To assess whether global or regional changes in amyloid burden over 4 years predict early declines in episodic memory in initially amyloid-negative adults.
One hundred twenty-six initially amyloid-negative, cognitively normal participants (age 30–89 years) were included from the Dallas Lifespan Brain Study who completed florbetapir PET and a cognitive battery at baseline and 4-year follow-up. Standardized uptake value ratio (SUVR) change was computed across 8 bilateral regions of interest. Using general linear models, we examined the relationship between change in global and regional SUVR and change in episodic memory, controlling for baseline SUVR, baseline memory, age, sex, education, and APOE status.
In initially amyloid-negative adults, we detected a regionally specific relationship between declining episodic memory and increasing amyloid accumulation across multiple posterior cortical regions. In addition, these amyloid-related changes in memory persisted when we focused on middle-aged adults only and after controlling for atrophy in global cortical, hippocampal, and Alzheimer disease signature cortical volume.
Our results indicate that assessing regional changes in amyloid, particularly in posterior cortical regions, can aid in the early detection of subclinical amyloid-related decline in episodic memory as early as middle age. Future research incorporating tau and other markers of neurodegeneration is needed to clarify the sequence of events that lead to this early, subclinical memory decline.
Washington University nonprofit, honorarium University of Michigan, nonprofit, honorarium
1. Cognitive neuroscience of aging: Linking cognitive and cerebral aging 2nd Edition. New York, NY: Oxford University Press. Royalties from 2009 to present.
National Institute on Aging, R-37AG006265,Principal Investigator, 1983-2022 National Institute of Mental Health R01 MH084021, Coinvestigator, 2013 ? 2017 National Institute on Aging,R-01AG026589, Principal Investigator, 2007-20012 National Institute on Aging, R-01AGO15047, Principal Investigator 2002-2011 National Institute on Aging, RC1AG036003, Principal Investigator, 2009-2011
The Alzheimer's Association, Principal Investigator,IIRG- 09-135087' The Aging Mind Foundation, Dallas, TX The AWARE Society, Dallas TX
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