What is Tourette syndrome?
Tourette syndrome (TS) is an inherited, neurological disorder characterized by repeated involuntary movements and uncontrollable vocal (phonic) sounds called tics. In a few cases, such tics can include inappropriate words and phrases.
The disorder is named for Dr. Georges Gilles de la Tourette, the pioneering French neurologist who first described an 86-year-old French noblewoman with the condition in 1885.
The symptoms of TS generally appear before the individual is 18 years old. TS can affect people of all ethnic groups; males are affected 3 to 4 times more often than females. It is estimated that 100,000 Americans have full-blown TS, and that perhaps as many as 1 in 200 show a partial expression of the disorder, such as chronic multiple tics or transient childhood tics.
The natural course of TS varies from patient to patient. Although TS symptoms range from very mild to quite severe, the majority of cases fall in the mild category.
What are the symptoms?
The first symptoms of TS are usually facial tics–commonly eye blinking. However, facial tics can also include nose twitching or grimaces. With time, other motor tics may appear such as head jerking, neck stretching, foot stamping, or body twisting and bending.
TS patients may utter strange and unacceptable sounds, words, or phrases. It is not uncommon for a person with TS to continuously clear his or her throat, cough, sniff, grunt, yelp, bark, or shout.
People with TS may involuntarily shout obscenities (coprolalia) or constantly repeat the words of other people (echolalia). They may touch other people excessively or repeat actions obsessively and unnecessarily. A few patients with severe TS demonstrate self-harming behaviors such as lip and cheek biting and head banging against hard objects. However, these behaviors are extremely rare.
Tics alternately increase and decrease in severity, and periodically change in number, frequency, type, and location. Symptoms may subside for weeks or months at a time and later recur.
How are tics classified?
There are two categories of tics: simple and complex. Simple tics are sudden, brief movements that involve a limited number of muscle groups. They occur in a single or isolated fashion and are often repetitive. Some of the more common examples of simple tics include eye blinking, shoulder shrugging, facial grimacing, head jerking, yelping, and sniffing. Complex tics are distinct, coordinated patterns of successive movements involving several muscle groups. Complex tics might include jumping, smelling objects, touching the nose, touching other people, coprolalia, echolalia, or self-harming behaviors.
Can people with TS control their tics?
People with TS can sometimes suppress their tics for a short time, but the effort is similar to that of holding back a sneeze. Eventually tension mounts to the point where the tic escapes. Tics worsen in stressful situations; however they improve when the person is relaxed or absorbed in an activity. In most cases tics decrease markedly during sleep.
What causes TS?
Although the basic cause of TS is unknown, current research suggests that there is an abnormality in the gene(s) affecting the brain’s metabolism of neurotransmitters such as dopamine, serotonin, and norepinephrine. Neurotransmitters are chemicals in the brain that carry signals from one nerve cell to another.
What disorders are associated with TS?
Not all people with TS have disorders other than tics. However, many people experience additional problems such as obsessive compulsive behavior, where the person feels that something must be done repeatedly, such as hand washing or checking that a door is locked; attention deficit disorder, where the person has difficulty concentrating and is easily distracted; learning disabilities, which include reading, writing, arithmetic, and perceptual difficulties; problems with impulse control, which can result in overly aggressive behaviors or socially inappropriate acts; or sleep disorders, which include frequent awakenings or talking in one’s sleep.
The wide range of behavioral symptoms that can accompany tics may, in fact, be more disabling than the tics themselves. Patients, families, and physicians need to determine which set of symptoms is most disabling so that appropriate medications and therapies can be selected.
How is TS diagnosed?
Generally, TS is diagnosed by observing the symptoms and evaluating family history. For a diagnosis of TS to be made, both motor and phonic tics must be present for at least 1 year. Neuroimaging studies, such as magnetic resonance imaging (MRI), computerized tomography (CT), and electroencephalogram (EEG) scans, or certain blood tests may be used to rule out other conditions that might be confused with TS. However, TS is a clinical diagnosis. There are no blood tests or other laboratory tests that definitively diagnose the disorder.
Studies show that correct diagnosis of TS is frequently delayed after the start of symptoms because many physicians may not be familiar with the disorder. The behavioral symptoms and tics are easily misinterpreted, often causing children with TS to be misunderstood at school, at home, and even in the doctor’s office. Parents, relatives, and peers who are unfamiliar with the disorder may incorrectly attribute the tics and other symptoms to psychological problems, thereby increasing the social isolation of those with the disorder. And because tics can wax and wane in severity and can also be suppressed, they are often absent during doctor visits, which further complicates making a diagnosis.
In many cases, parents, relatives, friends, or even the patients themselves become aware of the disorder based on information they have heard or read in the popular media.
How is TS treated?
Because symptoms do not impair most patients and development usually proceeds normally, the majority of people with TS require no medication. However, medications are available to help when symptoms interfere with functioning. Unfortunately, there is no one medication that is helpful to all persons with TS, nor does any medication completely eliminate symptoms; in addition, all medications have side effects. Instead, the available TS medications are only able to help reduce specific symptoms.
Some patients who require medication to reduce the frequency and intensity of the tic symptoms may be treated with neuroleptic drugs such as haloperidol and pimozide. These medications are usually given in very small doses that are increased slowly until the best possible balance between symptoms and side effects is achieved.
Recently scientists have discovered that long-term use of neuroleptic drugs may cause an involuntary movement disorder called tardive dyskinesia. However, this condition usually disappears when medication is discontinued. Short-term side effects of haloperidol and pimozide include muscular rigidity, drooling, tremor, lack of facial expression, slow movement, and restlessness. These side effects can be reduced by drugs commonly used to treat Parkinson’s disease. Other side effects such as fatigue, depression, anxiety, weight gain, and difficulties in thinking clearly may be more troublesome.
Clonidine, an antihypertensive drug, is also used in the treatment of tics. Studies show that it is more effective in reducing motor tics than reducing vocal tics. Fatigue, dry mouth, irritability, dizziness, headache, and insomnia are common side effects associated with clonidine use. Fluphenazine and clonazepam may also be prescribed to help control tic symptoms.
Medications are also available to treat some of the associated behavioral disorders. Stimulants such as methyphenidate, pemoline, and dextroamphetamine, usually prescribed for attention deficit disorders, although somewhat effective, have also been reported to increase tics; therefore their use is controversial. For obsessive compulsive behaviors that significantly disrupt daily functioning, fluoxetine, clomipramine, sertraline, and paroxetine may be prescribed.
Other types of therapy may also be helpful. Although psychological problems do not cause TS, psychotherapy may help the person better cope with the disorder and deal with the secondary social and emotional problems that sometimes occur. Psychotherapy does not help suppress the patient’s tics.
Relaxation techniques and biofeedback may be useful in alleviating stress which can lead to an increase in tic symptoms.
Is TS inherited?
Evidence from genetic studies suggests that TS is inherited in a dominant mode and the gene(s) involved can cause a variable range of symptoms in different family members. A person with TS has about a 50-50 chance of passing on the gene(s) to one of his or her offspring. However, that genetic predisposition may not necessarily result in full-blown TS; instead, it may express itself as a milder tic disorder or as obsessive compulsive behaviors or possibly attention deficit disorder with few or no tics at all. It is also possible that the gene-carrying offspring will not develop any TS symptoms. A higher than normal incidence of milder tic disorders and obsessive compulsive behaviors has been found in families of individuals with TS.
Gender also plays an important role in TS gene expression. If the gene-carrying offspring of a TS patient is male, then the risk of developing symptoms is 3 to 4 times higher. However, most people who inherit the gene(s) will not develop symptoms severe enough to warrant medical attention. In some cases of TS, inheritance cannot be determined. These cases are called sporadic and their cause is unknown.
What is the prognosis?
There is no cure for TS; however, the condition in many individuals improves as they mature. Individuals with TS can expect to live a normal life span. Although the disorder is generally lifelong and chronic, it is not a degenerative condition. TS does not impair intelligence. Tics tend to decrease with age, enabling some patients to discontinue using medication. In a few cases, complete remission occurs after adolescence. Although tic symptoms tend to decrease with age, it is possible that neuropsychiatric disorders such as depression, panic attacks, mood swings, and antisocial behaviors may increase.
What is the best educational setting for children with TS?
Although students with TS often function well in the regular classroom, it is estimated that many may have some kind of learning disability. When attention deficit disorder, obsessive compulsive disorder, and frequent tics greatly interfere with academic performance or social adjustment, students should be placed in an educational setting that meets their individual needs. These students may require tutoring, smaller or special classes, and in some cases special schools.
All students with TS need a tolerant and compassionate setting that both encourages them to work to their full potential and is flexible enough to accommodate their special needs. This setting may include a private study area, exams outside the regular classroom, or even oral exams when the child’s symptoms interfere with his or her ability to write. Untimed testing reduces stress for students with TS.
What research is being done?
Within the Federal Government, the leading supporter of research on TS and other neurological disorders is the National Institute of Neurological Disorders and Stroke (NINDS). The NINDS, a part of the National Institutes of Health (NIH), is responsible for supporting and conducting research on the brain and central nervous system.
NINDS sponsors research on TS both in its laboratories at the NIH and through grants to major medical institutions across the country. The National Institute of Mental Health, the National Center for Research Resources, the National Institute of Child Health and Human Development, the National Institute on Drug Abuse, and the National Institute on Deafness and Other Communication Disorders also support research of relevance to TS.
Recent research has led to several notable advances in the understanding of TS. Already scientists have learned that TS is inherited from a dominant gene(s) that causes different symptoms from patient to patient, and that the disorder is more common than was previously thought.
Genetic studies. Currently, investigators are conducting genetic linkage studies in large multigenerational families affected with TS in an effort to find the chromosomal location of the TS gene(s). Finding a genetic marker (a biochemical abnormality that all TS patients might share) for TS would be a major step toward understanding the genetic risk factors for TS. Once the marker is found, research efforts would then focus on locating the TS gene(s).
Understanding the genetics of TS will directly benefit patients who are concerned about recurrence in their families and will ultimately help to clarify the development of the disorder. Localization of the TS gene will strengthen clinical diagnosis, improve genetic counseling, lead to the clarification of pathophysiology, and provide clues for more effective therapies.
Neurotransmitter studies. Investigators continue to study certain neurotransmitters to increase our understanding of the syndrome, explore the role they play in the disease process, and provide more effective therapies.
Environmental studies. Other research projects currently under way include analyzing young unaffected children at high risk for TS in order to identify environmental factors such as life stresses or exposure to certain medications that may influence the expression of the disorder.
Scientists are also conducting neuropsychological tests and neuroimaging studies of brain activity and structure to determine the extent to which specific environmental exposures may affect the emergence of tics and/or obsessive compulsive symptoms.
Tourette’s, Other Tic Disorders Far More Common Than Once Thought One out of four students in special-education classes has a tic-related disorder like Tourette syndrome, and the rate of Tourette’s among students in the general population is 50 to 75 times higher than has been traditionally thought by doctors, according to a study published in the Oct. 23 issue of the journal Neurology.
Office of Scientific and Health Reports
National Institute of Neurological Disorders and Stroke
National Institutes of Health
Bethesda, MD 20892
NIH Publication No. 95-2163
Original Publication Date: February 1995