Tourette Syndrome Flashcards
When did tic illness disappear and reappear?
In the 1930s, then rediscovered in 60/70s
What drug was found to be helpful for Tics in the 60s?
Haloperidol
What symptoms were observed in the Jumping Frenchmen of Maine, an early description of TS in 1880?
▪️Excessive startle
▪️Echolalia (involuntary repetition of someone’s sounds)
▪️Echopraxia (involuntary repetition of someone’s actions)
▪️Coprolalia
▪️Forced obedience
What is the main DMS-V diagnostic criteria for Tourette syndrome?
Both multiple motor and one or more vocal tics present at some time during the illness, not necessarily together.
Tics may wax and wane in frequency but persist for more than 1 year.
According to the DSM-V, when must the onset of tics occur?
Before 18
What other conditions may cause tic-like presentations?
▪️Substance abuse (e.g. cocaine)
▪️Huntington’s disease (chorea)
▪️Postviral encephalitis
When do tics normally present in Tourette’s?
Age 5-7
How do tics evolve in adolescence?
They typically improve
What are tics?
▪️Semi-purposeful, brief movements or vocalisations.
▪️Relief from an premonitory sensation (urge)
▪️Range from simple gestures to complex stereotypies
▪️Suppressible but usually irresistible
How do tics present over time?
They wax and wane, critically dependent on the environment and what the individual is doing
E.g. may subside when driving or listening to music, but be made worse by stress
At what age is Tourette syndrome usually worst before remission?
Age 10-11
What are the main issues with understanding the long term course of tics?
▪️Lacks long term prospective data
▪️Elderly patients are rare
▪️Inaccurate self-assessment
▪️Adult clinic attendees represent more severe cases
▪️Increased mortality, suicide, and cardiovascular risk
▪️Tics may still be present but disability diminished
What are the most common comorbidities in TS?
▪️ADHD (60%)
▪️OCD (32%)
(12% have just tics)
What features are associated with comorbidity in TS?
▪️Anger control problems
▪️Sleep difficulties
▪️Coprolalia
▪️Self injurious behaviour
What are the four main types of tic disorder?
▪️Tourette syndrome
▪️Chronic vocal tics
▪️Chronic motor tics
▪️Transient tic disorder
Which type of tic disorder shows the greatest comorbidities?
Tourette syndrome
Which type of tic disorder shoes the least comorbidities?
Transient tic disorder
Why does OCD and TS show a high rate of comorbidity?
The symptoms and genetics show a high degree of overlap
(e.g. touching, counting, ordering, checking, obsessions)
What other psychiatric disorders show a high burden in TS and why might this be?
Mood disorders, anxiety disorders, and disruptive behaviour disorders
Likely secondary effects of the TS
What is the estimated prevalence of TS?
0.3-0.7% (3.2% with liberal criteria)
BUT this has likely increased follwiing the pandemic
What perinatal exposures may increase risk of TS?
▪️Poor maternal weight gain
▪️Alcohol
▪️Cannabis
▪️Parity (no. of times mother has given birth)
NOT birth weight or smoking
What pre and post-natal factors may increase risk of TS?
Maternal anxiety and depression
How does the demographic of functional tic-like movements differ from TS?
Predominantly seen in young girls and young women
Describe the genetic unpinning of TS.
▪️Likely complex, with multiple interacting genes and environmental factors building vulnerability.
▪️2 possible very rare single gene mutations
▪️NRXN1 may be first confirmed susceptibility gene
▪️Possible epigenetics
What brain area shows subtle atrophy in TS?
The striatothalamo-cortical system (basal ganglia)
What is hypothesised to cause the structural problems seem in the basal ganglia?
Migration abnormalities in development possibly lead to regulatory interneurons getting stuck in the GPi, reflected by the greater density in this area at the detriment of the GPe, putamen, and caudate
Generally, the neurobiology of TS is _____________.
Inconclusive
What neurotransmitter pathway may be implicated in TS?
Dopamine
What is thought to influence the timing of tics?
Cortical/environmental influences and phasic activity in sensorimotor loops
What is thought to influence the location of a tic?
Basal ganglia somatopy
What neurotransmitters are thought to be implicated in TS and why?
▪️Dopamine
▪️GABA
▪️Glutamate
Because neuroleptics help symptoms
Is TS related to streptococcal infection and neuro-immunology?
Not sure, not yet found an association
What neuropsychological findings have been observed in people with TS?
▪️Normal IQ but increased LD
▪️Enhanced cognitive control - oculomotor switching and response inhibition
▪️Rorschach “perculiar personality style”
What are the main treatments available for tics?
▪️Cognitive behavioural
▪️Medication
▪️Botox injection
▪️DBS
(and non-invasive brain stimulation?)
How can Exposure and Response Prevention therapy be used for tics?
Train individuals to tolerate the urge more by practicing not acting on it for increasing periods of time until the tic subsides
Stimulus = premonitory urge
Response = tic
How can Habit Reveral Training (HRT) be used for tics?
Train individuals to block a tic with an opposing movement when they feel the tic coming
E.g. if the tic is to tilt the head back, learn to tilt it forward first
What is CBIT?
Comprehensive Behavioural Intervention for Tics
What are the main components of CBIT?
- Psychoeducation and awareness training around the tics
- Habit reversal training - competing behaviours
- Functional intervention - identifying and adapting exacerbators and relieving factors
(May also include a reward system/contingency management, and relaxation training)
What are the main limitations of CBIT?
▪️ Expensive
▪️ Effect size similar to medication - 50% have no meaningful response
What are the main problems associated with treating Tourette’s?
▪️ Unclear pharmacological target - might be associated anxiety more than the tics?
▪️ Unclear duration of treatment needed
▪️ Condition is highly variable (waxing and waning vs situational)
▪️ Difficult to measure outcome
▪️ Comorbidities?
▪️ Variability of impact particularly on QoL
▪️ Lack of evidence for medication - many low powered small studies
According to the AAN Practice Guideline, which intervention for TS has the highest confidence in the evidence?
CBIT
According to the AAN Practice Guideline, which interventions for TS have moderate confidence in the evidence?
▪️ Aripiprazole
▪️ Clonidine
▪️ Botox
According to the AAN Practice Guideline, which interventions for TS have low confidence in the evidence?
▪️ Pimozide
▪️ Topiramate
According to the Health Technology Assessment Systematic Review, what medication classes appear to have the best short-term meaningful benefit for tics?
▪️ Antipsychotics
▪️ Noradrenergic drugs
What drugs can be used to treat tics in TS?
▪️ Neuroleptics, particularly aripiprazole, risperidone and sulpiride
▪️ Clonidine/guanfacine (adrenergic)
▪️ Tetrabenazine (failed recent trial)
▪️ Botox
What medications may be considered for comorbid ADHD in TS?
▪️ Clonidine
▪️ Stimulants (e.g., methylphenidate)
▪️ Atomoxetine
What medications may be considered for comorbid OCD or depression in TS?
SSRIs
What must be monitored when prescribing neuroleptic medications?
▪️ Weight
▪️ ECG
▪️ Lipids
▪️ Glucose
▪️ Prolactin
▪️ Extrapyramidal symptoms
How might DBS be used to treat TS?
Unclear target for electrodes but likely thalamic or GPi
Possibly improve tics but not urges
What issues are associated with DBS for treatment in TS?
▪️ Lack of strong evidence base - all uncontrolled cases, problems with blinding
▪️ Unclear target
▪️ Not to be performed in children
▪️ High risk of adverse effects
What are the benefits of non-invasive brain stimulation, such as TMS or tDCS, for use in TS?
▪️ Altered synaptic excitability and intracortical inhibition with increased gain of sensory input to motor areas
▪️ Increased cortico-cortical coherence
▪️ Possible help with abnormal plasticity
What non-invasive brain stimulation techniques might be beneficial in TS?
▪️ TMS
▪️ tDCS
▪️ Peripheral nerve stimulation
What are the main limitations of non-invasive brain stimulation techniques for TS?
▪️ Current results are mixed and purely investigational
▪️ Not very practical long-term
▪️ Unclear targets/underlying mechanism
How might a smartwatch be adapted for management of TS?
▪️ Rhythmic median nerve stimulation at 12Hz
▪️ Entrains brain sensorimotor rhythms/coherence (alpha) to suppress tics
(Some describe remarkable short-term benefit but unclear about long-term yet)
