Title: What do Trajectories of Brain and Cognitive Aging Reveal about Risk for (and Protection from) Alzheimer’s Disease?
Abstract: An intriguing consensus has consolidated in many quarters that “the etiology of Alzheimer’s disease (AD) has proven to be more complex than expected” (NIH, PAR-15-356). The implications of this observation have led to accelerated attention to multiple new directions in AD theory, research, intervention, prevention, and translation. Among these new approaches are five that inform the perspective and research presented in this talk.
First, recent attention has focused not only on the complexity of the outcome condition (AD and related brain disorders) but also on the pathways and predictors preceding such diagnoses. Second, there is, however, a paucity of foundational information about distributional and directional characteristics of preclinical brain and cognitive trajectories. Third, although a number of biomarker and risk factor predictors of AD have been identified, it is an open question whether these are also early (or the best) predictors of differential pre-impairment trajectories. Fourth, the etiological complexity of emerging and differentiating neurodegenerative diseases indicate that multiple modalities of early bio-signals may operate dynamically and interactively to produce differential trajectories of change. Fifth, it is conceivable that precise trajectory analyses would reveal a spectrum of trajectory phenotypes, including (a) impairment and disease-bound pathways, (b) normal brain and cognitive aging, and (c) elevated and sustained pathways of brain and cognitive resilience. In sum, by elucidating the nature and range of preclinical trajectories, as well as the bio-signal predictors determining individualized pathways, it may be possible to identify new potential prevention targets.
This work is conceived and conducted in the leveraged and coordinated context of the 25-year Victoria Longitudinal Study (NIH) and the Canadian Consortium on Neurodegeneration in Aging (CIHR).
Bio: Roger A. Dixon (University of Alberta) is Professor of Psychology (Science) and a member of the Neuroscience and Mental Health Institute. He has held previous appointments at Max Planck Institute (Berlin) and University of Victoria (Canada), as well as several international guest positions (eg. Karolinska Institutet, Stockholm; Stanford Centre for Advanced Studies, California). His recent recognitions include a Canada Research Chair (Tier 1, 2003-2010, 2010-2017), the 2013-14 Baltes Award for Distinguished Career Research in Aging (from the American Psychological Association), and two U.S. National Institutes of Health (NIH) MERIT Awards. His research is conducted primarily in the context of two large-scale national and international projects. First, he is the PI and Director of the Victoria Longitudinal Study, which has been funded continuously for over 25 years by NIH and other sources and partners. It is a large-scale, multi-cohort, epidemiological study of neurocognitive, biological, biomedical, genetic, environmental, lifestyle, and functional changes affecting neurocognitive aging. Second, he is a PI of the Canadian Consortium on Neurodegeneration in Aging, a multi-disciplinary nation-wide investigation of multiple neurodegenerative diseases. The CCNA is funded by CIHR and partners and deploys cutting edge technologies in the domains of biomarkers, neuroimaging, genetic, neurocognitive, intervention, and clinical approaches to understanding Alzheimer’s disease and related dementias. Current research emphases include examining (1) dynamic, interactive, and synergistic functions of risk, protective, and resilience biomarkers representing multiple domains of brain aging and dementia, (2) how these biomarkers influence preclinical trajectories, transitions and clinical outcomes in healthy, normal, impaired, and neurodegenerative changes, and (3) omics-based biomarker discovery, validation, and translation in neurodegenerative disease.