Test May Spot Alzheimer's in Early Stages

Oct. 5, 2005 -- An inexpensive, painless brain test may be able to predict who will develop Alzheimer's disease when the first signs of memory loss begin to emerge.

Alzheimer's disease affects millions of people worldwide, but researchers say there has been no easy way to identify the devastating disease at its earliest stages -- a time when early treatments may help delay or prevent further memory loss and dementia.

A new study shows that computer analysis of a commonly used test called an electroencephalogram ( EEG), which measures electrical activity in the brain, may be able to predict which people in their 60s and 70s with slight memory loss will develop Alzheimer's in the next decade.

"Our results suggest that quantitative analysis of the EEG is sensitive to the earliest signs of the dementing process," says researcher Leslie S. Prichep, PhD, associate director of the brain research laboratories at New York University School of Medicine, in a news release.

If further, long-term studies confirm these results, researchers say that the test may be used as one of the tools to evaluate a person's risk of developing Alzheimer's disease.

Brain Test May Predict Alzheimer's

In the study, published in the Neurobiology of Aging, researchers evaluated 44 people aged 64 to 79 who felt that they had some decrease in mental abilities; however, tests showed their brain function was normal for their age.

The participants were given an EEG at the start of the study and several more times over the next seven to nine years. During this time, 27 of the participants developed mild cognitive impairment or full-blown dementia, typical of Alzheimer's disease, and 17 remained stable.

Using a mathematical formula to analyze the EEGs, researchers found that certain features of the brain wave patterns in the first EEG scan were associated with future risk of Alzheimer's and dementia.

Researchers say the EEGs were nearly 95% accurate in identifying those who would suffer from further memory loss and cognitive decline and those whose brain function would age normally.

An EEG takes about 30 minutes to perform and involves placing electrodes on the scalp to measure brain wave activity.