What is Tourette Syndrome?
The Gilles de la Tourette syndrome (TS) is a chronic neuropsychiatric disorder that involves involuntary movements and vocal noises, called tics, which come and go. In addition to tics, individuals with TS often have a variety of other conditions which can include obsessive-compulsive disorder (OCD), attention deficit hyperactivity disorder (ADHD), learning difficulties and sleep abnormalities. Although these conditions are not required for the diagnosis of TS, their impact on the patient may be more significant than the tics themselves. There is no diagnostic laboratory test. Diagnoses are based on the history and clinical examination of the patient.
Tics, the essential component of the syndrome, are manifested in a variety of forms with different durations and degrees of complexity. No two patients have exactly the same symptoms.
- Simple motor tics are brief rapid movements that often involve only one muscle group, e.g., eye blink, head jerk or shoulder shrug.
- Complex motor tics are abrupt movements that involve either a cluster of simple movements or a more coordinated sequence of movements. Complex motor tics may be non-purposeful (facial or body contortions), or appear to be more purposeful but actually serve no purpose (touching, smelling, jumping, obscene gestures), or have a dystonic character.
- Simple vocal tics include such sounds as grunting, barking, yelping and throat clearing.
- Complex vocal tics include syllables, phrases, echolalia (repeating other people's words), palilalia (repeating one's own words) or coprolalia (obscene words).
Diagnostic criteria for Tourette syndrome
The formal criteria for Tourette Syndrome provided by The Tourette Syndrome Classification Study Group includes:
- the presence of multiple motor and at least one vocal tic (not necessarily concurrently)
- a waxing and waning course with tics evolving in a progressive manner
- the presence of tic symptoms for at least one year
- the onset of symptoms before age 21
- the absence of a precipitating illnesses (e.g., encephalitis, stroke, or degenerative disease) or medication
- the observation of tics by a knowledgeable individual
Coprolalia, one of the most socially distressing symptoms of tic disorders, is not a diagnostic criterion nor is there a requirement for comorbid neurobehavioral problems. Accurate separation of chronic tic disorders from TS is essential for researchers, but has little relevance for outcome or treatment.
Tics have a waxing and waning course and fluctuation of symptoms is expected. In most patients, motor and vocal tics remain mild but require long-term follow up. Although TS was originally proposed to be a lifelong disorder, its course may be quite variable with some patients having a spontaneous remission or marked improvement independent of the use of tic-suppressing medication. In discussions of outcome, we use the "rule of thirds" (1/3 disappear, 1/3 are better, and about 1/3 continue). To date, there are no good prognostic indicators, however, to assist in determining into which group a patient will ultimately fit as he/she gets older.
The list of associated problems in TS continues to increase. It has become clear that the presence of psychopathology is more pervasive than was previously estimated. The presence of a child with TS in the home, especially one with behavioral comorbidity, can have a significant negative effect on the parents. Several common comorbid problems include obsessive-compulsive disorder (OCD), attention deficit hyperactivity disorder (ADHD), mood disorder, episodic outbursts, and academic difficulties:
OCD - The incidence of obsessive-compulsive behaviors (OCB) in TS is typically reported to be in the range of 40-50 percent Some studies report up to 60-89 percent. Obsessive behaviors generally emerge several years after the onset of tics, usually during early adolescence. Behaviors can include a need for order or routine and a requirement for things to be symmetrical or "just right." Thus, compulsions typically involve arranging, ordering, hoarding, touching, tapping, rubbing, counting, checking for errors and evening-up rituals (performing activities until things are symmetrical or feel/look just right). It has been suggested that tics and compulsions represent a clinical spectrum in TS with symptoms sharing many overlapping features.
ADHD - Attention deficit hyperactivity disorder is characterized by impulsivity, hyperactivity and a decreased ability to maintain attention. The disorder is common in TS patients and is reported to affect about 50 percent of referred TS cases. ADHD typically begins between ages four and five and usually precedes the onset of tics by two to three years in TS patients.
Depression and Anxiety - Some investigators believe depression positively correlates with earlier onset and longer duration of tics, whereas others find no correlations between depression and the number of tics.
Rage Attacks - Rage attacks and difficulties with aggression have been described in patients with TS. Whether these problems are etiologically related to TS or other comorbid conditions is under review.
Academic Difficulties - Severe tics, psychosocial problems, ADHD, OCD, learning disabilities, and medications can result in poor school performance in children. Individuals with TS typically have normal intellectual functioning, although there may be executive dysfunction, discrepancies between performance and verbal IQ, impairments of visual perceptual achievement or a decrease in visual-motor skills.
The first step is a careful evaluation of all potential problems, including an analysis of tics, documentation of comorbid conditions, assessment of problem severity and determination of resulting impairment. The next step is to determine the priority of symptoms, that is, in conjunction with the patient, family, and school personnel, the physician must determine whether tics or associated problems represent the greatest handicap. Just because a symptom exists, tics or otherwise, is not an adequate reason to initiate pharmacotherapy. Medications should be targeted and reserved for only those problems that are functionally disabling and not remediable by non-drug interventions. Lastly, it should be recognized that the treatment of a child with TS requires a chronic commitment and at times a comprehensive multidisciplinary approach.
Tics - Patients considering behavioral or pharmacological treatments should be aware of the natural waxing and waning of tics, large placebo response and the influence of psychopathologies on outcome. A variety of nonpharmacologic behavioral treatments (conditioning techniques, massed negative practice, awareness training, habit reversal, relaxation training, biofeedback, and hypnosis) have been proposed as alternative therapeutic approaches, but few have been adequately evaluated. To date, there is no cure for tics and all pharmacotherapy must be considered symptomatic therapy. If tic-suppressing medication is indicated, a two-tiered approach is recommended: 1) non-neuroleptic drugs for milder tics, and 2) typical/atypical neuroleptics for more severe tics. The goal of treatment is not complete suppression of all motor and phonic tics, but to reduce them to a level where they no longer cause a significant psychosocial disturbance
ADHD - Similar to treatment in any child with this problem, a variety of behavioral and educational approaches should be implemented before pharmacotherapy is considered. Psychostimulant medications are generally regarded as the treatment of choice for ADHD and their use in children with TS is not contraindicated. Alternative medications for the treatment of ADHD symptoms in children with TS include clonidine, guanfacine, atomoxetine, desipramine, and nortriptyline. In the occasional situation where a stimulant is required for attendance in school or performance at work and tics remain constant, stimulants and tic-suppressing medications are used simultaneously
OCD - In TS patients with OCD, pharmacologic and cognitive-behavioral therapy should be considered. Several selective serotonin reuptake inhibitors may be beneficial.