Alzheimer`s Disease
Alzheimer’s Disease (AD) is one of the most common of the dementing illnesses. A
progressive, degenerative disease that attacks the brain, causing impaired
memory, thinking and behavior. A person with Alzhiemers Disease may experience
personality and behavior changes, impaired judgment, confusion and difficulty
finishing thoughts, following directions or even finding the right word to say
in a conversation. Once advanced the sufferer may require a caretaker as daily
chores become very difficult to accomplish. Evidence points toward amyloid as
one of the main causes for the occurring cytotoxic processes. Researchers have
found that degeneration appears to be caused by interference with intracellular
calcium homeostasis via activation of calcium channels, intracellular calcium
stores, and further production of free radicals by calcium-sensitive enzymes.
The glutamatergic system seems to be involved in mediating the toxic processes.
In the brain, the nerve cells in the part that controls memory and thinking are
damaged, this interrupts the passage of messages between communicating cells.
The cells undergo distinctive changes, these are called neuritic plaques (groups
of degenerating nerve cell ends) and neurofibrillary tangles (groups of twisted
filaments which accumulate in previously healthy nerve cells). The cortex (used
for thinking) of the brain shrinks, the spaces in the center of the brain become
enlarged causing reduction of the surface area in the brain. Symptoms of AD
usually occur in older adults and are the ones most at risk, although people in
their 40s and 5Os may also be affected. The symptoms include a loss of
intellectual capacity, loss of language skills which may include having trouble
finding words, poor or decreased judgment, problems with abstract thinking,
disorientation in place and time, changes in mood or behavior and changes in
personality. AD does not discriminate, it affects any race, socio background or
sex equally. The classic symptom of forgetfulness is part of the normal aging
process and usually begins in early middle age, however, normal forgetfulness
differs from Alzheimer’s Disease in many important ways. The cause of
Alzheimer’s Disease is not exactly known. Suspected causes undergoing research
are neurological damage, chemical deficiencies, viruses, environmental toxins
and malfunctions in the body’s disease defense systems and genetics. There is
also evidence of a slightly increased risk of heridity of AD amongst children,
brothers and sisters of patients with this disease. It is also important to note
that AD can only be diagnosed 100% after death through an autopsy of the
affected subjects brain tissue. About a third of autopsies turn up a different
diagnosis and thus family members are encouraged to ask for an autopsy as a
contribution to the study of the disease and about the genetics of AD. There is
no single clinical test for AD. It is usually diagnosed by ruling out all other
curable or incurable causes of memory loss. A positive diagnosis of this disease
can only be made by microscopically studying a small piece of brain tissue after
death. The cerebral cortex of an Alzheimer sufferers brain will have
characteristic abnormalities such as cells marred by plaques and tangles. A
working diagnosis can be made though through various testing procedures that
include a complete physical as well as neurological and psychological
examinations. At this time there is no definite cure or treatment for AD,
although there are many suppliers of products which claim to help sufferers, but
the products are more like over-priced placebos with no documented evidence of
alleviation of the illness amongst sufferers, but glutamate receptor-selective
drugs, some antioxidants, nitric oxide synthase inhibitors, calcium channel
antagonists, receptor or enzyme inhibitors, and growth factors promise future
help in curing this disease. Combinations of drugs that act at different levels
may also prolong the sufferers life/health. People diagnosed with Alzheimer’s
Disease can live anywhere from 2 to 20 years after memory loss symptoms start to
surface. It shortens the sufferers expected life span, but through appropriate
care and medical attention the patients oftenlive for many years. Death can’t
usually be predicted until the end stages where symptoms are nearing their
worse. Some patients in late or terminal-stage Alzheimer’s tend to lose weight
and have difficulty swallowing, difficulties with bladder control, walking and
talking. They are also known to curl into a fetal position. Sufferers most often
die through a series of repeated infections such as bladder infections or
pneumonia. Although the following estimations are from American literature, as
explained earlier we know that AD has a more or less universal effect amongst
the populations, ratio wise. Alzheimer’s afflicts approximately 4,000,000
Americans and it’s estimated that one in three of us may have a relative that
will suffer from this degenerative disease. More than 100,000 die annually which
makes AD the fourth largest cause of adult death in the US. It is also a very
costly disease monatary wise in that about half of the patients in nursing homes
have this illness with an estimated $80 billion spent annually on the care of,
diagnosis, treatment, etc. People who suffer from AD often require 24-hour care
and supervision, this is mostly provided by family and friends in a home.
Bibliography
Bliss T. V. P Collingridge G. L (1993) A synaptic model of memory: Long-term
potentiation in the hippocampus, Nature 361 31-39 * Clarris H. J. et al (1994)
Secretion of nerve growth factor from septum stimulates neurite outgrowth and
release of the amyloid protein precursor of Alzheimer’s disease from hippocampal
explants J. Neurosci. Res. 38 248-258 * Disterhoft J. F et al (1994) The calcium
rationale in aging and Alzheimer’s disease Calcium Hypothesis of Aging and
Dementia, Annual Academy of Science. N.Y. New York 382-405 * Holschier,C (1998)
Neurobiology of disease, Academic Press 5 121-159 * http://www.ahaf.org/alzdis/about/adabout.htm
* http://www.alzheimers.com/ * http://www.zarcrom.com/users/yeartorem/index4.html
