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What is AD?
How many Americans have AD?
How long can a person live with AD?
What is dementia?
What is multi-infarct dementia (MID)?
What is mild cognitive impairment (MCI)?
What is
Alzheimer's disease (AD)?
Alzheimer's disease (AD) is the most common form of dementia
(a brain disorder that seriously affects a person's ability to carry
out daily activities) among older people. It involves the parts of
the brain that control thought, memory, and language. Every day
scientists learn more, but right now the causes
of AD are still unknown, and there is no cure.
AD is named
after Dr. Alois Alzheimer, a German doctor. In 1906, Dr. Alzheimer
noticed changes in the brain tissue of a woman who had died of an
unusual mental illness. He found abnormal clumps (now called amyloid
plaques) and tangled bundles of fibers (now called neurofibrillary
tangles). Today, these plaques and tangles in the brain are
considered hallmarks of AD.
Scientists
also have found other brain changes in people with AD. There is a
loss of nerve cells in areas of the brain that are vital to memory
and other mental abilities. There also are lower levels of chemicals
in the brain that carry complex messages back and forth between
nerve cells. AD may disrupt normal thinking and memory by blocking
these messages between nerve cells.
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How many
Americans have AD?
Scientists think that up to 4 million Americans suffer from AD. The
disease usually begins after age 60, and risk goes up with age.
While younger people also may get AD, it is much less common. About
3 percent of men and women ages 65 to 74 have AD, and nearly half of
those age 85 and older may have the disease. It is important to
note, however, that AD is not a normal part of aging.
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How long
can a person live with AD?
AD is a slow disease, starting with mild memory problems and ending
with severe brain damage. The course the disease takes and how fast
changes occur vary from person to person. On average, AD patients
live from 8 to 10 years after they are diagnosed, though the disease
can last for as many as 20 years.
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What is
Dementia?
The term "dementia" describes a group of symptoms that are
caused by changes in brain function. Dementia symptoms may include
asking the same questions repeatedly; becoming lost in familiar
places; being unable to follow directions; getting disoriented about
time, people, and places; and neglecting personal safety, hygiene,
and nutrition. People with dementia lose their abilities at
different rates.
Dementia is
caused by many conditions. Some conditions that cause dementia can
be reversed, and others cannot. The two most common forms of
dementia in older people are Alzheimer's disease
and multi-infarct dementia (sometimes
called vascular dementia). These types of dementia are irreversible,
which means they cannot be cured.
Reversible
conditions with symptoms of dementia can be caused by a high fever,
dehydration, vitamin deficiency and poor nutrition, bad reactions to
medicines, problems with the thyroid gland, or a minor head injury.
Medical conditions like these can be serious and should be treated
by a doctor as soon as possible.
Sometimes
older people have emotional problems that can be mistaken for
dementia. Feeling sad, lonely, worried, or bored may be more common
for older people facing retirement or coping with the death of a
spouse, relative, or friend. Adapting to these changes leaves some
people feeling confused or forgetful. Emotional problems can be
eased by supportive friends and family, or by professional help from
a doctor or counselor.
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What is
Multi-Infarct Dementia (MID)?
In multi-infarct dementia, a series of small strokes or changes in
the brain's blood supply may result in the death of brain tissue.
The location in the brain where the small strokes occur determines
the seriousness of the problem and the symptoms that arise. Symptoms
that begin suddenly may be a sign of this kind of dementia. People
with multi-infarct dementia are likely to show signs of improvement
or remain stable for long periods of time, then quickly develop new
symptoms if more strokes occur. In many people with multi-infarct
dementia, high blood pressure is to blame. One of the most important
reasons for controlling high blood pressure is to prevent strokes.
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What is
Mild Cognitive Impairment (MCI)?
Recently, scientists have focused on a type of memory change called
mild cognitive impairment (MCI). MCI is different from both AD and
normal age-related memory change. People with MCI have ongoing
memory problems but do not have other losses like confusion,
attention problems, and difficulty with language. Scientists funded
by the National Institute on Aging (NIA) are conducting the Memory
Impairment Study to learn whether early diagnosis and treatment of
MCI might prevent or slow further memory loss, including the
development of AD.
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Information
courtesy of Alzheimer's Disease Education & Referral Center
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