Welcome - I did see this as well. The link: [urlhttp://www.cbs.com/shows/60_minutes/video/dRWD3hwiSX1mgZ_KUyERm9Fx8vUW_s42/over-a-barrel-90-/][/url]
(if I didn't post the link correctly, just got to www.cbs.com
and go to 60 minutes and you can watch clips or the whole item. I was a long segment.
This was a really long study started back in 1981 with 14,000 I believe they said. Interesting point, as Welcome said, that after autopsy, some with dementia or AD had no amyloid, and some without did have amyloid - plaques and tangles. No mention of APOE. At the end it was mentioned what they have seen is a series of mini-infarcts resulting in loss of communication between cortex and other parts of the brain. They did mention the PET scan used to look for amyloid.
But the question would be why do some progress and others do not. Diet? Genetics? Other takeaways: in older folk, low blood pressure bad, obese never good, underweight not good. But I didn't hear what the 'older' age was? 80 or 90 Plus?