From the Guidelines
Huntington's disease is a progressive genetic disorder that requires prompt diagnosis and management to improve quality of life, and genetic testing is the most effective way to confirm the diagnosis, as stated in the 2020 study by the Journal of the American College of Radiology 1.
Diagnosis and Management
The disease is caused by an inherited mutation in the HTT gene that creates an abnormal huntingtin protein, leading to movement, cognitive, and psychiatric symptoms. Common symptoms include involuntary jerking movements (chorea), impaired coordination, cognitive decline, depression, irritability, and personality changes.
- The disease typically appears in mid-adulthood (30s-40s) and worsens over 10-30 years.
- Currently, there is no cure for Huntington's disease, but medications can help manage symptoms.
- Tetrabenazine (Xenazine) or deutetrabenazine (Austedo) may reduce chorea, while antipsychotics like haloperidol or risperidone can help with movements and psychiatric symptoms.
- Antidepressants, mood stabilizers, and anti-anxiety medications are often prescribed for psychiatric manifestations.
- Physical, occupational, and speech therapy are important components of treatment.
Genetic Testing
Genetic testing is available for those with a family history, though this decision carries significant psychological implications.
- The disease is inherited in an autosomal dominant pattern, meaning children of affected individuals have a 50% chance of inheriting the mutation.
- The American College of Medical Genetics and Genomics recommends that genetic testing for Huntington's disease should include the CAG-repeat number in test reports, as well as an explanation of the significance of these allele sizes to the patient 1.
- A 2014 study by the American College of Medical Genetics and Genomics also emphasizes the importance of genetic testing and counseling for individuals with a family history of Huntington's disease 1.
Treatment Approach
A comprehensive treatment approach that includes medication, therapy, and genetic counseling is essential to improve the quality of life for individuals with Huntington's disease, as supported by the 2020 study by the Journal of the American College of Radiology 1.
From the Research
Huntington's Disease Overview
- Huntington's disease (HD) is a dominantly inherited progressive neurological disease characterized by chorea, an involuntary brief movement that tends to flow between body regions 2, 3.
- HD is typically diagnosed based on clinical findings in the setting of a family history and may be confirmed with genetic testing 2, 3, 4.
- Multiple areas of the brain degenerate, mainly involving the neurotransmitters dopamine, glutamate, and γ-aminobutyric acid 2, 3.
Treatment Options
- Tetrabenazine is a dopamine-depleting agent that may be one of the more effective agents for reducing chorea, although it has a risk of potentially serious adverse effects 5, 2, 6, 3.
- Some newer antipsychotic agents, such as olanzapine and aripiprazole, may have adequate efficacy with a more favorable adverse-effect profile than older antipsychotic agents for treating chorea and psychosis 2, 3.
- Current treatments are symptomatic, and largely directed at the chorea and neurobehavioural problems, although supporting trial evidence for these is often limited 6, 4.
Management and Diagnosis
- Patients are best managed in specialist multidisciplinary clinics, including when considering genetic testing 4.
- The diagnosis is usually confirmed through identification of an increased CAG repeat length in the huntingtin gene in a patient with clinical features of the condition 4.
- A growing number of conditions can mimic HD, including rare genetic causes, which must be considered in the event of a negative HD genetic test 4.