Early brain scans may offer a new way to detect Alzheimer’s in patients nearly a decade prior to its diagnosis, an advance that might aid in the development of effective treatments for the disease.
In a study published yesterday in the online edition of Neurology, researchers found that brain scans of healthy people showed signs of brain shrinkage in Alzheimer's-affected areas nearly a decade before the presence of the disease was confirmed by physicians. "The magnetic resonance measurements could be very important indicators to help identify who may be at risk of developing Alzheimer's dementia," says Leyla deToledo-Morrell, a researcher at Chicago-based Rush University Medical Center in Chicago who worked on the study. She added that should a drug therapy or treatment for Alzheimer’s be developed in the future, “those who are still without symptoms, but at great risk, would benefit the most from it.
The study involved two groups of healthy subjects in their 70s who had had brain scans at Rush University and at Massachusetts General Hospital/Harvard Medical School in Boston and were followed for an average of nine years. Of these participants, 50 individuals remained cognitively normal and 15 developed Alzheimer's disease.At the conclusion of the study, subjects with the highest amount of shrinkage in specific areas of the cerebral cortex were three times more likely to develop the disease.
"We also found that those who express this MRI marker of the Alzheimer's disease in the brain were three times more likely to develop dementia over the following 10 years than those with higher measurements," adds Brad Dickerson, MD, of Massachusetts General. Dickerson, who led the study, notes that while “these are preliminary results that are not ready to be applied outside of research studies right now”, the researchers are optimistic that the marker will be useful in the future.
Dickerson, de Toledo-Morrell, and their colleagues used traditional MRI equipment to conduct the study. Eli Lilly, General Electric, and other companies are developing special imaging agents that can detect proteins in the brain that signal the presence of Alzheimer's disease-related proteins. However, these tests are currently being developed to rule out Alzheimer's in patients who already have symptoms of the disease.