Gilles de la Tourette syndrome, also called simply Tourette syndrome, is a disorder characterized by multiple motor and vocal tics that begins before age 18.
Causes, incidence, and risk factors
Tourette syndrome, first described by Georges Gilles de la Tourette in 1885, is a complex condition that arises during childhood or adolescence. It is characterized by repeated and involuntary body movements (tics). A tic is a sudden, rapid, repetitive motor movement or vocalization. Tics can include eye blinking, repeated throat clearing or sniffing, arm thrusting, kicking movements, shoulder shrugging or jumping.
The prevalence of Tourette syndrome is estimated at 2% of the general population. This may be a conservative estimate, since many people with very mild tics may be unaware of them and never seek medical attention. Tourette syndrome is four times as likely to occur in boys as in girls.
Though a gene for Tourette syndrome has not yet been identified, there is strong evidence that it is an inherited disorder transmitted through one or more genes. It is an autosomal dominant trait.
Famous people with Tourette syndrome include Mahmoud Abdul-Rauf (formerly Chris Jackson), Jim Eisenreich, and Mozart.
The most common initial symptom is a facial tic — other tics may follow. Contrary to popular belief, use of socially inappropriate words or phrases (coprolalia) occurs in only a minority of patients. Tics may occur many times a day, but they tend to improve or worsen at different times. The nature of the tics may vary and change with time.
Many patients explain that the tics are not totally involuntary, but that “things just would not feel right” if they did not do them. In this respect Tourette syndrome differs from obsessive-compulsive disorder, in which patients are compelled to do the behaviors out of fear of impending doom.
Signs and tests
There are no specific lab tests to confirm a diagnosis of Tourette syndrome. However, a thorough examination by a qualified physician should be performed to rule out other causes of these symptoms.
- Both multiple motor and one or more vocal tics have been present at some time during the illness, although not necessarily at the same time.
- Tics occur many times a day, nearly every day or intermittently, throughout a period of more than 1 year. During this period there must not be a tic-free period of more than 3 consecutive months.
- Onset is before 18 years of age.
Many patients with Tourette syndrome have very minor symptoms. In this case, they are not treated, since the medications have side effects that would be worse than the symptoms. Antipsychotic medications such as haloperidol (Haldol) and pimozide have historically been used to treat Tourette syndrome.
Although these medications may be effective in diminishing or eliminating tics, their use is restricted by significant side effects. These include movement disorders and cognitive effects. Risperidone is another antipsychotic drug that may be used for this disorder.
Clonidine has had beneficial effects on suppression of tics. Another drug commonly used is tetrabenazine, but this too has the risk of causing depression or a movement disorder. Many other treatments have been tried with little or no improvement.