Pierre Chapuis, Presenter: Nothing to Disclose

Mathilde Sauvee, Abstract Co-Author: Nothing to Disclose

Maud Medici MSc, Abstract Co-Author: Nothing to Disclose

Amelie Serra, Abstract Co-Author: Nothing to Disclose

Eldda Banciu MD, Abstract Co-Author: Nothing to Disclose

Alexandre Moreau-Gaudry MD, PhD, Abstract Co-Author: Nothing to Disclose

Olivier Moreaud, Abstract Co-Author: Nothing to Disclose

Alexandre Krainik MD, PhD, Abstract Co-Author: Nothing to Disclose

Our objectives were: 1) to identify morphological subgroups on patients suffering from Alzheimer's disease (AD) or mild cognitive impairment (MCI); 2) to characterize neuropsychological profiles of each subgroup.

145 patients referred for AD (NIA-AA criteria), either at the stage of dementia or MCI-a were examined using structural MRI. All examinations were blindly reviewed twice by 3 radiologists and 2 neurologists. We rated microangiopathy (simplified Fazekas’s scale: 0-3), hippocampal atrophy (Scheltens’s score: 0-4), parietal atrophy (Koedam’s scale : 0-3), and the Gradient of Fronto-Parietal Atrophy (GFPA: -2 to +3). A Multiple Component Analysis (MCA) followed by a hierarchical ascending classification were conducted to identify morphologically distinct subgroups. Among these, 76 patients completed all the neuropsychological tests. Univariate and multivariate analyses were further conducted on these data across morphological subgroups.

Inter- and intraraters agreements were excellent and very good for microangiopathy and hippocampal atrophy ratings. They were higher for GFPA than for Koedam’s. MCA without priors identified 3 groups: Group 1 was characterized by no/discrete microangiopathy (Fazekas≤1), severe hippocampal atrophy (Scheltens=4), severe parietal atrophy (GFPA≥2; Koedam≥2); Group 2 had significant microangiopathy (Fazekas≥2), severe hippocampal atrophy (Scheltens=3), no parietal atrophy (GFPA≤0; Koedam≤1); Group 3 had a mild hippocampal atrophy (Scheltens ≤ 2) and a mild parietal atrophy (GFPA=1; Koedam<2). In Group 1 and contrary to Group 2, executive functions and the backward digit span related to working memory profile were preserved (p=0.01). Group 3 had working memory impairment, only.

Combined characterization of microangiopathy, hippocampal, parietal, and gradient of fronto-parietal atrophy allows to identify morphological subgroups among patients referred for AD and at risk. These subgroups have neuropsychological differences. These results may suggest different pathophysiological mechanisms.

Besides hippocampal atrophy, patients referred for MCI-a and AD may harbor parietal disorders. Among these patients, a better structural and neuropsychological characterization help to identify subgroups, which could be specific targets for new therapies.

Chapuis, P, Sauvee, M, Medici, M, Serra, A, Banciu, E, Moreau-Gaudry, A, Moreaud, O, Krainik, A, Morphological and Neuropsychological Profiles in Patients with Alzheimer's Disease.  Radiological Society of North America 2014 Scientific Assembly and Annual Meeting, - ,Chicago IL. http://archive.rsna.org/2014/14015207.html