We're a nation living longer and longer. Over the next 30 years, the number of Americans age 90 and above is expected to triple, and an NIH-funded research study called 90+ at the University of California Irvine is trying to learn all it can right now from a group of men and women who've already managed to get there.
Six years ago, we first reported on their first set of findings.
Factors associated with longer life: exercise, moderate drinking of alcohol and caffeine, social engagement, and our favorite: putting on a few pounds as we age. The 90+ study's focus is now on memory and dementia. What they've learned -- and what they haven't -- drew us back, as did the 90+ers. Take a quick look at when we first met them in 2014.
Ted Rosenbaum: My birthday is February 7th, 1918.
Lou Tirado: I was born on August 25th, 1920, and I'm 93+.
Ruthy Stahl: June 15, 1918, and it was, I'm sure, a lovely day. (LAUGH)
The men and women we met 6 years ago had all agreed to be checked out by the 90+ Study team, top to bottom, every six months -- their facial muscles, how they walk, how fast they can stand up and sit down and, critically, how they think.
TESTER: Now spell world backwards.
Jane Whistler: D-L-R-O-W
They were an impressive and active group -- a B-17 gunner in World War II, a fellow World War II vet who drove a convertible, a 95-year-old speed walker, ballroom dancers.
Henry Tornell: I asked them, "Aren't you gonna ask us any questions about our sex life?" And they said no.
Helen Weil: (LAUGHTER)
And sadly, some who had begun to struggle with dementia.
TESTER: What is today's date?
Ted Rosenbaum: Today's date?
Ted Rosenbaum: Today's date?
Lesley Stahl: What's the oldest person you have seen?
Dr. Claudia Kawas: I have seen several 116-year-olds.
Neurologist Claudia Kawas, the 90+ Study's lead investigator, says studying the oldest old is increasingly important.
Dr. Claudia Kawas: Half of all children born today in the United States and Europe is going to reach their 103rd or 104th birthday.
Lesley Stahl: Half?
Dr. Claudia Kawas: Yes.
Lesley Stahl: Half the children born today are gonna live to 100?
Dr. Claudia Kawas: To 103 or 104.
Helen Weil: You know, I don't feel a day older than I was yesterday.
They invited us back 6 years later, and we found some study participants like Helen Weil, the ballroom dancer, thriving.
Now 99, Helen showed us how she exercises in her chair.
Lou Tirado, the World War II gunner, turned 100 in August. Lou is using zoom. When he was a kid, most homes didn't have a radio.
Lesley Stahl: Do you have an iPhone?
Lou Tirado: I have an iPhone.
Lesley Stahl: Are you on Facebook?
Lou Tirado: Yes.
Lesley Stahl: Do you use Siri?
Helen Weil: Yeah, I tell her every evening, "Wake me up at 6:30 tomorrow morning."
Lesley Stahl: And she does?
Helen Weil: Yeah. Yes. (LAUGH)
TESTER: Who is our current president?
Lou Tirado: President is Trump.
TESTER: Who was the president before Trump?
Lou Tirado: Obama
Because of COVID-19, the 90+ Study is doing cognitive tests by phone.
TESTER: Subtract 7 from 100.
Lou and Helen aced them.
TESTER: And keep subtracting 7.
Helen Weil: 93, 86, 79..
Dr. Claudia Kawas: Her memory is better than mine. (LAUGH)
But one of our favorite 90+er's from six years ago, Ruthy Stahl, is not so lucky. Back then, at 95, she was zipping around in her lime green bug, but today, at 102, she didn't remember our having met.
Ruthy Stahl: And what is your first name?
Lesley Stahl: Lesley.
Ruthy Stahl: That's a nice name.
Lesley Stahl: Thank you.
Ruthy is as charming and upbeat as ever, but her memory is failing.
TESTER: The current president, or the president before him, I'll take either.
Ruthy: No, I can't.
Lesley Stahl: Do you remember your parents?
Ruthy Stahl: No.
Lesley Stahl: No? Oh, my.
Ruthy Stahl: That's funny I don't remember them.
Lesley Stahl: Is it frustrating when you can't remember?
Ruthy Stahl: No.
Lesley Stahl: No?
Ruthy Stahl: It just passes on to something else. (LAUGHTER)
Dr. Kawas says most people, probably even most doctors, would assume Ruthy's memory problems stem from Alzheimer's disease. But scientists are finding out more and more about the complexities of what causes dementia.
Lesley Stahl: You hear people say, "She got Alzheimer's. He has Alzheimer's," when they really should say dementia.
Dr. Claudia Kawas: That's exactly right. Dementia is a loss of thinking abilities that affects your memory, your language. It's a syndrome. It's a syndrome kind of like headache is a syndrome. You can have a headache because you've got a brain tumor or you can have one because you drank too much, and it's the same with dementia.
We were sad to learn that some of the 90+ participants we met in 2014 have passed away, but by donating their brains, as Ted Rosenbaum did, they are very much still part of the study, contributing some of its most fascinating, and confounding, results.
After a participant dies, the 90+ team gathers to review mounds of data. Now, because of COVID, they gather on zoom.
Ted's test results showed years of memory problems, as we had seen six years ago. The 90+ team concluded that Ted probably had Alzheimer's disease, but then awaited results from their collaborators, a team of pathologists at Stanford University, who independently examined Ted's brain.
Dr. Claudia Kawas: They don't know anything except the brain they've got in front of them.
Lesley Stahl: And then you come together.
Dr. Claudia Kawas: And then we come together and it's like a reveal party.
The definition of Alzheimer's disease is having the proteins amyloid and tau, often called plaques and tangles, in the brain.
But when the Stanford team made their report, Ted's brain didn't have either.
Doctor: As you may see without even zooming in, the section is clear, it's clean. We're negative for beta amyloid here.
Claudia: It actually looks awfully good.
Doctor: It actually does, yes.
Lesley Stahl: You sit around, you look at that--what do you conclude?
Dr. Claudia Kawas: The only pathology we found in his head actually was TDP-43.
TDP-43. A breakthrough. It's a newly identified cause of dementia, a protein originally found in ALS patients that Kawas now believes accounts for up to one in five cases of dementia in people over 90.
Lesley Stahl: Can you find out if you have TDP-43 while you're alive?
Dr. Claudia Kawas: Not yet.
And you can't find out if you have two other dementia-causing conditions either -- tiny strokes called microinfarcts that damage brain tissue, and hippocampal sclerosis -- a shrinking and scarring of part of the brain. So it's likely that many people in their 90's who are diagnosed with Alzheimer's may actually have something else.
Dr. Claudia Kawas: There's a whole lot of stuff that goes on in the brain, that we have no way of diagnosing during life. So, we get a lot of those surprises, but we also get surprises where people have an awful lot of pathology in their brain, a lot of Alzheimer's disease, a lot of TDP disease. And they still turn out to be normal.
Henry Tornell: Let me hold the chair for you.
That's what happened with Henry Tornell, Helen Weil's ballroom dancing partner who joked about studying sex over 90. Henry died at 100 of cancer -- mentally sharp as ever.
But his brain told a different story.
Doctor: Beta amyloid, I don't even have to zoom in. Florid. Very positive. Positive as well.
The Stanford team found the highest level of plaques and tangles -- and TDP-43. Especially stunning, since more than one pathology typically means more severe dementia.
Lesley Stahl: So he was a huge surprise.
Dr. Claudia Kawas: He was one of our surprising 90-year-olds who managed to have good cognition in the face of things in their brain that should cause dementia.
It used to be that when a person like Henry with clear thinking was found to have plaques and tangles, scientists assumed dementia was just a matter of time. But now they're thinking about it in a new way -- that maybe certain people have protection against dementia, a phenomenon they're calling "resilience." To prove it, though, they need to follow people who are still alive. Enter convertible-driving Sid Shero from our story in 2014.
Sid had a PET scan back then for the study, which revealed significant amounts of amyloid in his brain. The question was, would dementia be around the corner, or might sid somehow be "resilient?"
Sid turned 99 this summer.
Lesley Stahl: How old do you feel?
Sid Shero: I always say 69.
Sid has circulation problems that affect his breathing, but his memory? Well, he told us about buying his first car 80 years ago, for $18, in a pool hall.
Sid Shero: A '31 Chevy convertible with a rumble seat.
Lesley Stahl: A rumble seat!
Sid Shero: And I didn't know how to drive.
Lesley Stahl: You won it in a pool hall. Did you win it on a bet--
Sid Shero: I didn't win it. I bought it--
Lesley Stahl: You bought it?
Sid Shero: I gave him $18.
Lesley Stahl: Who sold a car for $18?
Sid Shero: He needed the money to shoot pool.
Dr. Claudia Kawas: So I know he's got at least two pathologies in his head. I know he's got, you know, probably high amounts of Alzheimer's, and I know he's got some vascular disease. And we tested him just a couple of weeks ago and he did great.
TESTER: Please tell me how many nickels in a dollar?
Sid Shero: 20.
TESTER: How many quarters in six dollars and 75 cents?
Sid Shero: 27.
TESTER: Wow, you are quick!
Lesley Stahl: So is that resilience?
Dr. Claudia Kawas: I think that is definitely resilience. Sid might be what resilience is all about.
Lesley Stahl: Could it be a gene?
Dr. Claudia Kawas: It absolutely could be. Or maybe even more likely, multiple genes or combinations of genes.
Lesley Stahl: Here's my observation.
Dr. Claudia Kawas: Okay.
Lesley Stahl: You knew more six years ago than you do now. There are just so many questions that we don't know the answers to-- more questions.
Dr. Claudia Kawas: That is really a brilliant observation.
And what science is all about. For every new answer, two new questions. For every new discovery, like TDP-43 dementia, and especially resilience, new mysteries to solve. So like its participants, the 90+ Study is keeping at it, trying to help the rest of us make it to age 102 with Ruthy's spirit, but memory intact.
Ruthy Stahl: It's a shame.
Lesley Stahl: It's a shame.
Ruthy Stahl: 'Cause there's a lot I could remember.
Lesley Stahl: And-- I'll bet you had a wonderful life.
Ruthy Stahl: Oh, I have. It's still going on. Thank goodness.
Produced by Shari Finkelstein. Associate producer, Braden Cleveland Bergan. Field producer, Jennie Held. Broadcast associate, Wren Woodson. Edited by Sean Kelly.
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