Comparison of neuropsychological functioning in Alzheimer's disease and frontotemporal dementia

Abstract

Neuropsychological changes distinguishing mild Alzheimer's disease (AD) from frontotemporal dementia (FTD) have been described, but empirical verification of differential cognitive characteristics is lacking. Archival neuropsychological data on 15 FTD patients, 16 AD patients, and 16 controls were compared. Controls outperformed both patient groups on measures of verbal and nonverbal memory, executive ability, and constructional skill, with AD patients showing more widespread memory decline. No differences were found between the 3 groups in confrontation naming, recognition memory, or basic attention. Patient groups differed only •n nonverbal memory, with FTD patients performing significantly better than AD patients. However, patient groups also differed in pattern of performance across executive and memory domains. Specifically, AD patients exhibited significantly greater impairment on memory than executive tasks, whereas the opposite pattern characterized the rTD group. These findings suggest that examination of relative rankings of scores across cognitive domains, in addition to interpretation of individual neuropsychological scores, may be useful in differential diagnosis of FTD versus AD. (JINS, 1996, 2, 505-510.)

Distinct cognitive profiles and rates of decline on the Mattis Dementia Rating Scale in autopsy-confirmed frontotemporal dementia and Alzheimer's disease

“…The profiles of cognitive deficits exhibited by FTD and AD patients on the MDRS parallel those seen with more extensive testing. Several studies have shown greater memory impairment in AD than in FTD for both verbal (Elfgren et al, 1994;Kramer et al, 2003;Lindau et al, 1998;Perry & Hodges, 2000;Rosen et al, 2004;Thomas-Anterion et al, 2000) and visual (Frisoni et al, 1995;Kertesz et al, 2003a;Kramer et al, 2003;Pachana et al, 1996;Perry & Hodges, 2000) materials, a finding that has been attributed to greater medial temporolimbic pathology in AD (Braak & Braak, 1991) than in FTD (Frisoni et al, 1996;Lavenu et al, 1998). Similarly, a larger deficit in conceptual abilities in FTD than in AD has been shown on tests of conceptual processing and verbal abstraction (Kertesz et al, 2003a;Slachevsky et al, 2004).…”

“…It should be noted that studies of visuospatial and constructional abilities that have not shown a difference between FTD and AD often involve drawing the Rey-Osterrieth Complex Figure (Diehl et al, 2005;Frisoni et al, 1995;Kertesz et al, 2003a;Kramer et al, 2003;Pachana et al, 1996;Rosen et al, 2004), a task known to be influenced by attentional and strategicorganizational requirements dependent upon the frontal lobes (Varma et al, 1999). A second major finding from the present study is that FTD patients exhibit a faster rate of cognitive decline than those with AD when cognition is measured by the MDRS.…”

“…Accurate differential diagnosis is crucial, however, given potential differences in prognosis (Rascovsky et al, 2005) and in pharmacological management strategies that might be suggested by different neurotransmitter system involvement in the two disorders Moretti et al, 2003;Pasquier et al, 2003;Qume et al, 1994;Rahman et al, 1999;Sparks & Markesbery, 1991;Swartz et al, 1997). Recent studies using batteries of neuropsychological tests suggest that FTD and AD are associated with distinct cognitive profiles that might aid in their differential diagnosis (Binetti et al, 2000;Elfgren et al, 1994;Frisoni et al, 1995;Gregory et al, 1997;Kramer et al, 2003;Lindau et al, 1998;Mendez et al, 1996;Pachana et al, 1996;Rascovsky et al, 2002;Thomas-Anterion et al, 2000). Particularly compelling are retrospective studies that have shown a double dissociation in which mildly-to-moderately demented patients with autopsy-confirmed FTD are more impaired than those with autopsy-confirmed AD on tests sensitive to frontal lobe dysfunction (e.g., word generation tasks), but less impaired on tests of memory and visuospatial abilities sensitive to dysfunction of medial temporal and parietal association cortices (e.g., Rascovsky et al, 2002).…”

The Early Neuropsychological and Behavioral Characteristics of Frontotemporal Dementia

“…Pachana et al (1996), for example, noted that FTD patients were relatively more impaired on executive tasks and relatively less impaired in memory that AD patients, and Kramer et al (2003) reported that the relative patterns of impairment on executive, language, and memory measures were more discriminating than any individual test.…”

Clinical Value of Constructional Skill Testing in Patients With Secondary Normal Pressure Hydrocephalus -Two Case Reports-

“…2,5,6,11,[14][15][16] Patients with Alzheimer's disease and frontotemporal dementia do not have significant problems with constructional skill because their parietal regions remain intact. 3,4,8) However, few reports have investigated the effect of NPH on constructional skill, although the parietal regions are also affected.…”