What Is Tourette Syndrome?
Tourette syndrome is a relatively common and complex neurobehavioral disorder characterized by motor and vocal (phonic) tics. Tics are abrupt, rapid, brief, repetitive behaviors that may resemble aspects of normal behavior, except in their intensity, frequency, and timing. Examples of common motor tics include eye blinking, eye deviation, facial grimacing, neck popping, head jerking, and shoulder shrugging. Tics may also cause noise or sound as air is forced through the nose and throat ("vocal" or "phonic" tics). Sniffing, coughing, grunting, guttural maneuvers, inhaling, shrieking, sniffing, and squealing are among the most common phonic tics. Some tics are described as "complex" and may involve the integration of learned, sequenced movements (e.g. touching, tapping, jumping, gestures) or complex vocalizations (e.g. repeating a syllable, word, or phrase). An example of a complex vocal tic is shouting of profanities or obscenities, so called coprolalia, but this is actually present in less than a third of all patients. Tourette syndrome is often accompanied by obsessive-compulsive disorder, attention deficit-hyperactivity disorder, poor impulse control, and other behavioral problems.
Tourette syndrome typically begins in childhood and can vary between patients, with symptoms ranging from mild to disabling. Also, people with Tourette syndrome often find that their own symptoms fluctuate in severity and frequency over the course of their childhood. Tics can often be suppressed for periods of time, but this may cause discomfort and fatigue. Many patients "grow out of it" and are free of tics by their late teens or early twenties.
Tourette syndrome in childhood has been estimated at 0.5-1 percent, although this proportion differs between scientific studies. It is a well-known fact that males are more commonly affected than females (3-4:1). Tics typically start around the age of 4-6 years and reach their peak severity age 10-12 years. Usually, tic severity then decreases as the patient grows older, however some patients will continue to suffer from tics into adulthood.
The diagnosis depends on a careful evaluation of the patient's symptoms and signs by an experienced clinician. Educational efforts by the Tourette Syndrome Association (see appendix at the bottom of this page) and scientific programs directed to physicians, educators and the general public have increased awareness about Tourette syndrome. In addition, a growing public attention has been drawn to this condition by the media. As a result of this improved awareness, self-referral rate of patients has increased and the correct diagnosis is made earlier than in the past. Many patients, however, still remain undiagnosed or their symptoms are wrongly attributed to "habits," "allergies," "asthma," "dermatitis," "hyperactivity," "nervousness" and many other conditions.
Motor tics are abrupt, brief, rapid, repetitive, often transiently suppressible, movements that may fluctuate in distribution and severity. Tics are often exacerbated by stress and by suggestion. Common motor tics include eye blinking, eye deviation, facial grimacing, neck popping and/or stretching, and shoulder shrugging. Tics may also cause noise or sound by moving air through nasal and oropharyngeal passages (vocal or phonic tics). Sniffing, coughing, grunting, guttural maneuvers, inhaling, screaming, sniffing and squealing are among the most common phonic tics. Simple tics involve repetitive movement of one muscle group such as shoulder shrugging, eye blinking, or neck popping. Complex motor tics include coordinated motor behaviors such as touching, tapping, jumping, skipping when walking, or socially inappropriate gestures (copropraxia). Coprolalia, manifested by shouting of obscenities or profanities, is probably the most over-emphasized symptom of Tourette syndrome, and is actually present in only about one-third of all patients. Other complex phonic tics include palilalia (repetition of the last syllable, word or phrase in a sentence), or echolalia (repetition of someone else's words or phrases). In contrast to a popular belief, motor and phonic tics may persist during all stages of sleep.
Tics are frequently preceded by premonitory sensations described by patients as a need to stretch the muscle, increased tension or discomfort, or an urge to have to tic until it "feels just right." The latter premonitory sensation is particularly interesting in that the "just right" phenomenology may be integrated into compulsive behaviors such as constant rearranging, piling and lining up in a symmetrical pattern, excessive checking, washing or ritualistic house cleaning. Frequently Tourette syndrome patients engage in activities until it looks "just right" or tic until it feels "just right." The clinician must consider which component of Tourette syndrome to medicate; the obsession that triggers the tic, the tic itself, or both. Tourette syndrome children volitionally exert their energy to suppress their tics in order to avoid embarrassment or social ridicule. These children may have more tics when they return home from school and are relaxed.
In addition to tics, Tourette syndrome is commonly associated with ADHD and Obsessive-Compulsive Disorder (OCD) (60-90 percent and 40-60 percent of Tourette syndrome patients, respectively), as well as other behavioral problems such as poor impulse control, anxiety, mood and conduct disorders, and self-injurious behavior. These behavioral symptoms may contribute to poor academic, social, and work adjustment and productivity and for many patients, they are more concerning and debilitating than the motor tics.
The cause of Tourette syndrome is yet unknown, but the disorder appears to be inherited in the majority of patients. Studies have found that the genetic susceptibility is inherited in many patients from both parents - so called bilineal transmission. Typically, the mother manifests features of OCD, the father may have a history of childhood tics and/or ADHD and the child has a more complete syndrome manifested by a combination of tics, OCD, ADHD, poor impulse control and other behavioral co-morbidities. The clinical expression of the genetic defect varies from one individual to another, fluctuations in symptoms are seen within the same individual, and different manifestations occur in various family members.
Treatment for Tics
The goal of treatment should not be to completely eliminate all the tics, but to achieve a tolerable suppression. Although a variety of behavioral and alternative therapies have been tried, most clinicians believe that the treatment of choice for reducing the frequency and severity of tics involves the use of medications that act by blocking dopamine receptors or deplete dopamine. Although these neuroleptic (dopamine receptor blocking) drugs, such as haloperidol (Haldol), risperidone (Risperdal), pimozide (Orap) and fluphenazine (Prolixin) have proven efficacy in reducing tics, they may be associated with a variety of side effects. These include gastrointestinal upset, sedation, restlessness and weight gain. Periodically monitoring the ECG is recommended in patients taking pimozide. Acute dystonic reaction such as face and neck spasms, lock jaw or involuntary eye deviation may occur with all these drugs, but this side effect can be effectively reversed with anticholinergic medications such as benztropine (Cogentin) or diphenhydramine (Benadryl). Rarely, dopamine blocking agents may cause involuntary, repetitive movements typically involving the lower face and mouth, called tardive dyskinesia. Other antidopaminergic drugs such as tetrabenazine (Xenazine) and the newer drugs deutetrabenazine (Austedo) and valbenazine (Ingrezza) may be effective in treating tics without the risk of tardive dyskinesia. Other drugs occasionally found useful in the treatment of tics include clonidine (Catapres), guanfacine (Tenex) and clonazepam (Klonopin). The class of drugs known as atypical neuroleptics, such as clozapine (Clozaril), olanzapine (Zyprexa), quetiapine (Seroquel), ziprasidone (Geodon) and aripiprazole (Abilify) may also be useful in treating tics and some associated behavioral problems. Another approach to the treatment of tics is the use of botulinum toxin (Botox) injections in the area of the most problematic tic. Botulinum toxin injections are safe and effective in reducing the severity and frequency of tics without the side effects of systemic medications. Depending on the site of injection, the most common side effects include transient ptosis (drooping of the eye), neck weakness, and hypophonia. Finally, there has been a growing public interest in cannabinoids for the treatment of Tourette syndrome (and other medical disorders), although the evidence is still lacking.
Educating parents, teachers and school administrators as well as healthcare professionals is crucial in early recognition of symptoms, confirming a diagnosis, and initiating appropriate treatment. Because of the broad range of neurological and behavioral manifestation and varying severity, therapy of Tourette syndrome must be individualized and tailored specifically to the needs of the patient. The most troublesome symptoms, such as tics, OCD, ADHD and impulse control problems, should be targeted first, but many patients may require more than one medication, depending on the complexity and severity of the symptoms. Medications should be instituted at low doses and titrated gradually to the lowest, but effective, dosage and tapered during non-stressful periods (e.g. summer vacations). Another important principle of therapy in Tourette syndrome is to give each medication and dosage regimen an adequate trial. This approach will avoid needless changes made in response to variations in symptoms during the natural course of the disease. Optimal management of Tourette syndrome requires the integrated experience of various disciplines of educators, physicians, allied healthcare professionals, psychologists and social workers. When all medical therapies fail and the patients continue to be disabled by severe, self-injurious tics or OCD, surgical therapy using deep brain stimulation (DBS) may be considered as a final option.