 - Participants 60 to 64 years of age must also have 1 of the following 3 conditions: a a positive family history for dementia minimum of 1 first degree relative, b a previously known apolipoprotein E, ε4 allele APOE ɛ4 genotype, c a previously known biomarker status demonstrating elevated amyloid accumulation in cerebrospinal fluid CSF or positron emission tomography PET 