I’m William Brangham, and this is "Horizons."

Everyone wants to keep a sharp mind as they age, especially as dementia cases continue to rise across the U.S.

Now, a growing body of evidence suggests almost half of the key risks for cognitive decline can be prevented or delayed.

From lifestyle to your environment, we explore the emerging science that can help protect against dementia, coming up next.

♪ Announcer: Support for "Horizons" has been provided by... Steve and Marilyn Kerman and the Gordon and Betty Moore Foundation.

Additional support is provided by Friends of the NewsHour.

♪ This program was made possible by contributions to your PBS station from viewers like you.

Thank you.

From the David M. Rubenstein Studio at WETA in Washington, here is William Brangham.

Welcome to "Horizons."

We’re talking again this week about dementia.

On our last show, writer Bob Kolker told us about the family at the heart of his new book, "The Vanishing Family," which is a heartbreaking story of people with a specific genetic mutation that, if you have it, all but guarantees you’ll suffer from a rare type of dementia that strikes very early in life.

But this week, we want to talk about some better news about this grim condition, one that currently affects an estimated 57 million people worldwide.

That good news is that there is an emerging body of evidence that there are certain risk factors that make it more likely that a person will develop dementia.

And while not being a cure, targeting those risk factors can slow or even help prevent the onset of dementia.

Here to talk about this is Dr.

Jonathan Rosand.

He’s the former chief of neurocritical care at Mass General Brigham, a professor of neurology at Harvard, and the founder of the Global Brain Care Coalition.

Jonathan, so nice to have you on the program.

Thank you for being here.

It’s a real pleasure to be here.

You know this very well, but there is certainly a level of fatalism out there in the world when it comes to dementia and Alzheimer’s.

People think you either get it or you don’t get it.

And the idea that you have some agency in that or that there are things that you can do to change that binary comes as just a surprise.

So tell us what we have learned.

Well, it is remarkable how that fatalism persists when we’ve learned so much.

But over the last decade, it’s become quite clear that roughly 40 to 45% of all dementias, and that includes Alzheimer’s, are what we call attributable to risk factors that we can modify, things we do every day, behaviors we do every day.

And related and making these figures even more important for us is that about 75 to 80% of all strokes could be potentially prevented or delayed, and at least 35% of depression.

So the evidence has accumulated over decades, and scientists all over this country and the world have contributed to this data.

But it’s now very clear that every day we have an opportunity to make decisions and make changes or keep doing what we’re doing to make sure that we reduce our risk as much as we can.

So nice that there’s actually some good news, especially about a topic that I think people just think there’s just a very grim cloud over this entire topic.

What are those things?

Like walk us through some of the specifics that people can do.

Rosand: So at the Global Brain Care Coalition, what we’ve done is we’ve scoured all of the science, and we’ve identified the 12 items for which the evidence is kind of rock solid.

And what that means is that you’re not going to see a study in the future that debunks one of these, and that was important to us.

We really wanted to get to the sort of ground truth.

And those 12 items, and we’ve created a score called the Brain Care Score around these items.

Those 12 items include the physical like blood pressure, blood lipids or cholesterol, blood sugar or hemoglobin A1C, diabetes related.

They include diet, exercise, physical activity, sleep, alcohol consumption, cigarettes, BMI.

And then crucially, they also include social components.

So our social relationships, whether we have meaning or purpose in life, and the degree to which we manage the stress in our lives.

And so this Brain Care Score that we and our colleagues have created serves as a reminder and also as a measure of those behaviors.

So you can track how well you’re doing at reducing your risk.

I know you’ve created this questionnaire that allows people to go through this and to say, "This is how much I smoke, this is how much I drink."

But on this point about the clarity of the science on this, how do we know those things?

How has the scientific community come to the understanding that if your BMI is X, it ups your risk?

If your blood sugars are Y, it ups your risk.

How do we know those things?

Well, there are two types of studies in general that we look to.

One is what’s called an observational study, where you characterize large numbers of people, you measure different aspects of their behavior, of their BMI, their blood pressure, things like that.

And then you follow them over the years to see what conditions they develop.

So those are association studies.

But the real science to determine whether you change something and then you lower your risk, those require what we call clinical trials, where an intervention is assigned to one group or another.

So what the basis of all this science is still is these observational studies.

There are more and more exciting clinical trials that your viewers probably have heard of that have shown that lifestyle change has an impact on your cognitive decline rate, dementia, things like that.

Blood pressure has an impact on all these things.

If you lower it, you see a change in your risk.

And there are more and more of these kinds of studies coming out.

But we have concluded, and we’re not alone, we are working with colleagues around the world on this, that the association studies are sufficient.

That is... Brangham: That feels robust enough.

Absolutely.

We are comfortable saying that because, in addition, these risk factors are shared by so many other conditions.

The downside of modifying them is minimal to zero.

Except that it requires behavioral change, which, I’m not telling you anything you don’t know, that is a tough nut to crack.

Rosand: Yes.

So we’re working with colleagues all over to crack that nut.

And there has certainly been fatalism in the field of behavior change.

And not without... Brangham: Meaning that people in your profession think, "We’ve tried this "and we can’t quite nudge that needle."

Rosand: Yeah.

- Really.

I can’t tell you how many of my physician colleagues have said, you know, "I’ve tried, I’ve devoted my career "to getting patients to exercise or lose weight.

"I don’t know how you do it."

And I understand.

My answer is, we haven’t figured out exactly how to help folks.

And that’s the challenge we face.

And so this score is our first venture into this space.

And one of the secrets to the score is that we worked on it with patients.

It is the product of what we would call co-creation.

So we went through lots of trials and errors in developing this score because our patients told us what they thought worked and what didn’t work.

We were in search of something that would be authoritative.

So for example, if a grandparent were to come home for Thanksgiving dinner with their granddaughter in medical school and showed them this score, the brain care score that they’d gotten from their doctor, the last thing we wanted the up and coming bright, ambitious granddaughter medical student to say is, "Well, you know, that’s not proven, "you know, I’ve just learned that, you know, "that’s not proven through this trial or that trial."

We wanted the granddaughter to respond by saying, "Oh, yeah, everybody knows that."

We wanted to first lay out what the rock solid science was.

And then we wanted to create something that people could feel like they could use.

And so the secret to the brain care score is that we’ve created a rubric where you can raise your score through however you choose to start.

So one of my favorite recurrent stories, I’ll have a patient come to see me who will say, "You know, doctor, "my parents both have Alzheimer’s.

"My grandparents had Alzheimer’s.

"I know I need to lose weight.

"If all you’re going to do is tell me I need to lose weight, "I may as well just walk out now, "because I can’t lose weight."

So that’s a signal to me about what not to talk about in that setting.

The brain care score offers someone like that so many other places to start.

And I can’t tell you how satisfying it is for somebody who started off my, you know, the first visit that way, comes back to tell me, "You know, "now that I’ve gotten better with my blood pressure, "now that my sleep has changed, "I’m ready to talk about working on my weight."

Brangham: So interesting.

- So it’s really a way of understanding there’s so many paths to reducing risk.

Each of us just has to figure out the path that will work for us.

Do you think part of it is also that that conversation is happening when someone is already sort of downstream or well into middle life, they’re heavy, that these are the conversations that should have happened a long time ago, well before they’re sitting in what is an admittedly pressured environment of meeting with their doctor?

Yes, but, you know, there... Brangham: You take it where you can get it.

I think that’s right.

I think we were so good, understandably so, at identifying the failures of our health care system, and I could go on forever.

Right, we did a whole episode about basically the decimation of the primary care system.

No one is getting reimbursed for prevention, and so that basically gets shunted aside.

So when it comes to dementia and preventing dementia, we have seen that the motivation for that is special, because anybody who has lived through watching someone they care about with dementia, it’s one of the most heart-rending, awful experiences.

It’s an experience of powerlessness.

It’s an experience of watching somebody you care about lose their dignity.

We believe that if those individuals who have been so affected can be offered something hopeful to do, that it will be more likely to stick.

And our job as the community that’s come together in this coalition, our job is to help folks get the information that they ultimately will be able to use for themselves.

And primary care can help, absolutely.

Primary care is our bedrock, but we can’t wait for us to fix primary care, right?

We’ve got to take care of ourselves.

We’ve got to move now.

Can we loop back a little bit to some of those practicalities?

You mentioned just passing smoking, hypertension, alcohol.

If people wanted to start to chip away at their score, walk me through some interventions.

What are the things that if you had to say to someone, "Look, I know we’ve got this suite "of possible interventions "that you could take in your own life, "target a couple of these, maybe pick this, pick that."

What are some of the things that people can do?

Well, what we do in the office is we get to know each other.

And so my job is to help a patient figure out where they’d like to start.

And once we figured out where you would like to start, that’s where we start.

For many people... Is that the lowest hanging fruit for them or where their motivation comes from, both?

I think it’s a combination of those things.

It’s also, they may have a partner or a spouse who loves to cook.

They may have a partner or a spouse who’s got an exercise regime.

They may have a friend who has recommended a jogging route or something.

So what I’m alluding to is the social, you want to figure out what the social relationships are.

They may have been an athlete when they were younger and just never found the time to do it.

One of our hacks, which I learned from a trainee of mine who’s a cook, fabulous chef, is there’s a certain generation that grew up not indulging in vegetables for their diet.

Brangham: That’s a nice way to put it.

And so we’ll see a lot of folks for whom vegetables, actually, it’s not so easy to integrate vegetables into our lives.

So how do you help someone like that?

Well, most folks have at least one green vegetable they call their favorite.

So once you figure that out, a simple first step is, well, why don’t you just double or triple the amount of servings you have?

If you eat it once a week, eat it twice a week.

If you eat it once a month, why don’t you eat it once a week?

But that’s the key, is figuring out how somebody can take that first step.

That first step is crucial.

And this is part of the process that we’re going through, is understanding, bringing in all the experts, social scientists, psychologists, but importantly, the person themselves, listening to folks, what that first step is.

But going back to the science, what we also know is the body’s not that complicated.

So it’s not like if you just do one step in one category, it only influences that one category.

Think of this score as levers that are all interconnected.

And if you start moving one in the right direction, the others will move slightly.

For instance, if you cut back on your drinking, you might feel better in the morning and be more apt to exercise.

You might have slept better the night before.

Rosand: Your sleep could improve.

Your blood pressure could go down.

Exactly.

But oftentimes, we’ll have discussions about, well, what would have the biggest impact?

Brangham: Right.

Bang for the buck, doc.

I think it’s bang for the buck.

Physical activity is amazing.

Exercise is an amazing, an amazing drug.

It’s not a drug, but it has all of the positive effects on the brain and the body that a really potent drug would have if we could figure out what that drug is.

Brangham: Right.

We talked with Euan Ashley at Stanford, who’s doing this long, longitudinal study about the impacts of exercise.

And he said, if you could just take 10% of the impact of exercise and make it into a pharmaceutical, you’d be the richest pharmaceutical company in the world.

And again, it’s available to all of us in whatever way you want to deploy that for free.

That’s a nice way to think about it.

I would say the same thing for social relationships, positive social relationships.

If a pharmaceutical company could figure out what the drug equivalent of that could be, that I think... Brangham: The friendliness drug?

The friendship drug?

Well, that gave you the impact of all of that.

I think also meaning and purpose in life.

These are areas we don’t... Brangham: Can we stay on that one for a second?

Meaning and purpose in life.

That’s a tough prescription coming from a doctor to say to someone, where do you find this?

How can you find more of it?

That seems like a bit of a challenge.

Well, I think you have to know yourself.

You have to be open to what your aspirations are.

Conversations are kind of critical to figure that out, but so many people are deriving meaning and purpose in life from helping others, whether it be family members, whether it be a friend or somebody who you’ve felt connected to.

So a conversation can go a long way to help an individual identify where they’re deriving it, and once you’ve helped somebody identify where they’re finding meaning and purpose, it’s as if something... I don’t know.

The world suddenly is a little bit in color.

Brangham: Interesting.

Like a different pair of lenses over your eyes.

Rosand: Yeah.

Yeah.

Well said.

Is part of the challenge here that you’re not offering to patients a new thing?

Like if you could say, "Just hang upside down for 30 minutes a day," or "Sit in a sauna for 4 hours once a week," like it’s a new novel thing, whereas what you’re telling us is what it feels like we have been telling people for a generation, "Eat better, sleep better, "exercise, bring your blood pressure down."

Like, is that part of the challenge here that is, as you mentioned, this is old wine in new bottles?

Yeah.

I think that is part of what’s happening.

Whether it’s a challenge or not, I would offer it’s also simplicity.

We are inundated with messages from people who want to sell us all these wonderful promises.

This is your score.

The brain care score is the fruits of a generation or two of scientists and patient volunteers, people like you and me who participate in studies.

It’s all here for you to use.

And you don’t have to buy anything necessarily.

You do it your way.

The nice thing about the brain care score is you bring it to your doctor, and we’ve heard this again and again from patients.

They bring the brain care score to their doctor and they say, "I heard about this.

"I want to raise my score.

Can you help me?"

And that transforms the experience of being in the doctor’s office, because suddenly it’s not the doctor preaching.

It’s the doctor taking the score and saying, "All of this is great."

And it can change the tenor of the conversation.

So I think part of what we’re doing is we’re resetting how to think about health care from the lens of how to prevent or delay dementia.

Is there any concern that people could hear about this research and think, "Well, my mom ended up getting dementia anyway," that somehow it’s a failing if you do end up getting dementia?

Well, one of the things we’ve learned, we’ve done studies to ask the question, do people with a higher score, but... High in this case means higher risk factor?

No.

One of the things about the score is the higher your score, the lower your risk.

Brangham: I see.

You want a high score.

- You want a high score.

Brangham: Like in mathematics.

You want a high score.

The higher your brain care score, the lower your risk of dementia, stroke, and depression and other chronic conditions, actually.

But what we’ve done is we’ve been able to look at individuals who have a high genetic risk for conditions like dementia, depression, stroke.

And what we find is that those people who have that risk from their inherited genetics yet have higher scores have a lower risk of getting those conditions than their compatriots who have lower scores but the same genetic inheritance.

So there’s always something you can do.

And I’ll offer this as a really reassuring approach.

The number one thing I do with individuals who come in with early cognitive decline is ask about alcohol.

You’d be amazed what stopping alcohol completely can do even when we’ve begun to lose some of our cognitive function because we have early mild cognitive impairment.

So I think we have to get out of the stance of fatalism, understandable as it might be that we have it.

Because there is nothing more terrible than watching somebody with dementia and then knowing that you’re at higher risk of it for a variety of reasons including genetics.

Brangham: Right.

We have about a minute left.

Where can people find this score?

How do they go about doing it for themselves?

So you can go to the website of the coalition.

It’s globalbraincare.org.

The score is now I think in 10 languages.

It’s simple to use, and our hope is that people will use it, use it, share it, bring it to their doctor’s offices.

And meanwhile our job is to find all of the new risk factors that ought to be added to that score over time.

But the goal is really to give this to people so they can use it.

Brangham: Dr.

Jonathan Rosand, great to talk to you.

Thank you so much for being here.

It was my pleasure.

Thanks so much.

Before we go, we wanted to mention one other intervention that has shown some real promise helping stave off dementia.

And that is dancing.

[Dance music playing] Brangham: According to a 2003 study in the New England Journal of Medicine, older people who were frequent dancers, meaning those who danced more than once a week, had a 76% lower risk of developing dementia compared to those who didn’t dance nearly as often.

It’s a pretty striking result, and it came somewhat by surprise.

Back in the 1980s, researchers at the Albert Einstein School of Medicine in New York enlisted just under 500 elderly Bronx residents.

These were people in their mid-70s and 80s and they wanted to better understand the aging process.

So the researchers initially did all sorts of physical and cognitive tests on them and then just let them go about their daily lives.

Over the course of two decades, they’d occasionally rerun those same tests.

As we’ve been talking about today, participants who enjoyed things like challenging games, crossword puzzles or chess or did things like participating in group discussions with friends, they saw cognitive benefits, as did those who got various forms of exercise.

But it was those who were regular dancers who really stood out.

According to the study, quote, "dancing was the only physical activity "associated with a lower risk of dementia."

Researchers have suggested that dancing is such a powerful intervention because it combines so many positive activities.

It’s great exercise.

You have to remember complex steps, follow a beat and rhythm and maintain your balance.

And if you’re lucky, you get to do it with others.

OK, so we’ve all got our assignments now.

Get up on your feet, turn up the music and start moving.

That’s it for this episode of "Horizons."

Thank you so much for watching.

We’ll see you next week.

Announcer: Support for "Horizons" has been provided by... Steve and Marilyn Kerman and the Gordon and Betty Moore Foundation.

Additional support is provided by Friends of the NewsHour.

♪ This program was made possible by contributions to your PBS station from viewers like you.

Thank you.

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