APOE and Alzheimer disease: Comparing demographic and clinical characteristics between diagnoses, AD participants were older than CN and MCI participants (AD: 75.0 [SD: 7.85], MCI: 75.6 [SD: 7.13], CN: 72.9 [SD: 6.12], p < 0.001) and were more likely to carry at least one copy of APOE ε4 allele (AD: 71.1%, MCI: 46.8%, HC: 28.1%, p < 0.001).