Tic Disorders: Symptoms, Diagnosis, and Treatment

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What is a tic disorder?

A tic is a sudden, rapid, nonrhythmic movement or sound that people do repeatedly. Unlike tics, the majority of muscle twitches are isolated occurrences, not repeated actions. Tic disorders are complex, diverse, neurodevelopmental disorders caused by an interplay of genes and environment. Tic disorders comprise four diagnostic categories: Tourette’s disorder, persistent (chronic) motor or vocal tic disorder, provisional tic disorder, and the other specified and unspecified tic disorders. Perhaps the best known of the tic disorders is Tourette disorder, also known as Tourette syndrome.

As many as 1 in 100 people may experience some form of tic disorder, usually before the onset of puberty. Transient tics, which are either sudden motor movements (eye blinking, head jerking, shoulder shrugging) or unexpected vocal sounds (throat clearing, snorting, screeching) are common in childhood, occurring in as many as 33% of boys and 16% of girls in one classroom observation. Motor or vocal tics that persist as long as 1 year are much less common and occur in about 1–4% of children. Prevalence estimates for combined chronic motor and vocal tics (Tourette’s Disorder) vary around 1% of the general population and are up to 10 times more common in males.

The exact cause for tics to occur is not known, though stress and sleep deprivation are thought to play a role. Tic disorders can be managed quite well with treatment and lifestyle changes.

Girl blinking eye
Simple motor tic

Symptoms of Tic Disorders (Sadock, et al., 2017)

The onset of tics is typically between ages of 4 and 6 years. The severity of symptoms is more between ages 10 and 12 years, with a decline in severity during adolescence. Many adults with tic disorders have diminished symptoms.

Patients tend to manifest the same set of tics at any given time, although tics tend to vary in type, intensity, and frequency over a period of time. They may occur multiple times in an hour, then remit or barely be present for ≥ 3 months. Typically, tics do not occur during sleep.

Motor and vocal tics can be simple or complex.

Simple Tics

Simple tics are a very brief movement or vocalization, typically without social meaning (i.e., unrecognizable gestures or words).

Simple motor tics are of short duration (i.e., milliseconds) and can include eye blinking, shoulder shrugging, and extension of the extremities. Simple motor tics can be:

  • Eye blinking
  • Nose twitching
  • Shoulder shrugging
  • Sustained eye closure
  • Tensing of abdominal or limb muscles

Simple vocal tics include throat clearing, sniffing, and grunting often caused by contraction of the diaphragm or muscles of the throat. Simple vocal tics can thus be:

  • Throat clearing
  • Coughing
  • Sniffing
  • Blowing
  • Barking

Complex Tics

Complex tics last longer and may involve a combination of simple tics. Complex tics may appear to have social meaning (i.e., recognizable gestures or words) and thus seem intentional.

Complex motor tics are of longer duration (i.e., seconds) and often include a combination of simple tics such as simultaneous head-turning and shoulder shrugging. Complex motor tics can be:

  • Touching objects or self
  • Hitting or kicking
  • Hand gestures
  • Throwing
  • Squatting or jumping

Complex vocal tics include repeating one’s own sounds or words (palilalia), repeating the last-heard word or phrase (echolalia), or uttering socially unacceptable words, including obscenities, or ethnic, racial, or religious slurs (coprolalia). Thus, complex vocal tics can be:

  • Syllables or words
  • Phrases
  • Swearing
  • Repeating one’s or others’ words
  • Changes in the rate, rhythm, and volume of speech

Stress, excitement, boredom, fatigue, and exposure to heat can make tics worse. Tics are also prominent when the body is relaxed, such as when watching TV.

Observing a gesture or sound in another person may cause an individual with a tic disorder to make a similar gesture or sound. This can be incorrectly perceived by others as purposeful, which can be a problem when that individual is interacting with authority figures (e.g., teachers, supervisors, police).

Tics are experienced as irresistible but can be suppressed for varying periods of time. There is usually a reduction in the frequency and severity of tics during concentration on mental or physical tasks such as reading and while at work or school. Some patients can suppress tics for several hours while engaged in some task, and then experience a bout of tics. Tics rarely interfere with motor coordination. Mild tics rarely cause problems, but severe tics, particularly coprolalia (involuntary vocalization of obscenities – rare), are physically and/or socially disabling.

Tic disorders can present with co-occurring conditions. Before puberty, children with tic disorders are more likely to experience attention-deficit/hyperactivity disorder (ADHD), obsessive-compulsive disorder (OCD), and separation anxiety disorder. Teenagers and adults are more likely to experience major depressive disorder, substance use disorder, or bipolar disorder.

In individuals with mild to moderate symptoms, there may be no distress or impairment in functioning and they may even be unaware of their tics. But even individuals with severe tic disorders may function well, but rarely tend to have impairments in daily functioning. The presence of a co-occurring condition, such as ADHD or OCD, can have a greater impact on functioning.

If tics disrupt functioning in daily activities, it can result in social isolation, interpersonal conflict, peer victimization, inability to work or to go to school, lower quality of life, and psychological distress. Rare complications of Tourette’s disorder include physical injury, such as eye injury (from hitting oneself in the face), and orthopedic and neurological injury (e.g., disc disease related to forceful head and neck movements).

Causes of Tic Disorders

The causes of tic disorders remain unknown.

  • Several neurotransmitters and neuromodulators are thought to play a role, including dopamine, serotonin, and endogenous opioids.
  • Exposure of the fetus to several agents in the womb and during infancy, including hypoxia-ischemia, exposure to androgens, heat, and infectious agents, have been implicated in the causation of tic disorders.
  • The role of stress, given the strong association of tics with anxiety, is also compelling.

Risk factors for tic disorders include:

  • Genetics: Tics tend to run in families, so there may be a genetic basis for these disorders. Multiple vulnerability genes that likely determine the form and severity of tics
  • Sex: Men are more likely to be affected by tic disorders than women.

Diagnosis of Tic Disorders

Diagnosis for any tic disorder is based on the:

  • Presence of motor and/or vocal tics
  • Duration of tic symptoms
  • Age at onset
  • Absence of any known cause such as another medical condition or substance use.

These are the diagnostic criteria for the three main types of tic disorders (American Psychiatric Association, 2013):

Tourette’s Disorder

  • Both multiple motor and one or more vocal tics have been present at some time during the illness, alone or concurrently.
  • The tics may increase and decrease in frequency but have been there for more than 1 year since the onset of first tic.
  • Onset is before 18 years of age.
  • It is not attributable to substance use (e.g., cocaine) or another medical condition (e.g., Huntington’s disease, postviral encephalitis).

Persistent (Chronic) Motor or Vocal Tic Disorder

  • Either single or multiple motor or vocal tics have been present during the illness, but not both.
  • The tics may increase and decrease in frequency but have been there for more than 1 year since the onset of first tic.
  • Onset is before 18 years of age.
  • It is not attributable to substance use (e.g., cocaine) or another medical condition (e.g., Huntington’s disease, postviral encephalitis).
  • Criteria have never been met for Tourette’s disorder.

Provisional Tic Disorder

  • Single or multiple motor and/or vocal tics.
  • The tics have been present for less than 1 year since the onset of first tic.
  • Onset is before 18 years of age.
  • It is not attributable to substance use (e.g., cocaine) or another medical condition (e.g., Huntington’s disease, postviral encephalitis).
  • Criteria have never been met for Tourette’s disorder or persistent (chronic) motor or vocal tic disorder.

For other specified or unspecified tic disorders, the movement disorder symptoms are best characterized as tics but are atypical in presentation or age at onset, or have a known cause.

Treatment of Tic Disorders (Sadock, et al., 2017)

If the tics are mild or moderate and not causing significant distress or impairment, treatment may not be necessary. All that will be needed in such cases is simple, active monitoring.

Indications for treatment of tics include:

  • Physical pain or discomfort
  • Interference with social interactions
  • Impairment in any aspect of educational or occupational functioning

The first-line treatment for mild to moderate tics is cognitive-behavioral intervention. Medications are usually considered only when symptoms are significant, unable to be addressed by psychotherapeutic interventions, and interfere with academic or job performance, peer relationships, social interactions, or activities of daily living. The goal of treatment is not to eliminate tics, but to relieve tic-related discomfort or embarrassment and to achieve a degree of control of tics that allows the patient to function as normally as possible.

Cognitive-Behavioral Intervention

Comprehensive behavioral intervention for tics (CBIT) is now considered first-line treatment for mild to moderate tics when intervention is warranted. It involves habit-reversal therapy or training (HRT). The primary components of CBIT include:

  • Awareness training: This teaches patients to identify the premonitory urges or sensations that typically precede tics, as well as to recognize the situations in which tics are likely to occur.
  • Competing response training: This involves teaching the patient a competing response to the targeted tic to prevent the emergence of the tic. Parents are taught to provide appropriate support and encouragement to the child in practicing the technique at home. Tic substitution (substituting a more socially tolerable tic for a less socially tolerable one) can be useful.
  • Other components are relaxation training, contingency management, social support, and relapse prevention.

Individual, group, and family therapies are supportive adjuncts to behavioral interventions and pharmacotherapy. Specific workplace interventions include structured tasks, organization of tasks into smaller units, flexible time limits, and ample physical space.

Medications

Clonidine (Catapres) is in use for more than two decades for the treatment of Tourette disorder. Clonidine should generally be started at 0.025 mg daily to twice daily for prepubertal children and increased by 0.025 mg every 5-14 days. Adolescents or adults can be started on 0.05 mg daily and increased by 0.05-mg increments to twice-daily dosing. The total daily dose typically is 0.05-0.45 mg. Common side effects include sedation, headache, dry mouth, stomach ache, mid-sleep awakening, and irritability.

Guanfacine (Tenex) may also be efficacious for hyperactivity, impulsivity, and tics. Prepubertal patients are typically started on 0.25 mg daily and increased by 0.25-mg increments every 5-14 days given twice daily; older patients and adults are typically started on 0.5 mg daily and increased by 0.5-mg increments to about 3.0 mg daily. Side effects include sedation, mid-sleep awakening, constipation, and hypotension.

Antipsychotics haloperidol (Haldol) and pimozide (Orap) were the only FDA-approved agents for the treatment of Tourette disorder. However, because of their serious side effects, they are only preferred as third-line or fourth-line agents. They have been largely replaced by newer generation antipsychotics, such as risperidone (Risperdal). Risperidone is equally effective as pimozide and clonidine for tic reduction. Doses are typically in the 1- to 3-mg range. Common side effects include appetite increase, weight gain, lipid and glucose metabolism abnormalities, and sedation. Other similar options include ziprasidone (Geodon), aripiprazole (Abilify) and olanzapine (Zyprexa).

SSRI antidepressants such as fluoxetine (Prozac), paroxetine (Paxil), fluvoxamine (Luvox), citalopram (Celexa), escitalopram (Lexapro), and sertraline (Zoloft) are first-line agents for pharmacological treatment of significant OCD, anxiety disorders, and mood symptoms that frequently accompany tic disorders. Stimulants are first-line agents for the treatment of associated ADHD, followed by atomoxetine.

Surgery

Surgical interventions are reserved for severe and refractory tics that significantly interfere with function and persist into adulthood.

Newer Modalities of Treatment

Transcranial magnetic stimulation involves generating a brief, powerful magnetic field by a small coil positioned over the skull, inducing an electrical current in the brain. This noninvasive approach is an exciting potential future treatment for tics. Neural stem cell transplantation is another proposed treatment for tics, and animal studies are underway.

References

American Psychiatric Association, 2013. Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition. Washington, DC: American Psychiatric Publishing.

Sadock, B. J., Sadock, V. A. & Ruiz, P., 2017. Kaplan and Sadock’s Comprehensive Textbook of Psychiatry. 10th ed. Philadelphia: Wolters Kluwer.

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Summary
Tic Disorders: Symptoms, Diagnosis, and Treatment
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Tic Disorders: Symptoms, Diagnosis, and Treatment
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Tic disorders are complex, diverse, neurodevelopmental disorders characterized by sudden, rapid, repeated, nonrhythmic movement or vocalization.
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DepressionPedia.org
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