National Center for Advancing and Translational Sciences Genetic and Rare Diseases Information Center, a program of the National Center for Advancing and Translational Sciences

Lewy body dementia

Not a rare disease Not a rare disease
Other Names:
Lewy body disease; DLB; Diffuse Lewy body disease; Lewy body disease; DLB; Diffuse Lewy body disease; Autosomal dominant diffuse Lewy body disease See More
Lewy body dementia is one of the most common forms of progressive dementia. People affected by this condition may experience a variety of symptoms such as changes in alertness and attention; hallucinations; problems with movement and posture; muscle stiffness; confusion; and/or memory loss. Although the exact cause of Lewy body dementia is poorly understood, symptoms are thought to result when clumps of a protein called alpha-synuclein ("Lewy bodies") accumulate in the brain. Lewy body dementia usually occurs sporadically in people with no family history of the condition. Rarely, more than one family member may be affected. There is currently no cure for Lewy body dementia; however, medications may be available to help manage the associated symptoms.[1][2][3]
Last updated: 11/5/2015

This table lists symptoms that people with this disease may have. For most diseases, symptoms will vary from person to person. People with the same disease may not have all the symptoms listed. This information comes from a database called the Human Phenotype Ontology (HPO) . The HPO collects information on symptoms that have been described in medical resources. The HPO is updated regularly. Use the HPO ID to access more in-depth information about a symptom.

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Medical Terms Other Names
Learn More:
HPO ID
Percent of people who have these symptoms is not available through HPO
Autosomal dominant inheritance 0000006
Delusions 0000746
Dementia
Dementia, progressive
Progressive dementia
[ more ] 		0000726
Fluctuations in consciousness 0007159
Lewy bodies 0100315
Parkinsonism 0001300
Visual hallucinations 0002367
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Last updated: 7/1/2020
The exact underlying cause of Lewy body dementia is poorly understood. The symptoms of the condition are thought to occur when clumps of a protein called alpha-synuclein accumulate in the regions of the brain involved in thinking, memory and movement. The build-up of these clumps (which are called "Lewy bodies") appears to be associated with a loss of certain neurons (nerve cells) in the brain that produce two important neurotransmitters (chemicals that act as messengers between brain cells). The neurotransmitter, acetylcholine, is important for memory and learning. The other, dopamine, plays an important role in behavior, cognition, movement, motivation, sleep, and mood.[4]

Although Lewy body dementia usually occurs sporadically, more than one family member can rarely be affected. Studies of these families suggest that there may be a genetic component to the condition in some cases. For example, copy number variants or changes (mutations) in the SNCA gene have been reported in a few affected families.[5][6] The APOE ε4 allele and mutations in the GBA gene have been associated with an increased risk of Lewy body dementia and the APOE ε2 allele with a decreased risk.[5][7][2]
Last updated: 11/5/2015
Most cases of Lewy body dementia are not thought to be inherited. The condition generally occurs sporadically in people with no family history of the condition.[4]

Rarely, the condition can affect more than one family member. Some of these cases appear to be due to single gene changes (mutations) that follow an autosomal dominant pattern of inheritance. Other familial cases do not follow a specific pattern of inheritance and likely have a multifactorial cause (associated with the effects of multiple genes in combination with lifestyle and environmental factors).[6][5]
Last updated: 11/6/2015

Making a diagnosis for a genetic or rare disease can often be challenging. Healthcare professionals typically look at a person’s medical history, symptoms, physical exam, and laboratory test results in order to make a diagnosis. The following resources provide information relating to diagnosis and testing for this condition. If you have questions about getting a diagnosis, you should contact a healthcare professional.

Testing Resources

  • The Genetic Testing Registry (GTR) provides information about the genetic tests for this condition. The intended audience for the GTR is health care providers and researchers. Patients and consumers with specific questions about a genetic test should contact a health care provider or a genetics professional.
The Lewy Body Dementia Association offers detailed and up-to-date information regarding the treatment and management of Lewy body dementia. Please click on the link to access this resource.
Last updated: 11/6/2015

If you need medical advice, you can look for doctors or other healthcare professionals who have experience with this disease. You may find these specialists through advocacy organizations, clinical trials, or articles published in medical journals. You may also want to contact a university or tertiary medical center in your area, because these centers tend to see more complex cases and have the latest technology and treatments.

If you can’t find a specialist in your local area, try contacting national or international specialists. They may be able to refer you to someone they know through conferences or research efforts. Some specialists may be willing to consult with you or your local doctors over the phone or by email if you can't travel to them for care.

You can find more tips in our guide, How to Find a Disease Specialist. We also encourage you to explore the rest of this page to find resources that can help you find specialists.

Healthcare Resources

Research helps us better understand diseases and can lead to advances in diagnosis and treatment. This section provides resources to help you learn about medical research and ways to get involved.

Clinical Research Resources

  • ClinicalTrials.gov lists trials that are related to Lewy body dementia. Click on the link to go to ClinicalTrials.gov to read descriptions of these studies.

    Please note: Studies listed on the ClinicalTrials.gov website are listed for informational purposes only; being listed does not reflect an endorsement by GARD or the NIH. We strongly recommend that you talk with a trusted healthcare provider before choosing to participate in any clinical study.

Support and advocacy groups can help you connect with other patients and families, and they can provide valuable services. Many develop patient-centered information and are the driving force behind research for better treatments and possible cures. They can direct you to research, resources, and services. Many organizations also have experts who serve as medical advisors or provide lists of doctors/clinics. Visit the group’s website or contact them to learn about the services they offer. Inclusion on this list is not an endorsement by GARD.

Organizations Supporting this Disease

Living with a genetic or rare disease can impact the daily lives of patients and families. These resources can help families navigate various aspects of living with a rare disease.

Financial Resources

These resources provide more information about this condition or associated symptoms. The in-depth resources contain medical and scientific language that may be hard to understand. You may want to review these resources with a medical professional.

Where to Start

  • Mayo Clinic has an information page on Lewy body dementia.
  • MedlinePlus was designed by the National Library of Medicine to help you research your health questions, and it provides more information about this topic.
  • The National Institute of Neurological Disorders and Stroke (NINDS) collects and disseminates research information related to neurological disorders. Click on the link to view information on this topic.
  • The National Institute on Aging (NIA) leads a national program of research on the biomedical, social, and behavioral aspects of the aging process; the prevention of age-related diseases and disabilities; and the promotion of a better quality of life for all older Americans. Click on the link to view information on this topic. 

In-Depth Information

  • Medscape Reference provides information on this topic. You may need to register to view the medical textbook, but registration is free.
  • Online Mendelian Inheritance in Man (OMIM) is a catalog of human genes and genetic disorders. Each entry has a summary of related medical articles. It is meant for health care professionals and researchers. OMIM is maintained by Johns Hopkins University School of Medicine. 
  • Orphanet is a European reference portal for information on rare diseases and orphan drugs. Access to this database is free of charge.
  • PubMed is a searchable database of medical literature and lists journal articles that discuss Lewy body dementia. Click on the link to view a sample search on this topic.

Questions sent to GARD may be posted here if the information could be helpful to others. We remove all identifying information when posting a question to protect your privacy. If you do not want your question posted, please let us know.

  1. Dementia With Lewy Bodies Information Page. National Institute of Neurological Disorders and Stroke (NINDS). November 2015; https://www.ninds.nih.gov/Disorders/All-Disorders/Dementia-Lewy-Bodies-Information-Page.
  2. Crystal HA. Dementia With Lewy Bodies. Medscape Reference. April 2014; http://emedicine.medscape.com/article/1135041-overview#a4.
  3. Lewy Body Disease. MedlinePlus. October 2015; https://www.nlm.nih.gov/medlineplus/lewybodydisease.html.
  4. Lewy Body Dementia: Information for Patients, Families, and Professionals. National Institute on Aging. September 2015; https://www.nia.nih.gov/alzheimers/publication/lewy-body-dementia/introduction.
  5. DEMENTIA, LEWY BODY. OMIM. December 2012; http://www.omim.org/entry/127750.
  6. Farlow MR. Epidemiology, pathology, and pathogenesis of dementia with Lewy bodies. UpToDate. January 2015; https://www.uptodate.com/contents/epidemiology-pathology-and-pathogenesis-of-dementia-with-lewy-bodies.
  7. Dementia with Lewy body. Orphanet. December 2012; http://www.orpha.net/consor/cgi-bin/OC_Exp.php?lng=en&Expert=1648.