News Release

Mid-Life High Blood Pressure And Smoking Speed Brain Aging And Increase Stroke Risk

Peer-Reviewed Publication

American Heart Association

DALLAS, March 5 -- In a study of elderly men, researchers found that mid-life health problems -- such as high blood pressure -- speed up aging of the brain and increase the risk for stroke during late-life. The study appears in this month's Stroke: Journal of the American Heart Association.

Using magnetic resonance imaging (MRI) to paint a detailed picture of the brain in later life, scientists were able to show that conditions such as high blood pressure, diabetes and increased alcohol consumption are, literally, good predictors of the shape of person's brain as he or she ages.

Charles DeCarli, M.D., author of the study, sponsored by the National, Heart, Lung and Blood Institute, says the new findings are part of a growing body of evidence that suggests that health behavior in mid-life can make a difference in how individuals function when they are in their 70s.

"Normally, as people age, their brains get smaller, and the "white matter," which is a type of nerve tissue in the brain, becomes damaged with age and the brain becomes smaller. These changes are associated with a decline in mental function," says DeCarli, associate professor of neurology and director of the Alzheimer's Disease Center at the University of Kansas.

But the risk factors -- especially high blood pressure and smoking -- tracked by DeCarli's team tend to speed the normal aging process.

"If you have these risk factors, they accelerate the aging process. High blood pressure and other risk factors accounted for about 15 percent of the abnomal tissue in brain structure. High blood pressure was the strongest risk factor," he says.

"These are the building blocks of risk prediction," he says. "The take-home message is if you've got high blood pressure -- or other risk factors in mid-life -- you better treat it."

DeCarli used MRI, an imaging technique that can make fine, cross-sectioned pictures of the brain, to study the size and shape of the organ and look for evidence of stroke and brain aging in a long-studied group of men now entering late life.

The men in the study are the 414 surviving members of the NHLBI Twin Study. They were examined on four occasions spanning between 1969, when the study was initiated, and 1997. Over the course of the study, participants were repeatedly examined to assess health status, with special attention given to risks associated with cerebrovascular disease, which included stroke and transient ischemic attacks (small strokes that resolve in about 24 hours).

In the last examination in 1997, the men, whose ages then averaged 72 years, were scanned with MRI to determine brain volume or size, changes in white matter, and evidence of vascular disease such as stroke. Comparing those pictures with information about individual's risk factors present at mid-life portrayed how behaviors like smoking and alcohol consumption and conditions such as high blood pressure and diabetes influenced the brain over time, according to DeCarli.

"MRI tells us about the continuum of brain disease," he says. "We can get a picture of the brain that shows problems that may not yet have visible symptoms."

An example, he says, is "silent stroke." Silent strokes occur in the small blood vessels in the brain. They are called silent strokes because there are no visible manifestations nor do they cause the classic signs of stroke, says DeCarli. Larger strokes -- which may be caused by a blood clot -- can paralyze or kill.

But signs of such disease are evident from MRI scans, says DeCarli. "Most of the conditions associated with stroke, thinned nerve tissue and reduced brain volume, we can identify with MRI. And our findings show that people at risk for these problems have many mid-life risk factors."

Co-Authors are B.L. Miller, M.D.; G.E. Swan, Ph.D.; T. Reed, Ph.D.; P.A. Wolf, M.D.; J. Garner, M.D.; L. Jack, B.S.; and D. Carmelli, Ph.D.

###

Media advisory: Dr. DeCarli can be reached at 913-588-6979. (Please do not publish telephone numbers.)



Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.