TUESDAY, Dec. 23 (HealthDayNews) -- Researchers studying Down syndrome patients believe they have found a way to detect Alzheimer's disease before symptoms of dementia appear.

Brain scans of adults with Down syndrome showed increased metabolic activity in the temporal cortex, the same region of the brain where Alzheimer's disease commonly develops.

The researchers at the University of California at Irvine School of Medicine speculate Alzheimer's may begin with a similar metabolic increase, because Down syndrome often leads to dementia during adulthood. Their findings appear in the Dec. 23 issue of Neurology.

If so, early detection of Alzheimer's could be accomplished through positron imaging tomography (PET), a brain scan that employs radioactively labeled glucose to show the brain at work.

In diseased brains, damaged neurons have to work harder to maintain their effectiveness, and those efforts show up in a PET scan, says Dr. Richard Haier, professor of pediatrics and principal researcher. As the disease progresses, the damaged neurons are destroyed and the metabolic rate decreases.

"But to confirm this, further imaging tests must be done on the Down syndrome people as dementia progresses," Haier adds.

More information

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