Story highlights Dementia rates in people over 65 fell from 11.6 percent in 2000 to 8.8 percent in 2012

Experts credit improving educational levels and better control of blood pressure, diabetes

A new study finds that the prevalence of dementia has fallen sharply in recent years, most likely as a result of Americans' rising educational levels and better heart health, which are both closely related to brain health.

Dementia rates in people over age 65 fell from 11.6 percent in 2000 to 8.8 percent in 2012, a decline of 24 percent, according to a study of more than 21,000 people across the country published Monday in JAMA Internal Medicine

"It's definitely good news," said Dr. Kenneth Langa, a professor of internal medicine at the University of Michigan and a coauthor of the new study. "Even without a cure for Alzheimer's disease or a new medication, there are things that we can do socially and medically and behaviorally that can significantly reduce the risk."

The decline in dementia rates translates to about one million fewer Americans suffering from the condition, said John Haaga, director of behavioral and social research at the National Institute on Aging, part of the National Institutes of Health, which funded the new study.

Dementia is a general term for a loss of memory or other mental abilities that's severe enough to interfere with daily life. Alzheimer's disease, which is believed to be caused by a buildup of plaques and tangles in the brain, is the most common type of dementia. Vascular dementia is the second most common type of dementia and occurs after a stroke.

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