What's Good for the Heart Is Good for the Head

By JANE E. BRODY

Published: March 22, 2005

For decades I've been pleading with my readers to adopt healthy habits to prevent heart disease and possibly some cancers. Now there's another organ, the brain, that these measures may protect.

Growing, scientifically sound evidence suggests that people can delay and perhaps even prevent Alzheimer's disease by taking steps like eating low-fat diets rich in antioxidants, maintaining normal weight, exercising regularly and avoiding bad habits like smoking and excessive drinking.

Several other practices - including remaining socially connected and keeping the brain stimulated by reading, doing puzzles and learning new things - also appear to protect the brain against dementia.

Achieving such protection is no minor matter. Nearly half of the people who live past 85 develop this devastating disease that ultimately divorces them from reality and those who love them. With 77 million baby boomers headed toward advanced age, much can be gained from postponing this most common form of dementia, if not preventing it entirely.

An estimated 4.5 million Americans now have Alzheimer's, and the number has doubled since 1980, as more people reach older and older ages. Alzheimer's already costs Medicare three times as much as any other disease. By 2010, Medicare costs for people with Alzheimer's are expected to rise by more than 50 percent, to $49.3 billion from $31.9 billion in 2000. Now, half of all nursing home costs are related to dementia.

Alzheimer's is a progressive brain disorder that gradually destroys a person's memory and ability to learn, reason, make judgments, communicate and carry out normal activities of daily life.

Two changes in the brain are characteristic: abnormal microscopic structures called amyloid plaques that accumulate outside brain cells and tangles of a protein called tau that form inside brain cells. Because these changes are now seen only in autopsies, coming up with early diagnoses and tests for the disorder is a major challenge.

Early signs may include forgetting recently learned information, performing familiar tasks only with difficulty, misplacing things (putting shoes in the refrigerator, for example), fumbling for the right word for an ordinary object (like a toothbrush) and forgetting where you are or how you got there. Personalities can also change, and patients can become paranoid, suspicious, fearful or extremely confused. Some lose their judgment and suffer from mood swings or loss of initiative.

Built for Durability

The brain is a very forgiving organ. It has a very large reserve capacity and can withstand an extraordinary number of "hits" and bounce back from them. Witness how well some people recover from serious strokes and brain trauma. Likewise, autopsies often reveal considerable brain changes associated with Alzheimer's disease among subjects who showed no symptoms of dementia during their lives.

But when the brain is otherwise compromised, it may not be as able to protect itself against the encroaching damage of Alzheimer's.

So how do measures to prevent heart disease and stroke protect the brain? In an interview, Dr. Laurel Coleman, a geriatric physician in Augusta, Me., and a member of the national board of the Alzheimer's Association, explained that increasing evidence suggested an overlap between vascular disease in the brain and what happens to the brain in people who develop Alzheimer's.

The presence of vascular disease - the kind that can lead to a heart attack or stroke - seems to decrease the brain's ability to fend off the effects of Alzheimer's-related damage and increase a person's chances of showing obvious signs of dementia.

"Some people," Dr. Coleman said, "have pure Alzheimer's disease and some have pure cerebral vascular disease. But most have a mix of the two." The same risk factors that raise a person's chances of having a heart attack or stroke - high cholesterol and blood pressure, excess weight, smoking, lack of exercise - also raise the risk of developing dementia, she explained.