Decreases in Plasma Aβ1-40 Levels with Aging in Non-Demented Elderly with ApoE-ε4 Allele

This report examines plasma amyloid β proteins Aβ40 and Aβ42 and apolipoprotein E (apoE) levels and their relationships with age in non-demented older adults with (N = 32) or without the apoE-ε4 allele (N = 94). Aβ levels did not differ between the groups whereas the ε4 allele was associated with a significant reduction in plasma apoE. In subjects with the ε4 allele, increasing age was associated with significant reduction in plasma Aβ40. Subjects without the ε4 allele showed a significant positive correlation between Aβ40 and Aβ42 levels. There was also a significant correlation between plasma Aβ40 and apoE levels in all subjects.