A Guide to Huntington's Disease
This article will explain what Huntington’s disease is. It will also describe the symptoms, causes, and treatment options of the condition.
Huntington’s disease is a disorder that eventually causes the brain to stop working properly over time. According to the National Health Service (NHS), it is usually fatal after a period of 20 years.
The disease is mostly inherited in families. It is an altered gene that people pass to their biological children, so if you have this altered gene, you will eventually develop the condition.
Huntington’s disease causes broad effects on the brain. Problems can develop with movement, thinking, reasoning, and mood. The combination of symptoms in these areas overlaps with three other degenerative diseases, which are:
- Parkinson’s disease
- Alzheimer’s disease
- amyotrophic lateral sclerosis, also known as Lou Gherig’s disease
Treatment can not reverse or slow the progression of Huntington’s disease. Instead, Huntington’s disease treatment focuses on managing symptoms with medications.
Physical, occupational, and other types of therapy may also be part of a comprehensive treatment plan. This approach can help people overcome limits to their abilities for some time.
Who gets Huntington’s disease?
You are at risk of developing Huntington’s disease if one of your biological parents has it. If a person has the Huntington’s disease gene, there is a 50% chance that each of their biological children will have it. They, in turn, can also pass the gene to their biological children.
On rare occasions, it is possible to develop Huntington’s disease without a biological parent having it, but this is usually because the parent did not receive a diagnosis.
Huntington’s disease involves a slow decline in many bodily functions. Symptoms usually begin between the ages of 30 and 50 years but can begin as early as 2 years old. It affects cognitive ability, movement, and behavior.
Cognitive symptoms of Huntington’s disease
Common cognitive symptoms of Huntington’s disease include:
- difficulty concentrating, planning, or organizing
- forgetfulness or slowness in processing thoughts
- impaired judgment
- problems learning new information or making decisions
Movement symptoms of Huntington’s disease
Common movement symptoms of Huntington’s disease include:
- unusual eye movements
- rigid muscles and uncontrolled movements of the head, face, arms, legs, or upper body
- slurred speech and difficulty swallowing
- unsteady gait and problems with posture and balance
Psychiatric symptoms of Huntington’s disease
Common psychiatric symptoms of Huntington’s disease include:
- depression and other mood problems, such as anxiety, anger, and irritability
- obsessive-compulsive disorder and bipolar disorder
- personality changes
- social withdrawal, sleep problems, fatigue, and suicidal thoughts
It is possible for symptoms to occur in children and teenagers. This is juvenile-onset Huntington’s disease. The symptoms are somewhat different in this age group and will progress faster than in adults.
Common symptoms of juvenile-onset Huntington’s disease
Juvenile-onset Huntington’s disease occurs when symptoms are present before the age of 20 years.
Common symptoms of juvenile-onset Huntington’s disease include:
- loss of academic skills and declining cognitive function
- problems with school performance and behavior problems
- tremors, problems with fine motor skills, clumsiness, and gait changes
Various other conditions can also be responsible for the symptoms of Huntington’s disease. Seeing your doctor is the only way to know for sure what is causing them.
If Huntington’s disease runs in your family, talk with your doctor about genetic testing. Knowing whether or not you have the altered gene can help you plan your medical care.
A single defective gene causes Huntington’s disease. You can locate the gene on chromosome 4, which is one of the 23 human chromosomes.
Everyone has this gene. However, in Huntington’s disease, one section of the gene repeats itself too many times. Scientists call this an expanded sequence. In essence, the section is longer than it should be. This means the protein the gene is responsible for making also ends up being too long.
Scientists do not fully understand the function of this protein yet. However, they know that the expanded sequence makes the protein toxic to the brain’s nerve cells.
Usually, the only risk factor for developing Huntington’s disease is having a parent with the altered gene. The gene is dominant. This means if you inherit the gene, you will get the disease.
You inherit one copy of every gene, except sex genes, from each biological parent. The two copies can be the same, or they can be different. If both parents have two healthy copies of the gene, you will not get Huntington’s disease.
However, if one parent has an altered copy and a healthy copy, you have a 50% chance of inheriting the altered gene and developing the disease.
Reducing your risk of Huntington’s disease
Currently, there is no way of preventing Huntington’s disease. However, genetic testing can give you some control over your healthcare.
If you have a biological parent with Huntington’s disease, talk with your doctor about genetic testing. If you have the gene, you can make decisions about your future care before symptoms begin.
Depending on your symptoms, your doctor may recommend the following:
- antidepressants, such as selective serotonin reuptake inhibitors (SSRIs) for obsessive-compulsive thoughts and actions
- antipsychotics, which can help both psychiatric and movement problems
- antiseizure drugs, which can also act as mood stabilizers
- tetrabenazine, which has Food and Drug Administration (FDA) approval to treat Huntington’s chorea
Your doctor may need to make several adjustments as the disease progresses.
They may also recommend various forms of therapy to manage symptoms. This may include:
- physical and occupational therapy to help with movement
- speech and swallowing therapy
- cognitive behavioral therapy to help with psychiatric symptoms
Social service providers can also help create an optimal home, school, or work environment and provide access to support services.
Research is currently underway to find new ways of slowing down or stopping the progression of the disease, including ways to “switch off” the altered gene and use cultures to understand why neurons die.
If you have a biological parent or grandparent who had Huntington’s disease, you should arrange a genetic test to see if you will also get it. A doctor will take a blood sample to test for the genetic fault that causes the condition.
If you have symptoms, there are various tests doctors will undertake to determine if you have the disease, including:
- Neurological exam: A neurological exam will include testing your reflexes, balance, movement, mental ability, hearing, walking, and muscle tone.
- Diagnostic imaging: This involves brain imaging, such as a CT scan or an MRI scan. These scans may show shrinkage in the brain, though other conditions may also cause this.
Huntington’s disease is ultimately fatal. However, the rate of disease progression varies from person to person. In general, people with the disease survive anywhere from 10–25 years after diagnosis. The juvenile form of the disease tends to progress faster.
You should talk with your doctor about your own individual outlook for Huntington’s disease.
As the disease progresses, complications can include:
- losing the ability to care for yourself or communicate
- losing awareness of people and surroundings
- injuries related to falls
- an inability to swallow, also called dysphagia
- heart failure
A dedicated caregiver is essential for a person in the later stages of Huntington’s to live safely. Both the person with Huntington’s and the caregivers need a network of friends and family to lend support.
Because Huntington’s disease is fatal, people with the disease need to plan for end-of-life care. This includes choosing care facilities or hospice care for the later stages of the disease.
Here are some frequently asked questions about Huntington’s disease.
How common is Huntington’s disease?
Huntington’s is a rare disease. There are currently 41,000 people in the United States with symptoms and over 200,000 at risk of inheriting it from biological family members.
How do you test for Huntington’s disease?
Testing for Huntington’s disease involves taking a sample of blood to test for the genetic fault.
What is the average life expectancy for a person with Huntington’s disease?
It is usually fatal after around 20 years from the diagnosis.
Huntington’s disease is a neurodegenerative condition that can cause the gradual decline of cognitive, motor, and behavioral abilities.
It is a genetic condition that is inherited from a person’s biological parents, with symptoms usually starting at around age 30 years. Symptoms include involuntary jerking or other movements, personality changes, issues with swallowing and speaking, and memory lapses.
Seek prompt medical attention if you notice any changes in your motor or cognitive skills or if you experience any mental or emotional problems.