Comparative study of the word capacity and episodic memory of patients with degenerative dementia

INTRODUCTION

Although the absence of memory impairment was considered among the diagnostic criteria to differentiate Alzheimer's disease (AD) from Behavioural Variant of Frontotemporal Dementia (bvFTD), current and growing evidence indicates that a significant percentage of cases of bvFTD present with episodic memory deficits. In order to compare the performance profile of the naming capacity and episodic memory in patients with AD and bvFTD the present study was designed.

METHODS

Cross-sectional and analytical study with control group (32 people). The study included 42 people with probable AD and 22 with probable bvFTD, all over 60 years old. Uniform Data Set instruments validated in Spanish were used: Multilingual Naming Test (MINT), Craft-21 history and Benson's complex figure, among others.

RESULTS

A higher average age was observed among the patients with AD. The naming capacity was much lower in patients with bvFTD compared to patients with AD, measured according to the MINT and the nouns/verbs naming coefficient. All patients with bvFTD, 73.81% of those with AD and only 31.25% of the control group failed to recognise Benson's complex figure. All differences were statistically significant (p < 0.001).

RESULTS

This study confirms the amnesic profile of patients with AD and reveals the decrease in naming capacity in patients with bvFTD, an area of ​​language that is typically affected early on with executive functions, according to recent findings.

CONCLUSIONS

Patients with AD perform worse in verbal and visual episodic memory tasks, while patients with bvFTD perform worse in naming tasks. These findings open the possibility of exploring the mechanisms of prefrontal participation in episodic memory, typically attributed to the hippocampus.

Comparative Study of the Word Capacity and Episodic Memory of Patients with Degenerative Dementia

INTRODUCTION

Although the absence of memory impairment was considered among the diagnostic criteria to differentiate Alzheimer's disease (AD) from Behavioural Variant of Frontotemporal Dementia (bvFTD), current and growing evidence indicates that a significant percentage of cases of bvFTD present with episodic memory deficits. In order to compare the performance profile of the naming capacity and episodic memory in patients with AD and bvFTD the present study was designed.

METHODS

Cross-sectional and analytical study with control group (32 people). The study included 42 people with probable AD and 22 with probable bvFTD, all over 60 years old. Uniform Data Set instruments validated in Spanish were used: Multilingual Naming Test (MINT), Craft-21 history and Benson's complex figure, among others.

RESULTS

A higher average age was observed among the patients with AD. The naming capacity was much lower in patients with bvFTD compared to patients with AD, measured according to the MINT and the nouns/verbs naming coefficient. All patients with bvFTD, 73.81% of those with AD and only 31.25% of the control group failed to recognise Benson's complex figure. All differences were statistically significant (p <0.001).

RESULTS

This study confirms the amnesic profile of patients with AD and reveals the decrease in naming capacity in patients with bvFTD, an area of language that is typically affected early on with executive functions, according to recent findings.

CONCLUSIONS

Patients with AD perform worse in verbal and visual episodic memory tasks, while patients with bvFTD perform worse in naming tasks. These findings open the possibility of exploring the mechanisms of prefrontal participation in episodic memory, typically attributed to the hippocampus.

[Performance of cognitive brief test in elderly patients with dementia in advanced stage living in an urban community of Lima, Peru]

Objectives.

Evaluate the performance of clock drawing test- Manos versión (PDR-M) and Mini Mental State Examination -Peruvian version (MMSE) to detect dementia in a sample based on urban community of Lima, Peru.

Materials and methods.

This study is a secondary analysis database, observational, analytical and cross-sectional, the gold standard was the clinical and the neuropsychological evaluations together. Performance testing individually and in combination were evaluated.. Data were obtained from prevalence study conducted in 2008 in Cercado de Lima.

Results.

MMSE performance for evaluation of patients with dementia of any kind showed sensitivity of 64,1%, specificity of 84,1%, PPV of 24.4%, NPV of 96.7%, PLR of 4,03 and NLR of 0,43. PDR-M showed sensitivity of 89,3%, specificity of 98,1%, PPV of 79.3%, NPV of 99.1%, PLR of 47,79 and NLR of 0,11. When both tests were applied, and at least one of them was positive, they showed sensitivity 98.1%, specificity 84.1%, PPV of 33.1%, NPV of 99.8%, PLR of 6,17 and NLR of 0,02. When performing separate analysis of Alzheimer-type dementia and non- Alzheimer dementia, the values of the parameters do not differ substantially from those obtained for dementia of any kind.

Conclussions.

The combination of MMSE and PDR-M show good discriminative ability to detect moderate and severe dementia in population living in urban community in Lima.

Memory Alteration Test to Detect Amnestic Mild Cognitive Impairment and Early Alzheimer's Dementia in Population with Low Educational Level

Background/Aims: Short tests to early detection of the cognitive impairment are necessary in primary care setting, particularly in populations with low educational level. The aim of this study was to assess the performance of Memory Alteration Test (M@T) to discriminate controls, patients with amnestic Mild Cognitive Impairment (aMCI) and patients with early Alzheimer’s Dementia (AD) in a sample of individuals with low level of education.

Methods: Cross-sectional study to assess the performance of the M@T (study test), compared to the neuropsychological evaluation (gold standard test) scores in 247 elderly subjects with low education level from Lima-Peru. The cognitive evaluation included three sequential stages: (1) screening (to detect cases with cognitive impairment); (2) nosological diagnosis (to determinate specific disease); and (3) classification (to differentiate disease subtypes). The subjects with negative results for all stages were considered as cognitively normal (controls). The test performance was assessed by means of area under the receiver operating characteristic (ROC) curve. We calculated validity measures (sensitivity, specificity and correctly classified percentage), the internal consistency (Cronbach’s alpha coefficient), and concurrent validity (Pearson’s ratio coefficient between the M@T and Clinical Dementia Rating (CDR) scores).

Results: The Cronbach’s alpha coefficient was 0.79 and Pearson’s ratio coefficient was 0.79 (p < 0.01). The AUC of M@T to discriminate between early AD and aMCI was 99.60% (sensitivity = 100.00%, specificity = 97.53% and correctly classified = 98.41%) and to discriminate between aMCI and controls was 99.56% (sensitivity = 99.17%, specificity = 91.11%, and correctly classified = 96.99%).

Conclusions: The M@T is a short test with a good performance to discriminate controls, aMCI and early AD in individuals with low level of education from urban settings.

Utilidad de la batería ejecutiva y cognición social de INECO en la evaluación de funciones ejecutivas de una serie de pacientes peruanos con demencia fronto-temporal, variante conductual

Los síntomas característicos de la demencia fronto-temporal, variante conductual reflejan disfunción del cortex prefrontal ventromedial, y no existe consenso respecto a las pruebas neuropsicológicas más sensibles y específicos para evaluarlos. Objetivos: El objetivo de este estudio fue detectar alteraciones específicas de funciones ejecutivas y de cognición social en pacientes con demencia fronto-temporal variante conductual. Material y Métodos: Evaluamos la batería ejecutiva y cognición social del Instituto de Neurología Cognitiva (INECO), la cual incluye pruebas de teoría de la mente (test de la mirada y test de metida de pata), tareas del hotel, tests de diligencias multiples-versión del hospital y el Iowa Gambling Test para toma de decisiones. Los pacientes fueron divididos en dos grupos según su desempeño en el Addenbrooke´s Cognitive Examination. Resultados: Pacientes del grupo de Addenbrooke´s Cognitive Examination Bajo mostró resultados significativamente menores, respecto a los controles en muchas de las tareas de la batería ejecutiva estándar y en la batería ejecutiva y cognición social de INECO. Pero, el grupo deAddenbrooke´s Cognitive Examination Alto no difirió de los controles en muchas de las tareas de la batería ejecutiva estándar, mientras que encontramos diferencias significativas en los pacientes con demencia fronto-temporal con Addenbrooke´s Cognitive Examination Alto y los controles en la mayoría de las tareas de la batería ejecutiva y cognición social. Conclusiones: La batería ejecutiva y cognición social de INECO es más sensible para detectar alteraciones ejecutivas y de cognición social en estadios precoces de demencia fronto-temporal, variante conductual que las tareas empleadas en la batería ejecutiva estándar.