GeneHealth - Your precision medicine

Tourette's Disorder

Disease Details

Family Health Simplified

Buy Membership

Description: Tourette's Disorder is a neurological condition characterized by repetitive, involuntary movements and vocalizations called tics.
Type: Tourette's Disorder is a neurological disorder. The genetic transmission is thought to be complex, with both genetic and environmental factors playing roles. It is generally considered to follow a pattern of autosomal dominant inheritance with variable expressivity and incomplete penetrance.
Signs And Symptoms: Tourette's Disorder is characterized by the presence of motor and vocal tics. Signs and symptoms include:

- **Motor Tics**: These are sudden, rapid, recurrent, nonrhythmic movements. Examples include:
- Eye blinking
- Facial grimacing
- Shoulder shrugging
- Head jerking

- **Vocal Tics**: These are sudden, rapid, recurrent vocalizations. Examples include:
- Grunting
- Throat clearing
- Sniffing
- Barking

Tics can vary in frequency and severity and may change over time. They are often exacerbated by stress or excitement and tend to decrease during focused activities.
Prognosis: Tourette syndrome is a spectrum disorder—its severity ranges from mild to severe. Symptoms typically subside as children pass through adolescence. In a group of ten children at the average age of highest tic severity (around ten or eleven), almost four will see complete remission by adulthood. Another four will have minimal or mild tics in adulthood, but not complete remission. The remaining two will have moderate or severe tics as adults, but only rarely will their symptoms in adulthood be more severe than in childhood.Regardless of symptom severity, individuals with Tourette's have a normal life span. Symptoms may be lifelong and chronic for some, but the condition is not degenerative or life-threatening. Intelligence among those with pure TS follows a normal curve, although there may be small differences in intelligence in those with comorbid conditions. The severity of tics early in life does not predict their severity in later life. There is no reliable means of predicting the course of symptoms for a particular individual, but the prognosis is generally favorable. By the age of fourteen to sixteen, when the highest tic severity has typically passed, a more reliable prognosis might be made.Tics may be at their highest severity when they are diagnosed, and often improve as an individual's family and friends come to better understand the condition. Studies report that almost eight out of ten children with Tourette's experience a reduction in the severity of their tics by adulthood, and some adults who still have tics may not be aware that they have them. A study that used video to record tics in adults found that nine out of ten adults still had tics, and half of the adults who considered themselves tic-free displayed evidence of mild tics.
Onset: Tourette's disorder typically has an onset in childhood, with symptoms usually appearing between ages 5 and 10.
Prevalence: Tourette's Disorder: Prevalence

Tourette's Disorder is estimated to affect approximately 1% of the population, with varying degrees of severity. This means about 1 in every 100 people may have Tourette's Disorder.
Epidemiology: Tourette syndrome is a common but underdiagnosed condition that reaches across all social, racial and ethnic groups. It is three to four times more frequent in males than in females. Observed prevalence rates are higher among children than adults because tics tend to remit or subside with maturity and a diagnosis may no longer be warranted for many adults. Up to 1% of the overall population experiences tic disorders, including chronic tics and transient (provisional or unspecified) tics in childhood. Chronic tics affect 5% of children and transient tics affect up to 20%.Many individuals with tics do not know they have tics, or do not seek a diagnosis, so epidemiological studies of TS "reflect a strong ascertainment bias" towards those with co-occurring conditions. The reported prevalence of TS varies "according to the source, age, and sex of the sample; the ascertainment procedures; and diagnostic system", with a range reported between 0.15% and 3.0% for children and adolescents. Sukhodolsky, et al. wrote in 2017 that the best estimate of TS prevalence in children was 1.4%. Both Robertson and Stern state that the prevalence in children is 1%. The prevalence of TS in the general population is estimated as 0.3% to 1.0%. According to turn of the century census data, these prevalence estimates translated to half a million children in the US with TS and half a million people in the UK with TS, although symptoms in many older individuals would be almost unrecognizable.Tourette syndrome was once thought to be rare: in 1972, the US National Institutes of Health (NIH) believed there were fewer than 100 cases in the United States, and a 1973 registry reported only 485 cases worldwide. However, numerous studies published since 2000 have consistently demonstrated that the prevalence is much higher. Recognizing that tics may often be undiagnosed and hard to detect, newer studies use direct classroom observation and multiple informants (parents, teachers and trained observers), and therefore record more cases than older studies. As the diagnostic threshold and assessment methodology have moved towards recognition of milder cases, the estimated prevalence has increased.Because of the high male prevalence of TS, there is limited data on females from which conclusion about gender-based differences can be drawn; caution may be warranted in extending conclusions to females regarding the characteristics and treatment of tics based on studies of mostly males. A 2021 review stated that females may see a later peak than males in symptoms, with less remission over time, along with a higher prevalence of anxiety and mood disorders.
Intractability: Tourette's Disorder, also known as Tourette Syndrome, is not considered intractable. While there is no cure, many individuals experience improvement in their symptoms over time, especially as they transition from childhood into adulthood. Various treatments, including behavioral therapy and medications, can help manage and reduce the severity of tics and associated symptoms.
Disease Severity: Tourette's Disorder Severity can vary widely among individuals. Symptoms may range from mild to severe. In some cases, tics can significantly impair daily functioning, while in others, they are relatively minor and manageable.
Healthcare Professionals: Disease Ontology ID - DOID:11119
Pathophysiology: Tourette's Disorder, also known as Tourette Syndrome, is a neurological condition characterized by repetitive, involuntary movements and vocalizations called tics. The pathophysiology of Tourette’s Disorder is not fully understood, but it is believed to involve dysfunction in the cortico-basal ganglia-thalamo-cortical (CBGTC) circuits. These circuits are crucial for motor control, and their dysfunction may lead to the tic symptoms.

Additionally, abnormalities in neurotransmitter systems, particularly dopamine and serotonin, are thought to play a significant role. Genetic factors also contribute, as Tourette’s Disorder often runs in families, indicating a hereditary component. Environmental factors such as prenatal stress, infections, and other prenatal or perinatal issues may also influence the development and severity of the disorder.
Carrier Status: Tourette's Disorder is not typically described in terms of "carrier status," as it is a complex neuropsychiatric condition rather than a simple genetic disorder. It involves multiple genetic and environmental factors. Therefore, there is no single genetic marker or carrier status for Tourette's Disorder.
Mechanism: The exact mechanism affecting the inherited vulnerability to Tourette's is not well established. Tics are believed to result from dysfunction in cortical and subcortical brain regions: the thalamus, basal ganglia and frontal cortex. Neuroanatomic models suggest failures in circuits connecting the brain's cortex and subcortex; imaging techniques implicate the frontal cortex and basal ganglia. In the 2010s, neuroimaging and postmortem brain studies, as well as animal and genetic studies, made progress towards better understanding the neurobiological mechanisms leading to Tourette's. These studies support the basal ganglia model, in which neurons in the striatum are activated and inhibit outputs from the basal ganglia.Cortico-striato-thalamo-cortical (CSTC) circuits, or neural pathways, provide inputs to the basal ganglia from the cortex. These circuits connect the basal ganglia with other areas of the brain to transfer information that regulates planning and control of movements, behavior, decision-making, and learning. Behavior is regulated by cross-connections that "allow the integration of information" from these circuits. Involuntary movements may result from impairments in these CSTC circuits, including the sensorimotor, limbic, language and decision making pathways. Abnormalities in these circuits may be responsible for tics and premonitory urges.The caudate nuclei may be smaller in subjects with tics compared to those without tics, supporting the hypothesis of pathology in CSTC circuits in Tourette's. The ability to suppress tics depends on brain circuits that "regulate response inhibition and cognitive control of motor behavior". Children with TS are found to have a larger prefrontal cortex, which may be the result of an adaptation to help regulate tics. It is likely that tics decrease with age as the capacity of the frontal cortex increases. Cortico-basal ganglia (CBG) circuits may also be impaired, contributing to "sensory, limbic and executive" features. The release of dopamine in the basal ganglia is higher in people with Tourette's, implicating biochemical changes from "overactive and dysregulated dopaminergic transmissions".Histamine and the H3 receptor may play a role in the alterations of neural circuitry. A reduced level of histamine in the H3 receptor may result in an increase in other neurotransmitters, causing tics. Postmortem studies have also implicated "dysregulation of neuroinflammatory processes".
Treatment: Treatment for Tourette's Disorder typically involves a combination of therapies aimed at managing symptoms. These may include:

1. Medications: Often prescribed to help control tics or treat related conditions such as ADHD or OCD. Common medications include antipsychotics, alpha-2 adrenergic agonists, and other pharmacological agents.

2. Behavioral Therapy: Comprehensive Behavioral Intervention for Tics (CBIT) is a widely used therapy that focuses on reducing tic severity through behavioral techniques.

3. Psychotherapy: Counseling can help manage the social and emotional aspects of the disorder, including addressing anxiety and improving social skills.

There is no cure for Tourette's Disorder, but these treatments can help manage symptoms effectively.
Compassionate Use Treatment: For Tourette's Disorder, compassionate use treatment and off-label or experimental treatments are considered when standard therapies are ineffective. Below are some options:

1. **Deep Brain Stimulation (DBS):** DBS is an experimental surgical treatment where electrodes are implanted in specific brain areas. It has shown promise in reducing tics in severe cases.

2. **Cannabinoids:** Some studies suggest that medical marijuana or cannabinoid-based medications may help manage tics, though this use is still experimental.

3. **Vagus Nerve Stimulation (VNS):** VNS involves stimulating the vagus nerve with an electrical device, which is experimental and under study for Tourette's.

4. **Medications:**
- **Pimozide:** Traditionally used for schizophrenia, this antipsychotic has been used off-label for Tourette’s.
- **Topiramate:** Typically used for epilepsy, some studies have shown it may help reduce tics.
- **Aripiprazole:** An antipsychotic used off-label for tic reduction with some success.

5. **Behavioral Interventions:**
- **Comprehensive Behavioral Intervention for Tics (CBIT):** While not off-label in the traditional pharmacologic sense, it is an evidence-based behavioral therapy that can be part of an extensive treatment plan.

These treatments are typically considered on a case-by-case basis and should be managed by specialists familiar with Tourette's Disorder.
Lifestyle Recommendations: For managing Tourette's Disorder, the following lifestyle recommendations can be beneficial:

1. **Education and Awareness**: Understanding the condition and educating family, friends, and teachers can help create a supportive environment.
2. **Regular Exercise**: Engaging in physical activities can reduce stress and improve overall well-being.
3. **Healthy Diet**: Eating a balanced diet can support overall health and potentially mitigate stress-related tics.
4. **Relaxation Techniques**: Practices like yoga, meditation, and deep-breathing exercises can help manage stress and anxiety, which may reduce tic severity.
5. **Consistent Routine**: Maintaining a regular daily schedule can provide structure and reduce anxiety.
6. **Adequate Sleep**: Ensuring sufficient and quality sleep is crucial, as fatigue can exacerbate tics.
7. **Support Groups**: Joining support groups can provide emotional support and practical advice from others with similar experiences.
8. **Behavioral Therapy**: Techniques like Comprehensive Behavioral Intervention for Tics (CBIT) can help manage symptoms.

Consulting a healthcare professional for personalized recommendations is advisable.
Medication: Children with tics typically present when their tics are most severe, but because the condition waxes and wanes, medication is not started immediately or changed often. Tics may subside with education, reassurance and a supportive environment. When medication is used, the goal is not to eliminate symptoms. Instead, the lowest dose that manages symptoms without adverse effects is used, because adverse effects may be more disturbing than the symptoms being treated with medication.The classes of medication with proven efficacy in treating tics—typical and atypical neuroleptics—can have long-term and short-term adverse effects. Some antihypertensive agents are also used to treat tics; studies show variable efficacy but a lower side effect profile than the neuroleptics. The antihypertensives clonidine and guanfacine are typically tried first in children; they can also help with ADHD symptoms, but there is less evidence that they are effective for adults. The neuroleptics risperidone and aripiprazole are tried when antihypertensives are not effective, and are generally tried first for adults. Because of lower side effects, aripiprazole is preferred over other antipsychotics. The most effective medication for tics is haloperidol, but it has a higher risk of side effects. Methylphenidate can be used to treat ADHD that co-occurs with tics, and can be used in combination with clonidine. Selective serotonin reuptake inhibitors are used to manage anxiety and OCD.
Repurposable Drugs: The concept of repurposing drugs for Tourette's Disorder involves using medications originally developed for other conditions to manage symptoms of Tourette's. Some repurposable drugs that have shown potential include:

1. **Clonidine** and **Guanfacine**: Initially used for hypertension, these alpha-2 adrenergic agonists can help reduce tics and improve attention and impulsivity.

2. **Topiramate**: Originally an anticonvulsant medication, it has been found to help some patients with Tourette's reduce tic severity.

3. **Fluoxetine**: This selective serotonin reuptake inhibitor (SSRI) is primarily prescribed for depression and anxiety but may also help with some psychiatric symptoms of Tourette's.

4. **Risperidone** and **Aripiprazole**: Atypical antipsychotics primarily used for bipolar disorder and schizophrenia can be effective in managing tics.

These medications can offer alternative treatment options, but their use should be closely supervised by a healthcare provider to monitor for efficacy and potential side effects.
Metabolites: In Tourette's Disorder, research on metabolites focuses on understanding the biochemical changes that might contribute to the condition. Metabolites associated with Tourette's Disorder include alterations in neurotransmitters like dopamine, serotonin, and norepinephrine. Specific studies often investigate the metabolites of these neurotransmitters, such as homovanillic acid (a dopamine metabolite) and 5-hydroxyindoleacetic acid (a serotonin metabolite), to explore their roles in the condition's pathophysiology. Understanding these metabolites may help in developing targeted treatments.
Nutraceuticals: There is limited scientific evidence to support the effectiveness of nutraceuticals in treating Tourette's Disorder. While some individuals may explore options such as omega-3 fatty acids, magnesium, vitamin B6, and others, their impact on tic severity or frequency is not well-established and can vary significantly among individuals. Always consult a healthcare provider before starting any nutraceutical regimen.
Peptides: Tourette's Disorder involves motor and vocal tics. While peptides are short chains of amino acids involved in various bodily functions, there is currently no established treatment for Tourette's Disorder that specifically targets peptides. Research into peptides and their role in neurological disorders is ongoing, but no peptide-based therapies are standard in clinical practice for this condition.