The Frontal Assessment Battery Does Not Differentiate Frontotemporal Dementia from Alzheimer’s Disease

Abstract

Background: An early differentiation of Alzheimer’s disease (AD) from frontotemporal dementia (FTD) is important, since these conditions are essentially different regarding prognosis and therapeutical approach. Until now, no single test is available which allows a reliable differentiation. The Frontal Assessment Battery (FAB) has been found to have good reliability in identifying an executive deficit in frontal syndromes and in extrapyramidal disorders. The ability of the FAB to distinguish AD from FTD in mildly demented patients is less clearly assessed. Methods: We compared FAB scores in a consecutive series of 33 FTD (frontal variant) and 85 AD patients. Results: FAB global scores in the two groups were very similar, also when considering only mildly demented subgroups [Mini Mental State Examination (MMSE) score ≧20; 20 FTD and 38 AD patients]. Considering FAB subscores, only the ‘go-no go’ subtest showed a significant difference, reflecting a poorer inhibitory motor control in AD patients. FAB scores in the two groups of patients correlated with global cognitive decline (MMSE), and with executive and visuospatial test scores, showing good concurrent validity. Conclusion: The FAB does not differentiate patients with AD from those with FTD, like all other executive tests. However, it may be useful in the examination of executive function in AD, FTD and several other pathological conditions.

INECO Frontal Screening (IFS): A brief, sensitive, and specific tool to assess executive functions in dementia – ERRATUM

“…More specifi cally, bvFTD patients exhibited a more severe executive dysfunction, represented by their lower overall IFS scores compared with patients with AD. This difference becomes especially important when considering that the FAB's initially reported discriminant ability failed to be replicated by other research groups (Castiglioni et al, 2006 ;Lipton et al, 2005 ). The more severe executive dysfunction observed in patients with the bvFTD is consistent with the etiological properties of this condition: predominant frontal atrophy and executive disorders since the early stages (Hodges, 2001 ).…”

“…The original authors conclude that the FAB is an easy-to-administer battery, sensitive to frontal dysfunction. By contrast, other studies have cast doubts on the sensitivity and specifi city of the FAB, and in particular, its ability to actually differentiate types of dementia, such as AD and FTD (Castiglioni et al, 2006 ;Lipton et al, 2005 ) in the early stages. Moreover, although the original study by Dubois et al ( 2000) showed no correlation between the FAB and general cognitive measures, subsequent studies failed to replicate these fi ndings suggesting that performance on the FAB does not refl ect frontal function exclusively (Castiglioni et al, 2006 ;Lipton et al, 2005 ).…”

Gray matter network differences between behavioral variant frontotemporal dementia and Alzheimer's disease

“…We did not study the FAB because previous studies show that it does not differentiate bvFTD from AD (Castiglioni et al, 2006). Instead we chose to study associations with impaired functioning in 5 cognitive domains.…”

A short neuropsychologic and cognitive evaluation of frontotemporal dementia

“…However, they are unable to discriminate AD from FTD [32]. Despite the different pattern of brain damage, both groups showed a poor performance on Stroop's and Tower of London tests, secondary to an inhibitory dysfunction related to the disconnection within the network of cerebral areas recruited during the performance of these tests [33,34].…”

“…Although these appear more sensitive than cognitive testing in FTD [31], it also includes cognitive items [18]. The FAB [11] accurately discriminates between patients with frontal lobe dysfunction from normal controls, but the sensitivity and specificity to differentiate FTD from AD are not very high (77% and 87%, respectively) in mildly demented groups [14,32].…”