Brain changes seen in Alzheimer's victims before memory loss

CHICAGO (AFP) - People who develop Alzheimer's disease or dementia exhibit brain structure changes years before they show any signs of memory loss, a study released Monday said.
The finding may allow doctors to identify people at risk for the cognitive problems that lead to the devastating brain disease, according to the US study.
The research is based on a small study involving 136 seniors over the age of 65 who were given brain scans and cognitive testing on a regular basis over a five-year period.
By the end of the study, 23 of the volunteers had developed a condition known as mild cognitive impairment (MCI) and, of those, nine went on to develop Alzheimer's disease, a progressive brain disorder which is on the rise in developed nations.
When the researchers compared the brain scans of the 23 individuals who went on to develop memory problems with the 113 volunteers who did not, they found that the first group had less gray matter in areas of the brain involved with memory processing than the second group even when their brain function was normal.
"We found that changes in brain structure are present in clinically normal people an average of four years before MCI diagnosis," said Charles Smith, author of the study and an expert on memory and aging at the University of Kentucky Medical Center in Lexington.
"We knew that people with MCI or Alzheimer's disease had less brain volume but before now we didn't know if these brain structure changes existed, and to what degree, before memory loss begins," he said.
Moreover, the individuals who later developed memory problems had lower scores on cognitive test scores at the beginning of the study compared to the other seniors in the study, although the scores were within normal range.
"These findings of structural changes in cognitively normal people before memory loss begins aren't surprising given Alzheimer's disease may be present for many years before symptoms of the disease begin to appear," said Smith.
The paper appears in Tuesday's issue of Neurology, the scientific journal of the American Academy of Neurology.