What is Huntington’s Disease?
Huntington’s disease is a neurodegenerative disease that is a genetic, progressive neurological disorder that slowly takes away a persons ability to walk, talk, and reason. It is characterized by the initial subtle symptoms of change in personality and motor skills ability. As the condition progresses, patients develop involuntary movements known as chorea (hence Huntington’s Chorea.) The word chorea comes from the Greek word choreia, which means “to dance”, which describes the uncoordinated, jerky body movements associated with the condition. Other motor symptoms eventually appear and may include difficulty speaking, walking or writing. It was reported in detail in 1872 by the American physician, George Huntington (1850-1916).
Symptoms of Huntington’s disease usually appear between the ages of 35-44 years old. Affected individuals can show a general lack of coordination and an unsteady gait. Other symptoms include depression, mood swings, forgetfulness, clumsiness, and involuntary twitching. As the disease progresses, concentration and short-term memory decrease and involuntary movements of the head, trunk and limbs increase. Huntington’s dementia eventually occurs. Patients will have memory loss associated with difficulty in abstract thinking, planning and avoiding inappropriate behavior.
In 1993, scientists discovered the gene that causes Huntington’s disease. HD is a genetic mutation stemming from the formation a chain of abnormal DNA sequences. There are four building blocks of DNA. Repeating DNA chains of cytosine-adenine-guanine (CAG) code for the protein glutamine, an amino acid. As a result, these long glutamine chain proteins clump together and are toxic to brain cells (neurons.) The more CAG repeat sequences there are, the more severe the symptoms of HD. Scientists have also discovered the more severely the gene is mutated, the earlier the onset of the disease.
There is no known cure for Huntington’s disease at this time . There are, however, treatments which can be employed to reduce the severity of some symptoms. Tetrabenazine was developed specifically to reduce the severity of chorea in HD. Other drugs that help to reduce chorea include Haldol, Risperdal and other neuroleptic medications. Valium like drugs known as benzodiazepines may also be helpful. Rigidity can be treated with antiparkinsonian drugs, and myoclonic hyperkinesia can be treated with valproic acid. Depression is common in HD and can be managed with medications in the serotonin reuptake inhibitor family, such as Prozac or citolopram.
Huntington’s Disease profoundly affects not only the patient, but the entire family — physically, emotionally, socially and economically. Since there is no known cure and the prognosis is poor, a plan of action should be developed jointly with a qualified neurologist who specializes in movement disorders so that the patient’s quality of life can be maintained as long as possible. Your neurologist can also help you locate and connect to some of the many support groups, organizations, and resources available to help with both the patient and the family and caregiver(s).
Innovative research is underway and aims to find better treatment options and ultimately hope and a cure for this debilitating condition. If you suspect that you or someone you love may be suffering from Huntington’s Chorea, contact Sarasota Neurology for an appointment.