Lewy body dementia (LBD) is a progressive disease involving atypical deposits of protein called alpha-synuclein in the brain. These changes can affect a person’s thinking, behavior, mood, and movement.

The deposits are what Lewy bodies are made of, and are named after Friedrich H. Lewy, the scientist who discovered them.

According to the National Institute on Aging (NIA), LBD affects more than 1 million people in the United States, with early symptoms seen typically at age 50 or over. However, it is sometimes still seen in younger adults.

There are two types of LBD: Parkinson’s disease (PD) dementia and dementia with Lewy bodies. Both are due to the decline of two brain messengers, or neurotransmitters: dopamine and acetylcholine. The accumulation of the Lewy bodies causes decline.

LBD is the second most common cause of dementia, after Alzheimer’s disease.

Let’s look into the disease to learn more.

It is remarkable how similar LBD, PD, and Alzheimer’s disease (AD) are in their symptoms, causes, and treatment.

This table illustrates the symptoms they share. But they are just a small part of the symptoms experienced by those affected.

LBD• decline in thinking
• memory loss
• mood changes
• poor sense of direction
• impaired problem solving
• difficulty walking
• hallucinations
• medication sensitivity
• REM sleep behavior disorder
• buildup of Lewy bodies in the brain
• lower production of dopamine and acetylcholine
•no cure

PD• tremors
• slowed movement
• rigidity
• decline in thinking
• memory loss
• mood changes
• poor sense of direction
• impaired problem solving
• difficulty walking
• hallucinations
• medication sensitivity
• REM sleep behavior disorder
• buildup of Lewy bodies in the brain
• lower production of dopamine and acetylcholine
•no cure


AD• decline in thinking
• memory loss
• mood changes
• poor sense of direction
• impaired problem solving
• age-related changes to the brain
• blood vessel damage
• energy breakdown between the cells
• plaques and tangles in the brain
•no cure



LBD has many symptoms. As the disease progresses or continues to grow, the symptoms worsen.


Your brain is constantly thinking, remembering, and reasoning. Dementia occurs when it loses its ability to do this, according to the NIA. You may notice it starting to interfere with your daily activities and life.

Minor signs of dementia may include forgetting you paid a bill or repeating questions. Then, as it progresses, you may wander away from home or be unable to recognize the faces of loved ones.


Besides dementia, you will experience other changes in your mental status that include:

  • inability to concentrate
  • trouble holding attention
  • decreased alertness
  • drowsiness


When you hallucinate, you see things that aren’t real, even though they feel very real in your mind. Sometimes, this can be very scary.

For example, you may hear voices or see something that isn’t there.


Like PD, LBD may cause you to experience slow movements, challenges with walking, and muscle stiffness.

Your posture may also change to a slouch or slump.


Many LBD patients experience rapid eye movement (REM) sleep behavior disorder. This irregular sleep pattern is a condition where you experience vivid dreams that cause you to:

  • talk in your sleep
  • fall out of bed
  • move, sometimes violently, while sleeping

This symptom may be one of the earliest signs of LBD.


As mentioned before, with LBD, you may experience disinterest in daily activities or doing the things you used to love. You may also have feelings of depression, irritability, and anxiety.

Research has yet to uncover the root cause of LBD. Scientists aren’t sure what prompts the proteins to build up in the first place.

A 2021 study found that genetics may play a vital role in the development of LBD. The same genetics found in LBD are also seen in PD and AD.

Not everyone with PD will develop LBD, but having Parkinson’s may increase your risk of LBD.

A 2016 review indicates as many as 78 percent of PD patients experience dementia, and it is more likely as you age. LBD tends to affect people over 55 years old.

The same study identified additional risk factors for LBD in PD. They include:

  • male gender
  • changes in posture
  • instability with walking
  • greater difficulty with movement
  • symptoms seen on the left and right sides of the body
  • experiencing hallucinations earlier
  • symptoms not responding to medication

Early diagnosis is essential because some drugs used to treat PD and AD can worsen LBD. However, early diagnosis is not easy, since no single test can accurately diagnose LBD.

Here are some of the exams and tests that can help your doctor arrive at the correct diagnosis.

Physical exam

When you visit a neurologist, they will perform a physical exam. A neurologist is a doctor who specializes in treating nervous system conditions. They’ll test the different ways your brain responds and how well it is working.

Physical examination may include testing of:

  • heart rate and blood pressure
  • muscle tone and strength
  • reflexes
  • balance and coordination
  • sense of touch
  • eye movements

Review of medical history

Sometimes, a review of your medical history can tell them some of the most important things they need to know. For example, it would be helpful for you and a loved one to both report the symptoms you’ve experienced. It’s helpful to have a loved one give their account of your symptoms to give the doctor more context. Doctors need all the details possible to ensure an accurate diagnosis.

Blood tests

Blood testing rules out and looks for definitive signs of disease, according to the NIA. Your doctor may want to check your protein levels to see if they are atypical. They may also test for other conditions that cause similar symptoms to rule out all possibilities.

Neurological testing

The neurologist will run various tests to check your physical functioning, reflexes, and thinking. They may also conduct a:

  • memory test
  • language skills test
  • math skills test
  • balance check
  • sensory test

Any variations here can be a sign of dementia.

Brain scans

Imaging tests might include MRI, CT, or positron emission tomography (PET) scans. They can identify any changes to the structure of your brain and its function.

These tests also help the physicians rule out other neurological diseases that may cause similar symptoms, such as stroke or cancer.

Sleep test

Your doctor may want to perform a sleep test to look at your brain function. As they monitor your sleep, they look for signs of REM sleep behavior disorder.

Autonomic function testing

Your autonomic nervous system is the part of your brain and nerves that controls how you move or react without thinking. It controls:

  • breathing
  • blood pressure levels
  • heartbeat
  • digestion of food
  • regulation of body temperature

Testing will help look for problems in its functioning caused by LBD.

The Alzheimer’s Association says that at first, symptoms of LBD may be mild. You may be able to function as you did before. However, as the condition progresses, the symptoms worsen until you cannot care for yourself without help.

Early stage

Later stage

  • forgetting loved ones
  • wandering from home
  • aggressive behavior
  • severe tremors
  • depression
  • violent mood swings
  • inability to walk

End stage

  • inability to care for yourself
  • inability to communicate

There’s no treatment to slow or stop disease progression. However, treatment is recommended to better manage your symptoms and improve your quality of life.


People with LBD tend to be very sensitive to drugs. Therefore, physicians must prescribe medications with great caution and careful monitoring, according to the National Institute of Neurological Disorders and Stroke (NINDS).

Medications used for symptom management include:

  • donepezil (Namzaric), which can treat memory, mood, and hallucinations
  • rivastigmine (Exelon), which can treat memory, mood, and hallucinations
  • levodopa with carbidopa (Sinemet), which can manage tremors and slowness
  • low dose clonazepam (Klonopin), which can treat sleep disturbances
  • melatonin, a natural hormone, which can treat sleep disturbances

In some cases, antipsychotics may be prescribed for hallucinations, delusions, or paranoia, but with extreme caution. Antipsychotics can worsen symptoms of LBD. Severe side effects can be life threatening.


A typical treatment plan may include one or more of the following:

  • Physical therapy. This can help improve gait, strength, flexibility, and overall health.
  • Occupational therapy. This can help make everyday tasks such as eating and bathing easier, requiring less assistance from others.
  • Speech therapy. This can help improve problems with swallowing and speaking.
  • Mental health counseling. This can help both the person with LBD and their family learn to cope with their emotions and behaviors.

Complementary therapies

Alternative treatments for LBD include:

  • Vitamins and supplements. Studies of vitamins and supplements in people with LBD are lacking. And because they can interact with medications, it’s important to consult your doctor before using them.
  • Art and music therapy.This may help ease anxiety and improve mood, according to a 2018 review.
  • Family care and support. With training and support, both the caregiver and their patient experience less stress with less severe mood changes and other psychiatric symptoms.
  • Sensory stimulation. Engaging the senses can reduce agitation in people with LBD.

There’s no way to stop the progression of LBD. It will continue to affect the brain and body, leading to lifelong medical care. Medications can manage symptoms, but they must be monitored and adjusted as needed.

A person with LBD will need the assistance provided by family and professional caregivers. According to the NINDS, the average life expectancy is 8 years after symptoms begin, similar to Alzheimer’s disease.

The role of the caregiver is likely to grow as the disease progresses. Of course, every situation is different. But here are some general tips from the NIA for caregivers of people with LBD.

Educate others

LBD is a disease that many people, including physicians and nurses, may not be familiar with. However, once you start to understand the progression of the disease and the rules for medications, you’ll want to speak up and ensure your loved one isn’t in danger.

If you take them to receive medical care, make sure the staff understands their diagnosis of LBD and their sensitivity to medication. You may also suggest they consult a neurologist before prescribing any new medications.

It is also a good idea to educate your family and friends about LBD. You will need their continued support, and it is best they have a good grasp on your loved one’s needs.

Expect the unexpected

Caring for a loved one with LBD will be challenging for you. However, you may find some days are easier than others.

Listen to your mind and body to find your strengths and weaknesses. Remain realistic about what you can and can’t do for them. Understand you may need others to help with their care. You have to feel comfortable asking for help.

Observe and learn

The disease affects individuals differently. It is best to observe what works and doesn’t work for them. Do they prefer quiet rooms or enjoy a noisy environment? Do they like their senses stimulated with a particular candle’s smell or a soft blanket? Finding what they like can help give them a better quality of life.

Expect changes in behavior

There are several reasons why someone with LBD may become angry, act out with aggression, or seem depressed. Understand that it is a part of their disease. It is best not to meet anger with even more anger on your part.

Remain patient, identify the cause of their mood change, and do your best to respond. Your loved one may need changes to their environment or even medications to help treat symptoms.

Care for the caregiver

It’s easy to get lost in caregiving, to the detriment of your own health and well-being. But you can’t do your best for someone else if you don’t take care of yourself.

Try to follow these self-care tips:

  • Ask for help. Reach out to family, friends, neighbors, or in-home healthcare professionals.
  • Take time off to do something for yourself. Socialize with your friends, schedule a massage, or plop on the sofa and stream a movie. “Me time” matters.
  • Get regular exercise, even if it’s just a walk around the neighborhood.
  • Maintain a balanced diet so your own health doesn’t get derailed.
  • Take periodic time out for deep breathing and quiet meditation or soothing music.
  • Contact your own doctor when you start to feel out of whack.

Caregiver burnout is all too real. It doesn’t mean you’ve failed, it only means you’re stretching yourself too thin. You might find it helpful to join a caregiver support group so you can interact with people who get it. If you start to feel emotionally or physically drained, consider speaking with a therapist.

What are the first signs of Lewy body dementia?

According to Medline Plus, REM sleep behavior disorder is often the first sign of LBD. Then, you start to notice changes in your mental processing.

What is the life expectancy of someone with Lewy body dementia?

The average life expectancy of a person with LBD is 5 to 8 years after diagnosis.

Is Lewy body dementia fatal?

The Alzheimer’s Association says that there is no cure for LBD. As it progresses, it will become fatal.

What’s the average onset age for Lewy body dementia?

LBD tends to affect people aged 50 and up.

Lewy body dementia is the second most common type of dementia. The process and progression of LBD are similar to Parkinson’s disease and Alzheimer’s disease.

There may not be a cure for this disease, but there are ways to treat its symptoms and improve the quality of life for those living with it.