Detecting Alzheimer’s Before You Have Symptoms

Long before any doctor diagnoses the disease, most people who have Alzheimer’s have done something that is very out of character, embarrassing or even dangerous to themselves or others. The Alzheimer’s label rarely surprises family members or friends—rather, it just gives a name to the changes they have already been witnessing.

When will Alzheimer’s patients have the luxury of getting their diagnosis in the privacy of their doctor’s office, early enough so they can still comprehend the news in time to do something to stop the disease’s progress (assuming treatments become available)? Researchers who are developing the technology for early diagnosis predict that this may happen as soon as five years from now. Here are a few examples of what the scientists are working on:

With a type of magnetic resonance imaging (MRI) used primarily in research studies, researchers compared the brains of two groups of women. A high-risk group in their late 50s had both a family history of dementia as well as the apolipoprotein E4 allele (APOE4), a genetic variant that increases a person’s chances of getting Alzheimer’s. A comparison group in their late 60s had no extra risk factors. All of the women did fine on an extensive set of memory and intelligence tests.

The MRI assessed the brain’s white matter, which is made up of the fibers that connect one brain region to another. Myelin insulates these fibers, but that insulation thins as people age. Despite their normal cognitive abilities, the women carrying the genetic risk for Alzheimer’s had changes in these fibers that were not caused by aging and were similar to those seen in people with the disease.