Huntington’s disease is genetic and has no cure.
What is Huntington’s Disease?
In Huntington’s disease, a genetic disorder, nerve cells in the brain degenerate. This impacts thinking, movement, and mood. Symptoms develop in patients around their 30s and 40s, but for those who develop symptoms earlier than age 20, the disorder is called “juvenile Huntington’s disease”. The movement disorder symptoms include rigidity (dystonia) in the muscles, chorea (jerking or writhing), abnormal eye motions, impaired balance, gait, and posture, and trouble with swallowing and speech. Cognitive symptoms include trouble organizing tasks, difficulty focusing, perseveration (getting stuck on thoughts), impulse control problems, not having awareness of one’s behaviors, and trouble with learning new information and finding words. Depression is common with HD. Patients may also have psychiatric symptoms such as insomnia, fatigue, thoughts of suicide, social withdrawal, apathy, sadness, or irritability. It is not uncommon for patients with HD to have mania, bipolar disorder, or obsessive-compulsive disorder. Another physical sign of Huntington’s disease is weight loss. Patients will have behavioral changes, and they might also have tremors or seizures. HD is caused by a single inherited gene defect. Only one copy of this gene is needed for Huntington’s disease to develop; therefore children have a 50% chance of receiving this gene and developing HD if they have a parent with the disease. Death results within 10 years of juvenile HD and 10-30 years for adult-onset HD. The risk of suicide is high. Patients with Huntington’s disease will ultimately need help with daily care and living; as the disease progresses, they will be unable to speak and will likely be bedridden. Aside from suicide, HD can cause death via pneumonia, infections, injuries from falls, or the inability to swallow leading to complications.1
Diagnosis and Treatments
Patients can undergo genetic counseling either before the symptoms or after. There are many ethical issues regarding genetic testing including the appropriate age to receive the diagnosis, whether parents have the right to test children, and the disclosure and confidentiality of the results. There is no cure, but some medications have been developed to relieve symptoms. Clinical trials and research are focused on treating symptoms, slowing the progression, or looking into stem cell therapy to repair damage from HD.2 People who have HD in their family history, but who don’t yet have symptoms, have a 50% chance of developing the disease. Some may choose to undergo “presymptomatic testing”, but others may not. A positive diagnosis might impact future career choices, marriage options, and family planning. On the other hand, not getting tested can lead to misdiagnosis. Alcoholism and mood disorders may be diagnosed instead, for example. Neurologists can test for early symptoms as well, by checking eye motion, hearing, coordination, strength, balance, reflexes, and mental and emotional states. Tetrabenazine treats the chorea. Antipsychotic drugs may also be prescribed for the hallucinations and violent outbursts, but they worsen dystonia. Antidepressants, anti-anxiety medications, and lithium are other treatments options. All of the medications have side effects. Patients who exercise fare better than inactive ones. Walking is important, with “sturdy shoes”, and it should be continued, even with assistance, if balance problems develop. Caregivers need to make sure patients receive enough calories as HD patients may “burn as many as 5,000 calories a day without gaining weight”.3 The Huntington’s Disease Society of America (HDSA) is a non-profit organization that promotes research and education on HD. They can connect patients and their families with support groups as well.4