People with a gene variant called APOE4 have a higher risk of developing Alzheimer's disease. However, keeping your brain busy may delay some of the signs of Alzheimer's disease. 

A person with a learning disability is more likely to develop dementia, and it may get worse quicker than someone without a learning disability. However, for people with more complex learning disabilities, the initial symptoms are likely to be less obvious.

Getting an accurate diagnosis is important but can take longer for a younger person. Read more about being referred to a specialist and genetic testing. 

Taken from one of our 2012 magazine issues, find out why inherited forms of Alzheimer's disease are extremely rare, but for a small proportion of families who carry particular genes the results can be devastating.