Research published in the August 24 online issue of Neurology® reveals that biochemical changes occurring in the brains of normal people who might be at risk for Alzheimer’s disease can be detected by a brain-imaging scan.
The 311 study participants, who were a part of the population-based Mayo Clinic Study of Aging, were between the ages of 70 to 80 with no cognitive problems. Researchers tried to detect abnormalities in several brain metabolites that may be biomarkers for Alzheimer’s disease by using an advanced brain-imaging technique called proton MR spectroscopy.
The levels of brain amyloid-beta deposits or plaques, marking the first signs brain changes due to Alzheimer’s disease, were evaluated by PET scans. Additionally, participants had to take memory, language, and other skills tests.
Jonathan M. Schott, MD, of the Dementia Research Centre, University College London in England and a member of the American Academy of Neurology, said: “There is increasing evidence that Alzheimer disease is associated with changes in the brain that start many years before symptoms develop. If we could identify people in whom the disease process has started but symptoms have not yet developed, we would have a potential window of opportunity for new treatment as and when they become available to prevent or delay the start of memory loss and cognitive decline.”
Considerably high levels of brain amyloid-beta deposits were seen in 33% participants, who also tended to have high levels of myoinositol/creatine and choline/creatine (brain metabolites). Regardless of the amounts of brain amyloid-beta deposits, those with high levels of choline/creatine had lower scores on several cognitive tests.
Study author Kejal Kantarci, MD, MSc, of the Mayo Clinic in Rochester, Minn., and a member of the American Academy of Neurology, said: “This relationship between amyloid-beta deposits and these metabolic changes in the brain are evidence that some of these people may be in the earliest stages of the disease. More research is needed that follows people over a period of years to determine which of these individuals will actually develop the disease and what the relationship is between the amyloid deposits and the metabolites.”
Presently, diagnosis cannot be established with MR spectroscopy.