Research shows...

So, I'm curious. I have been wondering why there are so many more people today that have Alzheimer's. Or has it always been this bad and we simply called it senility before? 

• Senile by definition - showing a decline or deterioration of physical strength or mental functioning, especially short-term memory and alertness, as a result of old age or disease.
• Alzheimer's by definition - a common form of dementia of unknown cause, usually beginning in late middle age, characterized by memory lapses, confusion, emotional instability, and progressive loss of mental ability. (2) a degenerative disease of the central nervous system characterized by premature senile mental deterioration.
• Dementia by definition - severe impairment or loss of intellectual capacity and personality integration, due to the loss of or damage to neurons in the brain. (2) a condition of deteriorated mentality often with emotional apathy.

Research shows care will cost 200 billion dollars this year; that 1 out of 7 people with Alzheimer's live ALONE; that 5.4 million people are suffering from the disease; and, in my opinion, that we are a little confused on what to call it.  Try looking up the differences online, it WON'T clear the matter up...