(GETTY IMAGES/CNN) - It's one of the worst diseases that strikes senior citizens by any standard.
It steals their memory, erases names, erases faces, family and friends - basically the victim's life.
It claims a half million lives a year, and researchers have developed a means of determining those most at risk for developing Alzheimer's disease in most cases.
There's hasn't been a good way to predict whose brains will get the plaques and tangles that destroy memory and concentration, and who will be spared.
But in a first-of-its-kind study, a simple blood test was able to predict who would get Alzheimer's.
"This is a really wonderful piece of science," said Dr. Howard Federoff, Neurologist, Georgetown University Medical. "It's the most significant observation that we've been able to report in my entire scientific career. "
The researchers looked at the blood of healthy elderly people checking for 10 fatty molecules called lipids.
Those who had lower levels of lipids were more likely to develop Alzheimer's, or the memory problems that precede Alzheimer's.
On average, the change, from healthy to sick, took just two years.
And the test was over 90 percent accurate.
The researchers, and the Alzheimer's Association, point out that other labs need to validate that this test really works... And even if all goes well, the test won't be in doctors' offices for several years.
So who would want a test to predict Alzheimer's?
After all, there's nothing you can do to stop it.
Federoff, the lead researcher in the study, says he'd want to know.
"I would want to plan," he said. "I would want to work with my family to make sure that I attend to the issues that are important to us."
But some people might not want to know that they're destined for a devastating disease.
Copyright 2014 GETTY IMAGES via CNN. All rights reserved.