The range of disease duration was between 2 and 17 years, the oldest living to age 91.
Frequency. Huntington disease affects an estimated 3 to 7 per 100,000 people of European ancestry. The disorder appears to be less common in some other populations, including people of Japanese, Chinese, and African descent.
While the cause of the disease is known — a single mutated gene — there is no cure. “Our plan is to conduct human clinical trials that deliver stem cells to replace damaged brain cells, reducing levels of harmful proteins that build up in the brains of Huntington's disease patients.”
You're usually only at risk of developing it if one of your parents has or had it. Both men and women can get it. If a parent has the Huntington's disease gene, there's a: 1 in 2 (50%) chance of each of their children developing the condition – affected children are also able to pass the gene to any children they have.
Onset occurring ≤20 years is classified arbitrarily as juvenile-onset HD (JHD). The youngest symptomatic child documented had an age of onset of 18 months,3 with other children developing symptoms in their teens, meaning that some individuals with JHD may now be in their twenties.
It affects males and females equally and crosses all ethnic and racial boundaries. Typically, symptoms begin between age 30 and 55. Children of parents with Huntington's disease have a 50 percent chance of inheriting the HD gene.
After Huntington's disease starts, a person's functional abilities gradually worsen over time. The rate of disease progression and duration varies. The time from the first symptoms to death is often about 10 to 30 years. Juvenile Huntington's disease usually results in death within 10 years after symptoms develop.
This disease often affects a person's ability to plan, make decisions, and process complex topics. But patients usually retain past memories, and are able to recognize people, objects, letters, numbers, and colors. They are often able to continue carrying out jobs that they have previously been doing for many years.
No treatments can alter the course of Huntington's disease. But medications can lessen some symptoms of movement and psychiatric disorders. And multiple interventions can help a person adapt to changes in abilities for a certain amount of time.
The disease gets worse over time. Early signs of HD can vary, but often include mild clumsiness or problems with balance or movement, cognitive or psychiatric symptoms (problems with thinking or emotion), and changes in behavior.
People can start to show the symptoms of Huntington's disease at almost any age. Most will develop problems between the ages of 30 and 50. The condition gradually gets worse for around 10-25 years, until the person dies.
The most painful conditions in Huntington's, said Achterberg, are limb pain, headache, abdominal pain and fractures. “I think we should do more work in validation of pain tools, including observational pain instruments,” he said. “And for clinicians, I suggest you be especially aware of abdominal pain.”
They may lack inhibition, and do or say things that one would normally find embarrassing. People with Huntington's may also be less able to control their emotions, possibly leading to outbursts of screaming, swearing, slamming doors, hitting walls, or the like. Patterns of behavior can change as the disease progresses.
Pneumonia and heart disease are the two leading causes of death for people with HD.
There have been reports that juvenile onset Huntington's chorea is almost always inherited from the father, and that late-onset Huntington's chorea is inherited more often from the mother than from the father.
Weight loss can make symptoms worse and weaken the patient's immune system, making them more vulnerable to infections and other complications. Huntington's disease itself is not usually fatal, but it can lead to choking, pneumonia, or other infections that can lead to death.
Aerobic exercise has been shown to improve cardiovascular fitness and motor function in people with Huntington's. Aerobic exercise requires continuous movement of large muscles to increase the heart rate. This can include activities such as stationary cycling, walking at a brisk pace or uphill, and swimming.
Many people with Huntington's disease report that their sleep patterns are affected and sometimes are awake most of the night, then continually catnap or doze throughout the day. Many find themselves experiencing long periods being awake or asleep.
during the time surrounding death. For the purpose of this fact sheet, the beginning of end-of-life in HD is determined as the stage when the person affected has little control over movement, is bedbound, unable to communicate, unable to eat and drink on his/her own and experiences severe chorea or extreme rigidity.
“Some people in this range do get Huntington's while some live into their 90s and never get a symptom,” says Shealy. “That's one of the limitations of genetic testing. We can't always give you a yes or no answer.”
Lots of people at risk of Huntington's disease decide they'd rather not know until any symptoms appear. If you do want to know, ask your GP for a referral to a genetic counsellor. You'll have several appointments with the counsellor.
Populations with a high prevalence of HD (i.e., Europeans and those of European ancestry) have a relatively high number of B7 alleles, which are associated with a high number of CAG repeats. This finding suggests that in these populations, new HD mutations may be more frequent, thus making HD more prevalent.