Overview, Causes, & Risk Factors
Dementia is not a disease. It is a group of symptoms
marked by gradual changes in brain function and the ability to think, reason, and
remember. Serious changes in memory, personality, and behavior
are the hallmarks of dementia.
What is going on in the body?
The ability of the brain to work correctly depends on a
complex communication system among billions of neurons, or brain cells.
Certain parts of the brain are in charge of creating a memory.
Others catalog this memory. Still others retrieve it. The way that a brain
functions could be compared to the workings of a computer.
If an area of the brain in charge of these special functions is
damaged, dementia may occur. Damage may be caused by infection,
loss of blood supply, chemicals, or a genetic tendency for losing neurons.
People normally lose a certain number of brain cells as they age.
However, major losses cause progressive and widespread loss of normal
In normal aging, memory loss
is usually slow. It may result in forgetting names, phone numbers, or where an
item was just placed. Intelligence and problem-solving skills are not affected.
True dementia involves loss of intelligence and problem-solving skills. It often
cannot be reversed and will become worse over time.
What are the causes and risks of the condition?
Dementia is always caused by an underlying disease or
condition. Brain tissue is damaged, and the ability to function decreases. Some
of these conditions can be reversed, while others cannot. The most common
cause of dementia is
In this disease, changes in nerve cells in some parts of the brain result in the death
of large numbers of cells. The result is a progressive, but slow, decline in memory and
Another common form of dementia is multi-infarct dementia. With this condition,
small strokes or changes in the blood supply to the brain from the narrowing
or hardening of arteries causes the death
of brain tissue. Symptoms will depend on what part of the brain tissue is
destroyed. These symptoms usually come on suddenly.
Other common causes are as follows:
a degenerative disorder of the nervous system that progresses quickly
and causes problems with walking, talking, and the senses. When dementia
occurs in young or middle-aged people, it is often due to this disease.
a progressive disease causing brain cells to waste away that affects both
the body and the mind. It causes changes in thinking, memory, speech, judgment,
and personality. Dementia often occurs in the later stages of the disease.
Huntingdon Disease has been linked to a certain gene that a person can inherit.
Lewy body disease, a degenerative disease of the nervous system. Lewy
bodies are deposits of protein in nerve cells, often deep within the brains of
those who also have Parkinson Disease. When these protein deposits
occur throughout the brain, dementia results. The course of illness is different
from Alzheimer's disease, in that it results in changes in the speed of thought,
memory, judgment, reasoning, and language. It can also cause a person to get
lost easily. In addition, it may cause hallucinations.
a degenerative disorder of part of the nervous system. Up to 30 to 40 percent
of people with this disease may develop dementia in the later stages.
also known as frontotemporal dementia, or FTD. FTD is a rare disorder of the
brain. It causes changes in personality, behavior, and memory over time. It
gets steadily worse, but it hard to diagnose until after death.
Other less common disorders that can cause dementia, or
dementia-like behaviors include:
chronic subdural hematoma,
a bleeding between the brain lining and brain tissue
that leads to AIDS
a disorder of the sheath that lines the brain and spinal cord
an infection of the nervous system by the
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which causes weakness and mental deterioration
normal pressure hydrocephalus,
which is a build up of cerebrospinal fluid in the brain. This condition can often be
treated through surgery to put a shunt tube in the brain that allows the excess fluid
to flow out of the brain.
progressive supranuclear palsy,
also known as Steele-Richardson-Olszewski syndrome, a rare disorder of
late middle age that causes widespread nervous system problems
viral or bacterial encephalitis,
a swelling of the brain
a rare disease causing an excess of copper in the liver, brain, kidneys,
Certain abnormal aspects of a person's metabolism or
hormones may also be responsible for the development of dementia,
including the following:
chronic alcohol abuse
chronic exposure to metals, such as lead
or mercury, and to dyes, such as aniline
high-dose steroid abuse
which means the thyroid gland is overactive
which means the thyroid gland is underactive
low body levels of B1 B2 B6 pantothenic acid folic acid niacin biotin
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too little niacin, which is vitamin B3
In some of these cases, dementia can be reversed by
removing the toxic agent or bringing vitamin levels back to a healthy range.
In older adults, depression and dementia are often mistaken for
each other. They do sometimes occur together, but depression is treatable,
while dementia is not.
Symptoms & Signs
What are the signs and symptoms of the condition?
Symptoms of dementia often aren't noticed right away. Or if they are, people
sometimes assume that dementia is just a part of
However, as more brain cells die, more brain functions
are lost, and symptoms become more severe. Common symptoms of dementia
include the following:
being disoriented to time and place
changes in mood, including depression
delusions, or believing things that are not true
hallucinations, which include hearing, seeing, feeling, and smelling things
that do not exist
impaired ability to orient the body to the surrounding space
language breakdown, with slurred speech and trouble finding the right words
loss of bowel and bladder control
a loss of interest in activities that gave pleasure before
memory loss that
affects the person's skills. Short-term memory, or memory of recent events, is
particularly affected in people with dementia.
personality changes, including agitation, irritability, paranoia, and hostility
poor or decreased judgment
trouble doing familiar activities
Sometimes, family members may not want to face how serious
their loved one's decline is. Doctors may misdiagnose the condition.
Diagnosis & Tests
How is the condition diagnosed?
Dementia can be diagnosed only if a doctor is made aware of the
problem. Diagnosis will start with a thorough physical and mental exam, as
well as the gathering of a detailed medical history. The family should be
prepared to tell the doctor the range of the person's
symptoms over time. The doctor will want to know how the symptoms
progressed and whether they have improved or become worse. Also, the family
should report how suddenly or gradually symptoms appeared.
A complete list of all medicines the person is taking will be
needed. This includes over-the-counter products,
and prescription medicines. Combinations of drugs may impair thinking
To determine if other medical conditions may contribute to the
symptoms, the doctor may order certain tests, such as:
blood tests, such as a complete blood count, called a
thyroid function tests,
tests for infectious diseases, and tests to determine vitamin levels in the
electroencephalogram, called an
which measures brain waves
electrocardiogram, called an EKG,
which measures the electrical activity of the heart
cranial MRI or
cranial CT scans,
which can be used to view the structures of the brain
spinal tap, a
procedure in which a small amount of fluid is withdrawn from the spinal column
to check for infection or bleeding
Since there is no definitive test for dementia in a living person,
the doctor will try to rule out other conditions or diseases that may
cause the symptoms.
Prevention & Expectations
What can be done to prevent the condition?
Most cases of dementia are caused by
Although there are no proven methods to prevent Alzheimer's disease,
recent research findings provide some options that may slow the onset of the
disease or how fast symptoms progress. These findings, which need further
study, include the following:
low doses of aspirin and nonsteroidal anti-inflammatory drugs, called
NSAIDs, which may work by making blood cells and vessels less sticky
and by improving blood flow
actively engaging in cognitive activities such as reading, which may
increase the nerve connections in the brain and delay the onset of the
taking antioxidants such as vitamin E
and selignine. In the Alzheimer Disease Cooperative Study, a
dose of 1,000 IU of vitamin E and 5 mg of selignine twice daily delayed nursing
home placement, loss of the ability to perform self-care, and severe
hormone replacement therapy
women, which may delay the onset of symptoms of Alzheimer disease.
The relationship between the hormone estrogen and Alzheimer disease
needs further study.
avoiding head injuries. A person should wear a seat belt at all times when
riding in a motor vehicle. Sports safety guidelines for
can be helpful in avoiding other head injuries.
Strokes are another major cause of dementia. Preventing or
treating high blood pressure,
and alcohol abuse
can lower the risk of stroke.
What are the long-term effects of the condition?
Long-term progressive dementia results in the continued
loss of mental abilities. In the end, the person is unable to care for him or
herself. A person suffering from the condition often requires nursing
home care. Falls, trauma, infections, and
may also result in a need for more intense medical care.
What are the risks to others?
Dementia poses no risk to others, except for the disruption
to home life and family relationships.
Treatment & Monitoring
What are the treatments for the condition?
Even when dementia is incurable, there are things that can be
done to treat the patient and help his or her family to cope. Medical care
is crucial, both for the patient and to answer questions family may have.
In the early and middle stages of Alzheimer disease, medicine
may help. The three medicines currently approved by the Food and
Drug Administration for treatment of Alzheimer disease are donepezil,
tacrine, and rivastigmine. These medicines are designed to improve
memory by increasing the amount of acetylcholine in the body.
Other medicines, such as risperidone or quetiapine, may
also be used to help behavioral problems such as hallucinations,
delusions, or agitation. Some people with dementia may also need
medicines for depression,
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Eating a healthy diet and practicing healthy lifestyle habits
can also help any person to maintain health status. In addition, the person's
caregivers should work to maintain a daily routine, help the person to be
as active as possible, and maintain social contacts. Memory aids such as
posting big calendars, making lists of daily plans, and hanging up written
directions for household tasks can help greatly.
Other treatments include support and education for those caring
for people with dementia. Individual and family counseling can help. Support
groups have also been found to assist caregivers. As the disease progresses,
many families are unable to provide home care for the person with dementia,
and placement in a special facility is needed.
What are the side effects of the treatments?
Medicines used to treat dementia can damage the liver,
so periodic liver function tests
are needed. Other side effects may include:
What happens after treatment for the condition?
In most cases, dementia is a progressive disease without a
cure. Treatment is lifelong. Because the course of dementia is hard to predict,
people with the condition should make plans for end-of-life care while
they are still able to think clearly.
Some of the challenges that family members
may face include:
promoting independence while making sure the person is safe
stopping the person from driving
finding supportive care among family, in an assisted living facility,
or in a nursing home
making business decisions
determining executors of written wills and making sure that advanced
directives are in the person's patient file at his or her doctor's office
How is the condition monitored?
A person with dementia needs to have regular visits to the doctor
for evaluation and treatment. From time to time,
liver function tests
may be ordered if the person is taking one of the medicines that can cause
liver damage. Any new or worsening symptoms should be reported to the doctor.