Of 42,801 participants with neuroimaging data available as of January 25, 2023, 37,463 were retained in our study. We first filtered for individuals with available APOE genotype and neuroimaging data, as well as active consent as of April 25, 2023. Individuals with neurological diseases were then removed (Table S1 in supporting information) and then filtered such that all remaining participants were genetically not third‐degree or closer relatives (Text S1 in supporting information). See Figure S1 in supporting information for a graphical summary and Table S2 in supporting information for the distribution of APOE genotypes by sample filtering step. Only those with APOE ε3/ε3, ε3/ε4, ε4/ε4, or ε2/ε3 were included in our analysis. The age range of the participants spanned from 44 to 82 with a mean of 63.9 years (standard deviation [SD] = 7.7).
