A biological classification for Alzheimer's disease - amyloid, tau and neurodegeneration (A/T/N): results from the Argentine-Alzheimer's disease neuroimaging initiative

Allegri, Ricardo F. | 2019

The aim of this study was to describe the A/T/N research framework classification for AD in the Argentine ADNI cohort and to explore the prediction to develop dementia in a prospective two-year follow-up.

Corticobasal syndrome as a focal variant of Alzheimer’s disease

Mariani, Francesca | 2022-12-11

Presentamos el caso de una mujer de 60 años, con un déficit progresivo de memoria anterógrada de 2 años de evolución. Se realizó estudios 18F-FDG PET/C y 11C-PIB PET/CT compatibles con EA. En la evolución presentó un síndrome cortico basal típico, con signos extrapiramidales y distonia de miembro superior izquierdo. Tanto los hallazgos de imagen, como la presentación clínica son consistentes con una presentación focal de EA

Corticobasal syndrome as a focal variant of Alzheimer’s disease

Mariani, Francesca | 2022

We present a 60-year-old woman with a 2-year history of progressive anterograde memory deficit, that evolved with a typical corticobasal syndrome with extrapyramidal signs and left superior limb dystonia. 18F-FDG and 11C-PIB PET/CT studies supported the diagnosis of Alzheimer’s disease associating a corticobasal syndrome.

Cuestionario de detección de deterioro cognitivo AD8-arg para su uso atención primaria de la salud en Argentina

Blanco, Romina | 2016-10-21

Memory complaint may be very common in elderly people over 65, but also is present in early stage of dementing processes. Instruments to detect dementia in primary health care must be easy and quickly to be applied. In 2005, Galvin et al. developed a questionnaire Alzheimer's Disease 8 (AD8) which was based on a brief interview with and informant to detect subjects with dementia. The objective of this work was to perform the translation, adaptation to the Spanish language near the Rio de la Plata and to establish the validity, reliability and discriminative proprieties of AD8-arg for use in primary care. Methods 18 patients with dementia of Alzheimer type, 25 with mild cognitive impairment and 19 normal controls matched by age and education were assessed with the AD8-arg and an extensive neuropsychological battery. Concurrent validity was strong with significant correlation with MMSE (-0,464: P<0.001) and CDR (0,514; P<0.001). Internal consistency was adequate correlating with all cognitive tests. The area under the ROC curve was 0.89 and a cutoff score of 2 had a sensitivity of 0.80 and specificity of 0.83 showing excellent discrimination between demented and non-demented patients. The AD8-arg is a tool for quick and easy administration with adequate psychometric properties for use in screening of dementia in primary care in our region.

Dementia in Latin America assessing the present and envisioning the future

Parra, Mario Alfredo | 2018-06-30

The demographic structure of Latin American countries (LAC) is fast approaching that of developing countries, and the predicted prevalence of dementia in the former already exceeds the latter. Dementia has been declared a global challenge, yet regions around the world show differences in both the nature and magnitude of such a challenge. This article provides evidence and insights on barriers which, if overcome, would enable the harmonization of strategies to tackle the dementia challenge in LAC. First, we analyze the lack of available epidemiologic data, the need for standardizing clinical practice and improving physician training, and the existing barriers regarding resources, culture, and stigmas. We discuss how these are preventing timely care and research. Regarding specific health actions, most LAC have minimal mental health facilities and do not have specific mental health policies or budgets specific to dementia. In addition, local regulations may need to consider the regional context when developing treatment and prevention strategies. The support needed nationally and internationally to enable a smooth and timely transition of LAC to a position that integrates global strategies is highlighted. We focus on shared issues of poverty, cultural barriers, and socioeconomic vulnerability. We identify avenues for collaboration aimed to study unique populations, improve valid assessment methods, and generate opportunities for translational research, thus establishing a regional network. The issues identified here point to future specific actions aimed at tackling the dementia challenge in LAC.

Estudio descriptivo del lenguaje comprensivo y denominativo en adultos mayores entre 60 y 90 años con enfermedad de alzhéimer y envejecimiento normal 

Pirela Atencio, Yamile | 2013-06-17

Alzheimer's disease has a high prevalence in the older population, it is therefore necessary that the recognition of characteristics of language and its disorders in people with normal and pathological aging, and that this differentiation may enhance the utility in the diagnosis differential. Therefore we intend to describe the processes of naming and comprehensionassessed by the Boston Naming Test and Token Test in older adults with Alzheimer disease (AD) and normal aging (EN) between 60 and 90years, in Barranquillacity, Colombia. Methodologically this research is descriptive, cross-sectional, which contrasted two groups of 30 subjects each, one called control (EN) and the other case (EE). The results show that patients with AD had a significantly lower performance (p <0.05) in the functions of naming and comprehension in adults with Alzheimer's disease versus normal aging adults, and it also found significant differences according to cognitive status evaluated through the Mini Mental State Examination MMSE. This is considered highly relevant further research of this kind in our context in order to design language assessment protocols that allow for better differential diagnosis, because in our country that is not recorded extensive literature on this issue that based on epidemiology affects not only physical, but emotional, family and society.

Global burden of 369 diseases and injuries in 204 countries and territories, 1990-2019: a systematic analysis for the Global Burden of Disease Study 2019

Abbafati, Cristiana | 2020

Identifying the most appropriate classifier for underpinning assistive technology adoption for people with dementia: an integration of Fuzzy AHP and VIKOR methods

Ortíz-Barrios, Miguel | 2020-07-10

Recently, the number of People with Dementia (PwD) has been rising exponentially across the world. The main symptoms that PwD experience include AQ1 impairments of reasoning, memory, and thought. Owing to the burden faced by this chronic condition, Assistive Technology-based solutions (ATS) have been prescribed as a form of treatment. Nevertheless, it is widely acknowledged that low adoption rates of ATS have hampered their benefits within a health and social care context. It is then necessary to effectively discriminate between adopters and non-adopters of such solutions to avoid cost implications, improve the life quality of adopters, and find intervention alternatives for non-adopters. Several classifiers have been proposed as advancement towards the personalisation of self-management interventions for dementia in a scalable way. As multiple algorithms have been developed, an important step in technology adoption is to select the most appropriate classification alternative based on different criteria. This paper presents the integration of Fuzzy AHP (FAHP) and VIKOR to address this challenge. First, FAHP was used to calculate the criteria and sub-criteria weights under uncertainty and then VIKOR was implemented to rank the classifiers. A case study considering a mobile-based self-management and reminding solution for PwD is described to validate the proposed approach. The results revealed that Easiness of interpretation (GW = 0.192) and Handling of missing data (GW = 0.145) were the two most important criteria. Furthermore, SVM (Qj = 1.0) and AB (Qj = 0.891) were concluded to be the most suitable classifiers for supporting ATS adoption in PwD.

Latin America has been under-represented in dementia clinical trials, we must turn the corner

Allegri, Ricardo Francisco | 2022-06-11

The world’s population is aging, life expectancy is increasing in the past century as result of the improvements in healthcare and the people arrive to live longer and healthier. However, this has also resulted in increase the number of people with age-re lated diseases like most of dementia etiologies (fundamentally Alzheimer and Vascular dementia). The growth of people with dementia in the next 20 years will be exponential around the world but even more in those countries with Low and Medium Incomes (LMIC) due to the recently and future improve in health care and quality of life

Literacy level and executive control in healthy older peruvian adults

Soto-Añari, Marcio | 2021-08-26

Introduction: Early-life educational experiences are associated with cognitive performance in aging. Early literacy seems to improve executive control mechanisms, however, it is not clear whether early education would still be an advantage in countries like Peru, where access to and quality of education is highly variable. Aim: Our objective was to analyze the association of literacy level with executive control factors. Method: We evaluated 93 healthy older adults with a clinical protocol that included the Mini-Mental State Examination, the Geriatric Depression Scale and Global Dementia Staging. We also used a neuropsychological executive function battery which included the Trail-Making Test parts A and B, the Stroop Test, phonological and semantic verbal fluency tasks, Forward and Backward Digits, Numbers and Letters of the Wechsler Scale, and the Go/No-Go task. We used a principal component analysis for the dimensional reduction of the variables. To measure the level of literacy we used the word accentuation test (WAT). Results: We observed statistically significant correlations between the principal components (PCs) of working memory, cognitive flexibility and inhibitory control with the WAT scores. Furthermore, we observed that processing speed and WAT predict the scores on PCs factors better than years of education and age. Conclusions: Literacy level correlates more closely with better cognitive performance than years of education and thus, might improve executive control factors that could compensate and protect against brain changes in cognitive decline and dementia.

Moving from neurodegenerative dementias, to cognitive proteinopathies, replacing “where” by “what”

Allegri, Ricardo Francisco | 2020-09-18

Neurodegenerative dementias have been described based on their phenotype, in relation to selective degeneration occurring in a particular neuroanatomical system. More recently however, the term proteinopathy has been introduced to describe diseases in which one or more altered proteins can be detected. Neurodegenerative diseases can be produced by more than one abnormal protein and each proteinopathy can determine different clinical phenotypes. Specific biomarkers have now been linked to certain molecular pathologies in live patients. In 2016, a new biomarker-based classification, currently only approved for research in Alzheimer’s disease, was introduced. It is based on the evaluation three biomarkers: amyloid (A) detected on amyloid-PET or amyloid- beta 42 assay in CSF; tau (T) measured in CSF as phosphorylated tau or on tau PET imaging; and neuronal injury/neurodegeneration (N), detected by total T-tau in CSF, FDG PET hypometabolism and on MRI brain scan. Results of clinical research using the ATN biomarkers at FLENI, a Neurological Institute in Buenos Aires, Argentina have, since 2011, contributed to ongoing efforts to move away from the concept of neurodegenerative dementias and more towards one of cognitive proteinopathies. Today, clinical diagnosis in dementia can only tell us “where” abnormal tissue is found but not “what” molecular mechanisms are involved

Selecting the most suitable classification algorithm for supporting assistive technology adoption for people with dementia: a multicriteria framework

Ortiz Barrios, Miguel Angel | 2019-07-03

The number of people with dementia (PwD) is increasing dramatically. PwD exhibit impairments of reasoning, memory, and thought that require some form of self‐management intervention to support the completion of everyday activities while maintaining a level of independence. To address this need, efforts have been directed to the development of assistive technology solutions, which may provide an opportunity to alleviate the burden faced by the PwD and their carers. Nevertheless, uptake of such solutions has been limited. It is therefore necessary to use classifiers to discriminate between adopters and nonadopters of these technologies in order to avoid cost overruns and potential negative effects on quality of life. As multiple classification algorithms have been developed, choosing the most suitable classifier has become a critical step in technology adoption. To select the most appropriate classifier, a set of criteria from various domains need to be taken into account by decision makers. In addition, it is crucial to define the most appropriate multicriteria decision‐making approach for the modelling of technology adoption. Considering the above‐mentioned aspects, this paper presents the integration of a five‐phase methodology based on the Fuzzy Analytic Hierarchy Process and the Technique for Order of Preference by Similarity to Ideal Solution to determine the most suitable classifier for supporting assistive technology adoption studies. Fuzzy Analytic Hierarchy Process is used to determine the relative weights of criteria and subcriteria under uncertainty and Technique for Order of Preference by Similarity to Ideal Solution is applied to rank the classifier alternatives. A case study considering a mobile‐based self‐management and reminding solution for PwD is described to validate the proposed approach. The results revealed that the best classifier was k‐nearest‐neighbour with a closeness coefficient of 0.804, and the most important criterion when selecting classifiers is scalability. The paper also discusses the strengths and weaknesses of each algorithm that should be addressed in future research.

World Health Organization have just launched a Blueprint for Dementia Research Inglés. Some notes to boost dementia research in Latin America…

Allegri, Ricardo Francisco | 2022

Dementia is the most important cause of disability and dependency in older adults and currently affects more than 55 million people, 60% of whom live in Low- and Middle-­Income Countries (LMIC). The number of people with dementia with increasing life expectancy will grow globally in the coming years, but even more in LMIC such as the Latin American (LA) countries.