Can brain scans and eye tests predict Alzheimer's years before symptoms?

Copied word for word from the study's registry entry, so the wording is the study team's rather than ours.

Inclusion Criteria: * Subjects that previously participated in the INSIGHT cohort * Aged 70 to 95 years old * Having signed an informed consent * Willing to and able undergo a baseline PET amyloid imaging * Affiliating to the French health-care system * Having an identified informant who has sufficient contact with the participant and has to be able to provide accurate information, at least by phone, about the participants' cognitive and functional abilities. Exclusion Criteria: * Clinical Dementia Rating ≥1 at screening/baseline visit only * Fulfilling research diagnostic criteria for any type of dementia-related disorder at screening visit (clinical AD, Dementia with Lewy Bodies \[DLB\], fronto-temporal dementia \[FTD\], vascular dementia, chronic traumatic encephalopathy \[CTE\], Limbic-predominant Age-related TDP-43 Encephalopathy \[LATE\], Primary age-related tauopathy \[PART) * Presence of any medical condition associated with a long-term risk of cognitive impairment or dementia including Parkinson's disease, brain tumor, subdural hematoma, vascular malformations, territorial stroke (excluding smaller watershed strokes), chronic hydrocephalus, traumatic brain injury with neurological sequelae, active alcohol/drug abuse, major depressive disorder, schizophrenia and bipolar disorder * Current serious or unstable illnesses (including cardiovascular, hepatic, renal, gastroenterologic, respiratory, endocrinologic or hematologic disease) that might make the subject's participation in an investigational trial unsafe * Any contraindications for MRI/ PET scan procedure (claustrophobia, ferromagnetic object in the body), to FDG or to 18F-Florbetapir (Amyvid®). * Hypersensitivity to the active substance or to any of the excipients of 18F-Florbetapir (Amyvid®). * Participation in any clinical trial of an investigational product in the last 30 days before the screening (during all study duration co-inclusion in other clinical trial of an investigational product or observational research \[biomarker cohort e.g.\] will be possible but the information would need to be recorded). * Unable to comply with protocol requirements in the opinion of the investigator * Being under guardianship (safeguard of justice, curatorship or guardianship) * Residence in skilled nursing facility, including nursing homes (EHPAD).