Testing For Alzheimer's, Before It's Too Late

Approximately 5.3 million Americans have Alzheimer's disease. About a million also have memory loss called "mild cognitive impairment."

Barbara Gautier, 76 is participating in an Alzheimer's trial at New York University's Center of Excellence on Brain Aging at the Langone Medical Center.

"I'll forget the names of movies, a friend's name," Gautier told CBS Evening News medical correspondent Jon Lapook M.D.. "Sometimes the day of the week."

Gautier admits she has "senior moments". She's taking part in the study to find out if its something worse.

When Memory Loss Signals Alzheimer's

In cases of Alzheimer's, brain changes are likely to occur at least ten years before memory loss.

Proteins called amyloid and tau are thought to short-circuit communication between nerve cells and destroy brain tissue. Spinal fluid drawn from the back can reveal certain combinations of those proteins that are typical for the disease.

Today's study in the Archives of Neurology not only found those telltale signs - or biomarkers - in the spinal fluid if 90 percent of those patients with the disease, they also found them in 72 percent of those with "mild cognitive impairment."

And, most importantly, in 36 percent of people who appeared normal.

"We have to go to very early patients who have just the beginnings of Alzheimer's in their brains and those are the people we need a way to identify to test the treatments," said Stephen Ferris, M.D. of the Alzheimer's Disease Center at NYU. "That's why these spinal fluid tests are going to be extremely important over the next few years."

One way to look at it: Detecting Alzheimer's before you have symptoms is like finding high cholesterol before a heart attack.

But unlike statins for high cholesterol, we don't have any really effective treatment for Alzheimer's.

However, researchers feel some of the medicines that have failed in trial involving advanced Alzheimer's might actually work if they were given sooner.