Dementia with Lewy Bodies

  • Medical Author: Howard A Crystal, MD
  • Medical Editor: Helmi L Lutsep, MD

What Is Lewy Body Dementia (LBD)?

Dementia with Lewy bodies (LBD) is a type of dementia caused by the presence of Lewy bodies in the brain.
Dementia with Lewy bodies (LBD) is a type of dementia caused by the presence of Lewy bodies in the brain.

Dementia is a progressive (gradually worsening) decline of mental abilities that disturbs "cognitive" functions such as memory, thought processes, and speech as well as behavior, and movements.

Dementia with Lewy bodies (LBD) is the name for a group of disorders in which dementia is caused by the presence of Lewy bodies in the brain.

  • Lewy bodies are small round clumps of normal proteins that for unknown reasons become abnormally clumped together inside neurons (brain cells).
  • Whether the Lewy bodies directly cause gradual degeneration (damage) to the brain cells, impairing their function and eventually killing them, or are only a marker of some other destructive process is not known.
  • Lewy bodies are named after Frederich Lewy, the doctor who first described them in 1912. Dr. Lewy first found Lewy bodies in the brains of people with Parkinson's disease.

What are the first signs of Lewy body dementia?

  • Parkinson's disease is a condition best known for disrupting body movements.
    • The most common of these "motor" symptoms are tremor (shaking or trembling) of the hands (that mainly occurs when the hands are at rest and not moving),
    • rigidity (stiffness) of the trunk and limbs,
    • slowness of movement, and
    • loss of balance and coordination.
    • Estimates vary about what percentage of people with Parkinson disease develop dementia.
  • Scientists later discovered cases of Alzheimer's-type dementia linked to Lewy bodies. This was thought to be very rare, but as tests of brain tissue improved, it became clear that Lewy bodies were fairly common and were linked to several different types of dementia.

How does Lewy body dementia differ from Alzheimer's?

  • A type of dementia similar to but different from Alzheimer's disease was recognized and called dementia with Lewy bodies. Dementia with Lewy bodies is now believed to be the second or third most common type of dementia after Alzheimer's disease. (There is controversy about whether dementia with Lewy bodies or vascular dementia is the second most common form of dementia.)

What are the dementia with Lewy body causes?

We do not know why Lewy bodies form in the brain.

How does Lewy body dementia progress?

  • The relationship between dementia with Lewy bodies and Parkinson's disease is not completely understood. When motor symptoms appear first and predominate over cognitive symptoms, the diagnosis is believed to be Parkinson disease. When cognitive impairment and behavioral disturbances are prominent early symptoms, dementia with Lewy bodies is believed to be the diagnosis.
  • Dementia with Lewy bodies is a disease of aging. People affected by dementia with Lewy bodies are usually elderly or in late middle age.

What Are the Symptoms of Dementia with Lewy Bodies?

Symptoms vary from person to person with dementia with Lewy bodies. The one characteristic common to everyone with dementia with Lewy bodies is progressive loss of mental abilities that interferes with everyday activities. This may include the following:

  • Loss of recent memory
  • Inability to concentrate or pay attention
  • Difficulty thinking, reasoning, solving problems
  • Misperceptions of space and time

Mental function usually varies in dementia with Lewy bodies, getting better and worse over time. Although the sharpness of our mental function varies in everyone - we all have our good moments and bad moments, or are "morning" persons or "evening" persons - this fluctuation is especially dramatic in dementia with Lewy bodies. This is especially true of alertness and attention.

A person with dementia with Lewy bodies typically has periods of being alert, coherent, and oriented that alternate with periods of being confused and less responsive. This usually is considered more characteristic of dementia with Lewy bodies than of other types of dementia. Other symptoms include the following:

  • Abnormal movements of Parkinson's disease (shuffling gait, tremor, muscle stiffness)
  • Visual hallucinations
  • Depression
  • Nonvisual hallucinations (hearing, smell, touch)
  • Delusions
  • Agitation
  • Unexplained fainting
  • Sensitivity to "neuroleptic" drugs given to control hallucinations and delusions

None of these symptoms are unique to dementia with Lewy bodies or definitively point to dementia with Lewy bodies as a diagnosis. In fact, people with dementia with Lewy bodies often are very difficult to distinguish from those with Alzheimer's disease.

People with dementia with Lewy bodies, however, often develop both Alzheimer's symptoms and Parkinson's symptoms within 1 year of each other.


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How Is Lewy Body Dementia Diagnosed?

  • Dementia symptoms can have many different causes. Some underlying causes are reversible with treatment, others are not, but treatment is often still helpful.
  • It is very important that all reversible causes be ruled out and that the type of dementia is diagnosed correctly, as treatment and outlook vary by type.
  • At this time, there is no foolproof way to confirm dementia with Lewy bodies in a living person. Definitive diagnosis of dementia with Lewy bodies is possible only after death.
  • Examination of brain tissue at autopsy is the only way to confirm the presence of Lewy bodies.
  • Certain chemical tests are applied to the tissue. One test detects alpha-synuclein, the major protein component of the Lewy bodies.
  • Therefore, dementia with Lewy bodies is what medical professionals call a "clinical diagnosis." This means that the diagnosis is made on the basis of your symptoms, your medical history, your test results, and in some cases even your response to treatment.
  • This method is based on detecting signs that may be very subtle and on the probabilities of your having a specific condition.
  • If you or a loved one is having dementia symptoms, your health care provider's job is to gather all the relevant information to make an accurate diagnosis.
  • The first step is the medical interview. You will be asked questions about your symptoms and how they have developed over time, your medical problems now and in the past, medications, family medical problems, work and travel history, and habits and lifestyle.
  • If you have trouble answering the questions, a family member or friend may be asked to fill in missing details. A thorough physical examination, including a mental status examination, will look for signs that might indicate the underlying cause of the dementia.

Neuropsychological Testing

There is no definitive medical test that confirms dementia or dementia with Lewy bodies. The most accurate way to measure cognitive decline is through neuropsychological testing.

  • The testing involves answering questions and performing tasks that have been carefully designed for this purpose. It is carried out by a specialist in this kind of testing. Neuropsychological testing assesses cognitive abilities such as memory, attention, orientation to time and place, use of language, and abilities to carry out various tasks and follow instructions.
  • Reasoning, abstract thinking, and problem solving are tested.
  • Neuropsychological testing gives a more accurate diagnosis of the problem and thus can help in treatment planning.
  • The first test results are used as a baseline for measuring changes in cognitive abilities. The tests may be repeated periodically to see how well treatment is working and check for new problems.

Lab Tests

There is no specific lab test for dementia with Lewy bodies. Lab tests of your blood may be needed to rule out certain causes of dementia, such as infection, metabolic disorders (such as thyroid imbalance), or medication effects. Basic tests may be done to check your overall level of general health.

Imaging Studies

An imaging study of the brain is useful in determining the underlying cause of dementia. MRI is sometimes preferred to CT scan

Other Tests

  • Electroencephalography (EEG) measures brain waves. People with dementia with Lewy bodies sometimes have abnormal waves that can help in the diagnosis. This test is not used routinely, however.
  • Lumbar puncture (spinal tap) with testing of spinal fluid may be used to rule out infection and certain other reversible disorders. Again, however, this test is not done routinely.

What Is the Treatment for Dementia with Lewy Bodies?

There is no cure or treatment that stops or slows dementia with Lewy bodies. Treatment is aimed at relieving symptoms and delaying loss of mental abilities for as long as possible.

An individual with dementia with Lewy bodies should always be under medical care. Much of the day-to-day care, however, is handled by family caregivers. Medical care should focus on optimizing the individual’s health, safety, and quality of life while helping family members cope with the many challenges of caring for a loved one with dementia with Lewy bodies.

How Do You Care for Lewy Body Dementia at Home?

People with dementia with Lewy bodies usually can remain at home with their families. They require close supervision because they can fall or faint. They should be checked often by their medical team to monitor the effects of treatment and make changes if needed.

Individuals with dementia with Lewy bodies should remain physically, mentally, and socially active as long as they are able.

  • Daily physical exercise helps maximize body and mind functions and maintains a healthy weight.
  • The individual should engage in as much mental activity as he or she can handle. Puzzles, games, reading, and safe hobbies and crafts are good choices. These activities should ideally be interactive
  • Social interaction is stimulating and enjoyable for most people with dementia with Lewy bodies. Most senior centers or community centers have scheduled activities that are suitable for those with dementia.

A balanced diet that includes plenty of fruits and vegetables will help maintain a healthy weight and prevent malnutrition and constipation. An individual with dementia with Lewy bodies should not smoke, both for health and safety reasons.

What Is the Medical Treatment for Dementia with Lewy Bodies?

Drug treatment is the mainstay of therapy for dementia with Lewy bodies. The treatment of dementia with Lewy bodies is much like that of Alzheimer's disease or Parkinson's disease.

  • Acetylcholinesterase inhibitors may decrease confusion and cognitive fluctuations in dementia with Lewy bodies. These drugs generally do not worsen motor symptoms. These drugs also may be used for treatment of agitation and hallucinations associated with dementia with Lewy bodies. (When these symptoms are mild, however, no medical treatment may be necessary.)
  • An atypical neuroleptic (antipsychotic) drug typically is the first choice for treatment of hallucinations and agitation. Treating these symptoms is especially important because they can result in unsafe behavior, accidents, and injuries. Standard antipsychotic drugs such as haloperidol (Haldol) should be avoided because many people with dementia with Lewy bodies are extremely sensitive to these drugs.
  • Drugs that increase levels of the neurotransmitter dopamine are widely used to relieve the motor symptoms of Parkinson's disease. These drugs may improve motor function in some people with dementia with Lewy bodies. In many people, however, these drugs have no effect and may make cognitive symptoms worse, especially hallucinations.
  • Depression is very common in dementia with Lewy bodies and may result from brain damage and/or as a psychological response to impaired function. Selective serotonin reuptake inhibitors (SSRIs) are the drugs of choice. Another type of antidepressant called a monoamine oxidase-B inhibitor (MAOI) has been tried, alone or in combination with SSRIs or tricyclic antidepressants. Such combinations are not usually recommended because they can have severe side effects, especially in older people.
  • Some research studies have suggested that vitamin E, an antioxidant, may slow the rate of progression of Alzheimer's disease. Therefore, vitamin E has been tried in dementia with Lewy bodies. We do not yet have proof that this agent works in dementia with Lewy bodies.

What Are the Medications for Dementia with Lewy Bodies?

Medications can be used to relieve depression, treat agitation and hallucinations, and improve cognition and/or alertness. There is a great deal of controversy about whether or not acetylcholinesterase inhibitors may slow the rate of cognitive decline or slow the need for nursing home placement.

Acetylcholinesterase inhibitors: These drugs increase the level of acetylcholine in the brain, which is low in dementia with Lewy bodies. These drugs can decrease fluctuations in cognition, increase alertness, and improve memory. Examples include:

Atypical neuroleptics: These drugs can relieve hallucinations, delusions, and agitation. They do not worsen motor symptoms as much as "typical" older neuroleptic drugs do. Examples include:

Antidepressants: The first choice for treatment of depression in dementia with Lewy bodies is the selective serotonin reuptake inhibitors, which do not deplete acetylcholine. Examples include:

Dopamine-promoting drugs: These drugs work in various ways to increase the level of the neurotransmitter dopamine in the brain. Although low dopamine level is partly responsible for the motor symptoms of dementia with Lewy bodies, these drugs often cannot be tolerated because of the side effects. They can, for example, worsen hallucinations. Examples include combined levodopa and carbidopa (Sinemet), which combines a dopamine precursor with a drug that maximizes its usefulness in the brain, and pramipexole (Mirapex) and ropinirole (Requip), which mimic the effects of dopamine.

Antioxidants: These agents counteract excess oxidation, which may contribute to the brain cell damage in dementia with Lewy bodies. Formal studies are lacking to determine their usefulness in slowing the disease progression. The only example now in widespread use is alpha-tocopherol, or vitamin E (Vita-Plus E Softgels, Vitec, Aquasol E).

What Is the Follow-up for Dementia with Lewy Bodies?

After dementia with Lewy bodies has been diagnosed and treatment begun, the individual requires regular check-ups with his or her health-care professional.

  • These check-ups allow the health-care professional to see how well treatment is working and make adjustments as necessary.
  • They allow detection of new medical and behavior problems that could benefit from treatment.
  • These visits also give the family caregiver(s) an opportunity to discuss problems in the individual’s care.

Eventually the person with dementia with Lewy bodies will become unable to care for himself or herself, or even to make decisions about his or her care.

  • It is best for the person to discuss future care arrangements with family members as early as possible, so that his or her wishes can be clarified and documented for the future.

Your health-care professional can advise you about legal arrangements that should be made to ensure that these wishes are observed.

How Do You Prevent Dementia with Lewy Bodies?

There is no known way to prevent dementia with Lewy bodies. Being alert for symptoms and signs may allow earlier diagnosis and treatment. Appropriate treatment can slow or relieve symptoms in some people.

What Is the Prognosis for Dementia with Lewy Bodies?

Like other types of degenerative dementia such as Alzheimer's disease, dementia with Lewy bodies is gradually progressive.

  • Dementia with Lewy bodies eventually affects a person's job performance. Many people with dementia with Lewy bodies take early retirement from their jobs.
  • The person with dementia with Lewy bodies will eventually lose his or her ability to drive safely. Driving privileges should be addressed by the caregivers and care team.
  • Eventually the person will lose the ability to care for himself or herself.
  • Dementia with Lewy bodies shortens life expectancy.

The rate of progression varies considerably, but most people die within 5-7 years after their disease is diagnosed. The cause of death is usually a complication of the disease.

  • People with the disease develop severe dementia and eventually may have only limited ability to move.
  • They are at risk of falls because of poor balance and walking difficulties.
  • Many have difficulties swallowing, which leads to poor nutrition and sometimes pneumonia (because food goes into the lungs instead of the stomach).
  • They eventually become immobile, which can lead to skin problems, pneumonia, and other complications.

Where Can Lewy Body Dementia Caregivers Get Counseling and Support?

If you are a caregiver for a person with dementia with Lewy bodies, you know that the disease tends to be more stressful for the family members than for the affected person.

Caring for a person with dementia can be very difficult. It affects every aspect of your life, including family relationships, work, financial status, social life, and physical and mental health.

  • You may feel unable to cope with the demands of caring for a dependent, difficult relative.
  • Besides the sadness of seeing the effects of your loved one’s disease, you may feel frustrated, overwhelmed, resentful, and angry.
  • These feelings may in turn leave you feeling guilty, ashamed, and anxious.
  • Depression is not uncommon but usually gets better with treatment.

Caregivers have different thresholds for tolerating these challenges.

  • For many caregivers, just “venting” or talking about the frustrations of caregiving can be enormously helpful.
  • Others need more support, but may feel uneasy about asking for the help they need.
  • One thing is certain, though: if the caregiver is given no relief, he or she can burn out, develop his or her own mental and physical problems, and become unable to care for the affected person.

This is why support groups were invented. Support groups are groups of people who have lived through the same difficult experiences and want to help themselves and others by sharing coping strategies.

Mental health professionals strongly recommend that family caregivers take part in support groups. Support groups serve a number of different purposes for a person living with the extreme stress of being a caregiver for a person with dementia with Lewy bodies:

  • The group allows the person to express his or her true feelings in an accepting, nonjudgmental atmosphere.
  • The group’s shared experiences allow the caregiver to feel less alone and isolated.
  • The group can offer fresh ideas for coping with specific problems.
  • The group can introduce the caregiver to resources that may be able to provide some relief.
  • The group can give the caregiver the strength he or she needs to ask for help.

Support groups meet in person, on the telephone, or on the Internet. To find a support group that works for you, contact the following organizations. You can also ask your health care provider or behavior therapist, or go on the Internet. If you do not have access to the Internet, go to the public library. For more information about support groups, contact these agencies:

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