Personality in Relation to Biomarkers as Risk Factors for Dementia

Dr. Janet M. Duchek

Summary:It is well known that the pathological changes associated with Alzheimer’s disease (AD) are present for a decade or more before the behavioral symptoms are apparent. Thus, there is a need for sensitive, noninvasive behavioral markers to identify the earliest detectable signs of AD. Although much of the past work has focused on cognitive markers, personality has been identified as a non-cognitive risk factor for early stage AD. This presentation addresses the following questions: (1) Does personality discriminate between healthy aging and the earliest stage of AD? (2) Does personality predict conversion from healthy aging to early stage AD? and (3) Do AD biomarkers mediate any observed relationship between personality and dementia status and/or conversion? Both self- and informant ratings of personality were obtained utilizing the NEO-FFI in a large well-characterized longitudinal sample of cognitively normal older adults (N = 436) and individuals with early stage AD (N = 74). Biomarkers included amyloid imaging, hippocampal volume, CSF Aβ42, and CSF tau. Consistent with previous literature, the personality traits of neuroticism and conscientiousness discriminate healthy aging from very early AD and conscientiousness predicted conversion to AD. There was little evidence that AD biomarkers mediated the relationship between personality and dementia status/conversion underscoring the role of personality as a unique early behavioral marker.