Tourette syndrome (TS) is a neurological disorder characterized by repetitive, stereotyped, involuntary movements and vocalizations called tics. The disorder is named for Dr. Georges Gilles de la Tourette, the pioneering French neurologist who in 1885 first described the condition in an 86-year-old French noblewoman.
The early symptoms of Tourette syndrome are almost always noticed first in childhood, with the average onset between the ages of 7 and 10 years.
Tourette syndrome occurs in people from all ethnic groups; males are affected about three to four times more often than females. It is estimated that 200,000 Americans have the most severe form of Tourette syndrome, and as many as one in 100 exhibit milder and less complex symptoms such as chronic motor or vocal tics or transient tics of childhood.
Although Tourette syndrome can be a chronic condition with symptoms lasting a lifetime, most people with the condition experience their worst symptoms in their early teens, with improvement occurring in the late teens and continuing into adulthood.
Tourette's syndrome is a complex neuropsychiatric condition characterized by the presence of tics, which are usually associated with other disorders such as:
This tic disorder was first described by Georges Gilles de la Tourette in 1885.
The first signs and symptoms are seen most often around the ages of 6 to 8; however, in some cases the first signs are seen at an earlier age, and in other cases they start in adolescence.
Tourette's syndrome occurs in about 0.5% of school age children, but when chronic tic disorders are included, the prevalence increases to 2% of the general population.
The leading sign of Tourette's syndrome, and the most common reason for referral for consultation, is the presence of tics. However, it is worthwhile to mention that even though tics might be disabling, they are not necessarily, as will be discussed later on, the most disabling problem in persons with Tourette's syndrome.
Tics are repetitive, involuntary or semi-voluntary, short lasting, stereotyped movements (motor tics) or vocalizations (phonic tics), of sudden presentation, usually in clusters. There are many clinical varieties of tics that can affect any part of the body, but they are more common in the face, trunk, and shoulders.
Traditionally, tics have been divided in two main groups:
- motor tics;
- vocal tics.
The motor tics are described as simple motor tics when they involve a single muscle, orcomplex motor tics when they consists of a more coordinated movement resembling a normal function.
Similarly, the vocal tics can be simple vocal tics when they consist of simple sounds or complex when the they consist in the production of words or sentences (complex phonic tics).
The following are examples of tics commonly seen in persons with Tourette's:
Simple motor tics include:
- eye blinking,
- shoulder rotation or elevation,
- head jerking,
- lip contractions,
- closing of the eyes,
- eyes rolling in the orbits,
- torticollis (turning the neck to one side),
- opening and closing of the mouth,
- abdominal contractions,
- stretching of arms and legs.
Complex motor tics include:
- touching objects,
- trunk bending or rotation,
- socially inappropriate movements,
- obscene gestures,
- imitation of other peoples' gestures.
Simple phonic tics include:
- clearing throat,
- meaningless sounds or utterances.
Complex phonic tics include:
- complex and loud sounds,
- phrases out of context,
- phrases with obscenities,
- repetition of other person's phrases.
Tics might be transiently suppressed by the individual. Additionally, tics may also be suppressed with tasks that require concentration or by distraction. For example, when a child with tics is watching TV or playing video games, the tics maybe suppressed to a minimum.
This characteristic could lead a non-informed observer to believe that the movements are fully under the child's control. However, this is not the case. Even though the patient has some control, prolonged suppression of tics is usually associated with an unpleasant sensation that is relieved only by the tic. Voluntary suppression of tics is a very taxing task for the person with Tourette's syndrome.
Most individuals with Tourette's syndrome perceive some inner body sensation before the tic occurs. For example he/she may feel a burning or an itching of the eyes that is suppressed by moving the eyes, or a tickling in the throat that is relieved only by "clearing the throat". After this subjective feeling, the patient may need to repeat the tic several times until the unpleasant sensation is gone. In some individuals a non-well defined urge precedes the tic.
Stress, anxiety, fatigue and boredom can worsen the symptoms of a person with Tourette's syndrome.
Moreover, tics have a wax and wane quality. Tics have a tendency to cluster during certain hours and under certain circumstances rather than being present evenly throughout the day. Also, tics might not be seen for hours after a severe cluster.
Additionally, the quality, frequency and type of tics change during the evolution of the disease. Tics that were once frequently seen are suppressed and exchanged for other tics.
Usually, the first signs of disease start in childhood. The tics may increase in frequency and severity in adolescence and, even though the condition is chronic, there is a tendency to improve in adulthood. By age 18, 50 % of patients with Tourette's syndrome might be symptom-free; however, some individuals might see a recurrence of the symptoms later in life. Usually, simple motor tics are seen at an early age and precede verbal tics. Also, complex tics are first seen later in life.
Other Associated Conditions
Associated conditions have been reported in almost half of the children with Tourette's syndrome. The most common are attention deficit hyperactivity disorder (ADHD) and obsessive compulsive disorder (OCD). Both of these disorders can be observed before school age. It is not clear why these conditions are so frequently present. It is probable that they share a common pathological mechanism in the brain.
In addition, individuals with Tourette's syndrome may also have depression, anxiety, and other behavioral problems. In some cases, this may be attributed to being perceived as different or being rejected by peers.
Developmental disability is not a feature of Tourette's syndrome, however the presence of ADHD may disrupt learning, resulting in poor grades.
Our present understanding is that Tourette's syndrome is a biological disorder of the brain, but the exact reasons for of the tics and the associated disorders that are often seen in persons with Tourette's syndrome are not clear.
Fortunately, Tourette's syndrome is not a fatal condition; hence, there are very few possibilities of performing autopsies on individuals with Tourette's syndrome. In the few autopsies reported most of the abnormalities were seen in an area deep in the brain, thebasal ganglia, which is known to be strongly associated with the control of movement.
This is an expected finding since this area of the brain is known to be abnormal in other conditions that are also associated with movement disorders not related to Tourette's syndrome. Recently, MRI studies of the brain in persons with Tourette's syndrome also have shown some abnormalities in this area of the brain.
There is a familial incidence of Tourette's syndrome. First-degree relatives of persons with Tourette's syndrome more frequently have tics and obsessive compulsive disorders or attention deficit hyperactivity disorder (ADHD) than the general population.
Also, twin studies have shown that identical twins (monozygotic twins) are five times more likely to both have Tourette's syndrome than in twins that are not identical (dizygotic twins). These observations suggest an autosomal dominant inheritance of the condition with variable penetrance.
However, in spite of this strong evidence of genetic involvement, at the present time, no gene has been identified as related to Tourette's syndrome. Moreover, other factors are certainly also responsible for the symptoms. For example, the severity of the syndrome in affected identical twins is not necessarily the same. For example, Tourette's syndrome is more severe in the twin who experienced greater perinatal complications.
The observation of tics developing after streptococcal infections motivated clinical trials to look at the role of autoimmune disorders as a cause of Tourette's syndrome. It is known that streptococcal infections can trigger, in certain individuals, autoimmune disorders that can attack and damage the basal ganglia, resulting in Sydenham chorea.
This is a movement disorder characterized by multiple abnormal movements, including tics, as well as other behavioral issues such as obsessive compulsive disorders, which are also seen in people with Tourette's syndrome.
Also clinical trials have looked at the role that pediatric autoimmune neuropsychiatric disorders associated with streptococcal infections (PANDAS) may play in the development and prognosis of Tourette's syndrome, but, presently, this is only a hypothesis and has not been proven.
Finally studies are inconclusive about the possible association between exposure to stimulants methylphenidate (Ritalin, Ritalin SR, Ritalin LA), amphetamines (Adderall) and certain other medications lamotrigine (Lamictal) and the precipitation of Tourette's syndrome.
It has also been found that Tourette's syndrome is more common in boys than in girls by a ratio of five to one.
Tourette's syndrome has been described in people of many ethnic backgrounds. At the present time there is no indication that Tourette's syndrome is more frequent in any particular ethnic group.
The treatments that are available are all symptomatic, meaning that they are directed at improving the symptoms rather than eliminating the cause of the disease. No curative or preventative treatment is available.
The goal of the treatment should be to help the patient to live a normal life, with the understanding that, at the present time, the treatments available do not suppress all of the symptoms. Since associated conditions may be more disabling that the tics, the treatment should be tailored to the needs of the particular individual and directed to the most troublesome symptoms.
It should be noted that as Tourette's syndrome is a chronic condition and the symptoms naturally wax and wane, any apparent success of a treatment might be an expression of the natural evolution of the disease more so than the effect of the treatment.
In most instances treatment with medication is not necessary. However, if the severity of the symptoms affects the patient's social integration or the tics are very painful or result in self-injurious behavior, then a trial with medication might be indicated.
Generally, medications should be combined with behavioral approaches to decreasing stress and anxiety.
Several treatment options, including pharmacological and non-pharmacological therapies, are presented below.
Treatment of Tics
The most effective medication for the suppression of tics is haloperidol (Haldol), a dopamine blocker medication originally approved for the treatment of psychiatric disorders. Unfortunately, this medication may result in a serious complication, tardive dyskinesia, which might be more disabling that the tics. Even though this complication has not been described in persons with Tourette's syndrome, the use of haloperidol is limited to the most serious cases.
Other medications in this group such as olanzapine (Zyprexa), risperidone (Risperdal), ziprasidone (Geodon), or aripiprazole (Abilify) might have less side effects than haloperidol (Haldol), but there is not enough clinical experience with these drugs in Tourette's syndrome, so their use is very limited.
Clonidine (Catapres) and guanfacine (Tenex), first introduced as cardiovascular medications, are effective in the treatment of tics and also in decreasing anxiety. These medications may be an acceptable first option in some patients.
Clonazepam (Klonopin) belongs to a group of medications (the benzodiazepines) that were first used because of their sedative and relaxing effect. From this group clonazepam can be effective in decreasing some tics and also in helping with anxiety disorders. Side effects such as sedation, weakness, and tiredness might be a limiting factor.
Botulinum toxin injections might be useful for certain disabling localized tics. The effect may only last for a few months, and repeated treatments might result in tolerance, rendering the drug ineffective after several applications.
Although psychological problems do not cause Tourette syndrome, such problems may result from Tourette syndrome. Psychotherapy can help the person with Tourette syndrome better cope with the disorder and deal with the secondary social and emotional problems that sometimes occur.
More recently, specific behavioral treatments that include awareness training and competing response training, such as voluntarily moving in response to a premonitory urge, have shown effectiveness in small controlled trials. Larger and more definitive NIH-funded studies are underway.