What is Huntington’s Disease (HD)

h-huntingtons-disease-hdHuntington disease is an inherited disease that causes the progressive deterioration or degeneration of nerve cells in the brain. Huntington’s disease has a large impact on an individual’s ability to functions including movement, cognitive ability and psychiatric disorder.

As the disease advances,  jerky, uncoordinated, body movements grow more obvious.Physical abilities gradually worsen until coordinated movement becomes difficult and the person is unable to talk. Mental abilities often decline into dementia. The specific symptoms vary somewhat between people

The majority of people with Huntington in disease develop signs and symptoms in their 30s or 40s, yet have the onset of the disease later or earlier in life. There are cases when the onset happens before the age of 20, causing what is considered juvenile Huntington’s disease. Earlier the onset of the disease the will tend to result in a different set of symptoms and faster disease progression.

Some medications are available to help manage the symptoms of Huntington’s disease, but treatment can not stop the physical, mental and behavioral decline that is the outcome of this disease.

Huntington Disease Symptoms

Huntington is disease will usually cause cognitive, psychiatric and movement disorders. There is a wide range of signs and symptoms. Such symptoms appear fist varies significantly among those who are affected. During the stages of the disease, some disorders seem to dominate more or have a greater significant effect on functional ability.

Movement Disorders

  • The movement disorders linked with Huntington’s disease can involve both involuntary movements and impairments in voluntary movements.
  • Involuntary jilting or writhing movements (chorea)
  • Issues with muscle, rigidity muscles, problems with contracture dystonia.
  • Slow or abnormal eye movements
  • Difficulty speaking or swallowing
  • Impaired gait, posture, and balance.

Research has shown that substance abuse has a strong effect on the age of onset of motor symptoms in Huntington disease.
Patients who abused tobacco, alcohol, and drugs encountered the onset of motor symptoms several years earlier than patients who did not. The effect of substance abuse was very strong in women.

Out of a sample group of 4,1146 participants with Huntington’s disease, 2314 ha motor-skill affected by Huntington’s disease. After eliminating patients with an unreported age on onset of motor symptoms, patients with onset at 21 or younger, patients who did not fit any substance abuse category and patients with a diagnosis confidence of zero 1849 participants were evaluated. Whereas 466 abused tobacco, 374 abused alcohol, and 217 abused drugs and 692 did not abuse any substances.
Patines who abused tobacco had an early onset of symptoms 2.3 earlier, patines who abused alcohol one year earlier and patients who abused drugs 3.3 years earlier

Cognitive disorders

Cognitive impairments often linked to Huntington’s disease include;
challenge organizing, focusing and prioritizing task.

  • Lack of flexibility or prone to getting stuck on thoughts behavior or actions(preservation)
  • Lack of awareness of one’s behavior or abilities
  • Difficulty learning new things
  • Slowness to process thought or words to communicate
  • Lake of impulse control, having an outburst or acting without thinking secual
  • promiscuity.

huntington-s-disease-medical-illustration-symptoms-brain-68174452Psychiatric disorders

The are common psychiatric disorders associated with Huntington’s disease is depression.This is not simply a reaching to the diagnoses of Huntington’s disease. Instead, depression appears to occur because of injury to the brain or subsequent changes in brain function. Signs and symptoms may include the following:

  • Feeling or irritability sadness or apathy
  • Insomnia
  • Social withdrawal
  • Fatigue and loss of energy
  • Frequent thoughts of dying or death.

There are common psychiatric disorders including:

Obsessive-compulsive disorder, a condition characterized by recurrent, and intrusive thoughts and repetitive behaviors.
Mania – This is triggered by elevated mood, over-activity impulsive behavior, and inflated self-esteem.
Bipolar disorder, alternate episodes of mania and depression.

Symptoms of juvenile Huntington’s disease
The onset and progression of Huntington disease in younger people may be slightly different from that of adults. Challenges that often present themselves early in the course of the disease include:

  • Behavioral changes
  • Loss or previous learned academic or physical skills
  • Behavioral problems
  • Rapid, a significant drop in overall school performance.

autosomal-dominantPhysical changes
Contracted and rigid muscles that affect gait (especially in young children)
Tremor or slight involuntary movements
Changes in the motor skills that might be noticeable in skills such as handwriting

You should see a doctor when you notice changes in your movements or emotional state or mental ability. The signs and symptoms of Huntington disease can be caused by a number or current conditions.

Causes of Huntington’s disease

Huntington’s disease is created by an inherited defect in a single gene. Huntington’s disease is an autosomal dominant disorder, which indicates that a person requires only one copy of the defective gene to produce the disorder.

Except for genes on sex chromosomes, a person will inherit two copies of every gene, one copy from each parent. A parent with a defective Huntington gene can pass along a defective copy to or a health copy. HD is mostly inherited from a person’s parents, with 10% of cases caused by a new mutation. The disease is triggered by an autosomal dominant mutation in either of a person’s two copies of a gene referred to as Huntingtin Each child in the family has a 50% percent chance of inheriting the gene that causes the genetic disorder. The Huntingtin gene stores the genetic information for a protein that is also also called “huntingtin”.

Expansion of CAG (cytosine-adenine-guanine) triplet recurs in the gene coding for the Huntingtin protein which results in an abnormal protein, which gradually destroys cells in the brain, through mechanisms that are not fully recognized

Complications of Huntington’s Disease

After the onset of Huntington;’s disease, a person’s functional ability will slowly worsen over time. The rate of disease progression and duration will vary. The time from disease onset to death is normally 10 to 30 years. Juvenile onset usually results in death within ten years.

The clinical depression associated with Huntington disease may increase the risk of suicide. Some research suggests that the risk is higher for suicide broke a diagnose is made and in the middle stages of the disease when an individual begins to lose their independence.

Over time, a person with Huntington’s disease needs help with all activities of daily living and care. Later in the disease, he or she will likely be considered to the bed and unable to communicate. However, he or she will likely be able to understand language and has an awareness of the family and friends.

hd-n-normal-brainCommon causes of death include
Complications related to the inability to swallow.
Injuries related to falls
Pneumonia or other infections.

Test and Diagnosis of Huntington’s disease.

A diagnosis of Huntington’s disease is based on answering several questions, general physical examination, review of family medical history, and neurological and psychiatric exams.

Neurological examination
The neurologist will ask you a series of question, simple test in the office can be used to evaluate:

  • Motor symptoms:
  • Balance
  • Muscle tone
  • Coordination
  • Muscle strength
  • Reflexes

Sensory symptoms

  • Sense of touch
  • Hearing
  • Vision and eye movement

Psychiatric symptoms

  • Mood
  • Mental status

Neuropsychological testing
The neurologists may also perform test to assess the following

  • Memory
  • Reasoning
  • Language function
  • Spatial reasoning
  • Mental agility

Psychiatric evaluation
You will be referred to psychiatry to examine and evaluate the number of factors that could contribute to the diagnosis.

  • Patterns of behavior
  • Coping skills
  • Evidence of substance abuse
  • Signs of disordered thinking
  • Emotional state

Brian imaging and function

Your doctor may order a brain-imaging test for assessing the structure or function of the brain. The imaging technologies may include an MRI; which can produce detailed cross-sectional and 3-D images of the brain or CT scan
These images may reveal structural schemas at particular sites in the brain affected by Huntington disease however these changes may not be apparent early in the course of the disease. The test can also be used to rule out other conditions that may be causing symptoms.

Genetic counseling and testing

If symptoms strongly suggest an analysis of Huntington’s disease, your doctor may recommend a genetic evaluation for the detective genetics. This test can confirm the diagnosis, and it may is important if there’s no observed family history of Huntington’s disease or if no other family member’s diagnosis was established with a genetic test

The test will not provide information that is beneficial in determining a treatment plan.

Before you have a test, the genetic console may explain the benefits and drawbacks of learning the test results. The genetic counselor can answer any question about the inheritance patterns of Huntington’s disease.

Predictive genetic test
A genetic test can be given to an individual who has a family history of the disease but the show, not signs or symptoms. This is referred to as predictive testing. The test result has not retreatment benefit; it does not indicate when disease onset will begin or what symptoms are most likely to appear first.

Some people may elect to do the because they find it more stressful not knowing. Ther may want to take the test before they make decisions about having children.
The risk may induce problems with insurability or future employment and the stress of facing a fatal disease. This test is the only period of consultation with a genetic counselor

Medication for Huntington Disease

Treatments and Drugs

There are no treatments that can change the course of Huntington’s disease. However he medication can lessen some symptoms of movement and psychiatric disorders. Ther are multiple interventions can help a person adapt to changes his or her abilities for a certain amount of time.

Medication management is needed, and will evolve over time over the course of the disease, depending on the overall treatment goals. Alos drugs o treat some symptoms that may result in side effects that worsen other symptoms.
Treatment goals and plans will need to be reviewed and updated.

Medication for movement disorders

Drugs to treat movement disorders include the following:

Tetrabenazine (Xenazine) this drug is approved by the Food and Drug Administration to suppress the involuntary jerking and writhing movements called chorea linked with Hunton;s diseases, A serious die effect is a risk of worsening triggering depression of other psychiatric conditions.

Antipsychotic drugs, such as haloperidol (HaldorL) and chlorpromazine, have a side effect of controlling movements. Accordingly, they may be beneficial in treating chorea. These drugs may prevent involuntary contractions (dystonia) and muscle rigidity.
Newer drugs such as riper Dio dnd *Risperdal) and quetiapine (Seroquel) can have fewer side effects but still should be handled with caution, and they may worsen symptoms.

Other medications that may help suppress chorea include amantadine, levetiracetam (Keppra) and clonazepam (Klonopin) At high dose, Amantadine can exacerbate the cognitive effects of Huntington’s disease. It can also produce skin discoloration and leg swelling
Side effects of levetiracetam include mood swings, nausea, and upset stomach. Clonazepam may worsen the cognitive side effects of Huntington’s disease and cause drowsiness. It also has a high risk of dependency and abuse,

Medications for psychiatric disorders

Medications to treat psychiatric disorder will vary depending on the disorders and symptoms. Possible treatments include the following.
Antidepressants include medications such as Celexa Lexapro) fluoxetine (Prozac, Sarafem) and sertraline(Zoloft). These drugs may also have some effect on managing the obsessive-compulsive disorder. Side effects can include nausea, diarrhea, drowsiness and low blood pressure
Antipsychotic drugs – such as quetiapine (Seroquel) risperidone (Risperdal) and olanzapine (Zyprexa) – may subdue violent out its agitation, and other symptoms of mood disorder or psychosis. However, these drugs may cause different movement disorders themselves.
Mood stabling drugs that can help counteract the highs and lows associated with bipolar disorder involve anticonvulsants, such as carbamazepine (Carbatrol, Epitol, Equetro) valproate (Depacon) and lamotrigine ( Lamictal) General side effects include weight gain, tremor, and gastrointestinal problems.

Psychotherapy – A psychotherapist – a psychiatrist, psychologist or clinical social worker – can present talk therapy to help a person control behavioral problems, develop coping strategies, manage expectations during the progression of the disease and frailty effective communication among family members.
Speech therapy
Huntington;s disease can dramatically diminish control of muscles of the mouth and throat that are necessary for speech, eating and swallowing. A speech therapist can help enhance your ability to speak effectively or teach you to use communication devices- such as a board covered with pictures of everyday items and activities. A speech therapist can also address difficult with muscles used in eating and swallowing.
Physical therapy
A physical therapist can teach you some safe exercises that are appropriate that enhance strength, balance, flexibility and coordination. This exercise can help sustain mobility as long as possible and may reduce the risk of falls.
Instruction on appropriate position and the use of supports to improve posture may help reduce the severity of some mobility problems.
When the use of a walker or wheelchair is needed, the physical therapist can provide instruction on appropriate use of the device and posture. Also, exercise regimens can be adapted to suit the new level of mobility.
Occupation therapy
An occupational therapist can help the person with Huntington;s disease, family members and caregivers on the usage of the assistive device that improves functional abilities. The strategies may include

Handrails at home
Assistive devices of activities such as bathing and dressing
Eating and drinking utensils for people with limited fine motor skills.

Health Life Media Team