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.
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.
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.
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Alzheimer's Disease Education and Referral Center (ADEAR)
P.O. Box 8250
National Institute of Mental Health (NIMH)
6001 Executive Blvd. Rm. 8184, MSC 9663
National voluntary health organization committed to finding a cure for Alzheimer’s and helping those affected by the disease.
Alzheimer's Foundation of America
Works to provide optimal care and services to individuals confronting dementia and to their caregivers and families thruogh member organizations dedicated to improving quality of life.
Association for Frontotemporal Degeneration (AFTD)
Nonprofit organization that promotes and funds research into finding the cause and cure for frontotemporal degeneration, also called frontotemporal dementia (FTD); provides information, education, and support to those affected by FTD and their caregivers; and sponsors professional health education programs related to FTD.
290 King of Prussia Road
Non-profit charitable organization dedicated to funding research and educating the public on Alzheimer's disease, glaucoma, and macular degeneration.
Alzheimer’s Drug Discovery Foundation
Public charity whose mission is to accelerate the discovery and development of drugs to prevent, treat, and cure Alzheimer's disease, related dementias, and cognitive aging.
John Douglas French Alzheimer's Foundation
Provides seed money for novel and innovative Alzheimer's research at major California universities. Unsolicited applications and/or letters of inquiry not accepted.
Lewy Body Dementia Association
Supports those affected by Lewy body dementias through outreach, education and research.
National Organization for Rare Disorders (NORD)
Federation of voluntary health organizations dedicated to helping people with rare "orphan" diseases and assisting the organizations that serve them. Committed to the identification, treatment, and cure of rare disorders through programs of education, advocacy, research, and service.
Family Caregiver Alliance/ National Center on Caregiving
Supports and assists families and caregivers of adults with debilitating health conditions. Offers programs and consultation on caregiving issues at local, state, and national levels. Offers free publications and support online, including a national directory of publicly funded caregiver support programs.
National Respite Network and Resource Center
Information and referral service that assists and promotes the development of quality respite and crisis care programs; helps families locate respite and crisis care services in their communities; and sponsors advocacy and awareness efforts concerning respite care.
National Hospice and Palliative Care Organization /Natl. Hospice Foundation
Non-profit membership organization representing hospice and palliative care programs and professionals. Provides free referrals to the public for hospice listings across the United States and internationally. Distributes free packets of general information describing hospice services and the Medicare Hospice Benefit.
Caregiver Action Netork (formerly National Family Caregiver Association)
Grassroots organization dedicated to supporting and improving the lives of America's family caregivers. Created to educate, support, empower, and advocate for the millions of Americans who care for their ill, aged, or disabled loved ones.
Well Spouse Association
International non-profit, volunteer-based organization whose mission is to provide emotional support to, raise consciousness about, and advocate for the spouses/partners of the chronically ill and/or disabled.
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NINDS Disorders is an index of neurological conditions provided by the National Institute of Neurological Disorders and Stroke (NINDS). This valuable tool offers detailed descriptions, facts on treatment and prognosis, and patient organization contact information for over 250 identified neurological disorders.