Huntington’s disease (HD) is named for George Huntington, the doctor who first described it in the late 1800s. It’s a rare, progressive, genetic disorder that causes uncontrollable movements, cognitive impairment, and psychiatric symptoms. If you’ve been diagnosed with the disease, which has no cure, you might feel completely helpless. But there is hope. Treatments exist to control the symptoms, and they can help extend your life.
At Memphis Neurology, with locations in Germantown, Tennessee, and Southaven, Mississippi, our expert team of neurologists has extensive experience treating Huntington’s disease and other movement disorders. They want you to know that there’s life after diagnosis and what living with the disease entails. They’ve put together this guide to help you understand what the future holds for you.
Huntington’s disease 101
HD is caused by a single defective gene on chromosome 4 (one of the 23 chromosomes that carry a person’s genetic code), which leads to the progressive degeneration of nerve cells in the brain. The degeneration affects central brain areas that control movement; thinking skills; and depression, irritability, and other mood changes.
The defective gene contains the code for a protein called huntingtin, whose normal function isn’t known at this time. It was identified in 1993, and it’s responsible for almost all cases of HD.
The huntingtin defect involves extra repeats of a single chemical code in one small section of the chromosome. While the normal version of huntingtin contains 17 to 20 repetitions of this code among more than 3,100 codes of the gene, the HD defect includes 40 or more repeats. Genetic tests for Huntington's disease look at the number of repeats in the sequence of a person's huntingtin gene.
The genetic defect is "dominant," which means that anyone who inherits it from a parent who has Huntington's will eventually develop the disease.
Symptoms of HD
HD symptoms usually first appear in people in their 30s or 40s. If it develops before age 20, it's called juvenile Huntington's disease. Individuals with the adult-onset form usually live about 15-20 years after symptoms begin. There are three categories of symptoms:
These encompass both involuntary movement problems and impairments of involuntary movements, including:
- Involuntary jerking or writhing (chorea)
- Muscle rigidity or contracture (dystonia)
- Slow or abnormal eye movements
- Problems with gait, posture, and balance
- Difficulty with speech and swallowing
These encompass mental health conditions. Impairments include:
- Difficulty focusing on, prioritizing, or organizing tasks
- The tendency to get stuck on a thought, behavior, or action
- Lack of impulse control, resulting in outbursts and acting without thinking
- Sexual promiscuity
- Difficulty processing thoughts or ''finding'' words
- Difficulty learning new information
The most common psychiatric disorder is depression, not just related to the diagnosis, but more from injury to the brain and subsequent changes in brain function. Other symptoms include:
- Irritability, sadness, or apathy
- Social withdrawal
- Fatigue and loss of energy
- Obsessive-compulsive disorder
- Bipolar disorder or mania
- Frequent thoughts of death and suicide
Diagnosis of and treatments for HD
Doctors make a diagnosis of HD based on a neurological examination, neuropsychological testing, a psychiatric evaluation, brain imaging and functional testing, and genetic testing and counseling.
At this time, no treatments can change the outcome of HD, but medications can lessen some symptoms of movement and psychiatric disorders.
Drugs to control movement include the FDA-approved tetrabenazine (Xenazine) and deutetrabenazine (Austedo), which suppress the involuntary jerking and writhing movements (chorea), antipsychotic drugs, and a few other medications.
Medications to treat psychiatric disorders vary depending on the disorders and symptoms but may include:
- Antidepressants; may also have some effect on treating obsessive-compulsive disorder
- Antipsychotic drugs; side effects may cause different movement disorders themselves
- Mood-stabilizing drugs; include anticonvulsants used for bipolar disorder, such as divalproex (Depakote), carbamazepine (Carbatrol), and lamotrigine (Lamictal).
And other interventions can help a person adapt to changes in lifestyle and abilities for a certain amount of time, such as:
- Speech therapy
- Physical therapy
- Occupational therapy
If you have a family history of Huntington’s disease, or if you’ve been recently diagnosed, it’s important to understand what the course of the rest of your life will be like. Here at Memphis Neurology, we can help you through every step of the way. Give us a call at either of our locations or set up a consultation online today.