Some lesser known signs of Alzheimer's

Behavioural change - can be a sign of Frontotemperal Dementia (a form of dementia that often affects adults aged 45-65).  Affecting the ability to discern right from wrong usually involving stealing or other law breaking activity that is out of character.

Frequent falling - researchers scanned the brains of individuals who were prone to tripping and falling and noticed a correlation with frequent falling and the early onset of Alzheimer's. 

A change in eating patterns - eating more frequently and often inappropriate things including paper and flowers can be indicators of the onset of Alzheimer's, this may be because the brain is receiving hunger signals but can't discern how to react to them. 

A sudden inability to recognise sarcasm - this is often as the brain's posterior hippocampus is affected where short term memory is stored and where the brain interprets sarcasm. 

Depression - if an individual has never suffered from clinical depression before the age of 50.  A diagnosis of depression in later life does not automatically mean an individual will develop Alzheimer's but may raise the possibility.  Scientists believe that hormones released into the depressed brain may damage certain areas of it, leading to the development of Alzheimer's or other forms of dementia.