Huntington's disease is an inherited disease that causes the progressive breakdown of nerve cells in the brain. Huntington's disease has a broad impact on a person's functional abilities and usually results in movement, thinking and psychiatric disorders.
Most people with Huntington's disease develop signs and symptoms in their 40s or 50s, but the onset of disease may be earlier or later in life. When disease onset begins before age 20, the condition is called juvenile Huntington's disease. Earlier onset often results in a somewhat different presentation of symptoms and faster disease progression.
Medications are available to help manage the symptoms of Huntington's disease, but treatments can't prevent the physical, mental and behavioral decline associated with the condition.
Symptoms of Huntington’s Disease
Huntington's disease usually causes movement, cognitive and psychiatric disorders with a wide spectrum of signs and symptoms. Which symptoms appear first varies greatly among affected people. During the course of the disease, some disorders appear to be more dominant or have a greater effect on functional ability.
Movement Disorders Associated with Huntington’s Disease
The movement disorders associated with Huntington's disease can include both involuntary movements and impairments in voluntary movements:
- Involuntary jerking or writhing movements (chorea)
- Involuntary, sustained contracture of muscles (dystonia)
- Muscle rigidity
- Slow, uncoordinated fine movements
- Slow or abnormal eye movements
- Impaired gait, posture and balance
- Difficulty with the physical production of speech
- Difficulty swallowing
Impairments in voluntary movements — rather than the involuntary movements — may have a greater impact on a person's ability to work, perform daily activities, communicate and remain independent.
Cognitive Disorders Associated with Huntington’s Disease
Cognitive impairments often associated with Huntington's disease include:
- Difficulty planning, organizing and prioritizing tasks
- Inability to start a task or conversation
- Lack of flexibility, or the tendency to get stuck on a thought, behavior or action (perseveration)
- Lack of impulse control that can result in outbursts, acting without thinking and sexual promiscuity
- Problems with spatial perception that can result in falls, clumsiness or accidents
- Lack of awareness of one's own behaviors and abilities
- Difficulty focusing on a task for long periods
- Slowness in processing thoughts or "finding" words
- Difficulty in learning new information
Psychiatric Disorders Associated with Huntington’s Disease
The most common psychiatric disorder associated with Huntington's disease is depression. This isn't simply a reaction to receiving a diagnosis of Huntington's disease. Instead, depression appears to occur because of injury to the brain and subsequent changes in brain function. Signs and symptoms may include:
- Feelings of sadness or unhappiness
- Loss of interest in normal activities
- Social withdrawal
- Insomnia or excessive sleeping
- Fatigue, tiredness and loss of energy
- Feelings of worthlessness or guilt
- Indecisiveness, distractibility and decreased concentration
- Frequent thoughts of death, dying or suicide
- Changes in appetite
- Reduced sex drive
Other common psychiatric disorders include:
- Obsessive-compulsive disorder, a condition marked by recurrent, intrusive thoughts and repetitive behaviors
- Mania, which can cause elevated mood, overactivity, impulsive behavior and inflated self-esteem
- Bipolar disorder, or alternating episodes of depression and mania
Other changes in mood or personality, but not necessarily specific psychiatric disorders, may include:
- Irritability
- Apathy
- Anxiety
- Sexual inhibition or inappropriate sexual behaviors
Symptoms of Juvenile Huntington's Disease
The onset and progression of Huntington's disease in younger people may be slightly different from that in adults. Problems that often present themselves early in the course of the disease include:
- Loss of previously learned academic or physical skills
- Rapid, significant drop in overall school performance
- Behavioral problems
- Contracted and rigid muscles that affect gait (especially in young children)
- Changes in fine motor skills that might be noticeable in skills such as handwriting
- Tremors or slight involuntary movements
- Seizures
Treatments for Huntington’s Disease
- Medications
- Psychotherapy
- Speech therapy
- Physical and occupational therapy