Skip secondary menu

NINDS Alzheimer's Disease Information Page


Table of Contents (click to jump to sections)


Listen to this page using ReadSpeaker


What is Alzheimer's Disease?

Alzheimer's disease (AD) is an age-related, non-reversible brain disorder that develops over a period of years. Initially, people experience memory loss and confusion, which may be mistaken for the kinds of memory changes that are sometimes associated with normal aging. However, the symptoms of AD gradually lead to behavior and personality changes, a decline in cognitive abilities such as decision-making and language skills, and problems recognizing family and friends. AD ultimately leads to a severe loss of mental function. These losses are related to the worsening breakdown of the connections between certain neurons in the brain and their eventual death. AD is one of a group of disorders called dementias that are characterized by cognitive and behavioral problems. It is the most common cause of dementia among people age 65 and older.

There are three major hallmarks in the brain that are associated with the disease processes of AD.

  • Amyloid plaques, which are made up of fragments of a protein called beta-amyloid peptide mixed with a collection of additional proteins, remnants of neurons, and bits and pieces of other nerve cells.
  • Neurofibrillary tangles (NFTs), found inside neurons, are abnormal collections of a protein called tau. Normal tau is required for healthy neurons. However, in AD, tau clumps together. As a result, neurons fail to function normally and eventually die.
  • Loss of connections between neurons responsible for memory and learning. Neurons can't survive when they lose their connections to other neurons. As neurons die throughout the brain, the affected regions begin to atrophy, or shrink. By the final stage of AD, damage is widespread and brain tissue has shrunk significantly.

Is there any treatment?

Currently there are no medicines that can slow the progression of AD. However, four FDA-approved medications are used to treat AD symptoms. These drugs help individuals carry out the activities of daily living by maintaining thinking, memory, or speaking skills. They can also help with some of the behavioral and personality changes associated with AD. However, they will not stop or reverse AD and appear to help individuals for only a few months to a few years. Donepezil (Aricept), rivastigmine (Exelon), and galantamine (Razadyne) are prescribed to treat mild to moderate AD symptoms. Donepezil was recently approved to treat severe AD as well. The newest AD medication is memantine (Namenda), which is prescribed to treat moderate to severe AD symptoms.

What is the prognosis?

In very few families, people develop AD in their 30s, 40s, and 50s. This is known as "early onset" AD. These individuals have a mutation in one of three different inherited genes that causes the disease to begin at an earlier age. More than 90 percent of AD develops in people older than 65. This form of AD is called "late-onset" AD, and its development and pattern of damage in the brain is similar to that of early-onset AD. The course of this disease varies from person to person, as does the rate of decline. In most people with AD, symptoms first appear after age 65.

We don't yet completely understand the causes of late-onset AD, but they probably include genetic, environmental, and lifestyle factors. Although the risk of developing AD increases with age, AD and dementia symptoms are not a part of normal aging. There are also some forms of dementia that aren't related to brain diseases such as AD, but are caused by systemic abnormalities such as metabolic syndrome, in which the combination of high blood pressure, high cholesterol, and diabetes causes confusion and memory loss.

What research is being done?

The National Institute of Neurological Disorders and Stroke (NINDS) supports basic and translational research related to AD through grants to major medical institutions across the country. Current studies are investigating how the development of beta amyloid plaques damages neurons, and how abnormalities in tau proteins create the characteristic neurofibrillary tangles of AD. Other research is exploring the impact of risk factors associated with the development of AD, such as pre-existing problems with blood flow in the blood vessels of the brain. Most importantly, the NINDS supports a number of studies that are developing and testing new and novel therapies that can relieve the symptoms of AD and potentially lead to a cure.

On May 15, 2012 the Obama Administration announced the release of the National Alzheimer’s Plan. U.S. Secretary of Health and Human Services Kathleen Sebelius reaffirmed our nation’s commitment to conquering Alzheimer’s disease and related dementias, with a specific goal of finding effective ways to prevent and treat the disease by 2025.

NIH Patient Recruitment for Alzheimer's Disease Clinical Trials

Organizations

Column1 Column2
Alzheimer's Disease Education and Referral Center (ADEAR)
National Institute on Aging
P.O. Box 8250
Silver Spring, MD   20907-8250
adear@nia.nih.gov
http://www.nia.nih.gov/alzheimers
Tel: 1-800-438-4380
Fax: 301-495-3334

National Institute of Mental Health (NIMH)
National Institutes of Health, DHHS
6001 Executive Blvd. Rm. 8184, MSC 9663
Bethesda, MD   20892-9663
nimhinfo@nih.gov
http://www.nimh.nih.gov
Tel: 301-443-4513/866-415-8051 301-443-8431 (TTY)
Fax: 301-443-4279

Alzheimer's Association
225 North Michigan Avenue
Floor 17
Chicago, IL   60601-7633
info@alz.org
http://www.alz.org
Tel: 312-335-8700 1-800-272-3900 (24-hour helpline) TDD: 312-335-5886
Fax: 866.699.1246

Alzheimer's Foundation of America
322 Eighth Avenue
7th Floor
New York, NY   10001
info@alzfdn.org
http://www.alzfdn.org
Tel: 866-AFA-8484 (232-8484)
Fax: 646-638-1546

National Organization for Rare Disorders (NORD)
55 Kenosia Avenue
Danbury, CT   06810
orphan@rarediseases.org
http://www.rarediseases.org
Tel: 203-744-0100 Voice Mail 800-999-NORD (6673)
Fax: 203-798-2291

Family Caregiver Alliance/ National Center on Caregiving
785 Market St.
Suite 750
San Francisco, CA   94103
info@caregiver.org
http://www.caregiver.org
Tel: 415-434-3388 800-445-8106
Fax: 415-434-3508

Association for Frontotemporal Degeneration (AFTD)
Radnor Station Building #2 Suite 320
290 King of Prussia Road
Radnor, PA   19087
info@theaftd.org
http://www.theaftd.org
Tel: 267-514-7221 866-507-7222

National Family Caregivers Association
10400 Connecticut Avenue
Suite 500
Kensington, MD   20895-3944
info@thefamilycaregiver.org
http://www.thefamilycaregiver.org
Tel: 800-896-3650
Fax: 301-942-2302

Well Spouse Association
63 West Main Street
Suite H
Freehold, NJ   07728
info@wellspouse.org
http://www.wellspouse.org
Tel: 800-838-0879 732-577-8899
Fax: 732-577-8644

National Respite Network and Resource Center
800 Eastowne Drive
Suite 105
Chapel Hill, NC   27514
http://www.archrespite.org
Tel: 919-490-5577 x222
Fax: 919-490-4905

American Health Assistance Foundation
22512 Gateway Center Drive
Clarksburg, MD   20871
info@ahaf.org
http://www.ahaf.org/alzheimers/
Tel: 301-948-3244 800-437-AHAF (2423)
Fax: 301-258-9454

National Hospice and Palliative Care Organization /Natl. Hospice Foundation
1731 King Street
Alexandria, VA   22314
nhpco_info@nhpco.org
http://www.nhpco.org
Tel: 703-837-1500 Helpline: 800-658-8898
Fax: 703-837-1233

Alzheimer’s Drug Discovery Foundation
57 West 57th Street
Suite 904
New York, NY   10019
info@alzdiscovery.org
http://www.alzdiscovery.org
Tel: 212-901-8000
Fax: 212-901-8010

John Douglas French Alzheimer's Foundation
11620 Wilshire Blvd.
Suite 270
Los Angeles, CA   90025
http://www.jdfaf.org
Tel: 310-445-4650
Fax: 310-479-0516

Lewy Body Dementia Association
912 Killian Hill Road, S.W.
Lilburn, GA   30047
lbda@lbda.org
http://www.lbda.org
Tel: Telephone: 404-935-6444 LBD Caregiver Link: 800-539-9767
Fax: 480-422-5434

 
Related NINDS Publications and Information
Publicaciones en Español


Prepared by:
Office of Communications and Public Liaison
National Institute of Neurological Disorders and Stroke
National Institutes of Health
Bethesda, MD 20892



NINDS health-related material is provided for information purposes only and does not necessarily represent endorsement by or an official position of the National Institute of Neurological Disorders and Stroke or any other Federal agency. Advice on the treatment or care of an individual patient should be obtained through consultation with a physician who has examined that patient or is familiar with that patient's medical history.

All NINDS-prepared information is in the public domain and may be freely copied. Credit to the NINDS or the NIH is appreciated.

Last updated December 31, 2012