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Lewy body dementia

Lewy body dementia, also known as LBD, is the second most common type of dementia after Alzheimer’s disease. Protein deposits called Lewy bodies develop in nerve cells in the brain. The protein deposits affect brain regions involved in thinking, memory and movement. There are two forms of LBD that cause cognitive symptoms — dementia with Lewy bodies and Parkinson’s disease dementia.

Lewy body dementia causes a decline in mental abilities that gradually gets worse over time. People with LBD might see things that aren’t there, known as visual hallucinations. They also may have changes in alertness and attention.

People with Lewy body dementia commonly have symptoms of Parkinson’s disease. These symptoms might include rigid muscles, slow movement, trouble walking and tremors.

Lewy body dementia symptoms can include:

In people with Lewy body dementia, there’s a buildup of proteins known as Lewy bodies. This protein also is associated with Parkinson’s disease. People who have Lewy bodies in their brains also can have the plaques and tangles associated with Alzheimer’s disease.

A few factors seem to increase the risk of developing Lewy body dementia, including:

Lewy body dementia is progressive. This means it gradually gets worse over time. As symptoms get worse, the disease can lead to:

People who are diagnosed with Lewy body dementia, also known as LBD, have a gradual decline in the ability to think. They also have at least two of the following:

Other symptoms that support a Lewy body dementia diagnosis include problems with the autonomic nervous system. When this happens, the body isn’t able to regulate blood pressure, heart rate, body temperature and sweating.

Sensitivity to medicines that treat psychosis also supports a diagnosis. This is particularly true for medicines such as haloperidol (Haldol). Antipsychotic medicines aren’t used for people with LBD because they can make symptoms worse.

No single test can diagnose Lewy body dementia. The diagnosis is based on your symptoms and by ruling out other conditions. You might need the following tests.

Neurological and physical exam

Your healthcare professional may check for signs of Parkinson’s disease, strokes, tumors or other conditions. A neurological exam tests:

Test of mental abilities

A short form of this test, which assesses memory and thinking skills, can be done in less than 10 minutes. The test doesn’t usually distinguish between Lewy body dementia and Alzheimer’s disease. But the test can determine whether you have cognitive impairment. Longer tests that take several hours also help identify LBD.

Blood tests

These can rule out physical causes of changes in brain function, such as vitamin B-12 deficiency or an underactive thyroid gland.

Brain scans

Your healthcare professional might order an MRI or CT scan to look for signs of a stroke or bleeding and to rule out a tumor. Dementias are diagnosed based on medical history and physical exam, but imaging results can suggest whether someone has Alzheimer’s disease or LBD.

If the diagnosis is unclear or the symptoms aren’t typical, you may need other imaging tests. These imaging tests may support a diagnosis of Lewy body dementia:

Sleep test

You may need a sleep test called a polysomnogram to check for REM sleep behavior disorder.

Autonomic function test

You may need a test that checks if your heart rate, blood pressure or other automatic functions are stable.

Heart test

In some countries, healthcare professionals also might order a heart test called myocardial scintigraphy. This checks the blood flow to your heart for signs that might point to Lewy body dementia. However, the test isn’t used in the United States.

Emerging biomarkers

Studies are ongoing into other indicators of Lewy body dementia. Groups are studying a test that detects clumps of proteins linked to LBD called alpha-synuclein in samples of cerebrospinal fluid obtained through a spinal tap. They’re also testing skin samples for alpha-synuclein in people with Lewy body dementia. These biomarkers are currently available but not yet widely used. They might eventually enable early diagnosis of Lewy body dementia before the full disease develops.

There’s no cure for Lewy body dementia, also known as LBD, but many of the symptoms can improve with targeted treatments.

Medicines

These medicines can help improve Lewy body dementia symptoms.

Certain medicines can worsen memory. Don’t take sleep aids that contain diphenhydramine (Advil PM, Aleve PM) or medicines that treat urinary urgency, such as oxybutynin (Oxytrol).

Limit sedatives and sleeping medicines. Talk to a healthcare professional about whether any of the medicines you take might make your memory worse.

Antipsychotic medicines can cause very bad confusion, movement symptoms, sedation and sometimes death in people with LBD. Very rarely, certain second-generation antipsychotics, such as quetiapine (Seroquel) or clozapine (Clozaril, Versacloz) might be prescribed for a short time at a low dose. But they’re offered only if the benefits outweigh the risks.

Therapies

Because antipsychotic medicines can worsen LBD symptoms, it might be helpful to first try other approaches, such as:

Symptoms and how quickly they worsen are different for everyone with Lewy body dementia. Caregivers and spouses of people with Lewy body dementia, known as care partners, may need to adapt the following tips:

Limit caffeine during the day. Discourage daytime napping and offer activities to stay active during the day. This might help prevent nighttime restlessness.

Frustration and anxiety can worsen dementia symptoms. To promote relaxation, consider:

People with Lewy body dementia often have a mixture of emotions. The person may feel confused, frustrated, angry or afraid. They may not be certain about the future and may feel grief and depression. Offer support by listening. Provide assurance that the person can still enjoy life. Be positive and do your best to help the person retain dignity and self-respect.

If you’re a caregiver or care partner for someone with Lewy body dementia, watch the person closely. Make sure the person doesn’t fall, lose consciousness or have a bad reaction to medicines. Provide reassurance during times of confusion, delusions or hallucinations.

Looking after yourself

Caring for a person with Lewy body dementia can be exhausting physically and emotionally. You may have anger, guilt, frustration, discouragement, worry, grief or social isolation. Help prevent caregiver burnout by:

Many people with Lewy body dementia and their families benefit from counseling or local support groups. Contact your local agencies on health or aging to connect with support groups, healthcare professionals, resources and referrals. They also can recommend home care agencies, supervised living facilities, a phone help line and educational seminars.

You might first discuss your symptoms with a healthcare professional who may refer you to a doctor trained in dementia. This is usually a doctor trained in brain and nervous system conditions, called a neurologist, or a doctor trained in mental health conditions, called a psychiatrist.

Ask a friend or family member to come to the appointment, if possible. This person can help you remember the information you’re given and give your healthcare professional information about you. Here’s some information to help you get ready for your appointment.

What you can do

Make a list of:

What to expect from your doctor

You, your spouse, partner or close friend are likely to be asked a number of questions about:

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