg daily and titrated as needed to a maximum dose of 40 mg daily. Tics were rated every 2 weeks, and adverse effects, including weight, cardiac, and laboratory measures, were monitored. RESULTS: After 8 weeks of treatment, subjects receiving metoclopramide showed a 39% reduction in their total tic score on the Yale Global Tic Severity Scale, while subjects receiving placebo showed only a 13% reduction in tic severity (p = .001). Metoclopramide was well tolerated with no significant laboratory or cardiac changes noted other than an increase in serum prolactin. CONCLUSIONS: The results of this small controlled study suggest that metoclopramide is an effective and well-tolerated treatment for children and adolescents with tic disorders. Further trials are needed to confirm its efficacy and safety in pediatric patients and adults.

Brain magnetic resonance spectroscopy in Tourette's disorder.

OBJECTIVE: Although abnormalities of neural circuits involving the cortex, striatum, and thalamus are hypothesized to underlie Tourette's disorder, the neuronal abnormalities within components of these circuits are unknown. The purpose of this study was to examine the cellular neurochemistry within these circuits in Tourette's disorder using proton magnetic resonance spectroscopy, a method that has not previously been used in neurobiological investigations of the disorder. METHOD: Proton magnetic resonance spectroscopic imaging examinations were conducted in 25 males with Tourette's disorder (age 10.9 +/- 2.0 years) and 32 male comparison subjects (age 11.5 +/- 2.7 years). Spectra from frontal cortex, caudate nucleus, putamen, and thalamus were analyzed, and N-acetylaspartate, creatine, choline, myoinositol, and glutamate + glutamine were quantified and compared between the groups. RESULTS: Patients with Tourette's disorder demonstrated a reduction in N-acetylaspartate and choline in the left putamen, along with reduced levels of creatine bilaterally in the putamen. In the frontal cortex, patients had significantly lower concentrations of N-acetylaspartate bilaterally, lower levels of creatine on the right side, and reduced myoinositol on the left side. CONCLUSIONS: The results of this study suggest compromised neuronal integrity and deficits in density of neuronal and nonneuronal cells in components of the neural circuits implicated in Tourette's disorder.