Some Notes From a Lecture on Memory Loss

5.4 million Americans have Alzheimer's.

500,000 people in their '30s, '40s and '50s have it or a related dementia.

Every 69 seconds someone in America develops Alzheimer's. 

Alzheimer's is the most common type of dementia and accounts for 70 per cent of cases. 

70 per cent of people with Alzheimer's live at home where family and friends provide most of their care and pay for it out of their own pockets.

I would add that the above information comes from the Alzheimer's Association which has something of an interest in obtaining money for their programs and  funding.
alz.org