Dementia
is a broad term that refers to a progressive cognitive decline,
especially marked by memory deficit. The symptoms may include
memory deficits, impaired abstract thinking, poor judgment,
disorientation, depression,
agitation and nervousness, and sleep disorders. In the late
stages of the disease, patients become dependent on caregivers
for the activities of daily living, including eating, dressing
and bathing. Dementia itself is not directly fatal, but patients
may die of complications associated with immobility or reduced
resistance to infectious diseases such as pneumonia.
Alzheimer's
disease is the most prevalent type of dementia. Dementia
may also be caused indirectly by brain tumors, head injury,
viral inflammation, substance abuse, syphilis, long-term epilepsy,
etc. Dementia is also a component of the late stages of Parkinson's
disease, Huntington's disease and AIDS, and may also appear
in individuals who are chronic abusers of alcohol. In some
cases (e.g. Alzheimer's disease), symptoms progress gradually
over a course of years; in others (e.g. vascular
dementia), symptoms appear over a relatively short period
of time and may appear to worsen in increments.
Normally, when a patient is diagnosed with dementia, doctors
first attempt to establish whether the dementia is associated
with some pre-existing disease or condition such as Parkinson's
disease or substance abuse, or with some trauma such as head
injury or stroke. Other conditions such as depression and
sleep disorder can also cause memory deficits and other cognitive
problems superficially related to dementia. A diagnosis of
probable Alzheimer's disease is only made after other causes
of dementia are ruled out, while a definite diagnosis of Alzheimer's
disease can only be made at autopsy.
by Catherine E. Myers. Copyright © 2006 Memory Loss and the Brain |
