What is Alzheimer’s Disease?
Alzheimer’s disease is the most common form of dementia among older
adults. Alzheimer’s disease involves parts of the brain that control
thought, memory, and language and can seriously affect a person’s ability to
carry out daily activities. Although scientists are learning more every day,
right now, they still do not know what causes Alzheimer’s disease.
Who has Alzheimer’s Disease?
As many as 5 million Americans suffer from Alzheimer’s disease. While
younger people may get Alzheimer’s disease, it is much less common. The
disease usually begins after age 60, and risk goes up with age. About 5
percent of men and women ages 65 to 74 have Alzheimer’s disease, and nearly
half of those age 85 and older may have the disease. It is important to
note, however, that Alzheimer’s disease is not a normal part of aging.
What causes Alzheimer’s Disease?
Scientists do not yet fully understand what causes Alzheimer’s disease.
There probably is not one single cause, but several factors that affect each
person differently. Age is the most important known risk factor for
Alzheimer’s disease. The number of people with the disease doubles every 5
years beyond age 65.
Family history is another risk factor. Researchers believe that genetics
may play a role in developing Alzheimer’s disease.
Scientists still need to learn a lot more about what causes Alzheimer’s
disease. In addition to genetics, they are studying education, diet, and
environment to learn what role they might play in developing this disease..
Scientists are finding more and more evidence that some of the risk factors
for heart disease and stroke, such as high blood pressure, high cholesterol,
and low levels of the vitamin folate may also increase the risk of
Alzheimer’s disease. Evidence for physical mental and social activities as
protective factors against Alzheimer’s disease is also growing.
What is the burden of Alzheimer’s disease in the United States?
Alzheimer’s disease is one of the top ten leading causes of death in the
United States. Alzheimer’s disease has recently surpassed diabetes as the
6th leading cause of death among American adults. Notably, mortality rates
for Alzheimer’s disease are on the rise, unlike heart disease and cancer
death rates which are continuing to decline.
An estimated 5 million Americans have Alzheimer’s disease. This number
has doubled since 1980, and is expected to be as high as 13.4 million by
In 2005, total Medicare spending for individuals with Alzheimer’s disease
was estimated at $91 billion.
Individuals with Alzheimer’s disease make up less than 13 percent of the
Medicare population, yet they account for 34 percent of Medicare spending.*
*Reference: Urban Institute, unpublished tabulations from the 2000
Medicare Current Beneficiary Survey and Medicare Claims, 2005; published by
the Alzheimer’s Association, Alzheimer’s Disease Facts and Figures, 2007.
Where can I find more information about Alzheimer’s disease?
The National Institutes of Health
The National Library of Medicine
The Alzheimer’s Disease Education and Referral (ADEAR) Center
For additional resources on aging and cognitive health, please visit:
CDC Healthy Brain Initiative
CDC Healthy Aging Program
The National Institute on Aging
* Links to non-federal
organizations are provided solely as a service to our users. Links do not
constitute an endorsement of any organization by CDC or the federal
government, and none should be inferred. The CDC is not responsible for
the content of the individual organization Web pages found at this link.
last reviewed: September 25, 2008
Page last modified: September 25, 2008
Content source: Division of Adult
and Community Health, National Center for Chronic Disease Prevention and