People with later-stage dementia will eventually need full-time care and support with daily living and personal care, such as eating, washing and dressing. Whatever kind of dementia a person has, their life expectancy is on average lower.

In the middle stage of dementia, symptoms become more noticeable and the person will need more support in managing daily life. This stage of dementia is often the longest. On average it lasts about two to four years.

Knowing how different types of dementia affect the brain helps explain why someone with dementia might behave in a certain way.