ALZHEIMER'S DISEASE
We are currently living in the age of technology. Our advancements in the past
few decades overshadow everything learned in the last 2000 years. With the
elimination of many diseases through effective cures and treatments, Canadians
can expect to live a much longer life then that of their grandparents. In 1900
about 4% of the Canadian population was over the age of 65. In 1989 that figure
tripled to 12% and the government expects that figure to rise to 23% by the
year 2030 (Medical, 1991, p.13). This increase has brought with it a large
increase in diseases associated with old age. Alzheimer's dementia is one of
the most common and feared diseases afflicting the elderly community. AD, once
thought to be a natural part of aging, is a severely debilitating form of
mental dementia. Although some other types of dementia are curable or
effectively treatable, there is currently no cure for the Alzheimer
variety.
A general overview of Alzheimer's disease including the clinical description,
diagnosis, and progression of symptoms, helps one to further understand the
treatment and care of patients, the scope of the problem, and current
research.
The clinical definition of dementia is "a deterioration in intellectual
performance that involves, but is not limited to, a loss in at least 2 of the
following areas: language, judgement, memory, visual or depth perception, or
judgement interfering with daily activities" (Institute, 1996, p.4).
The initial cause of AD symptoms is a result of the progressive deterioration
of brain cells (neurons) in the cerebral cortex of the brain. This area of the
brain, which is the largest and uppermost portion, controls all our thought
processes, movement, speech, and senses. This deterioration initially starts in
the area of the cortex that is associated with memory and then progresses into
other areas of the cortex, then into other areas of the brain that control
bodily function. The death of these cells causes an interruption of the
electrochemical signals between neurons that are a key to cognitive as well as
bodily functioning.
Currently AD can only be confirmed at autopsy. After death the examined brain
of an Alzheimer victim shows two distinct characteristics. The first is the
presence of neuritic plaques in the cerebral cortex and other areas of the
brain including cerebral blood vessels. These plaques consist of groups of
neurons surrounded by deposits of beta-amyloid protein. The presence of these
plaques is also common to other types of dementia.
The second characteristic, neurofibliary tangles, is what separates AD from all
other forms of dementia. Neurofibliary tangles take place within the
disconnected brain cells themselves. When examined under a microscope diseased
cells appear to contain spaghetti-like tangles of normally straight nerve
fibers. The presence of these tangles was first discovered in 1906 by the
German neurologist Alois Alzheimer, hence the name Alzheimer's disease.
Although the characteristics listed above are crucial to the diagnosis of AD
upon death, the clinical diagnosis involves a different process. The diagnosis
of AD is only made after all other illnesses, which may have the same symptoms,
are ruled out. The initial symptoms of AD are typical of other treatable
diseases therefore doctors are hesitant to give the diagnosis of Alzheimer's in
order to save the patient from the worsening of a treatable disease through a
misdiagnosis. Some of the initial symptoms include an increased memory loss,
changes in mood, personality, and behavior, symptoms that are common of
depression, prescription drug conflict, brain tumors, syphilis, alcoholism,
other types of dementia, and many other conditions.
The onset of these symptoms usually brings the patient to his family doctor.
The general practitioner runs a typical battery of urinalysis and blood tests
that he sends off to the lab. If thetests come back negative, and no other
cause of the symptoms is established, the patient is then refereed to a
specialist. The specialist, usually a psychiatrist, will then continue to rule
out other possible illnesses through testing. If the next battery of tests also
comes back negative then the specialist will call on a neurologist to run a
series of neurological examinations including a PET and CAT scan to rule out
the possibility of brain tumors. A spinal tap is also performed to determine
the possibility of other types of dementias. The patient will also undergo a
complete psychiatric evaluation. If the patient meets the preliminary criteria
for AD an examination of the patients medical history is also necessary to
check for possible genetic predispositions to the disease.
The psychiatric team finally meets with the neurological team to discuss their
findings. If every other possible disease is ruled out, and the results of the
psychiatric evaluation are typical to that of a person with AD, the diagnosis
of Alzheimer's disease is given.
The initial symptoms of AD are usually brushed off as a natural part of aging.
The myth that a person's memory worsens over time is just that - a myth (Myers,
1996, p.100-101). AD's victims are mostly over the age of 65 and many delay
treatment by attributing their problems to age. A victim might forget a well
known phone number or miss an important appointment. These symptoms eventually
escalate to the total disintegration of personality and all patients end up in
total nursing care. In descending order, the patient goes from
- decreased ability to handle a complex job to
- decreased ability to handle such complex activities of daily life as
- managing finances,
- complex meal preparation and
- complex marketing skills. Next comes
- loss of ability to pick out clothing properly,
- or to put on clothing properly, followed by
- loss of ability to handle the mechanics of bathing properly. Then
- progressive difficulties with continence and
- toileting occur, followed by
- very limited speech ability and
- inability to speak more than a single word. Next comes
- loss of ambulatory capability. Last to go are such basic functions as
- sit up
- smile and
- hold up one's head (Brassard, 1993, p.10).
The average time from diagnosis to inevitable death is 8 years. The family
of the victim is usually able to care for the victim for an average period of
about 4 years (Alzheimer's, 1996, p.44).During the progression of the disease
between 10% and 15% of patients hallucinate and suffer delusions, 10% will
become violent and 10% suffer from seizures (Alzheimer's, 1996, p.46).
Once a person is diagnosed as having AD, an assessment is made of the disease's
stage of progression and of the strengths and weaknesses of the victim and the
victim's family. There are different types of assessments available to evaluate
the level of dysfunction of the patient. Based on one of these assessments a
care plan is put together by a team consisting of a family member, a paid or
unpaid care provider, and the victim's physician. Throughout the progression of
the disease, and depending on the needs of the patient, a wide range of
expensive medication, such as psychoactive drugs to lift depression and
sedatives to control violence, may be required.
Unfortunately, although a wide range of treatments have been tested, most prove
to be ineffective. At the beginning of the disease the family is able to look
after the patient without much effort. Frequently families will hire a care
giver in order to alleviate some of the work.
Simple changes in the home can make life much easier for the sufferer, help
them keep their self esteem, and prolong their stay at home. Examples of
low-cost modifications to the environment include reducing the noise levels in
the home (telephones, radios, voices, etc.); avoiding vividly patterned rugs
and drapes; placing locks up high or down low on doors leading outside (AD
sufferers are known to wander off); clearing floors of clutter; reducing the
contents of closets in order to simplify choices (Alzheimer, 1992, p.17). These
costs are paid for by the victim's family. Many of these, and other more
expensive modifications are introduced in long-term care settings. They help in
maintaining the safety and security of the victim as well as reducing their
confusion.
The patient's and the family's condition should be assessed every six months
(Alzheimer, 1992, p.21). In response to constantly changing needs, the aspects
of care must be constantly modified. Other issues that usually arise during the
care of the patient are assessment of the competence of the victim, power of
attorney, and response to and prevention of abuse (Aronson, 1988, p.124).
Eventually the victim's condition deteriorates to the point where home care is
no longer possible and they must be moved to a long-term care facility.
In Canada care, support and information for victims and their families comes
from the health care system and the Alzheimer's Society of Canada. The care
giver must obtain information and education about the disease in order to
effectively care for the victim. During the course of the disease victims might
wander, hallucinate, become suspicious. This behavior can place a large strain
on the care giver as well as causing depression and deterioration of their own
health (Aronson, 1988, p.132). An AD support group is crucial to alleviating
some of the stress on the care giver. Through a support group the care giver is
given the emotional and practical help needed to accomplish the large task of
looking after the victim for as long as possible.
Currently there are 300,000 persons in Canada with AD. This figure is more than
that of Parkinson's disease, cancer and multiple sclerosis combined. With
continuous growth in the percentage of Canadians over the age of 65, this
figure could hit 700,000 by the year 2020 (Carlton, 1996, p.17). These large
and increasing figures translate into a large burden on the health care system.
Even when using the most conservative estimates of the average number of years
spent in an institution and the number of afflicted Canadians, the costs to
health care are immense. At $33,000 (1989) per patient per year in an
institution and with an average stay of three years until death, the cost of AD
will amount to $3 billion over the next three years; and if the entry into the
disease state remains constant, it will cost the Canadian taxpayer [an added]
$1 billion per year thereafter. (Brassard, 1993, p.11)
There have been many studies that conclude that the number of incidences of AD
is on the rise. A very high incidence was reported in a U.S. survey conducted
in East Boston by the Harvard Medical school. It showed the incidence of AD to
be 3% for people between the ages of 65-74, 18.7% for those between 75-84, and
47.2% for those over 84 (Evans, 1989, p.4).
AD is a democratic disease. It affects persons of both sexes and all races and
ethnic backgrounds. The major risk factors for AD are age and heredity. Persons
with a high incidence of AD in their family history are most susceptable.
A specific subtype of AD exists that is solely connected to heredity. This
subtype is known as Familial Alzheimer's disease (FAD). FAD is also known as
Early Onset Alzheimer's disease, named so because its symptoms start to develop
much earlier than in the regular sporadic type. Only 5%-10% of all cases are of
this type. FAD is suspected when AD can be traced over several generations and
there is a history of, among previously affected family members, a similar age
of onset and duration of the disease (usually 4 years). Approximately 50% of
the children of an affected parent go on to develop the disease (Pollen, 1993,
p.89).
Much research has been conducted in an attempt to locate the gene that is
responsible for FAD. Currently, researchers have isolated genes 1, 14, and 21
(Alzheimer's, 1996, p.36), however, the evidence still remains inconclusive
(Statement, 1996, p.2). There is also a possibility that a specific genetic
mutation merely puts a person at risk to the disease and AD is triggered by an
external force e.g. a head injury. (Statement, 1996, p.4). Finding the specific
location of the gene will pave the way for a diagnostic or even predictive test
for FAD. Similar genetic tests already exist for cystic fibrosis and muscular
dystrophy. Locating the AD gene will also allow scientists to study why the
particular gene is not functioning properly and may give clues to treatment and
cure. The long term goal of this research is the same as that of any other
genetic research and that is gene therapy - which is the possibility that
science could one day alter our genetic make-up.
The other much more common type of AD is Sporadic Alzheimer's Disease (SAD).
This includes all other types of the disease which are not linked to heredity.
Genetic research is also playing a major role in the progress towards a
diagnostic or predictive test for SAD. Recently, a gene involved in the
transport of cholesterol has been identified to be associated with AD.
Apolipoprotein E is located on chromosome 19 and seems to contribute to the
susceptibility of a person to AD (Statement, 1996, p.6). The gene exists in
three different forms or alleles (Apo E 2,3,4) and each person has a
combination of two of the three. Thus an individual can have any one of the
following combinations: Apo E 2/2, 3/3, 4/4, 2/3/, 3/4 or 2/4. Researchers have
found a relationship between the number of copies of the 4 allele and the
person's probability of developing the disease.