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

Alzheimer disease

Alzheimer disease (AD) is a degenerative disease of the brain that causes gradual loss of memory, judgment, and the ability to function socially. Alzheimer disease currently affects about 5 million people.[1] About 75 percent of Alzheimer disease cases are classified as sporadic, which means they occur in people with no history of the disorder in their family. Although the cause of these cases is unknown, genetic changes are likely to play a role. Virtually all sporadic cases of Alzheimer disease begin after age 65, and the risk of developing this condition increases as a person gets older.[2]

AD can be subdivided into two groups based on the age of onset:[3]
(1) Early-onset (1%-6% of the cases) which start in people younger than 60- 65 years of age
(2) Late-onset, which starts in people older than 65 years old.

In about 25% of cases, AD is familial (2 or more people in a family have AD). For more information, please visit GARD's familial Alzheimer disease Web page.
Last updated: 11/2/2015

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 Alzheimer disease. 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.

Patient Registry

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

  • Alzheimer's Association Senior Housing FinderSM, powered by SNAPforSeniors®, is an online senior housing search tool that enables consumers and professionals to:
    • Access a current list of all licensed care facilities 
    • View detailed listings for facilities offering services specific to the needs of residents with Alzheimer's or dementia.
    • Find facilities that match the needs and preferences identified through the Alzheimer's Association CareFinder™.
  • The Social Security Administration has included this condition in their Compassionate Allowances Initiative. This initiative speeds up the processing of disability claims for applicants with certain medical conditions that cause severe disability. More information about Compassionate Allowances and applying for Social Security disability is available online.

Community Resources

  • The Job Accommodation Network (JAN) has information on workplace accommodations and disability employment issues related to this condition. JAN is a service of the Office of Disability Employment Policy in the U.S. Department of Labor.

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

  • Genetics Home Reference (GHR) contains information on Alzheimer disease. This website is maintained by the National Library of Medicine.
  • Mayo Clinic has an information page on Alzheimer disease.
  • 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. 
  • The National Institutes of Health (NIH) has developed a fact sheet on Alzheimer's disease.  To view this fact sheet, click on the link above.

In-Depth Information

  • GeneReviews provides current, expert-authored, peer-reviewed, full-text articles describing the application of genetic testing to the diagnosis, management, and genetic counseling of patients with specific inherited conditions.
  • Medscape Reference provides information on this topic. You may need to register to view the medical textbook, but registration is free.
  • PubMed is a searchable database of medical literature and lists journal articles that discuss Alzheimer disease. 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. Alzheimer Disease. Genetics Home Reference. May, 2013; http://ghr.nlm.nih.gov/condition=alzheimerdisease. Accessed 9/30/2015.
  2. Alzheimer's Facts and Figures. Alzheimer's association. 2015; http://www.alz.org/alzheimers_disease_facts_figures.asp. Accessed 9/30/2015.
  3. Alzheimer Disease Overview. GeneReviews. September 24, 2015; http://www.ncbi.nlm.nih.gov/books/NBK1161/. Accessed 9/30/2015.