Dementia is a term used to describe various different brain disorders that have in common a loss of brain function that is usually progressive and eventually severe. There are over 100 different types of dementia. The most common are Alzheimer’s disease, vascular dementia and dementia with Lewy bodies.
What's the difference between Dementia and Alzheimer's?
In a nutshell, dementia is a syndrome, and Alzheimer's is the cause of the symptom. When someone is told they have dementia, it means they have significant memory problems as well as other cognitive difficulties, and, these problems are severe enough to get in the way of daily living. Most of the time dementia is caused by Alzheimer's disease.
Contrary to what some people may think, dementia is not a less severe problem, with Alzheimer's disease being a more severe problem.
Symptoms of dementia include loss of memory, confusion and problems with speech and understanding. Dementia is caused by the damage of brain cells. A head injury, stroke, brain tumor or disease (such as Alzheimer's disease) can damage brain cells.
The onset of Alzheimer’s disease is often difficult to pinpoint, as it starts with forgetfulness and difficulty in finding the right word, which are, of course, common problems associated with ageing. Most people with dementia are older, but it is important to remember that most older people do not get dementia. It is not a normal part of ageing. Dementia can happen to anybody, but it is more common after the age of 65 years. People in their 40’s and 50’s can also have dementia.
When the brain is functioning normally, it exchanges signals from other parts of the body, and other parts of the brain, across the gaps (synapses) between nerve cells. These signals – in the form of countless electrical impulses – are essential for brain activity such as language and problem solving. They are also involved in controlling motor functions, such as instructing muscles when and how to work.
Alzheimer’s disease is the result of the destruction of nerve cells (neurons) in the brain. These nerve cells cannot be replaced, so a person with Alzheimer’s disease gets progressively worse as more cells are destroyed.
People who have dementia have a problem in the brain that makes it hard for them to remember, learn and communicate. These changes eventually make it hard for them to care for themselves. Dementia may also cause changes in mood and personality. Early on, lapses in memory and clear thinking may bother the person with dementia. Later, disruptive behavior and other problems can create a burden for caregivers and other family members.
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Symptoms
As the disease progresses, memory loss, difficulty in completing simple tasks, and more overt personality changes, often combined with depression, become more evident. Mathematical and verbal skills decline, which mean that a person may no longer be able to read instructions or to count their change. Conversation can become empty and meaningless.
In these early stages, the people closest to the person with Alzheimer’s disease may notice personality changes. For example, a previously cheerful person may become irritable and even aggressive. He or she may no longer be able to cope with the demands of a busy life.
Sometimes people with Alzheimer’s may become paranoid believing, for example, that their carers are trying to harm or kill them or that their partner is being unfaithful. People with Alzheimer’s can also lose their sense of time and place – they may, for example, get dressed in the middle of night or wander off and get lost, even in once-familiar territory.
This can cause a great deal of stress and upset for the person’s carers and family who have, in effect, lost the person they once knew.
During the late stages of the disease, people with Alzheimer’s may become totally dependent on others for their care. Walking can become difficult, and he or she may be confined to bed. They may become incontinent, experience hallucinations and become increasingly unaware of their surroundings. It is at this stage that residential care, with round-the-clock nursing, is often considered.
The disease lasts on average about ten years, though the period of time between diagnosis and the person dying varies from three to 20 years. Often the cause of death in a person with Alzheimer’s is another illness, such as pneumonia, which becomes more common in people who are bed-bound and therefore less resistant to infection.
What causes Alzheimer’s?
Nerve signals travel across the synapses with the help of chemicals known as "neurotransmitters", including one called acetylcholine. Doctors believe that nerve cell destruction causes a reduction in acetylcholine, leading to impaired transmission of nerve signals.
Other explanations of Alzheimer’s disease focus on areas of abnormal protein in the brain called "plaques" and "tangles", the names reflecting what these abnormalities in the brain look like under the microscope.
The underlying cause of Alzheimer's – what actually triggers the changes in the brain – is still not known. It is likely that no single factor is responsible, but rather that it is due to a variety of factors, which may differ from person to person. People whose parents or brothers and sisters develop the disease appear to be at greater risk of developing it themselves, so there may be a genetic component. However, no straightforward pattern of inheritance has been found.
It is known that head injury is a risk factor, and also that Alzheimer’s disease often affects people with Down’s syndrome.
Some researchers have suggested that people who exercise their brains (for example, doing crosswords and other mental agility exercises) are less likely to develop the disease. And Omega 3 fatty acids, contained in oily fish such as mackerel and salmon may, also help to prevent dementia. But there is no completely solid evidence to show how environmental factors influence the chance of getting Alzheimer’s.
How is dementia treated?
Some causes of dementia can be treated. However, once brain cells have been destroyed, they cannot be replaced. Treatment may slow or stop the loss of more brain cells. When the cause of dementia can't be treated, the focus of care is on helping the person with his or her daily activities and reducing upsetting symptoms. Some medicines can help people with dementia. Your family doctor will talk with you about treatment options.
Why do people with dementia become agitated?
The agitation can have many causes. A sudden change in surroundings or frustrating situations can cause people who have dementia to become agitated. For example, if he or she can't get dressed without help or gives the wrong answer to a question it may cause frustration. Being challenged about his or her confusion or inability to do things may also make the person agitated. As a result, the person may cry, become irritable, or try to hurt others in some way.
How can I deal with agitation?
One of the most important things you can do is avoid situations in which your loved one might become frustrated because he or she fails to remember something or forgets to do something. Try to make your loved one's tasks less difficult. For example, instead of expecting him or her to get dressed alone, you can just have your loved one put on one thing, such as a jacket, on his or her own.
You can also try to limit the number of difficult situations your loved one must face. For example, if taking a bath or shower causes problems, have him or her take one every other day instead of every day. Also, you can schedule difficult activities for a time of day when your loved one tends to be less agitated. It's helpful to give frequent reassurance and avoid contradicting him or her.
What should I do if hallucinations are a problem?
If the hallucinations are not making your loved one scared or anxious, you don't need to do anything. It's better not to confront people about their hallucinations, because you will not be able to convince them that there are no voices or people. Arguing may just upset your loved one. If the hallucinations are scary to your loved one, you can try to distract the person by involving him or her in a pleasant activity.
What if my loved one will not go to sleep at night?
First, try to make the person more aware of what time of day it is. Place clocks where he or she can see them. You can also keep curtains or blinds open so that he or she can tell when it is daytime and when it is nighttime.
Limit the amount of caffeine he or she consumes. Try to help your loved one get some exercise every day. Don't let him or her take too many naps during the day. Be certain that the bedroom is peaceful, since it is easier to sleep in a quiet room. At night, provide a night light or leave a dim light on, because total darkness can add to confusion. If your loved one has arthritis or another painful condition that interrupts his or her sleep, ask your doctor if it is okay to give your loved one a medicine for pain right before bed.
What if wandering becomes a problem?
Sometimes very simple things can help with this problem. It is all right for your loved one to wander in a safe place, such as in a fenced yard. By providing such a safe place, you may avoid a confrontation. If this doesn't work, remind your loved one not to go out a certain door by placing a stop sign on it or putting a piece of furniture in front of it. A ribbon tied across a door can serve as a similar reminder. Hiding the doorknob by placing a strip of cloth over it may also be helpful.
An alarm system will alert you that your loved one is trying to leave a certain area. Your alarm system may just be a few empty cans tied to a string on the doorknob. You might have to place special locks on the doors, but be aware that such locks might be dangerous if a house fire occurs. Don't use this method if your loved one will be left home alone. Make sure your loved one wears a medical bracelet, in case they do wander away from home.