Correlations between APOE4 allele and regional amyloid and tau burdens in cognitively normal older individuals

Background:The correlations between apolipoprotein epsilon 4 (APOE4) status and regional amyloid, tau, and cortical thickness in cognitively normal elderly are not fully understood. Our cross-sectional study aimed to compare regional amyloid/tau burden, and cortical thickness according to APOE4 carrier status and assess correlations between APOE4 and Alzheimer’s disease (AD)-related biomarker burdens.Methods:We analyzed 185 cognitively normal participants from the Alzheimer’s Disease Neuroimaging Initiative (ADNI) cohort. Participants aged 55–90 with normal cognitive function were divided into amyloid ꞵ-positive (Aß+) APOE4 carriers (group 1, n=27), Aß+ APOE4 non-carriers (group 2, n=29), and Aß- normal controls (group 0, n=129). We compared amyloid depositions, tau depositions, and cortical thickness among the 3 groups and assessed correlations between APOE4 existence and imaging biomarkers adjusted for age and sex. Results:The participants in group 2 were older than those in the other groups. The regional amyloid/tau standardized uptake value ratios (SUVRs) did not differ between groups 1 and 2, but the amyloid/tau SUVRs in most regions were numerically higher (especially in the younger (Conclusions:We identified that the presence of APOE4 allele might be more highly associated with amyloid deposition than with other AD-related biomarkers such as tau or cortical thickness, especially in the younger group below 70 in cognitively normal elderly.