Physical Activity in Old Age May Protect Brain

THURSDAY, Nov. 1 (HealthDay News) -- Older people who exercise regularly may reduce their risk of dementia and help keep their minds sharp, a new study suggests.

Physical activity may cut dementia risk by 40 percent and decline of thinking skills by as much as 60 percent, researchers say.

"Over the past three years, this has become a highly consistent finding," said Dr. Sam Gandy, associate director of the Mount Sinai Alzheimer's Disease Research Center in New York City, who had no part in the study.

"The best thing we can do for ourselves and our patients is to adopt a regular exercise routine," he said. "This delays or prevents dementia or slows progression so there is some benefit for everyone."

Dr. Ralph Sacco, chairman of neurology at the University of Miami Miller School of Medicine, said this study shows some convincing evidence that physical activity in an older population reduces the risk of vascular dementia. Vascular dementia results from reduced blood flow to the brain, typically because of strokes, and may lead to symptoms such as confusion, depression, agitation and problems with memory, attention or decision-making.

"Physical activity is one of the seven key health factors in the American Heart Association's definition of ideal cardiovascular health, and can also help to reduce stroke and improve brain health," Sacco said.

As the U.S. population ages, more emphasis will be placed on ways to reduce dementia and age-related cognitive (mental) decline, he added.

"Staying physically active is not only important to improve heart health, but can also promote better brain health," Sacco said.

The study was released online Nov. 1 in advance of publication in the December print issue of the journal Stroke.

The investigators, led by Dr. Ana Verdelho, a neuroscience researcher at the University of Lisbon, Santa Maria Hospital in Portugal, had more than 600 men and women in their 60s and 70s undergo brain scans at the start and end of the study to look for changes that indicate declining mental function. Almost two-thirds of the participants took exercise classes, walked or biked for 30 minutes a day three times a week.

During the study, the participants were asked about depression, quality of life and their ability to do common activities.

After three years, the researchers found 90 patients had developed dementia, including 54 with vascular dementia and 34 with the brain-robbing condition known as Alzheimer's disease. Another 147 displayed problems with mental ability, but not dementia, the researchers reported.

"We strongly suggest physical activity of moderate intensity at least 30 minutes three times a week to prevent cognitive [thinking] impairment," Verdelho said in a journal news release. "This is particularly important for people with vascular risk factors such as [high blood pressure], stroke or diabetes."

Ideally, the American Heart Association suggests men and women should engage in 150 minutes of moderate exercise every week or 75 minutes of vigorous exercise.

Among study participants, regular exercise was effective regardless of age, education, changes in the brain, or a history of stroke, the researchers noted.

Dr. David Katz, director of the Yale University Prevention Research Center, said it's known that Alzheimer's and vascular dementia share risk factors with other chronic diseases, such as coronary disease.

"We have long had reason to believe that the same lifestyle practices that defend against diabetes and heart disease defend against dementia as well," he said.

This study reaffirms that important association, Katz said.

"The health of the body and brain are indelibly linked, and caring well for the one benefits the other. One may think that exercise is mostly about conditioning muscles, but this study suggests it is just as important for preserving a well-functioning mind," he said.