One study using the NIA-AA criteria found that the proportion of preclinical AD (NIA-AA stage 1–3) was higher in APOE ε4 carriers compared to noncarriers.9 Another study found that APOE ε4 carriers more often had preclinical AD.8 In a study on cognitively normal persons in the age span of 30 to 90 years, APOE ε4 carriers more often had amyloid positivity on PET after 70 years of age.36 Here, APOE is linked to Alzheimer disease.