The prevalence of dementia in this study was higher than in other studies, particularly among younger elderly.

It has been challenging to identify clinical cognitive markers that can differentiate patients with Alzheimer's disease (AD) from those with behavioral variant frontotemporal dementia (bvFTD). The short-term memory binding (STMB) test assesses the ability to integrate colors and shapes into unified representations and to hold them temporarily during online performance. The objective of this study is to investigate whether free recall deficits during short-term memory binding (STMB) test can differentiate patients with AD from those with bvFTD and controls. Participants were 32 cognitively intact adults, 35 individuals with AD and 18 with bvFTD. All patients were in the mild dementia stage. Receiver-operating characteristic (ROC) analyses were used to examine the diagnostic accuracy of the STMB. The results showed that AD patients performed significantly worse than controls and bvFTD patients in the STMB test, while the latter groups showed equivalent performance. The bound condition of the STMB test showed an AUC of 0.853, with 84.4% of sensitivity and 80% of specificity to discriminate AD from controls and an AUC of 0.794, with 72.2% of sensitivity and 80% of specificity to differentiate AD from bvFTD. Binding deficits seem specific to AD. The free recall version of the STMB test can be used for clinical purposes and may aid in the differential diagnosis of AD. Findings support the view that the STMB may be a suitable cognitive marker for AD.

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Introduction: There is a shortage of validated instruments to estimate disease progression in frontotemporal dementia (FTD). Objectives: To evaluate the ability of the FTD Rating Scale (FTD-FRS) to detect functional and behavioral changes in patients diagnosed with the behavioral variant of FTD (bvFTD), primary progressive aphasia (PPA), and Alzheimer disease (AD) after 12 months of the initial evaluation, compared to the Clinical Dementia Rating scale−frontotemporal lobar degeneration (CDR-FTLD) and the original Clinical Dementia Rating scale (CDR). Methods: The sample consisted of 70 individuals, aged 40+ years, with at least 2 years of schooling, 31 with the diagnosis of bvFTD, 12 with PPA (8 with semantic variant and 4 with non-fluent variant), and 27 with AD. The FTD-FRS, the CDR, and the 2 additional CDR-FTLD items were completed by a clinician, based on the information provided by the caregiver with frequent contact with the patient. The Addenbrooke Cognitive Examination-Revised was completed by patients. After 12 months, the same protocol was applied. Results: The FTD-FRS, CDR-FTLD, and CDR detected significant decline after 12 months in the 3 clinical groups (exception: FTD-FRS for PPA). The CDR was less sensitive to severe disease stages. Conclusions: The FTD-FRS and the CDR-FTLD are especially useful tools for dementia staging in AD and in the FTD spectrum.

The present study suggested that the IFS may be used to screen for executive dysfunction in dementia. Nonetheless, it should be used with caution in the differential diagnosis between AD and bvFTD.

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Objectives It has been challenging to identify cognitive markers to differentiate healthy brain aging from neurodegeneration due to Alzheimer’s disease (AD) that are not affected by age and education. The Short-Term Memory Binding (STMB) showed not to be affected by age or education when using the change detection paradigm. However, no previous study has tested the effect of age and education using the free recall paradigm of the STMB. Therefore, the objective of this study was to investigate age and education effects on the free recall version of the STMB test under different memory loads. Methods 126 healthy volunteers completed the free recall STMB test. The sample was divided into five age bands and into five education bands for comparisons. The STMB test assessed free recall of two (or three) common objects and two (or three) primary colors presented as individual features (unbound) or integrated into unified objects (bound). Results The binding condition and the larger set size generated lower free recall scores. Performance was lower in older and less educated participants. Critically, neither age nor education modified these effects when compared across experimental conditions (unbound v. bound features). Conclusions Binding in short-term memory carries a cost in performance. Age and education do not affect such a binding cost within a memory recall paradigm. These findings suggest that this paradigm is a suitable cognitive marker to differentiate healthy brain aging from age-related disease such as AD.

The present study is the first to document the factorial structure of the FTD-FRS and its convergent validity with the CDR-FTLD. These tools are key to determine dementia severity in FTD. The Brazilian FTD-FRS demonstrated adequate psychometric properties for use in Brazil. This instrument may contribute to disease staging in FTD and may help to document intervention-related changes.