First, prescribers will have to take into account the well-established risk factors for amyloid-related imaging abnormalities (ARIA) (i.e., ApoE ε4 status, MRI signs of cerebral amyloid angiopathy, cerebrovascular disease, dosage, and pharmacodynamic properties of an anti-Aβ mAb) [4, 31], but also the possible comorbidities (i.e., medical conditions other than AD, such as non-AD neurological disorders, bleeding disorders and antithrombotic therapy, cardiovascular diseases, history of recent cancer, renal or liver dysfunction, etc.). This evidence concerns the gene APOE and Alzheimer disease.