퇴행성 뇌질환 - 3. HD(Huntington’s Disease)’s Treatment & Prognosis

▣ HD(Huntington’s Disease)’s Treatment & Prognosis

◈ Treatment

There is no cure for Huntington's disease. Treatment focuses on reducing symptoms, preventing complications, and providing support and assistance to the patient and those close to him or her.

Physicians may prescribe a number of medications to help control emotional and movement problems associated with HD(Huntington’s disease). It is important to remember however, that while medicines may help keep these clinical symptoms under control, there is no treatment to stop or reverse the course of the disease.

Antipsychotic drugs, such as haloperidol, or other drugs, such as clonazepam, may help to alleviate choreic movements and may also be used to help control hallucinations, delusions, and violent outbursts. Antipsychotic drugs, however, are not prescribed for another form of muscle contraction associated with HD, called dystonia, and may in fact worsen the condition, causing stiffness and rigidity. These medications may also have severe side effects, including sedation, and for that reason should be used in the lowest possible doses.

For depression, physicians may prescribe fluoxetine, sertraline, nortriptyline, or other compounds. Tranquilizers can help control anxiety and lithium may be prescribed to combat pathological excitement and severe mood swings. Medications may also be needed to treat the severe obsessive-compulsive rituals of some individuals with HD.

Most drugs used to treat the symptoms of HD have side effects such as fatigue, restlessness, or hyperexcitability. Sometimes it may be difficult to tell if a particular symptom, such as apathy or incontinence, is a sign of the disease or a reaction to medication.

♣ Medication

Physicians often prescribe various medications to help control emotional and movement problems.

☞ Antipsychotics(hallucinations, delusions, violent outbursts): haloperidol, chlorpromazine, olanzapine(contraindicated if patient has dystonia)

☞ Antidepressants(depression, obsessive-compulsive behavior): fluoxetine, sertraline hydrochloride, nortriptyline

☞ Tranquilizers(anxiety, chorea): benzodiazepines, paroxetine, venlafaxin, beta-blockers

☞ Mood-stabilizers(mania, bipolar disorder): lithium, valproate, carbamazepine

☞ Botulinum toxin(dystonia, jaw clenching)

♣ Nutrition and Eating

Some Huntington's disease patients need a lot of time for meals because the loss of coordinated movement can make it difficult for them to swallow or feed themselves. These difficulties put them at risk for choking.

Food can be cut into small pieces, softened, or pureed to make swallowing easier. Swallowing therapy can help if started before there is serious difficulty. Dairy products should be avoided because they tend to increase the secretion of mucus, which can increase the risk for choking.

It is important for the patient to consume enough calories to maintain adequate body weight. The number of daily meals may have to be increased and vitamins and nutritional supplements may be recommended. If eating and dietary problems become severe, families and caregivers may need to consider the use of a feeding tube.

HD patients require large quantities of fluids, especially during hot weather, to avoid dehydration. Bendable straws can make drinking easier. In cases where the patient's muscular capability is severely weakened, water may have to be thickened with additives to the consistency of syrup before drinking is possible.

Complications such as constipation and incontinence can develop as a result of diet and lack of physical activity. A physician can provide dietary advice and information about how to cope with these problems.

♣ Physical Activity

It is important for Huntington's disease patients to be as physically fit as their condition permits. Daily exercise promotes physical and mental well-being. Patients should walk as much as possible, even if assistance is necessary.

Because falls are always a risk, caregivers should keep the patient's surroundings free of hard, sharp objects. Wearing special padding during walks can help protect against injury from falls. Small weights worn around the ankles and sturdy, well-fitting shoes that slip on and off easily can help improve a patient's stability.

♣ Social Activity

Unless and until the disease's progression prohibits it, people with HD should participate in outside activities, socialize, and pursue hobbies and interests. These activities also give family members and caregivers valuable time for themselves.

◈ Prognosis

Huntington's disease usually runs its full terminal course in 10 to 30 years. It has been observed that the earlier in life the symptoms of HD appear, the faster the disease progresses. The bedridden patient in the final stages of Huntington's disease often dies from complications such as heart failure or pneumonia.

Juvenile Huntington's disease runs it course comparatively fast, with death typically occurring in about 10 years.

Since the exact cause of cell loss in HD(Huntington's disease) has not yet been established, only symptomatic treatment is currently available for HD patients. A variety of experimental drugs for HD have been tested at Baylor, but none appear to slow the course of the disease, so the search for true neuroprotective drugs continues.

Xenazine® (tetrabenazine) is the only FDA approved medication for Huntington disease and has been the most effective anti-chorea drug is our experience. Tetrabenazine does not cause tardive dyskinesia, but, similar to other neuroleptics, it may cause slowness of movement, drowsiness, restlessness or mood changes. Prior to the drug's general FDA approval, Dr. Jankovic received special permission(an investigational new drug permit) from the FDA to prescribe tetrabenazine in 1979 and has used the drug has since that time in well over a thousand patients, including those with HD.

Psychosis may improve with neuroleptics(drugs that block dopamine receptors), such as haloperidol, pimozide, fluphenazine, and thioridazine. These drugs, however, can induce tardive dyskinesia(manifested by involuntary movements other than chorea), so they should only be used if absolutely needed to control symptoms. Clozapine, an atypical antipsychotic(neuroleptic) drug that does not cause tardive dyskinesia, may be a useful alternative to the typical neuroleptics, but its risk of agranulocytosis(a very low white cell count) complicates its use. Other atypical neuroleptics such as olanzapine(Zyprexa), quetiapine(Seroquel), and ziprasidone(Geodon) do not need close monitoring and may be easier to use, but are less effective in controlling chorea. Other medications for memory loss, depression and anxiety also may be useful in some HD patients with these problems.

 

The Movement Disorders Clinic at Baylor College of Medicine has been designated as a Center of Excellence by the HD Society of America. It is also a member of the Huntington Study Group, a consortium of academic clinicians and researchers interested in finding the cause of neurodegeneration in HD and designing therapeutic trials of new medications.