Huntington Disease (HD)

Huntington disease (HD) is a rare, hereditary, neurodegenerative disorder affecting the central nervous system, especially the caudate nucleus and putamen within the basal ganglia.¹ HD is characterized by a wide range of motor, cognitive, and psychiatric symptoms, most notably of which are uncontrollable, involuntary movements of the extremities and facial muscles (chorea).¹

Although there is no cure for HD at present, current treatments, including physical therapy, occupational therapy, speech therapy, psychotherapy, and specific pharmaceuticals, can help manage the symptoms of the condition.¹

Physical Therapy

Patients with HD may experience rigidity or extreme stiffness around the joints due to progressively increasing muscle tone. Dystonia may also co-occur with rigidity. Active and passive physical therapy exercises enable patients with HD to maintain joint range of motion, prevent contractures, and minimize the development of postural and musculoskeletal deformities.¹

Low-impact exercises and routine physical activity are encouraged. Physical therapists help to develop personalized exercise programs for people with HD to maintain or improve their functional mobility and independence.¹

Individuals with HD also develop gait and balance impairments, including disrupted ability to regulate cadence during ambulation, increased postural sway, increased variability in step length and width, and increased difficulty initiating movement. These impairments may lead to injuries due to falls, a decreased quality of life, and loss of independence.¹

Physical therapy can help decrease fall risk among patients with HD who have gait and balance disturbances. Targeted exercises that focus on core stabilization, normalization of gait, fall prevention, and balance strategies, as well as attention training, are recommended interventions for this patient population.¹

Read more about HD complications

Occupational Therapy

Both physical and occupational therapy aim to allow patients with HD to maintain their independence for as long as possible. A physical or occupational therapist can teach individuals with HD who have significant balance impairment to use assistive devices such as walkers to increase their base of support and stability to decrease the risk of falling.¹

Occupational and physical therapy can help minimize the impact of fine motor skill deterioration of functional capabilities. Use of adaptive aids may prove beneficial to overcome impaired manual dexterity.¹

Occupational therapists can also evaluate the severity of cognitive dysfunction and address home safety concerns. Use of unbreakable dinnerware, oven mitts, covered mugs for hot liquids, and timers as a reminder to turn off appliances may help mitigate injury. Commonly used items should be stored on lower shelves of cabinets instead of higher areas to prevent loss of balance and injury due to falls.²

Occupational therapists often recommend the removal of trip hazards, such as throw rugs or thick carpeting. Furniture in rooms can be stabilized, and unnecessary furniture can be removed. Tables and lamps should be moved away from walkways, and sharp edges of furniture and doorways can be padded to prevent injury. Shower chairs or benches, safety bars, nonslip bath mats, and soap on a rope can help prevent falls in the shower.²

Read more about HD care team

Speech Therapy

In the early stages of HD, individuals develop problems controlling the muscles of the mouth and throat involved in eating, chewing, and swallowing. Dysphagia may progress to become a major problem in later stages of the disorder, increasing the risk of choking, aspiration, aspiration-induced upper respiratory tract infections, and potential cardiac arrest.¹ 

In addition to swallowing disorders, HD may also affect the ability to speak and articulate thoughts clearly, making conversations difficult.³

Speech-language pathologists should be consulted early in the course of disease. Speech therapists may recommend eating more slowly, selecting softer foods, and eating around the same time every day. They may also suggest breathing exercises and oral-facial exercises to help with speech articulation.³ 

Oral-facial exercise accompanied by swallow sequence individualization and cough post swallow may improve swallowing difficulties. Caregiver instruction on swallowing regimes and management of eating and drinking is an important part of speech therapy.¹

As communication becomes more challenging, speech therapists may teach individuals with HD to use assistive devices, such as smart devices, notebooks, picture boards, or computers, to assist with communication.³ 

Regular monitoring and evaluation of swallowing disorders should be performed throughout the course of the disease. Some individuals with severe dysphagia may require percutaneous endoscopic gastrostomy (PEG) to maintain adequate nutrition and prevent choking, aspiration, and related complications.¹

Read more about HD prognosis

Psychotherapy

Cognitive and behavioral changes often precede motor dysfunction in individuals with HD. Psychotherapy and cognitive behavioral therapy can help detect and manage mood or psychiatric disorders that occur more frequently among persons with HD, such as depression, anxiety, apathy, irritability, suicidal ideation, impulsivity, obsessions, and hallucinations.¹ Psychotherapists can recommend pharmaceutical therapies to help manage certain psychiatric or behavioral symptoms.¹ 

True obsessive-compulsive disorders are sensitive to cognitive behavioral therapy and psychological interventions when cognition is not impaired.¹ Electroconvulsive therapy may be recommended under the guidance of a psychiatrist in cases of severe depression that are refractory to oral medications.¹

Most research on psychological therapy for HD has centered around anxiety, depression, apathy, irritability, and coping strategies; however, more comprehensive, high-quality research is still required to aid in the determination of the most effective and beneficial treatments for this patient population.⁴

Read more about HD guidelines

Pharmaceutical Therapies

Although motor symptoms form the basis of a manifest HD diagnosis, these symptoms are sometimes well-tolerated, in contrast with cognitive and behavioral symptoms, which may have caused long-standing family and social issues. However, all pharmaceutical treatment for symptom management should be carefully considered, not only for patient benefit, but weighed against possible side effects. Many symptoms of HD, such as rigidity, bruxism, memory loss, or depression, can be induced or exacerbated by the same therapies used to control other symptoms.¹ 

Xenazine^® (tetrabenazine) and Austedo^® (deutetrabenazine) are first-line treatments for chorea in the absence of uncontrolled depression or suicidal ideation. Pharmaceutical management of chorea can also help manage a patient’s walking, balance, and dexterity. Benzodiazepines, such as Klonopin^® (clonazepam), can help reduce myoclonus; however, it is important to monitor for side effects that may increase the risk of falling due to somnolence.¹

For patients with HD who demonstrate behavioral or psychotic disorders, second-generation, or atypical, neuroleptics are the first-line treatments for chorea.¹ Neuroleptics can also help manage aggressive behaviors and hallucinations. Atypical neuroleptics combined with serotonergic antidepressants may reduce perseverative ideations.¹

Antidepressants, such as selective serotonin reuptake inhibitors (SSRIs), and mood stabilizers may reduce irritability, depression, depression-related apathy, anxiety, impulsivity, and obsessions.¹ 

Read more about HD therapies

References 

1. Bachoud-Lévi AC, Ferreira J, Massart R, et al. International guidelines for the treatment of Huntington’s disease. Front Neurol. 2019;10:710. doi:10.3389/fneur.2019.00710
2. Physical and occupational therapy – Huntington’s disease: family guide series. Huntington’s Disease Society of America. Accessed August 5, 2023. 
3. Speech therapy for Huntington’s disease. Huntington’s Disease News. Accessed August 5, 2023.
4. Zarotti N, Dale M, Eccles F, Simpson J. Psychological interventions for people with Huntington’s disease: a call to arms. J Huntingtons Dis. 2020;9(3):231-243. doi:10.3233/JHD-200418

Reviewed by Hasan Avcu, MD, on 8/9/2023.

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Maria Arini Lopez, PT, DPT, CSCS, CMTPT, CIMT

Maria Arini Lopez, PT, DPT, CSCS, CMTPT, CIMT is a freelance medical writer and Doctor of Physical Therapy from Maryland. She has expertise in the therapeutic areas of orthopedics, neurology, chronic pain, gastrointestinal dysfunctions, and rare diseases especially Ehlers Danlos Syndrome.