- Last edited on May 17, 2021
Tic Disorders (Tics) and Tourette's
Primer
Tics are sudden, rapid, recurrent, non-rhythmic motor movements or vocalizations. Individuals with tics experience a feeling of a mounting inner tension or urge (known as a premonitory urge), which is transiently relieved by tic expression. Tics will wax and wane with time, and can be worsened with stress, fatigue, or excitement. Although tics can include almost any muscle group or vocalization, certain tic symptoms, such as eye blinking or throat clearing, are more common. Tics are generally experienced as “involuntary” but are usually temporarily suppressible. Tourette’s Disorder is the most “famous” of the tic disorders.
Epidemiology
- In one study, the prevalence of Tourette's was reported to be 0.5%.[1] Tourette's affects males more than females (ratio of 4:1).
Prognosis
- Tic severity peaks by age 11, and there is a gradual decrease in symptoms afterwards for most (around 80%).
Comorbidity
- The treatment of comorbid conditions in tic disorder is important
- About 35% of individuals will also have co-morbid obsessive-compulsive disorder (while up to 90% will have obsessive-compulsive symptoms)
- OCD symptoms also tend to be different when there are co-morbid tics. For example, there may be more (1) sensory phenomena, (2) sexual, violent, religious and symmetry themes, and “tic-like” compulsions (e.g. - touching, taping, rubbing, blinking, and staring).[2]
- Other comorbid conditions include: ADHD (50%), autism spectrum disorder (10%), and a mood, anxiety, or disruptive behaviour (30%).[3] Only about 10% will not have any comorbidity.[4]
Risk Factors
Classification and Terminology
Tic disorders can be classified in to 4 disorders:
- Tourette’s disorder
- Persistent (chronic) motor or vocal tic disorder
- Provisional tic disorder
- Other specified and unspecified tic disorders
Remember the Diagnostic Hierarchy
Tic disorders are hierarchical in order - once a tic disorder at one level of the hierarchy is diagnosed, a lower hierarchy diagnosis cannot be made (Criterion E). The escalating hierarchy of diagnosis is (1) other specified and unspecified tic disorders (lowest) → (2) provisional tic disorder → (3) persistent motor or vocal tic disorder → (4) Tourette’s disorder (highest).Simple and Complex Tics
Tics can be either simple or complex:
- Simple motor tics are of short duration (i.e., milliseconds) and can include eye blinking, shoulder shrugging, and extension of the extremities.
- Simple vocal tics include throat clearing, sniffing, and grunting often caused by contraction of the diaphragm or muscles of the oropharynx.
- 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 tics can appear purposeful, such as a tic-like sexual or obscene gesture (copropraxia) or a tic-like imitation of someone.
Does Someone With Tics Always Swear?
Coprolalia, the involuntary swearing or utterance of obscene words or socially inappropriate and derogatory remarks, is a common popular culture assumption of what tics look like. However, coprolalia has a point prevalence of only 15-20% of population (i.e. - 15-20% will have coprolalia at some point, and not consistently).DSM-5 Diagnostic Criteria
Tourette’s Disorder
Criterion A
Both multiple motor and 1 or more vocal tics have been present at sometime during the illness, although not necessarily concurrently.
Criterion B
The tics may wax and wane in frequency but have persisted for more than 1 year since first tic onset.
Criterion C
Onset is before age 18 years.
Criterion D
The disturbance is not attributable to the physiological effects of a substance (e.g. - cocaine) or another medical condition (e.g. - Huntington’s disease, post-viral encephalitis).
Persistent (Chronic) Motor or Vocal Tic Disorder
Criterion A
Single or multiple motor or vocal tics have been present during the illness, but not both motor and vocal.
Criterion B
The tics may wax and wane in frequency but have persisted for more than 1 year since first tic onset.
Criterion C
Onset is before age 18 years.
Criterion D
The disturbance is not attributable to the physiological effects of a substance (e.g. - cocaine) or another medical condition (e.g. - Huntington’s disease, post-viral encephalitis).
Criterion E
Criteria have never been met for Tourette’s disorder.
Specifiers
Specify if:
- With motor tics only
- With vocal tics only
Provisional Tic Disorder
Criterion A
Single or multiple motor and/or vocal tics.
Criterion B
The tics have been present for less than 1 year since first tic onset.
Criterion C
Onset is before age 18 years.
Criterion D
The disturbance is not attributable to the physiological effects of a substance (e.g. - cocaine) or another medical condition (e.g. - Huntington’s disease, post-viral encephalitis).
Criterion E
Criteria have never been met for Tourette’s disorder or persistent (chronic) motor or vocal tic disorder.
Examples of Complex and Simple Tics
Simple vocal tics include:- Throat clearing
- Sniffling
- Squeaking
- Grunting
- Sounds like “eep!”
Complex vocal tics are:
- Linguistically meaningful sounds
- Sentences like “Oh boy now you've done it!”
- Swearing
- Echolalia
- Palilalia
Comparison of Tic Disorders
Comparison
| Tourette's | Persistent Motor or Vocal Tic Disorder | Provisional Tic Disorder | |
|---|---|---|---|
| Type of Tics | Multiple motor AND at least 1 vocal | Motor OR Verbal | Motor AND/OR Verbal |
| Length | > 1 year | > 1 year | < 1 year |
| Age of onset | Before age 18 | Before age 18 | Before age 18 |
Differential Diagnosis
- Substance-induced tics (e.g. - cocaine)
- Cocaine use is known to cause either temporary or permanent tics.[5]
- Abnormal movements that may accompany other medical conditions and stereotypic movement disorder
- Motor stereotypies are egosyntonic, involuntary rhythmic, repetitive, predictable movements that appear purposeful but serve no adaptive function or purpose. Stereotypies include repetitive hand waving/turning, arm flapping, and finger wiggling. There is an earlier age of onset (younger than 3 years), longer duration (seconds to minutes), constant fixed forms, and lack of a premonitory urge. Stereotypies are exacerbated when the individual is engrossed in an activity and diminish with distractions (e.g. - name called or touched). Tics, on the other hand, begin around age 7 to 8, can wax and wane, and starts caudally (e.g. - usually with blinking and coughing). Tics can get worse before they ultimately get better, but will diminish with age as puberty progresses.
- Chorea are rapid, random, continual, abrupt, irregular, unpredictable, non-stereotyped actions that are usually bilateral and affect all parts of the body (i.e. - face, trunk, and limbs). The timing, direction, and distribution of movements vary, and movements usually worsen during voluntary action
- Dystonia is the simultaneous sustained contracture of both agonist and antagonist muscles causing a distorted posture or movement of parts of the body. Dystonic postures are usually triggered by voluntary movements and are not seen during sleep.
- Myoclonus
- Myoclonus is characterized by a sudden unidirectional movement that is often nonrhythmic. It may be worsened by movement and occur during sleep. Myoclonus is differentiated from tics by its rapidity, lack of suppressibility, and absence of a premonitory urge.
- Restlessness/fidgetiness
- Compulsions in obsessive-compulsive disorder (OCD)
- Differentiating obsessive-compulsive behaviours from tics canbe difficult. Clues favouring an obsessive-compulsive behaviour include a cognitive-based drive (e.g. - fear of contamination) and the need to perform the action in a particular fashion a certain number of times, equally on both sides of the body, or until a “just right” feeling is achieved. Impulse-control problems and other repetitive behaviours, including persistent hair pulling, skin picking, and nail biting, are more goal directed and complex than tics.
- Medication or substance-induced and paroxysmal dyskinesias
- Paroxysmal dyskinesias usually occur as dystonic or choreoathetoid movements that are precipitated by voluntary movement or exertion and less commonly arise from normal background activity
Treatment
Education
Education and support for the patient's family and school is a first-line treatment.[6] Remember as a clinician to educated families that the natural history of tics is that they wax and wane, which can confound medication treatment. It’s possible the tics will get worse, despite treatment. Take your time.
Accommodating Tics
Accommodations should be made in the individual's environment to make tics for manageable for the patient and the people around them. Examples include:- Asking parents and teachers to accept/ignore minor tics
- Accommodate for other tics where possible by:
- Using objects (rugs, foam) to dampen sounds from motor tics
- Replacing words (saying “shoot” instead of “shit”)
- Work with the child in problem solving
- Allow graceful exits
- Encourage accountability through restoration and reparations
Behavioural
Habit reversal therapy (HRT) is a behavioural treatment used to reduce repetitive behaviours. It is a second line treatment for Tourette's, after providing education about the disorder.[7]
Medications
Pharmacotherapy is primarily with alpha-2 agonists or antipsychotics. Note that rebound hypertension can occur if clonidine is stopped abruptly and not tapered.[8]
Pharmacological Treatment for Tic Disorders
| 1st line | Clonidine 0.05 mg PO daily as a starting dose, and titrate to 0.15 to 0.3mg PO once daily |
|---|---|
| 2nd line | |
| 3rd line | |
| Adjunctive therapy | |
| Not recommended |