Assessment technique lets scientists see brain aging before symptoms appear

UCLA scientists have used innovative brain-scan technology developed at UCLA, along with patient-specific information on Alzheimer's disease risk, to help diagnose brain aging, often before symptoms appear. Published in the January issue of Archives of General Psychiatry, their study may offer a more accurate method for tracking brain aging.

Researchers used positron emission tomography (PET), which allows a window into the brain of living people and specifically reveals plaques and tangles, the hallmarks of neurodegeneration. The PET scans were complemented by information on patients' age and congnitive status and a genetic profile. Combining key patient information with a brain scan may give us better predictive power in targeting those who may benefit from early interventions, as well as help test how well treatments are working, said study author Dr. Gary Small, who holds UCLA's Parlow-Solomon Chair on Aging and is a professor at the Semel Institute for Neuroscience and Human Behavior at UCLA.

Scientists took PET brain scans of 76 non-demented volunteers after they had been intravenously injected with a new chemical marker called FDDNP, which binds to plaque and tangle deposits in the brain. They reported that older age correlated with higher concentrations of FDDNP in the medial and lateral temporal regions of the brain, areas involved with memory, where plaques and tangles usually collect. This group demonstrated higher FDDNP levels in the frontal region of the brain, also involved in memory, than study participants without allele. We found that for many volunteers, the imaging scans reflected subtle brain changes, which take place before symptoms manifest, said Small, who is also director of the UCLA Longevity Center.

Currently, the new FDDNP-PET scans are used in a research setting, but clinical trials are in development to bring the technology to wider patient use. The study was funded by both government and nonprofit agencies, including the National Institutes of Health, the U.S. Department of Energy, the Ahmanson Foundation, the Larry L. Hillblom Foundation and the Tamkin Foundation.