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Tic disorders affect 4-18% of children at point in time. This ranges from a single tic for a short period of time to multiple chronic motor and vocal tics lasting more than one year, i.e., Tourette's syndrome. Tics are abrupt and recurrent motor or vocal actions. Although involuntary, they may be preceded by a sensory urge, are sometimes suppressed for prolonged periods, and can be triggered by external perceptions. They are sudden and purposeless. They can be divided into simple tics such as blinking, shrugging of the shoulders, grunting, and clearing one's throat, and complex tics such as licking, jumping, or touching objects. The best known symptom of Tourette's syndrome, coprolalia (a complex vocal tic with involuntary swearing), occurs in less than 15%. Most tic disorders including Tourette's need little medical attention other than help with diagnosis and information, but an unusual or severe movement disorder requires treatment. The onset of Tourette's syndrome occurs around the age of 6-7 years, and, as with other neurodevelopmental disorders, it occurs more commonly in boys. Parents and children need to understand that, although all these symptoms relate to the underlying brain disorder, interventions may be extremely simple—for example, allowing the child to have a short "tic break" in a long school lesson. The neurochemistry, neuroanatomy, and genetics of Tourette's syndrome have been the subject of speculation and research; dopaminergic pathways in the frontal and subcortical regions of the brain are involved, and a strong genetic basis exists. Recent studies have identified a group of children who suddenly develop tics and obsessive compulsive disorder associated with B-haemolytic streptococcal sore throat infection. However, there is no evidence currently that these children should be investigated or treated differently from other children with Tourette's syndrome, other than by looking for and treating active streptococcal infection. No drug has predictable and potent efficacy in all children with tics—most studies show a reduction of only about 30% in the severity of tics. Few good quality, randomized controlled trials are available. Double blind trials have shown tic severity and frequency are reduced using dopamine antagonists, such as haloperidol, pimozide, sulpiride, risperidone, and the The other medications all have some risk of long-term side-effects. Haloperidol is the most popular, but may be replaced by the more expensive atypical anti-psychotics, e.g. sulpiride and risperidone (Risperdal), because of concerns over tardive dyskinesia side-effects. My favorite atypical is ziprasidone (Geodon) because of its better side-effect profile and lower cost ($140/month), especially when using once a day dosing. It hasn't been researched with Tourette's, but looking at the research, it is very likely that it would be just as good as Haldol, risperidone, or sulpiride since it works in very similar ways. Baclofen Helped Some in DB: A very small DB PC 4-week crossover study with a two week washout with 10 children with Tourette's Syndrome completed by Johns Hopkins comparing baclofen 20 mg t.i.d. found significant decreases in symptoms but not primarily in tics. Baclofen treatment in Tourette syndrome: a double-blind, placebo-controlled, crossover trial. Singer HS, Wendlandt J, Krieger M, Giuliano J. Neurology. 2001 Mar 13;56(5):599-604 Clonidine as Good as Risperidone for Tourette’s: In a DB PC study of 21 children and teens with Tourette's syndrome. risperidone and clonidine appeared equally effective. Risperidone produced a mean reduction in the YGTSS of 21%; clonidine produced a 26% reduction. Among subjects with comorbid obsessive-compulsive symptoms, 63% of the risperidone group and 33% of the clonidine group responded to treatment (not significant). Sedation, the most common side-effect, resolved with continued administration of the medication or with a dose reduction. Risperidone versus clonidine in the treatment of children and adolescents with Tourette's syndrome. Gaffney GR, Perry PJ, et al. University of Iowa. J Am Acad Child Adolesc Psychiatry. 2002 Mar;41(3):330-6. Genetic Abnormal SLITRK1 Accounted for 3% of TS in Study: In a study of 174 unrelated children with TS, three had abnormal Slit and Trk-like 1 (SLITRK1) genes on chromosome 13q31.1: one a frameshift mutation and two independent occurrences of the identical variant in the binding site for microRNA hsa-miR-189. These variants were absent from 3600 control chromosomes. SLITRK1 mRNA and hsa-miR-189 showed an overlapping expression pattern in brain regions previously implicated in TS. Wild-type SLITRK1, but not the frameshift mutant, enhanced dendritic growth in primary neuronal cultures. Sequence variants in SLITRK1 are associated with Tourette's syndrome. Abelson JF, et al. Yale University. Science 2005 Oct 14;310(5746):317-20. Risperidone Did Better Than Pimozide in Small DB: In a random assigned DB 4 week study of 19 children with Tourette's, using the Yale Global Tic Severity Scale (YGTSS), risperidone treatment was associated with significantly lower tic severity scores (YGTSS: baseline 43, pimozide 34.2, risperidone 25.2; p =.05). Weight gain during the 4-week treatment periods was greater for risperidone (mean 1.9 kg) than pimozide (1.0 kg). Tic Reduction With Risperidone Versus Pimozide in a Randomized, Double-Blind, Crossover Trial. Gilbert DL, Batterson JR, Sethuraman G, Sallee FR. J Am Acad Child Adolesc Psychiatry. 2004 Feb; 43(2): 206-214
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2 adrenergic receptor agonist, clonidine. A couple more recent studies are mentioned below. Clonidine is the most mild and inexpensive intervention, but uncomfortable side-effects, such as dry mouth, dizziness, and constipation, may cause some patients to stop using it. Clonidine is also a useful medication for high blood pressure.