Posted on: Wednesday, August 28, 2002
Minor memory changes could signal Alzheimer's
By Tim Friend
USA Today
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| An Alzheimer's day care client at Hale Kakoo is escorted outside for a walk.
Advertiser library photo • April 1996 |
Where are my car keys? Which street was I supposed to turn on? What was the name again of that nice family who moved next door?
Everyone has slips of the memory. Forgetting where you put the keys is nothing to worry about. But when you can't remember what the keys are for, or retrace your steps to find them, it's time to face a new and frightening possibility.
A growing number of medical experts are viewing unusual lapses of memory in an otherwise healthy person — the kind often passed off as old-age senility — as a powerful new sign for the earliest stage of Alzheimer's disease.
This condition, diagnosed by a recent change in memory that affects a person's daily routine, is called mild cognitive impairment, says Ronald C. Petersen, director of the Mayo Clinic's Alzheimer's Disease Research Center, Rochester, Minn.
"These people do not look or act like people we associate with Alzheimer's disease," Petersen says. "But almost everybody can identify someone like this, and when I speak to doctors, they say they see this in their practices all the time."
Charlton Heston, who recently announced that his doctors had diagnosed him with "a neurological condition consistent with the signs of Alzheimer's disease," appears to fit the description. But only a small number of specialists worldwide are familiar with the condition.
For the moment, there are no lab tests to help physicians diagnose mild cognitive impairment, also known as MCI. But experts do know how to rule out other possible causes of memory lapses. Side effects of medication is one common reason. Vascular problems also are an issue.
"Not everyone who has memory changes is destined to develop Alzheimer's," says Steve DeKosky, director of the University of Pittsburgh Alzheimer's Research Disease Center. "But there are specific memory changes that neurologists and psychiatrists recognize."
After ruling out other causes and looking for the right clues, the diagnosis of Alzheimer's-related MCI is about 90 percent accurate. The clearest indicator of MCI is a recent change in memory beyond what most people at a given age are experiencing, says John Morris, Friedman professor of neurology at the Washington University School of Medicine, St. Louis, and head of the university's Alzheimer's Disease Research Center.
"The key word is change," Morris says. "We find that when people are in the very earliest stage of dementia they are less able to do the kinds of activities they have normally been engaged in. When there is a change in the ability to perform everyday activities such as driving an automobile, preparing a meal or conducting household finances, that is when we become suspicious."
Estimates could double
No one knows yet how many people in the United States have MCI, but Petersen, DeKosky, Morris and other experts suspect that when people begin to recognize it, the estimates of 4 million Americans with Alzheimer's could jump to 8 million or more.
What is known from studies is that 80 to 90 percent of cases of MCI progress to Alzheimer's disease within six to 10 years. That suggests millions of healthy people with only a troublesome memory loss face up to a decade of uncertainty with the label of Alzheimer's on their shoulders. The implications for patients, their families, the workplace and the nation's healthcare system are staggering, says Bill Thies, scientific director at the Alzheimer's Association headquarters in Chicago.
"This presents a real challenge for people who have to deal with a diagnosis of mild cognitive impairment," Thies says. "But because the diagnosis is coming at a much earlier time, people have more time to work on it. There is a sense now that there will be preventative treatments in the future, probably in a five- to 10-year time window. So you would like to catch people at the very earliest moments in the disease."
Catching MCI early and trying to delay, or even arrest, the progression to Alzheimer's is one of the most active areas of research financed by the National Institutes of Health. This year, NIH is spending $594.7 million on Alzheimer's research. Much of that is aimed at the early stages of disease. The National Institute on Aging is financing three MCI trials using the three approved Alzheimer's disease drugs and vitamin E. The drugs are Aricept, Exelon and Reminyl. Vitamin E may protect aging cells from oxidative damage.
NIA also is financing a $25 million study to prove whether the health supplement ginkgo biloba can delay progression, says Marcelle Morrison-Bogard, NIA associate director, Neuroscience and Neuropsychology Program. Ginkgo biloba is a tree extract touted for the ability to keep the mind sharp. Studies conflict on whether that's true, but the public spends more than $200 million a year for it anyway.
NIH also finances imaging studies that aim to give physicians diagnostic tools in the near future. Early data suggest PET scans and magnetic resonance imaging can detect changes in the brain in people with MCI.
Studies of risk factors are revealing that the same risks for heart disease hold true for Alzheimer's. People who exercise and maintain a healthy weight, have lower cholesterol, drink moderately and don't smoke are at lower risk.
"In Alzheimer's, we have moved from the stage of understanding the disease in the late phases to getting a handle on the very earliest stages," Morrison-Bogard says. "MCI is the epitome of how the field is moving back in time to ask what are the beginnings of this disease biologically and cognitively."
'Everything got clearer'
But the most important work begins at home, the experts say. People must change their view of Alzheimer's from the blank stare of the late-stage patient to an active person in the earliest stage of MCI. That means people need to pay closer attention to memory problems and seek medical advice.
Mary Heuer, 59, of St. Louis; Ramona Ptacek, 61, of Owatonna, Minn.; and Bruce Clarke, 81, of Bloomington, Minn., are facing the challenges of MCI and early stage Alzheimer's. Their mental status over the next few years will help reveal to the rest of the world whether Alzheimer's disease can be delayed or possibly stopped.
Ptacek and Clarke joined Petersen's MCI study of Aricept or vitamin E versus a placebo. Ptacek and Clarke do not know which pill they get. The trial will reveal in the next three to five years whether Aricept or vitamin E work.
Heuer is not enrolled in a study, but her disease may be slightly more advanced and warrants immediate treatment, Morris says. He is treating Heuer with Aricept and vitamin E.
"The second after I started the treatment, it was like a veil was taken away. Everything got clearer," Heuer says. "I feel like I am holding my own."
Many people with MCI may not want to wait until the MCI trials are finished to start treatment. Doctors can prescribe Aricept, Exelon and Reminyl for MCI even though they are approved only for late-stage Alzheimer's.
Memory change is the most common sign of MCI, but it is not the only one. Heuer first noticed a visual-spatial problem. She was driving like a drunk, unable to keep her car in her lane. The memory lapses came later at her job as an executive secretary.
"I began forgetting how to take shorthand. Then one day I sat down at the typewriter to do a letter and forgot what to do," she says. "I broke down and started crying. It was very scary."
She went to a doctor and was misdiagnosed with depression. Heuer sought a second opinion. That doctor asked her to take a simple test. She was presented with a piece of paper with a circle drawn on it and asked to fill it in with numbers like the face of a clock. Heuer drew the numbers outside the circle. She was referred immediately to Morris.
Ptacek's case is more common. She worked as a rural mail carrier for 20 years. She began having problems remembering where people lived. The memory lapses became so stressful that she retired, but she kept the problem to herself. Then she started forgetting how to get to the grocery store and restaurants.
Ptacek copes by using sticky note pads to remind herself of what daily chores need doing.
Clarke is the most typical case. At age 76, he began to lose his sense of direction. At first, he thought it was just part of aging.
A little later he started having trouble with names. Otherwise, Clarke is healthy and active.
"I know that now there is no cure for this," Clarke says. "It is a fact. It is a darn shame, but it happens to people. My daughter said to get out of the study and go take some Aricept. They won't tell me what pill I take. But I'm sticking with it. I'm satisfied this way. The study will help other people if it doesn't help me."
