Normative data for the Brief Cognitive Screening Battery stratified by age and education

Probable 4-Repeat Tauopathy Criteria Predict Brain Amyloid Negativity, Distinct Clinical Features, and FDG-PET/MRI Neurodegeneneration Patterns in Corticobasal Syndrome

BACKGROUND

Corticobasal syndrome (CBS) is associated with diverse underlying pathologies, including the four-repeat (4R)-tauopathies. The Movement Disorders Society (MDS) criteria for progressive supranuclear palsy (PSP) proposed the novel category "probable 4R-tauopathy" to address the phenotypic overlap between PSP and corticobasal degeneration (CBD).

OBJECTIVES

To investigate the clinical ability of the MDS-PSP criteria for probable 4R-tauopathy in predicting a negative amyloid-PET in CBS. Additionally, this study aims to explore CBS patients classified as 4R-tauopathy concerning their clinical features and neuroimaging degeneration patterns.

METHODS

Thirty-two patients with probable CBS were prospectively evaluated and split into those who fulfilled or did not fulfill the 4R-tauopathy criteria (CBS-4RT+ vs. CBS-4RT-). All patients underwent positron emission tomographies (PET) with [18 F]fluorodeoxyglucose and [11 C]Pittsburgh Compound-B (PIB) on a hybrid PET-MRI scanner to perform multimodal quantitative comparisons with a control group.

RESULTS

Eleven patients were clinically classified as CBS-4RT+, and only one had a positive PIB-PET. The CBS-4RT+ classification had 92% specificity, 52% sensitivity, and 69% accuracy in predicting a negative PIB-PET. The CBS-4RT+ group presented with dysarthria and perseveration more often than the CBS-4RT- group. Moreover, the CBS-4RT+ group showed a prominent frontal hypometabolism extending to the supplementary motor area and striatum, and brain atrophy at the anterior cingulate and bilateral striata.

CONCLUSIONS

The 4R-tauopathy criteria were highly specific in predicting a negative amyloid-PET in CBS. Patients classified as 4R-tauopathy presented distinct clinical aspects, as well as brain metabolism and atrophy patterns previously associated with tauopathies.

Modified Brief Cognitive Screening Battery - Indonesian Version: cross-cultural adaptation and normative data based on demographic factors in North Sumatra, Indonesia

Introduction

Key component of early detection of dementia is a brief and culturally appropriate cognitive screening tool. This study aimed to perform a cultural adaptation of the Brief Cognitive Screening Battery (BCSB) and to obtain normative data from the older adult population.

Methods

Cross-cultural adaptation process to develop BCSB-INA was performed. This was followed by a feasibility study from community dwelling older adults from several urban and rural areas in North Sumatra, Indonesia.

Results

The BCSB-INA was generally well understood and showed not much discrepancy in translation from the original version. There were differences in semantic and phonemic fluency and CDT based on years of education, but no difference was found on other domain, including the delayed recall of the FMT. The battery was more influenced by age than education.

Discussion

The BCSB-INA is culturally appropriate and feasible to be used in population with heterogenous educational background in Indonesia.

Cognitive evaluation in Parkinson's disease: applying the Movement Disorder Society recommendations in a population with a low level of formal education

BACKGROUND

 The diagnosis of cognitive disorders in Parkinson disease (PD) can be very challenging. Aiming at establishing uniform and reliable diagnostic procedures, the International Parkinson's Disease and Movement Disorder Society (MDS) commissioned task forces to delineate diagnostic criteria for mild cognitive impairment (MCI) and dementia in PD.

OBJECTIVES

 To investigate the applicability of the MDS recommendations for cognitive evaluation in a Brazilian sample of patients with PD with low levels of formal education.

METHODS

 A total of 41 patients with PD were subjected to a comprehensive neuropsychological evaluation based on tests proposed by the MDS, which included the Mini-Mental State Examination, the Mattis Dementia Rating Scale (MDRS), the Trail Making Test (TMT) parts A and B, in addition to language and memory skills assessment. Neuropsychiatric and daily functioning features were also evaluated. Spearman correlation analyses were used to evaluate the association between the scores obtained in the cognitive scales and demographic/clinical variables.

RESULTS

 Although none of the participants had a formal diagnosis of dementia, 50% presented some degree of cognitive impairment when considering the results of the MDRS. Of note, a noticeable number of patients was not able to complete the full neuropsychological assessment. The TMT part B was the most difficult task, being completed by only 22 participants (54%). As expected, the greater the educational level, the better the performance on the cognitive tests. Better motor function was also associated with better scores in cognition.

CONCLUSIONS

 Adopting strict inclusion/exclusion criteria and a comprehensive clinical evaluation, we found remarkable limitations for the MDS recommendations when individuals with low educational levels are considered. A revision of the current guidelines is necessary considering differences among populations, especially related to formal education.

Diagnóstico da demência frontotemporal: recomendações do Departamento Científico de Neurologia Cognitiva e do Envelhecimento da Academia Brasileira de Neurologia

RESUMO A “demência frontotemporal” (DFT) é uma síndrome clínica, cujo denominador comum é o acometimento focal dos lobos frontais e/ou temporais. A DFT tem três fenótipos clínicos distintos: a variante comportamental e dois subtipos linguísticos, a saber, a afasia progressiva primária não-fluente/agramática (APP-NF/A) e a afasia progressiva primária semântica (APP-S). A DFT é a segunda causa mais comum de demência em indivíduos com idade inferior a 65 anos, após a doença de Alzheimer. O presente artigo apresenta recomendações para diagnóstico da DFT no cenário brasileiro, considerando os três níveis de complexidade do sistema de saúde: atenção primária à saúde e níveis secundários. São propostos protocolos de investigação diagnóstica abrangendo testagem cognitiva, avaliação comportamental, avaliação fonoaudiológica, exames laboratoriais e de neuroimagem.

Subjective cognitive decline, mild cognitive impairment, and dementia - syndromic approach: recommendations of the Scientific Department of Cognitive Neurology and Aging of the Brazilian Academy of Neurology

ABSTRACT This consensus, performed by the Brazilian Academy of Neurology (BAN) will approach practically how to evaluate patients with cognitive complaints and how to clinically and etiologically diagnose the three clinical syndromes associated with the different stages of cognitive decline: subjective cognitive decline (SCD), mild cognitive impairment (MCI), and dementia. This BAN consensus discusses SCD diagnosis for the first time, updates MCI and dementia diagnoses, recommends the adequate cognitive tests and the relevant etiological work-up and care of patients with cognitive decline at different levels of care within the Brazilian Unified Health System. We also review the main assessment instruments used in Brazil and Latin America.

Declínio cognitivo subjetivo, comprometimento cognitivo leve e demência - diagnóstico sindrômico: recomendações do Departamento Científico de Neurologia Cognitiva e do Envelhecimento da Academia Brasileira de Neurologia

RESUMO Este consenso realizado pela Academia Brasileira de Neurologia (ABN) abordará de maneira prática como avaliar pacientes com queixas cognitivas e como realizar o diagnóstico clínico e etiológico das três síndromes clínicas associadas aos estágios de declínio cognitivo: declínio cognitivo subjetivo (DCS), comprometimento cognitivo leve (CCL) e demência. O diagnóstico de DCS é discutido pela primeira vez em consenso da ABN e as atualizações para o diagnóstico de CCL e demência são abordadas, bem como a recomendação para o uso de testes cognitivos apropriados, investigação etiológica pertinente e cuidados aos pacientes com declínio cognitivo nos diferentes níveis de atenção do Sistema Único de Saúde. Foi realizada pesquisa dos principais instrumentos de avaliação utilizados em nosso meio e na América Latina.

Diagnosis of frontotemporal dementia: recommendations of the Scientific Department of Cognitive Neurology and Aging of the Brazilian Academy of Neurology

ABSTRACT “Frontotemporal dementia” (FTD) is a clinical syndrome characterized by the focal involvement of the frontal and/or temporal lobes. FTD has three clinical phenotypes: the behavioral variant and two linguistic subtypes, namely, non-fluent/agrammatic primary progressive aphasia (PPA-NF/A) and semantic PPA (PPA-S). FTD is the second most common cause of dementia in individuals under the age of 65 years. This article presents recommendations for the diagnosis of FTD in the Brazilian scenario, considering the three levels of complexity of the health system: primary health care, secondary and tertiary levels. Diagnostic guidelines are proposed, including cognitive testing, behavioral and language assessments, laboratory tests, and neuroimaging.

Neuropsychological Assessment in Dementia Diagnosis

PURPOSE OF REVIEW

This article discusses the application of neuropsychological evaluation to the workup of individuals with age-related cognitive impairment and suspected dementia. Referral questions, principles of evaluation, and common instruments to detect abnormalities in cognition and behavior in this population are reviewed. The integration of neuropsychological test findings with other clinical and biomarker information enhances early detection, differential diagnosis, and care planning.

RECENT FINDINGS

Life expectancy is increasing in the United States, and, accordingly, the prevalence and incidence of dementia associated with age-related neurodegenerative brain disease are rising. Age is the greatest risk factor for the dementia associated with Alzheimer disease, the most common neurodegenerative cause of dementia in people over 65 years of age; other etiologies, such as the class of frontotemporal lobar degenerations, are increasingly recognized in individuals both younger and older than 65 years of age. The clinical dementia diagnosis, unfortunately, is imperfectly related to disease etiology; however, probabilistic relationships can aid in diagnosis. Further, mounting evidence from postmortem brain autopsies points to multiple etiologies. The case examples in this article illustrate how the neuropsychological evaluation increases diagnostic accuracy and, most important, identifies salient cognitive and behavioral symptoms to target for nonpharmacologic intervention and caregiver education and support. Sharing the diagnosis with affected individuals is also discussed with reference to prognosis and severity of illness.

SUMMARY

The clinical neuropsychological examination facilitates early detection of dementia, characterizes the level of severity, defines salient clinical features, aids in differential diagnosis, and points to a pathway for care planning and disease education.

Different patterns of gray matter atrophy in behavioral variant frontotemporal dementia with and without episodic memory impairment

BACKGROUND

Differentiating patients with behavioral variant frontotemporal dementia (bvFTD) from Alzheimer's disease (AD) is important as these two conditions have distinct treatment and prognosis. Using episodic impairment and medial temporal lobe atrophy as a tool to make this distinction has been debatable in the recent literature, as some patients with bvFTD can also have episodic memory impairment and medial temporal lobe atrophy early in the disease.

OBJECTIVES

To compare brain atrophy patterns of patients with bvFTD with and without episodic memory impairment to that of patients with AD.

METHODS

We analyzed 19 patients with bvFTD, 21 with AD and 21 controls, matched by age, sex, and years of education. They underwent brain MRI and the memory test from the Brief Cognitive Battery (BCB) to assess episodic memory. We then categorized the bvFTD group into amnestic (BCB delayed recall score <7) and non-amnestic.

RESULTS

The amnestic bvFTD group (n = 8) had significant gray matter atrophy in the left parahippocampal gyrus, right cingulate and precuneus regions compared with the nonamnestic group. Compared with AD, amnestic bvFTD had more atrophy in the left fusiform cortex, left insula, left inferior temporal gyrus and right temporal pole, whereas patients with AD had more atrophy in the left hippocampus, left frontal pole and left angular gyrus.

CONCLUSIONS

There is a group of amnestic bvFTD patients with episodic memory dysfunction and significant atrophy in medial temporal structures, which poses a challenge in considering only these features when differentiating bvFTD from AD clinically.

Accuracy of the Brief Cognitive Screening Battery for diagnosing Alzheimer's disease defined by cerebrospinal fluid biomarkers and AT(N) classification: a case-control study

BACKGROUND

Validation of cognitive instruments for detection of Alzheimer's disease (AD) based on correlation with diagnostic biomarkers allows more reliable identification of the disease.

OBJECTIVES

To investigate the accuracy of the Brief Cognitive Screening Battery (BCSB) in the differential diagnosis between AD, non-AD cognitive impairment (both defined by cerebrospinal fluid [CSF] biomarkers) and healthy cognition, and to correlate CSF biomarker results with cognitive performance.

METHODS

Overall, 117 individuals were evaluated: 45 patients with mild cognitive impairment (MCI) or mild dementia within the AD continuum defined by the AT(N) classification [A+T+/-(N)+/]; 27 non-AD patients with MCI or mild dementia [A-T+/-(N)+/-]; and 45 cognitively healthy individuals without CSF biomarker results. All participants underwent evaluation using the BCSB.

RESULTS

The total BCSB and delayed recall (DR) scores of the BCSB memory test showed high diagnostic accuracy, as indicated by areas under the ROC curve (AUC): 0.89 and 0.87, respectively, for discrimination between AD and non-AD versus cognitively healthy controls. Similarly, total BCSB and DR displayed high accuracy (AUC-ROC curves of 0.89 and 0.91, respectively) for differentiation between AD and controls. BCSB tests displayed low accuracy for differentiation between AD and non-AD. The CSF levels of biomarkers correlated significantly, though weakly, with DR.

CONCLUSIONS

Total BCSB and DR scores presented good accuracy for differentiation between patients with a biological AD diagnosis and cognitively healthy individuals, but low accuracy for differentiating AD from non-AD patients.

Metabolic and Structural Signatures of Speech and Language Impairment in Corticobasal Syndrome: A Multimodal PET/MRI Study

Introduction: Corticobasal syndrome (CBS) is a progressive neurological disorder related to multiple underlying pathologies, including four-repeat tauopathies, such as corticobasal degeneration and progressive supranuclear palsy, and Alzheimer's disease (AD). Speech and language are commonly impaired, encompassing a broad spectrum of deficits. We aimed to investigate CBS speech and language impairment patterns in light of a multimodal imaging approach.

Materials and Methods: Thirty-one patients with probable CBS were prospectively evaluated concerning their speech–language, cognitive, and motor profiles. They underwent positron emission tomography with [¹⁸F]fluorodeoxyglucose (FDG-PET) and [¹¹C]Pittsburgh Compound-B (PIB-PET) on a hybrid PET-MRI machine to assess their amyloid status. PIB-PET images were classified based on visual and semi-quantitative analyses. Quantitative group analyses were performed on FDG-PET data, and atrophy patterns on MRI were investigated using voxel-based morphometry (VBM). Thirty healthy participants were recruited as imaging controls.

Results: Aphasia was the second most prominent cognitive impairment, presented in 67.7% of the cases, following apraxia (96.8%). We identified a wide linguistic profile, ranging from nonfluent variant-primary progressive aphasia to lexical–semantic deficits, mostly with impaired verbal fluency. PIB-PET was classified as negative (CBS-A– group) in 18/31 (58%) and positive (CBS-A+ group) in 13/31 (42%) patients. The frequency of dysarthria was significantly higher in the CBS-A– group than in the CBS-A+ group (55.6 vs. 7.7%, p = 0.008). CBS patients with dysarthria had a left-sided hypometabolism at frontal regions, with a major cluster at the left inferior frontal gyrus and premotor cortex. They showed brain atrophy mainly at the opercular frontal gyrus and putamen. There was a positive correlation between [¹⁸F]FDG uptake and semantic verbal fluency at the left inferior (p = 0.006, R² = 0.2326), middle (0.0054, R² = 0.2376), and superior temporal gyri (p = 0.0066, R² = 0.2276). Relative to the phonemic verbal fluency, we found a positive correlation at the left frontal opercular gyrus (p = 0.0003, R² = 0.3685), the inferior (p = 0.0004, R² = 0.3537), and the middle temporal gyri (p = 0.0001, R² = 0.3993).

Discussion: In the spectrum of language impairment profile, dysarthria might be helpful to distinguish CBS patients not related to AD. Metabolic and structural signatures depicted from this feature provide further insights into the motor speech production network and are also helpful to differentiate CBS variants.

Screening for cognitive impairment among individuals aged 60 years or over: scoping review

BACKGROUND

Growth in aging of the population has led to increasing numbers of elderly people presenting cognitive impairment and evolution to dementia. There is still no consensus within primary care on the best strategy for screening for cognitive impairment among elderly people. Standardization of a simple but reasonably accurate instrument for a brief cognitive test, in primary care environments, would enable healthcare professionals to identify individuals who require a more in-depth assessment of cognition.

OBJECTIVES

To investigate the instruments used by healthcare professionals in studies conducted worldwide and ascertain the most suitable instruments for screening for cognitive impairment among individuals aged 60 years or over, in the Brazilian population.

DESIGN AND SETTING

Scoping review developed at Pontifícia Universidade Católica de São Paulo, Brazil.

METHOD

A systematic search of the literature was conducted for primary studies using instruments to screen for cognitive impairment among individuals aged 60 years or over, in the MEDLINE, EMBASE, Cochrane Central and LILACS databases.

RESULTS

A total of 983 articles were identified by two independent reviewers, from which 49 were selected for full-text reading, based on the criteria defined for this review. From this, 16 articles adhering to the theme of screening for cognitive impairment among the elderly were selected for in-depth analysis.

CONCLUSION

The Mini-Mental State Examination was the instrument most cited in these studies. The Pfeffer Functional Activities Questionnaire and the Verbal Fluency Test (semantic category) present characteristics favoring further studies, for testing as screening instruments for cognitive impairment among elderly people in Brazil.

Papez Circuit Gray Matter and Episodic Memory in Amyotrophic Lateral Sclerosis and Behavioural Variant Frontotemporal Dementia

Amyotrophic lateral sclerosis and behavioural variant frontotemporal dementia are two different diseases recognized to overlap at clinical, pathological and genetic characteristics. Both conditions are traditionally known for relative sparing of episodic memory. However, recent studies have disputed that with the report of patients presenting with marked episodic memory impairment. Besides that, structural and functional changes in temporal lobe regions responsible for episodic memory processing are often detected in neuroimaging studies of both conditions. In this study, we investigated the gray matter features associated with the Papez circuit in amyotrophic lateral sclerosis, behavioural variant frontotemporal dementia and healthy controls to further explore similarities and differences between the two conditions. Our non-demented amyotrophic lateral sclerosis patients showed no episodic memory deficits measured by a short-term delayed recall test while no changes in gray matter of the Papez circuit were found. Compared with the amyotrophic lateral sclerosis group, the behavioural variant frontotemporal dementia group had lower performance on the short-term delayed recall test and marked atrophy in gray matter of the Papez circuit. Bilateral atrophy of entorhinal cortex and mammillary bodies distinguished behavioural variant frontotemporal dementia from amyotrophic lateral sclerosis patients as well as atrophy in left cingulate, left hippocampus and right parahippocampal gyrus. Taken together, our results suggest that sub-regions of the Papez circuit could be differently affected in amyotrophic lateral sclerosis and behavioural variant frontotemporal dementia.

The Figure Memory Test: diagnosis of memory impairment in populations with heterogeneous educational background

Diagnosis of cognitive impairment is usually difficult in low-educated individuals. The Brief Cognitive Screening Battery (BCSB) was designed as a screening tool for the evaluation of cognitive impairment in low-educated individuals, but it may also be used for evaluating individuals with high educational level.

OBJECTIVES

To perform a narrative review analyzing the origin of the BCSB, to report all studies that have used the Figure Memory Test (FMT) of the BCSB, and to demonstrate that it is a useful battery for regions where populations have heterogeneous educational background.

METHODS

We performed a search in PubMed, SciELO, and LILACS using the terms "Brief Cognitive Screening Battery" and "Brief Cognitive Battery".

RESULTS

We obtained 49 papers from PubMed, 32 from SciELO, and 28 from LILACS. After the exclusion of duplicate papers, 54 publications were obtained; five more studies were included from previous knowledge of the authors. Twenty-four papers were related to the impact of education on performance, diagnostic accuracy, cutoff scores and normative studies. The delayed recall of the FMT showed the best accuracy for the diagnosis of dementia with a cutoff score of ≤5 in different education levels. In 35 papers, the FMT of the BCSB was used in clinical studies with different settings, from outpatient memory clinics to epidemiological studies and evaluation of Amazon river basin dwelling individuals, and it was always considered to be easy to apply.

CONCLUSIONS

The FMT of the BCSB is an easy and short tool for the diagnosis of dementia in populations with heterogeneous educational background.

Memory complaints at primary care in a middle-income country: clinical and neuropsychological characterization

There are different causes of memory complaints in the elderly, such as subjective cognitive decline (SCD), mild cognitive impairment (MCI) or dementia.

FDG-PET Patterns Predict Amyloid Deposition and Clinical Profile in Corticobasal Syndrome

BACKGROUND

Corticobasal syndrome (CBS) is an atypical parkinsonian syndrome related to multiple underlying pathologies.

OBJECTIVE

To investigate if individual brain [¹⁸ F]fluorodeoxyglucose-positron emission tomography (FDG-PET) patterns could distinguish CBS due to Alzheimer's disease (AD) from other pathologies based on [¹¹ C]Pittsburgh Compound-B (PIB)-PET.

METHODS

Forty-five patients with probable CBS were prospectively evaluated regarding cognitive and movement disorders profile. They underwent FDG-PET and were distributed into groups: likely related to AD (CBS FDG-AD) or likely non-AD (CBS FDG-nonAD) pathology. Thirty patients underwent PIB-PET on a hybrid PET-magnetic resonance imaging equipment to assess their amyloid status. FDG and PIB-PET images were classified individually based on visual and semi-quantitative analysis, blinded to each other. Quantitative group analyses were also performed.

RESULTS

CBS FDG-AD group demonstrated worse cognitive performances, mostly concerning attention, memory, visuospatial domains, and displayed more myoclonus and hallucinations. The non-AD metabolic group presented more often limb dystonia, ocular motor dysfunction, motor perseveration, and dysarthria. All patients classified as CBS FDG-AD tested positive at PIB-PET compared to 3 of 20 in the non-AD group. The individual FDG-PET classification demonstrated 76.92% of sensitivity, 100% of specificity and positive predictive value and 88.5% of balanced accuracy to detect positive PIB-PET scans. Individuals with positive and negative PIB-PET showed hypometabolism in posterior temporoparietal areas and in thalamus and brainstem, respectively, mainly contralateral to most affected side, disclosing possible metabolic signatures of CBS variants.

CONCLUSION

FDG-PET was useful to predict AD and non-AD CBS variants depicting their specific degeneration patterns, different clinical features, and brain amyloid deposition. © 2020 International Parkinson and Movement Disorder Society.

Validation of the RUDAS for the Identification of Dementia in Illiterate and Low-Educated Older Adults in Lima, Peru

Objectives: To evaluate the performance of the Peruvian version of the Rowland Universal Dementia Assessment Scale (RUDAS-PE) in discriminating between controls and patients with mild cognitive impairment (MCI) and dementia in an illiterate population with low-levels of education. Methods: We compared the cognitive performance of 187 elderly subjects who were illiterate (controls n = 60; MCI n = 64; dementia n = 63). Neuropsychological measures included the RUDAS-PE, Mini-Mental State Examination (MMSE), INECO Frontal Screening (IFS), and Pfeffer Functional Activities Questionnaire (PFAQ). The results were compared to a neuropsychological evaluation (gold standard), including use of Clinical Dementia Rating (CDR) scores. Results: We found a Cronbach's alpha was 0.65; Spearman's correlation coefficient was 0.79 (p < 0.01). The area under the receiver operating characteristics curve for the RUDAS to discriminate dementia from MCI was 98.0% with an optimal cut-off <19 (sensitivity 95%, specificity 97%); whereas, to differentiate MCI and controls was 98.0% with an optimal cut-off <23 (sensitivity 89%, specificity 93%). Conclusions: Based on its excellent psychometric properties, we find the RUDAS-PE suitable to aid in the opportune detection of dementia in a geriatric illiterate population with low-levels of education.

Performance-based instrument to assess functional capacity in community-dwelling older adults

Functional capacity (FC) is a mediator between neuropsychological functions and real-world functioning, but there is a lack of evidence of its correlation in community-dwelling older adults. Objective: The study aim was to determine the FC level of community-dwelling older adults using the UCSD Performance-based Skills Assessment (UPSA) and to evaluate correlation with cognitive screening tests. Methods: Senior center participants were selected according to inclusion criteria: Portuguese fluency, age ≥60 years and self-reported independent living. The subject exclusion criteria were: dementia or other DSM-5 diagnoses, suicidal ideation or intent, non-completion of assessment battery, enrollment in another psychosocial intervention or pharmacotherapy study. FC level was determined by the UPSA, brief UPSA (UPSA-B) and Instrumental Activities of Daily Living scale (IADL’s). The Mini-Mental State Examination (MMSE), Memory of Figure Test (MFT), Verbal Fluency Test (VFT) and Clock Drawing Test (CDT) were used for cognitive assessment. A total of 35 subjects that had a mean age of 72 years, were predominantly females(88.6%) and had mean education level of 11.25 years were evaluated. Results: Mean UPSA and UPSA-B scores were 78.5 and 70, respectively. A statistically significant correlation was observed between the UPSA and IADL, MMSE and VFT. Conclusion: The UPSA serves as a screening assessment of FC in community-dwelling older adults, showing a positive correlation with cognitive screening tests.

Primary School Education May Be Sufficient to Moderate a Memory-Hippocampal Relationship

According to the cognitive reserve theory, intellectual stimuli acquired during life can prevent against developing cognitive impairment. The underlying cognitive reserve mechanisms were underexplored in low-educated individuals. Because episodic memory impairment due to hippocampal dysfunction is a key feature of Alzheimer's dementia (AD), we sought to look at a possible cognitive reserve mechanism by determining whether few years of education moderated the relationship between the hippocampal volumes and the episodic-memory scores. The sample was composed by 183 older adults, 40.1% male, with the median age of 78[76,82] years and the median years of education of 4[2,10] who had undergone an episodic-memory test and a 3-Tesla MRI scan to access the hippocampal volumes. Overall, 112 were cognitively healthy, 26 had cognitive impairment-no dementia (CIND) and 45 had dementia. We used multiple linear regression to assess whether the interaction between years of education and each hippocampal volume significantly predicted the episodic-memory scores' variance, controlling for cognitive diagnosis and nuisance variables. The interaction term with the left hippocampus (ß = 0.2, p = 0.043, CI = 1.0, 1.4), but not with the right (ß = 0.1, p = 0.218, CI = 0.9, 1.2) significantly predicted the variation on memory scores. The mechanism by which the left hippocampus seems to play a more important role on memory processing in more educated individuals needs to be further investigated and might be associated with a better use of mnemonic strategies or higher hippocampal connectivity. Because the sample's median years of education was four, which corresponds to primary school, we may infer that this level might be sufficient to contribute for building cognitive reserve.

Performance of the Pentagon Drawing test for the screening of older adults with Alzheimer's dementia

The Pentagon Drawing Test (PDT) is a common cognitive screening test.