Neuroimaging Markers of Alzheimer Disease: a Longitudinal Population Study

Overview

It is now acknowledged that Alzheimer's disease is characterized by a long period of pathophysiological change. Developing new strategies to achieve diagnoses as early as possible has become a major goal for therapies aimed at slowing the progression of this disease. While diagnoses currently rely principally on clinical neuropsychology, the typical diagnostic criteria of NINCDS-ADRDA are inapplicable in the early stage of the disease. The goal of our project is to identify very early imaging markers for Alzheimer's disease among patients with no report of cognitive difficulties. In order to achieve this goal, we propose a longitudinal study in an elderly population cohort.

The AMImage2 project that follows AMImage1 and MRI-3C consists of an imaging study in association with longitudinal epidemiologic cohorts (AMI and 3C). The first objective is to investigate the association between the evolution of imaging markers and the evolution of cognitive performance in normal and pathological aging. This objective will be conducted among subjects having already participated in AMImage1, thereby permitting the longitudinal study of MRI data. An MRI exam will also be proposed to 100 subjects (members of the AMI and 3C cohorts) in order to provide a third wave of MRI (for a longer-term MRI follow-up) or a second one for the participants who only had one MRI exam in the AMImage project. Our second objective is cross-sectional and will study the imaging parameters of subjects presenting signs of cognitive decline over the previous 4 years (through the follow-up conducted in the AMI cohort). Finally, an additional objective will consist in a comparison between two populations very contrasted in terms of cognitive reserve: AMI (very low education level in rural area) and 3C (higher level of education in urban area).