Huntington disease how many people are affected

The course of Huntington's is characterized by jerking uncontrollable movement of the limbs, trunk, and face chorea ; progressive loss of mental abilities; and the development of psychiatric problems. Huntington's disease progresses without remission over 10 to 25 years and patients ultimately are unable to care for themselves. Huntington's disease usually appears in middle age years , but can develop in younger and older people.

Juvenile HD also called Westphal variant or akinetic-rigid HD develops before the age of 20, progresses rapidly, and produces muscle rigidity in which the patient moves little, if at all akinesia. Huntington disease HD is a progressive disorder that causes motor, cognitive, and psychiatric signs and symptoms. On average, most people begin developing features of HD between ages 35 and Signs and symptoms vary by stage and may include: [1] [2] Early stage: Behavioral disturbances Clumsiness Moodiness Irritability Paranoia Apathy Anxiety Hallucinations Abnormal eye movements Depression Impaired ability to detect odors Middle stage: Dystonia Involuntary movements Trouble with balance and walking Chorea with twisting and writhing motions Unsteady gait style of walking Slow reaction time General weakness Weight loss Speech difficulties Stubbornness Late stage: Rigidity continual tension of the muscles Bradykinesia difficulty initiating and continuing movements Severe chorea Serious weight loss Inability to speak Inability to walk Swallowing problems Inability to care for oneself There is also a less common, early-onset form of HD which begins in childhood or adolescence.

Huntington disease HD is progressive, eventually leading to disability and death usually from a coexisting illness or infection. However, the disease affects everyone differently; the age of onset, specific symptoms, and rate of progression varies for each person with HD. While the symptoms of HD are well-characterized, their progression especially in the early and middle stages remains unpredictable.

With the approach of late-stage HD, affected people have speech difficulty and weight loss. In the late stage, affected people lose bowel and bladder control. Most people with HD survive for years after the onset of symptoms. The average age at death ranges from years, but the range may be broader. In a large study, pneumonia and cardiovascular heart disease were the most common primary causes of death.

However, there is still a lot of variability. Both genetic and environmental factors are thought to play a role on the age of onset in people with a mutation. Inheritance through the father can lead to more repeat expansion and earlier onset through succeeding generations, a phenomenon called anticipation. Huntington disease HD is inherited in an autosomal dominant manner.

Most people with HD have an affected parent. The family history can sometimes appear negative for various reasons even though a parent carries, or carried, a mutation in the HTT gene. In rare cases, HD is caused by a new de novo mutation in the HTT gene, in which case the disease occurs for the first time in the affected person and is not inherited from a parent.

A longer repeat in the HTT gene may cause earlier onset of symptoms. This phenomenon is called anticipation. Huntington disease HD does not occur in one generation, skip the next, and then reoccur in a subsequent generation.

However, HD may appear to skip a generation for one of the following reasons: Failure to recognize the disease in family members Early death of a parent before the onset of symptoms The presence of an intermediate allele an allele with CAG repeats or an HTT allele with reduced penetrance with CAG repeats , which may or may not result in HD in an asymptomatic parent Late onset of the disease in an affected parent [1] All people who inherit an allele with more than 40 CAG repeats will develop HD.

Is genetic testing available for Huntington disease? Why might an at-risk asymptomatic adult seek testing for Huntington disease? How might Huntington disease be treated?

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COVID is an emerging, rapidly evolving situation. Menu Search Home Diseases Huntington disease. Back to List of Questions. Question Question. I have a family history of Huntington's disease. My mother was diagnosed with it about 5 years ago. I just needed to know some information about where I can get tested.

Also, how early can they start treatment if I am diagnosed with it? I'm only 21 years old. I just thought that maybe the sooner they start the better. Answer Answer. The following information may help to address your question: What is Huntington disease? Huntington disease HD is an inherited condition that causes progressive degeneration of neurons in the brain.

Signs and symptoms usually develop between ages 35 to 44 years and may include uncontrolled movements, loss of intellectual abilities, and various emotional and psychiatric problems. People with HD usually live for about 15 to 20 years after the condition begins.