AMA News Wire<\/p>\n
What doctors wish patients knew about Huntington’s disease<\/p>\n
Aug 1, 2025<\/p>\n
Huntington’s disease, a rare but devastating genetic disorder, affects thousands of families each year, gradually robbing people of their movement, cognitive function and emotional stability. Often described as having amyotrophic lateral sclerosis<\/a>, Parkinson\u2019s disease<\/a> and Alzheimer\u2019s disease<\/a> simultaneously, this progressive illness carries a heavy emotional and physical toll, with symptoms typically emerging in adulthood. Knowing what to expect and how to prepare is key.<\/p>\n The AMA\u2019s\u00a0What Doctors Wish Patients Knew<\/a>\u2122 series gives physicians a platform to share what they want patients to understand about today\u2019s health care headlines.<\/p>\n In this installment, Lisa Toran, MD<\/a>, a neurologist who specializes in epilepsy at Confluence Health in Wenatchee, Washington, took time to discuss what patients need to know about Huntington\u2019s disease.\u00a0<\/p>\n Confluence Health<\/a> is part of the\u00a0AMA Health System Member Program<\/a>, which provides enterprise solutions to equip leadership, physicians and care teams with resources to help drive the future of medicine.<\/p>\n It\u2019s a rare genetic disorder<\/p>\n It\u2019s a rare genetic disorder<\/p>\n \u201cHuntington\u2019s disease<\/a> is a genetic neurodegenerative disorder that causes progressive involuntary abnormal movements, dementia and psychiatric symptoms,\u201d said Dr. Toran, noting that about 41,000 Americans today are symptomatic and more than 200,000 are at risk of inheriting the disease. \u201cThe most common type of this disease is adult-onset Huntington\u2019s disease, with symptoms usually starting in a person\u2019s 30s or 40s.\u201d<\/p>\n One symptom experienced in adult-onset Huntington\u2019s disease is chorea, which causes involuntary, irregular or unpredictable muscle movements in the arms, legs and facial muscles, she explained, adding that it also includes \u201ccognitive decline and psychiatric symptoms.\u201d<\/p>\n \u201cThe other less common type is juvenile Huntington\u2019s disease, which begins in childhood or adolescence, with symptoms including rigidity, bradykinesia, cognitive decline and often seizures,\u201d said Dr. Toran. \u201cIt progresses more rapidly than adult-onset Huntington\u2019s disease.\u201d<\/p>\n Additionally, \u201cHuntington\u2019s disease is relatively rare,\u201d she said. \u201cThe prevalence of Huntington\u2019s disease globally is approximately three to seven per 100,000 people and does occur more commonly in people of European ancestry.\u201d\u00a0<\/p>\n Huntington\u2019s disease is hereditary<\/p>\n Huntington\u2019s disease is hereditary<\/p>\n \u201cHuntington\u2019s disease is inherited from one parent to a child,\u201d said Dr. Toran. \u201cIt has an autosomal dominant pattern of inheritance, so only one copy of the altered gene in each cell will cause Huntington\u2019s disease.\u201d\u00a0<\/p>\n \u201cIndividuals with a family history of Huntington\u2019s are at risk of developing the disease,\u201d she said. \u201cThe autosomal dominant pattern of inheritance means that each child of a parent who has Huntington\u2019s disease has a 50% chance of inheriting the disease.\u201d<\/p>\n The cause is a repeat gene<\/p>\n The cause is a repeat gene<\/p>\n Huntington\u2019s disease \u201cis caused by an expanded CAG\u2014cytosine, adenine and guanine\u2014trinucleotide repeat in the huntingtin gene on chromosome 4, which leads to the production of a mutation huntingtin protein,\u201d Dr. Toran said. \u201cThis abnormal protein causes progressive breakdown or degeneration in some areas of the brain.\u201d<\/p>\n \u201cThe number of CAG repeats correlates with the onset and severity of the disease, with larger expansions usually leading to earlier onset and more severe symptoms,\u201d she said.<\/p>\n Genetic testing is key<\/p>\n Genetic testing is key<\/p>\n \u201cHuntington’s disease is diagnosed through a combination of clinical evaluation, family history and genetic testing,\u201d said Dr. Toran. \u201cIn the clinical evaluation, a physician will evaluate for typical symptoms such as chorea, cognitive decline and psychiatric disturbances.\u202f<\/p>\n \u201cMost patients will present with a family history of Huntington\u2019s disease,\u201d she added. But \u201cthe definitive diagnosis of Huntington\u2019s disease is made by genetic testing to identify an expansion of 36 or more CAG trinucleotide repeats in the huntingtin gene on chromosome 4.\u201d<\/p>\n \u201cWith genetic testing you can find out if you have Huntington\u2019s disease before clinical symptoms appear,\u201d Dr. Toran said. \u201cIf there are more than 40 CAG repeats in the huntingtin gene then it is predictable that the individual will go on to have symptoms of Huntington\u2019s disease.\u201d\u00a0<\/p>\n \u201cIt is important to personally consider if one wants to know this information ahead of time before genetic testing is sent,\u201d she said, noting that \u201cit can be helpful for personal decisions regarding reproduction, financial matters and career planning.\u201d<\/p>\n Dr. Toran added that \u201cif you have Huntington\u2019s disease and are planning to have children, then your risk of having a child with Huntington\u2019s disease is 50% for each child.\u201d She noted that \u201cit is possible to do in vitro fertilization with genetic testing to make sure you don\u2019t pass Huntington\u2019s disease down to your future children.\u00a0<\/p>\n \u201cAlternatively, if a child is naturally conceived, prenatal diagnosis \u2026 is possible,\u201d Dr. Toran added. \u201cA procedure, either chorionic villus sampling, performed at 10\u201313 weeks pregnant, or amniocentesis\u2014performed at 15\u201320 weeks pregnant\u2014can determine if the baby has inherited Huntington\u2019s disease.\u201d\u00a0<\/p>\n Symptoms fall into three categories<\/p>\n Symptoms fall into three categories<\/p>\n \u201cFirst there are motor symptoms, which can involve chorea, or involuntary jerking movements, dystonia\u2014sustained muscle contractions causing twisting or repetitive movements or abnormal postures\u2014bradykinesia or slowness, rigidity, slurred speech and difficulty with eye movements,\u201d said Dr. Toran.\u00a0<\/p>\n \u201cThere are also cognitive symptoms, such as impaired memory, planning, judgment and decision making,\u201d she said. \u201cAnd lastly there are psychiatric symptoms, which include depression<\/a>, personality changes and psychosis.\u201d\u00a0<\/p>\n \u201cThe first symptoms that appear in Huntington\u2019s disease are usually subtle changes in mood, coordination and cognition, such as clumsiness, mild depression, irritability and difficulty concentrating,\u201d Dr. Toran noted.<\/p>\n Chorea worsens as disease progresses<\/p>\n Chorea worsens as disease progresses<\/p>\n With Huntington\u2019s disease, chorea \u201cinvolves abnormal involuntary movements that are nonrepetitive and arrhythmic,\u201d said Dr. Toran, \u201cand can affect the entire body or just parts of the body such as the limbs, face or trunk.\u201d<\/p>\n \u201cTypically, these movements can start off mild and worsen as the disease progresses,\u201d she said. \u201cThese movements are typically present continuously while awake and can be exacerbated by stress.\u201d<\/p>\n Complications develop later<\/p>\n Complications develop later<\/p>\n \u201cDifficulty swallowing and speaking are common in later stages, leading to nutritional deficiencies and aspiration pneumonia,\u201d said Dr. Toran. \u201cPneumonia<\/a>, due to aspiration, is a leading cause of death in this disease.\u201d\u00a0<\/p>\n Additionally, with Huntington\u2019s disease, \u201cweight loss is common,\u201d she said. Meanwhile, \u201cthere is an increased risk of falls and injury from falls, such as bone fractures.\u201d\u00a0<\/p>\n Then, \u201cas the disease becomes more advanced, patients develop cognitive decline and then dementia,\u201d Dr. Toran said.<\/p>\n There is no cure\u00a0<\/p>\n There is no cure\u00a0<\/p>\n While \u201cthere is no cure for Huntington\u2019s disease, there are a few medications that can help improve symptoms,\u201d said Dr. Toran. \u201cFor example, tetrabenazine is recommended as a first-line pharmacologic treatment for Huntington\u2019s disease chorea.\u201d<\/p>\n Also, \u201cit is important to monitor and treat psychiatric disturbances such as depression, psychosis and aggression, which are commonly managed with psychotropic drugs such as antidepressants, antipsychotics and mood stabilizers,\u201d she said. \u201cWithout a cure, supportive care is essential, with a focus on optimizing the patient’s quality of life.\u202f<\/p>\n