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About dementia
Dementia is a group of symptoms. It’s caused by different diseases that damage the brain. The symptoms get worse over time and include:
- memory loss
- confusion and needing help with daily tasks
- problems with language and understanding
- changes in behaviour.
Dementia is progressive, which means symptoms may be relatively mild at first, but they get worse over time. There are many types of dementia but Alzheimer’s disease is the most common. The next most common is vascular dementia.
What causes dementia?
Dementia is not a natural part of aging. It is caused when a disease damages nerve cells in the brain.
Nerve cells carry messages between different parts of the brain, and to other parts of the body. As more nerve cells are damaged, the brain becomes less able to work properly.
Dementia can be caused by many different diseases. These diseases affect the brain in different ways, resulting in different types of dementia.
Types of dementia
Around 19 out of 20 people with dementia have one of four main types. Dementia affects everyone differently, however each type has some common early symptoms.
A person may also have mixed dementia where they have symptoms of more than one type.
Alzheimer’s disease
Alzheimer’s disease is the most common type of dementia. For most people, the first signs of Alzheimer’s are problems with their memory, thinking, language or perception.
