%0 Journal Article %J J Alzheimers Dis %D 2016 %T Comparison of Prefrontal Atrophy and Episodic Memory Performance in Dysexecutive Alzheimer's Disease and Behavioral-Variant Frontotemporal Dementia. %A Wong, Stephanie %A Bertoux, Maxime %A Savage, Greg %A Hodges, John R %A Piguet, Olivier %A Hornberger, Michael %K Aged %K Alzheimer Disease %K Atrophy %K Databases, Factual %K Diagnosis, Differential %K Executive Function %K Female %K Frontotemporal Dementia %K Hippocampus %K Humans %K Image Processing, Computer-Assisted %K Magnetic Resonance Imaging %K Male %K Memory, Episodic %K Middle Aged %K Neuropsychological Tests %K Prefrontal Cortex %X

Alzheimer's disease (AD) sometimes presents with prominent executive dysfunction and associated prefrontal cortex atrophy. The impact of such executive deficits on episodic memory performance as well as their neural correlates in AD, however, remains unclear. The aim of the current study was to investigate episodic memory and brain atrophy in AD patients with relatively spared executive functioning (SEF-AD; n = 12) and AD patients with relatively impaired executive functioning (IEF-AD; n = 23). We also compared the AD subgroups with a group of behavioral-variant frontotemporal dementia patients (bvFTD; n = 22), who typically exhibit significant executive deficits, and age-matched healthy controls (n = 38). On cognitive testing, the three patient groups showed comparable memory profiles on standard episodic memory tests, with significant impairment relative to controls. Voxel-based morphometry analyses revealed extensive prefrontal and medial temporal lobe atrophy in IEF-AD and bvFTD, whereas this was limited to the middle frontal gyrus and hippocampus in SEF-AD. Moreover, the additional prefrontal atrophy in IEF-AD and bvFTD correlated with memory performance, whereas this was not the case for SEF-AD. These findings indicate that IEF-AD patients show prefrontal atrophy in regions similar to bvFTD, and suggest that this contributes to episodic memory performance. This has implications for the differential diagnosis of bvFTD and subtypes of AD.

%B J Alzheimers Dis %V 51 %P 889-903 %8 2016 %G eng %N 3 %1 http://www.ncbi.nlm.nih.gov/pubmed/26923025?dopt=Abstract %R 10.3233/JAD-151016 %0 Journal Article %J J Alzheimers Dis %D 2016 %T Social Cognition Deficits: The Key to Discriminate Behavioral Variant Frontotemporal Dementia from Alzheimer's Disease Regardless of Amnesia? %A Bertoux, Maxime %A de Souza, Leonardo Cruz %A O'Callaghan, Claire %A Greve, Andrea %A Sarazin, Marie %A Dubois, Bruno %A Hornberger, Michael %K Aged %K Alzheimer Disease %K Amnesia %K Cognition %K Diagnosis, Differential %K Emotions %K Female %K Frontotemporal Dementia %K Humans %K Male %K Memory, Episodic %K Neuropsychological Tests %K Social Perception %X

Relative sparing of episodic memory is a diagnostic criterion of behavioral variant frontotemporal dementia (bvFTD). However, increasing evidence suggests that bvFTD patients can show episodic memory deficits at a similar level as Alzheimer's disease (AD). Social cognition tasks have been proposed to distinguish bvFTD, but no study to date has explored the utility of such tasks for the diagnosis of amnestic bvFTD. Here, we contrasted social cognition performance of amnestic and non-amnestic bvFTD from AD, with a subgroup having confirmed in vivo pathology markers. Ninety-six participants (38 bvFTD and 28 AD patients as well as 30 controls) performed the short Social-cognition and Emotional Assessment (mini-SEA). BvFTD patients were divided into amnestic versus non-amnestic presentation using the validated Free and Cued Selective Reminding Test (FCSRT) assessing episodic memory. As expected, the accuracy of the FCSRT to distinguish the overall bvFTD group from AD was low (69.7% ) with ∼50% of bvFTD patients being amnestic. By contrast, the diagnostic accuracy of the mini-SEA was high (87.9% ). When bvFTD patients were split on the level of amnesia, mini-SEA diagnostic accuracy remained high (85.1% ) for amnestic bvFTD versus AD and increased to very high (93.9% ) for non-amnestic bvFTD versus AD. Social cognition deficits can distinguish bvFTD and AD regardless of amnesia to a high degree and provide a simple way to distinguish both diseases at presentation. These findings have clear implications for the diagnostic criteria of bvFTD. They suggest that the emphasis should be on social cognition deficits with episodic memory deficits not being a helpful diagnostic criterion in bvFTD.

%B J Alzheimers Dis %V 49 %P 1065-74 %8 2016 %G eng %N 4 %1 http://www.ncbi.nlm.nih.gov/pubmed/26756325?dopt=Abstract %R 10.3233/JAD-150686