Subjective Cognitive Complaints, Personality and Brain Amyloid-beta in Cognitively Normal Older Adults

Objective: Subjective cognitive complaints in otherwise normal aging are common but may be associated with preclinical Alzheimer disease in some individuals. Little is known about who is mostly likely to show associations between cognitive complaints and preclinical Alzheimer pathology. We sought to demonstrate associations between subjective complaints and brain amyloid-beta in cognitively normal older adults; and to explore personality factors as potential moderators of this association. Design: Cross-sectional observational study. Setting: Clinical neuroimaging research center. Participants: Community volunteer sample of 92 healthy older adults, screened for normal cognition with comprehensive neuropsychological evaluation. Measurements: Subjective cognitive self-report measures included the Memory Functioning Questionnaire (MFQ), Cognitive Failures Questionnaire, and the Subjective Cognitive Complaint Scale. Personality was measured with the NEO Five Factor Inventory. Brain amyloid-beta deposition was assessed with Pittsburgh compound B (PiB)-PET imaging. Results: One of three cognitive complaint measures, the MFQ, was associated with global PiB retention (standardized beta - -0.230, p - 0.046, adjusting for age, sex and depressive symptoms). Neuroticism moderated this association such that only high neuroticism individuals showed the predicted pattern of high complainte-high amyloid-beta association. Conclusion: Evidence for association between subjective cognition and brain amyloid-beta deposition in healthy older adults is demonstrable but measure-specific. Neuroticism may moderate the MFQ-amyloid-beta association such that it is observed in the context of higher trait neuroticism. Subjective cognitive complaints and neuroticism may reflect a common susceptibility toward psychological distress and negative affect, which are in turn risk factors for cognitive decline in aging and incident Alzheimer disease.