THE ASSOCIATION BETWEEN PERSONALITY AND TAU PET DEPOSITION IN COGNITIVELY NORMAL OLDER ADULTS: FINDINGS FROM THE KNIGHT ALZHEIMER DISEASE RESEARCH CENTER

Abstract

Personality traits, such as neuroticism and conscientiousness, are associated with the onset of Alzheimer disease (AD) dementia, and may represent potential risk and resilience factors, respectively. Additionally, neuroticism has been associated with AD-related neuropathology including β-amyloid and neurofibrillary tangles at autopsy. However, the in vivoassociation of personality traits and AD pathophysiology in cognitively normal (CN) individuals remains largely unexamined. This study examined the cross-sectional relationship between personality traits and regional PET tau deposition in CN older adults. Ninety-four CN (Clinical Dementia Rating (CDR) 0) older adults from the Knight Alzheimer Disease Research Center cohort completed the NEO Five-Factor Inventory to assess traits of neuroticism, extroversion, openness, agreeableness, and conscientiousness and underwent [18F]-AV-1451 tau-PET and [18F]-AV-45 β-amyloid-PET imaging. Tau levels were assessed in four regions including the amygdala, entorhinal cortex, inferior temporal cortex, and lateral occipital cortex (Figure 1), which are known to display early tau accumulation in AD. β-amyloid was examined as a composite measure from previously well-defined AD-related regions. We utilized linear regression models, adjusting for age and sex, to evaluate the association between the each of the personality traits and regional tau accumulation. Secondary analyses additionally adjusted for β-amyloid deposition. Elevated neuroticism scores were significantly associated with higher tau accumulation in the amygdala (p=.003), entorhinal cortex (p=.031), and inferior temporal cortex (p<.001) (Figure 2a). In contrast, extroversion, openness, agreeableness, and conscientiousness were not associated with tau deposition for any of these regions (Figure 2b-e). After additionally adjusting for β-amyloid, results remained essentially unchanged (Table 1). Our results indicate that increased neuroticism is associated with higher tau pathophysiology in AD-vulnerable regions in CN participants. These effects were not driven by β-amyloid, suggesting a unique relationship between neuroticism and tau levels. High neuroticism scores are associated with increased levels of stress, which in turn may serve as a potential risk factor for tau accumulation. Alternatively, personality has been shown to change with the onset of AD, thus increased tau levels may affect neuroticism scores. While, future longitudinal studies are needed to determine directionality, our findings suggest early associations between neuroticism and tau accumulation in CN adults. Tau-PET regions of interest. Association between personality traits and tau-PET Covariate adjusted residuals from linear regression models examining the relationship between tau-PET SUVR in the inferior temporal cortex and neuroticism (A), extroversion (B), openness (C), agreeableness (D), and conscientiousness (E).