Alzheimer's Grips Brain Before Mental Decline
Biomarkers, Brain Scans Identify Healthy People at High Risk of Dementia
While the brain scans were able to detect the buildup of amyloid plaque in the brain, a different test -- one that checks for Alzheimer's biomarkers in cerebrospinal fluid -- may detect Alzheimer's risk even earlier.
Morris and colleagues studied one patient who eventually died with Alzheimer's disease. He was positive for the biomarker but his brain scan did not detect signs of Alzheimer's.
Kennedy says that's a hopeful finding. To him, it suggests that Alzheimer's disease is not one single entity, but may be a family of diseases that may respond to different treatments.
Morris notes that it's still too soon to be able to tell from brain scans or biomarkers exactly how long it will take for a healthy person with pre-Alzheimer's to develop dementia. But he expects this will eventually be possible.
"As experience accumulates, we will be able to determine in these people who carry lesions when they will get symptoms of Alzheimer's disease," he says. "It will not be straightforward. It will vary with a host of individual factors. But we can expect a day when we can tell people where they are in the course of preclinical Alzheimer's disease, and their risk of dementia in one or 10 or 20 years."
The Morris studies were funded with grants from the National Institute on Aging, an anonymous foundation, and by the Knight Alzheimer's Research Initiative of Washington University. The studies appear in the December issue of Archives of Neurology.