Hoping to keep your mental edge as you get older? Look after your heart, a recent analysis suggests, and your brain will benefit, too.
A research team led by Hannah Gardener, an epidemiologist at the University of Miami, analyzed a subset of data from the Northern Manhattan Study, a large, ongoing study of risk factors for stroke among whites, blacks and Hispanics living in the Washington Heights neighborhood of New York City.
The scientists wanted to see how people in their 60s and 70s would do on repeated tests of memory and mental acuity six years later — and, specifically, what sort of subtle differences a heart-healthy lifestyle might make to the brain, beyond the prevention of strokes. Their findings appear in a recent issue of the Journal of the American Heart Association.
In this particular study, the researchers started with more than a thousand people who'd had their cardiovascular health assessed using measures that the American Heart Association has dubbed Life's Simple 7.
These seven factors known to benefit the heart and blood vessels include maintaining a normal body weight and good nutrition, not smoking, getting exercise regularly and keeping blood pressure, cholesterol and blood sugar levels under control.
To measure thinking skills, Gardener's team used a variety of tests of memory, judgment, the ability to plan, mental quickness and other sorts of problem solving.
The results were striking: Across all demographic groups, the people who had higher scores on the measures of cardiovascular health did better on the mental tests than those who scored low. And a check several years later of mental acuity showed that the apparent brain benefits of a heart-healthy life persisted. The higher a person's score on "Life's Simple 7" the better.
"When we looked at changes in their brain health over time they showed less decline in several of the brain-health domains — including better processing speed, better memory and better executive function," Gardener says.
Keeping the executive function abilities of the brain high — the set of mental skills that include organizational ability, time management and impulse control, for example — can be especially important as we get older, says Dr. Clinton Wright, a neurologist at the University of Miami and a co-author on the study.
While mild memory issues, such as forgetting a familiar name or place, can be annoying, it's the brain's executive functioning that governs our ability to manage life, Wright says.
Skills like "managing your checkbook, doing your shopping, preparing your taxes," fall into this category, he says, and if people have trouble doing these everyday chores as they get older, it can jeopardize their independence.
More research is needed to identify exactly how cardiovascular health helps protect the brain, the scientists say, and to figure out whether there are certain times in life when factors like diet or exercise are more influential in this regard.
It's likely that the same things that can damage blood vessels in the heart, "can also lead to damage to tiny little microvessels that are everywhere in the body," Wright says. "And if those microvessels are in the brain — that can cause damage that has an impact on cognitive function."
Whatever the biological mechanism, the message is clear, doctors say: Keep your heart as healthy as possible and you'll likely help your brain, too.
STEVE INSKEEP, HOST:
If we look at the brain and the heart, researchers find that when the heart is healthy, so is the brain. NPR's Patti Neighmond reports on what that means for the elderly.
PATRICIA NEIGHMOND, BYLINE: Researchers looked at seven ways people can benefit their heart - not smoking, eating a low-salt diet, maintaining a normal body weight, getting exercise and making sure blood pressure, cholesterol and blood sugars are all under control. Then they looked at how well people did on brain tests. And University of Miami neurologist Clinton Wright says this is what they found.
CLINTON WRIGHT: What's good for the heart may be good for the brain.
NEIGHMOND: That's because the same things that can damage blood vessels in the heart can also damage blood vessels in other parts of the body.
WRIGHT: It can also lead to damage to tiny, little micro vessels that are everywhere in the body. And if those micro vessels are in the brain, that can cause damage that has an impact on cognitive function.
NEIGHMOND: Researchers analyzed data from a large ongoing stroke study in New York City. For this analysis, they looked at about 1,000 people and tallied up how many heart-healthy factors, like not smoking and eating a healthy diet, people had. Then they looked at how well they did on cognitive tests.
WRIGHT: Like list learning, tasks for testing memory, little problems that people had to solve to see how fast they could do things and how well they could plan and problem solve.
NEIGHMOND: At the time, they were on average 72 years old, about the age when memory and quick thinking can decline. Those with strong hearts did far better on the brain tests. And this was across racial lines. Most people, 65 percent, were Latino. Nineteen percent were black. Sixteen percent were white.
And when researchers looked at brain function over time, the findings were similar. University Of Miami epidemiologist Hannah Gardener says six years later, when people were on average 78 years old, once again, those with good heart health performed better on brain tests.
HANNAH GARDENER: When we looked at changes in their brain health over time, they showed less decline in several of the brain health domains, including processing speed, better memory and better executive function.
NEIGHMOND: And even though people often notice and focus on memory problems, neurologist Clinton Wright says it's the brain's executive function that can have a greater impact on the quality of life.
WRIGHT: So abilities to plan and organize and problem solve, and those abilities are so important for older people to maintain their independence - you know, managing your checkbook, doing all your shopping, you know, preparing your taxes.
NEIGHMOND: And these are the sort of problems that can make it impossible for some people to continue living on their own. Unfortunately, neurologist Larry Goldstein with the American Heart Association says most Americans don't follow the recommended Heart Association guidelines.
LARRY GOLDSTEIN: Things such as not smoking, not drinking to excess, getting regular exercise, following a healthy diet that's low in sodium and maintaining a healthy body weight - those are not only associated with about an 80 percent reduction in the risk of stroke but may also help people's thinking over time.
NEIGHMOND: So the message is clear. Make your heart as healthy as possible and you'll likely help your brain, too. Patti Neighmond, NPR News. Transcript provided by NPR, Copyright NPR.