Memory-loss test may be first clue to Alzheimer's

6/18/2001

“These test results show that you have a high risk for developing Alzheimer's disease,” says the doctor. “Nobody can foresee the future, and there's scientific uncertainty, but 50 percent of people with test results like these develop AD within four years.”

Would you take that test? Until now, it would have made little sense.

Early treatment is the main reason for early diagnosis and testing to identify risk factors. With no treatment, early diagnosis - especially of a disease as bleak as Alzheimer's - might just mean early heartache.

That situation, however, is quietly changing for AD, which affects more than 4 million Americans. AD involves loss of memory and other brain functions needed to perform everyday activities and live independently.

A new medical front is opening in the battle against AD. Its objective: Finding ways to treat and slow the advance of mild cognitive impairment (MCI). Some experts regard MCI as early Alzheimer's disease. Others view it as a separate disorder that is only a risk factor for developing AD.

MCI involves a mild loss of the ability to remember - but a loss more severe than ordinarily occurs in normal aging.

Almost everyone experiences momentary memory lapses with advancing age. People misplace the car keys, forget a new neighbor's name, go to the supermarket for bread and return home without it.

Individuals with MCI, however, experience more frequent and troublesome memory lapses than other people of the same age and education level. They forget conversations that took place a few hours ago; read a story in the newspaper and remember only the first few sentences, meet those new neighbors down the street and forget having met them.

MCI does not involve confusion about how to perform everyday activities, disorientation about the day of the week or the year, or other cognitive problems that occur in AD. On tests that measure these abilities, people with MCI score as well as healthy people of the same age.

Pioneering studies by researchers such as Dr. Ronald Petersen and his associates have established the link between MCI and AD. He directs the AD Treatment Center at the Mayo Clinic in Rochester, Minn.

About 12 percent of people with MCI develop Alzheimer's Disease each year - compared to 2 percent of people without MCI. Within four years after diagnosis of MCI, about 50 percent of individuals have AD. Within eight years, almost all have AD.

Studies like that have led experts to recommend that older people and their families, and doctors, pay more attention to mild memory loss that often is dismissed as “normal” or unimportant.

If it does result from MCI, there is a chance for treatment with drugs like Aricept, or food supplements such as high doses of vitamin E, that may reduce the risk of AD. But that window of opportunity for the person with MCI closes quickly. Once AD develops, it may be too late.

The National Institutes of Health in 1999 began a three-year study of Aricept and high-dosage vitamin E (1,000-2,000 units per day) for MCI. Other studies are checking whether estrogen, popular arthritis drugs called COX-2 inhibitors, and other medicines can treat MCI.

Doctors may suspect MCI on the basis of a patient's symptoms. Several simple tests, including the Folstein Mini-Mental Status Examination (MMSE), can help to diagnose MCI.

MCI is one of those conditions in which the clock is ticking, moving an individual closer to an incurable disease.

People diagnosed with MCI may decide, after discussions with the doctor, to grasp the opportunity for treatment while there still is time - even though study results are not in.

Michael Woods is the Blade's science editor. Email him at mwoods@theblade.com.