Using special MRI methods, researchers have identified a pattern of regional brain atrophy in patients with mild cognitive impairment (MCI) that indicates a greater likelihood of progression to Alzheimer's disease.
The findings are published in the online edition of Radiology .
"Previously, this pattern has been observed only after a diagnosis of probable Alzheimer's disease," said the study's lead author, Linda K. McEvoy, Ph.D., assistant project scientist in the Department of Radiology at the University of California San Diego School of Medicine in La Jolla. "Our results show that some individuals with MCI have the atrophy pattern characteristic of mild Alzheimer's disease, and these people are at higher risk of experiencing a faster rate of brain degeneration and a faster decline to dementia than individuals with MCI who do not show that atrophy pattern."
According to the Alzheimer's Association, more than five million Americans currently have Alzheimer's disease. One of the goals of modern neuroimaging is to help in early and accurate diagnosis, which can be challenging. There is no cure for Alzheimer's disease, but when it is diagnosed early, drug treatment may help improve or stabilize patient symptoms.
In Alzheimer's disease, nerve cell death and tissue loss cause areas of the brain to atrophy. Structural MRI allows radiologists to visualize subtle anatomic changes in the brain that signal atrophy. MCI is associated with an increased risk of progression to Alzheimer's disease. Rates of progression vary. Some patients progress rapidly, while others remain stable for relatively long periods of time.
For the study, Dr. McEvoy and colleagues set out to determine if they could identify a pattern of regional atrophy characteristic of mild Alzheimer's disease in order to aid in the prediction of cognitive decline in patients with MCI.