What are the symptoms?
The symptoms of all types of dementia are similar. They can be divided into three main areas:
Loss of mental ability
Memory problems are usually the most obvious symptom in people with dementia. Forgetfulness is common. As a rule, the most recent events are the first forgotten. For example, a person with early stages of dementia might go to the shops and then cannot remember what they wanted. It is also common to misplace objects. However, events of the past are often remembered well until the dementia is severe. Many people with dementia can talk about their childhood and early life. As dementia progresses, sometimes memory loss for recent events is severe and the person may appear to be living in the past. They may think of themself as young and not recognise their true age.
Someone with dementia may not know common facts when questioned (such as the name of the Prime Minister). They may have difficulty remembering names or finding words. They may appear to be asking questions all the time.
Language problems can also develop. For example, someone with dementia may have difficulty understanding what is said to them or understanding written information. Problems with attention and concentration can also occur. It is common for someone with dementia not to be able to settle to anything and this can make them appear restless.
New surroundings and new people may confuse a person with dementia: they can become easily disorientated. However, in familiar places, and with old routines, they may function well. This is why some people with mild dementia cope well in their own homes. Losing track of time is also a common problem in someone with dementia. For example, not knowing if it is morning or afternoon, or what day it is. A person with dementia may get lost easily.
Even clever people who develop dementia find it difficult to grasp new ideas or learn new skills. For example, how to use a new household gadget. The ability to think, calculate and problem-solve can be affected as intellect begins to fail. Difficulties with planning and decision making can develop.
Changes in mood, behaviour and personality
At first, someone with dementia may appear to be easily irritated or moody. It is often family or friends who notice this. Some people with early dementia recognise that they are failing and become depressed. However, many people with dementia are not aware that they have it. They may remain cheerful. The distress is often felt more by relatives who may find it difficult to cope.
More challenging behaviour may develop in some people over time. For example, in some cases, a person with dementia may become quite disinhibited. This means that he or she may say or do things quite out of character. This is often difficult for families and friends to cope with. Some people with dementia can also become agitated or even aggressive and this may be directed towards their carers. They may become suspicious or fearful of others. In some people, delusions (abnormal beliefs) and hallucinations (a false perception of something that is not really there) can occur. Visual hallucinations can be a common problem in dementia with Lewy bodies (DLB).
Mood, behaviour and personality changes may mean that someone with dementia is not able to interact with others in a social situation and they can become quite withdrawn. Sleep is often affected and pacing and restless wandering can become a problem for some.
Problems carrying out day-to-day activities
Difficulty with self-care usually develops over time. For example, without help, some people with dementia may not pay much attention to personal hygiene. They may forget to wash or change their clothes. Remembering to take medication can become an issue. The person may also have difficulty keeping up their home. Shopping, cooking and eating may become difficult. This can lead to weight loss. Driving may be dangerous and not possible for someone with dementia.
How does dementia progress?
The speed in which dementia progresses varies greatly from person to person. It can also depend on the type of dementia that someone has. Typically, symptoms of dementia tend to develop slowly, often over several years. In the early stages of the disease, many people with mild dementia cope with just a small amount of support and care. As the disease progresses more care is usually needed.
In the later stages of dementia, speech may be lost and severe physical problems may develop, including problems with mobility, incontinence and general frailty. This can make people more susceptible to other health problems such as infections. Often, people with dementia die from another health problem such as a severe chest infection. So, the dementia isn't the cause of their death but has contributed to it.
Some people can live for many years after dementia has been diagnosed. However, the condition does shorten lifespan. On average, once diagnosed with dementia, people are:
- In the mild early stage for one or two years.
- In the moderate stage, needing help looking after themselves for another two or three years.
- In a severe stage by four to five years after diagnosis, being completely dependent on carers and more or less completely inactive.
The average survival after diagnosis is 3-9 years, but people can survive for up to 20 years after being diagnosed with dementia.
Did you find this information useful?
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