MAY / JUNE 2006

AROUND HARVARD

This article originally appeared in the April 2006 Harvard Men’s Health Watch and is provided courtesy of Harvard Health Publications.

Minding your mind: How to keep your brain young with proper care and feeding

The challenges

Thin hair, a gray beard, a little paunch, and a slight stoop are among the common signs of aging that produce little distress. Most men learn to accept a certain loss of physical prowess, energy, ambition, and sexual drive; in fact, healthy men learn to compensate for these gradual changes and to enjoy productive and happy senior years. But one of the major benefits is the combination of experience, judgment, and memory we call wisdom. Some 2,500 years ago, Sophocles observed, “Men in old age learn to be wise.”

Perhaps because wisdom is a treasured benefit, people fear losing it more than any other age-related disability. It’s not an idle fear. About 7% of 65-year-olds meet the medical criteria for cognitive impairment, and by 85, up to 40% of Americans suffer significant mental impairment.

Aging is inevitable. But research suggests that mental decline can be prevented. A comprehensive program that includes lifestyle changes and medical care can substantially reduce your risk of “losing it.”

The aging brain
Like every part of the body, the brain changes with age, and like other organs, the pace of change varies from person to person. Still, the average human brain shrinks by about 10% during maturity, with a corresponding increase in the volume of fluid that bathes the brain. More bad news: As many as 100,000 brain cells die every day during old age.

Dying cells and shrinking brains sound pretty grim, but there is good news, too. With more than 100 billion cells, a healthy brain can shrug off the loss of a few hundred million with relative ease. Exciting research further suggests that some damaged nerve cells can repair themselves and that the aging brain may actually be able to generate new cells. Even with a falling cell count, the mature brain can develop new connections between existing cells. Neurologists call the brain’s ability to develop structural changes “plasticity.” Plasticity enables older people to learn new things and to think creatively. But these positive changes are not automatic; plasticity depends on the combination of proper mental stimulation and good general health.

The aging mind
Age has an impact on even the best brains. New learning takes longer, new information is processed more superficially, and details tend to slip. Short-term memory typically weakens, but long-term memory is well preserved. And healthy elders show little decline in abstract reasoning, visual-spatial ability, and language skills. In fact, while these processes often slow down a bit, some cognitive functions, such as vocabulary, may actually improve with age.

Normal memory lapses
“Men are men,” Shakespeare tells us; “the best sometimes forget.” But while young men laugh off memory lapses, older men can be quite disturbed by innocent forgetfulness. The table below lists some of the important differences between normal memory lapses and signs of cognitive impairment.

Minor memory lapses may be normal and inevitable, but they are still annoying and embarrassing. The box below provides some tips on how to cope with age-related memory lapses.

Managing that senior moment
Memory lapses are normal, even universal. But they do increase with age, even in people with healthy bodies and brains. Here are a few ways to compensate:

   Write it down. Make lists, jot memos to yourself, and use a calendar to note your appointments and obligations.
   Rehearse. If you have a complex task or trip ahead, review all the steps in your mind until they become second nature.
   Simplify. Eliminate distractions. Make routine things automatic so you won’t waste mental energy on them; for example, always put your keys and eyeglasses down in the same place.
   Stay alert. Get enough sleep. Minimize your use of alcohol, sedatives, and even antihistamines.
   Reduce stress. The last thing you need is to be distracted by worry or anxiety.
   Concentrate. Work at learning new information by focusing your mind and repeating the information until it’s yours. Do one thing at a time.
   Be sure your hearing and vision are up to par. It can be hard enough to recognize a face, let alone identify one that’s blurred.
   Be honest and ask for help when you need it. “I’m having a senior moment; please remind me of your name.”

Cognitive impairment and dementia
People older than 50 who complain of memory loss but who function well on memory tests are considered to have age-associated memory impairment (AAMI). Despite the fancy name, AAMI is part of normal aging, and less than 1% of folks with AAMI go on to develop major problems.

Mild cognitive impairment (MCI) is more serious. It is diagnosed in older people who complain of memory loss and who score below healthy people of the same age on standard memory tests. People with MCI retain language skills and abstract reasoning, and they can function independently. But up to 50% of people with MCI eventually go on to develop full-blown dementia.

Dementia is diagnosed when cognitive impairment is severe enough to impair daily function. In most cases, it’s irreversible and progressive. Although dozens of diseases can cause dementia, two stand out: Alzheimer’s disease and vascular or multi-infarct dementia.

Dementia is a terrible way to live and a hard way to die. We’re starting to understand the causes of cognitive impairment, and ongoing research is sure to improve diagnosis, treatment, and prevention. But even now you can do a lot to cut your risk of memory loss in old age.

Vitamins, herbs, and hormones
Wouldn’t it be nice to have a simple supplement to preserve your memory? It would be nice, but it’s a long way from reality. The leading candidate is ginkgo biloba; hope is based principally on a 1997 study of 202 individuals with vascular dementia or Alzheimer’s disease. The herb appeared to stabilize or improve cognitive function and social performance, but the improvement was modest, and only 27% of the patients achieved the slight benefit. When the study was published, hope quickly turned to hype. Unfortunately, the ginkgo express continues to roll, even though a 2000 study of 214 people with age-associated memory impairment or dementia showed no benefit from the herb.

It’s much the same story for vitamin E. Although a single 1997 trial showed that very high doses of the supplement appeared to slow the progression of Alzheimer’s disease, there is no evidence that it will stave off dementia or improve working memory. In fact, studies of more than 1,000 elderly Pennsylvanians and another of nearly as many New Yorkers found no benefit from vitamin E or other antioxidants such as vitamins C and A, beta carotene, and selenium.

Although many women have been attracted to postmenopausal hormone replacement in the hope that it will preserve mental function, a 2003 study suggests that estrogen may actually increase the risk of dementia. For men, a 2001 study reported that testosterone therapy appeared to improve spatial ability and verbal memory in healthy men aged 50–80, but the study was small (25 volunteers) and brief (6 weeks). Despite aggressive claims for DHEA and melatonin, there is no evidence that they can boost mental function. Hormone supplements for your memory? Forget it.

Copyright 2006 Harvard Medical International