Educational level and neuropsychological heterogeneity in dementia of the Alzheimer type

Episodic memory improvement in illiterate adults attending late-life education irrespective of low socioeconomic status: insights from the PROAME study

The majority of people with dementia live in low or middle-income countries (LMICs) where resources that play a crucial role in brain health, such as quality education, are still not widely available. In Brazil, illiteracy remains a prevalent issue, especially in communities with lower socioeconomic status (SES). The PROAME study set out to explore basic education in illiterate adults as a means to improve cognitive reserve.

Objective

This manuscript aims to explore the relationship between SES and learning, as well as cognitive outcomes, in an older illiterate population.

Methods

This six-month clinical trial (NCT04473235) involved 108 participants, of which 77 concluded all assessments, enrolled in late-life basic education. SES assessments included Quality of Urban Living Index, Municipal Human Development Index and Household SES calculated for each participant. Cognitive assessments encompassed the Free and Cued Selective Reminding Test (FCSRT), a word list to assess reading, and the Beta III matrix.

Results

The sample consisted primarily of women, with a mean age of 58.5. Participants improved their reading (p=0.01) and their FCSRT (p=0.003). Regarding episodic memory, women outperformed men (p=0.007) and younger participants improved more than their older counterparts (p=0.001). There was no association observed between SES and cognitive outcomes.

Conclusion

Irrespective of SES, participants demonstrated positive outcomes after attending basic education. These findings highlight that late life education could be an important non-pharmacologic preventative measure, especially in LMICs.

Resilience of Neural Cellularity to the Influence of Low Educational Level

BACKGROUND

Education is believed to contribute positively to brain structure and function, as well as to cognitive reserve. One of the brain regions most impacted by education is the medial temporal lobe (MTL), a region that houses the hippocampus, which has an important role in learning processes and in consolidation of memories, and is also known to undergo neurogenesis in adulthood. We aimed to investigate the influence of education on the absolute cell numbers of the MTL (comprised by the hippocampal formation, amygdala, and parahippocampal gyrus) of men without cognitive impairment.

METHODS

The Isotropic Fractionator technique was used to allow the anisotropic brain tissue to be transformed into an isotropic suspension of nuclei, and therefore assess the absolute cell composition of the MTL. We dissected twenty-six brains from men aged 47 to 64 years, with either low or high education.

RESULTS

A significant difference between groups was observed in brain mass, but not in MTL mass. No significant difference was found between groups in the number of total cells, number of neurons, and number of non-neuronal cells. Regression analysis showed that the total number of cells, number of neurons, and number of non-neuronal cells in MTL were not affected by education.

CONCLUSIONS

The results indicate a resilience of the absolute cellular composition of the MTL of typical men to low schooling, suggesting that the cellularity of brain regions is not affected by formal education.

Clinical Impact of PET With 18F-FDG and 11C-PIB in Patients With Dementia in a Developing Country

Introduction: The objective of this study was to evaluate the clinical impact PET with ¹⁸F-FDG and ¹¹C-PIB in patients with dementia in a developing country.

Methodology: Retrospective study of the patients referred for the evaluation of dementia to the only PET center in Uruguay. A total of 248 patients were identified, from which 70 patients were included based on the availability of medical history and clinical follow-up. Main outcomes included change in diagnosis, diagnostic dilemma and AD treatment. We evaluated the association of clinical outcomes with PET concordance with baseline diagnosis, diagnostic dilemma, level of education, AD pathology/Non-AD pathology (AD/Non-AD), baseline diagnosis and ¹¹C-PIB PET result.

Results: Baseline clinical diagnosis was concordant with ¹⁸F-FDG and ¹¹C-PIB PET results in 64.7 and 77.1% of the patients, respectively. Change in diagnosis after PET was identified in 30.0% of the patients and was associated with discordant ¹⁸F-FDG (p = 0.002) and ¹¹C-PIB (p < 0.001) PET results, previous diagnostic dilemma (p = 0.005), low education (p = 0.027), Non-AD baseline diagnosis (p = 0.027), and negative ¹¹C-PIB PET result (p < 0.001). Only the last variable remained significant in the multivariate analysis (adjusted p = 0.038). Diagnostic dilemma decreased after PET from 15.7 to 7.1% (p = 0.11) and was associated with Non-AD diagnosis (p = 0.002) and negative ¹¹C-PIB PET result (p = 0.003). Change in AD treatment after PET occurred in 45.7% of the patients.

Conclusion:¹⁸F-FDG and ¹¹C-PIB PET had a significant clinical impact in terms of change in diagnosis and treatment in patients with dementia in a developing country, similar to that reported in high-income countries.

Functional magnetic resonance imaging response as an early biomarker of cognitive decline in elderly patients with metabolic syndrome

OBJECTIVES

We assessed whether potential changes in brain activation patterns of elderly individuals with metabolic syndrome (MetS) who were cognitively healthy (without mild cognitive impairment or dementia) were associated with cognitive decline in executive function in the short-term.

METHOD

We analyzed 43 individuals (23 MetS, 20 controls) using a global geriatric evaluation, a neuropsychological battery, and task-related (attention) fMRI exam. Correlation analysis between the fMRI signal at baseline and cognitive impairment after 1year was based on the voxel-based Pearson coefficient, corrected for multiple comparisons.

RESULTS

At baseline, MetS patients showed reduced brain response in frontal and parietal regions compared to controls. After one year, the MetS group also showed a decline in verbal fluency performance. fMRI response in the right dorsolateral prefrontal cortex and bilateral parietal lobes was negatively correlated with verbal fluency decline in the MetS group.

DISCUSSION

Our results provide an early biomarker of the possible development of cognitive impairment, particularly in the executive function, of elderly individuals suffering from MetS. These findings also point to an up or down regulation which could be interpreted as compensatory mechanism for possible brain tissue burden caused by MetS.

Validation and cultural adaptation of the Arabic versions of the Mini-Mental Status Examination - 2 and Mini-Cog test

INTRODUCTION

The elderly population is increasing around the world, and the prevalence of dementia increases with age. Hence, it is expected that the number of people with dementia will increase significantly in the coming years. The Mini-Mental Status Examination - 2 (MMSE-2) and Mini-Cog are widely used tests to screen for dementia. These scales have good reliability and validity and are easy to administer in clinical and research settings.

AIM

The purpose of this study was to validate the Arabic versions of MMSE-2 and Mini-Cog. These scales were assessed against the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, Text Revision (DSM-IV-TR) criteria for dementia, as the gold standard.

METHODS

The standard versions of the MMSE-2 and Mini-Cog were translated to Arabic following the back-translation method. Then, a trained rater administered these tests to 134 Arab elderly aged >60 years. A physician, blind to the results of these two tests, assessed the participants for vascular dementia or probable Alzheimer's disease, based on the DSM-IV-TR criteria.

RESULTS

The sample included 67.2% Qataris. The mean age was 74.86 years (standard deviation =7.71), and 61.9% did not attend school. The mean of the adjusted scores of MMSE-2 based on age and education level was 19.60 (standard deviation =6.58). According to DSM-IV-TR, 17.2% of the participants had dementia. Sensitivity and specificity of the MMSE-2 and the Mini-Cog together were 71.4% and 61.6%, respectively, which were better than those of each test alone.

CONCLUSION

Together, the Arabic versions of MMSE-2 and Mini-Cog are good screening tools for cognitive impairment in Arabs.

Literacy as a determining factor for brain organization: from Lecours' contribution to the present day

This review aimed to discuss the influence of literacy and formal education on human brain organization, based on evidence drawn from three sources:

(1) results and limitations of a project coordinated by André Roch Lecours on the influence of illiteracy on brain organization and of studies on aphasia in illiterate populations;

(2) data on the impact of schooling on the neuropsychological assessment of healthy and brain-damaged individuals, and

(3) studies on the effect of schooling on dementia.

These findings suggest that schooling and literacy processes influence cerebral organization of healthy individuals, as well as of brain-lesion individuals and those with dementia. Concerning illiteracy, the systematic pioneering studies developed by Lecours and the continuity of his investigations were essential to alert the scientific and clinical communities to take into account the role of educational experience on cognitive processing and its brain substrates.

A new Brief computerized cognitive screening battery (CompCogs) for early diagnosis of Alzheimer's disease

Screening tests for early diagnosis of dementia are of great clinical relevance. The ideal test set must be brief and reliable, and should probe cognitive components impaired in Alzheimer’s disease (AD).

Synapse loss is greater in presenile than senile onset Alzheimer disease: implications for the cognitive reserve hypothesis

In the past, 'Alzheimer disease' (AD) referred to pathologic AD with clinical onset of dementia in the presenium, while 'senile dementia of the Alzheimer type' (SDAT) referred to senile onset AD. Because AD appears clinically homogeneous regardless of age of onset, the two subtypes in more recent years have not been distinguished. Pathologic differences have been noted, but synapse loss has not previously been compared between the two groups. Hypothesizing that synapse loss would be greater in presenile onset than senile onset AD, we compared synapse loss, as well as Alzheimer pathology in presenile and senile onset AD, using an ELISA method to quantify synaptophysin. Synaptophysin was significantly lower in presenile than senile AD in right frontal and bilateral parietal lobes. Neuritic plaque counts were significantly higher in presenile than senile AD in bilateral frontal and parietal lobes. Semi-quantitative evaluation of neurofibrillary tangles revealed significantly more tangles in bilateral frontal and parietal lobes in presenile than senile AD. Brain weight was significantly lower in presenile than senile AD. The differences in synapse loss and Alzheimer-type pathology in presenile and senile onset AD support the hypothesis that 'cognitive reserve' protects the human brain from neurodegenerative disease.

A relational approach to providing care for a person suffering from dementia

AIMS OF THE PAPER

This paper examines the care provision for people suffering from dementia and explores the potential benefits associated with an approach to care that emphasizes the importance of relationships.

BACKGROUND

Recent research findings have provided an incentive to re-evaluate the established approaches to care for this client group. Two separate studies identified education and intellectual stimulation as important determinants of the onset of Alzheimer's disease (Ott et al. 1995, Snowdon et al. 1996). These findings have encouraged the hypothesis that potential symptomatic benefits may be achieved by providing a more stimulating environment for people with dementia.

METHODS

A case study is outlined which illustrates an approach to caring influenced by the Continental philosopher, Emmanuel Levinas. Primacy is given to the relationships that make up caring, and not to a method that sets out to achieve an identified objective. The issue of mutual responsibility within the provision of care is highlighted in the case study.

FINDINGS

The hypothesis presented in this paper is that a person has more of an opportunity to develop to the limits of their potential by establishing the importance of relationships in providing care by means of education and training of the people involved. The beneficiaries might be the caregiver or the person in receipt of care.

CONCLUSIONS

An environment that attempts to educate people to recognize the importance of relationships will be more effective in achieving the potential benefits of symptom alleviation identified by the research into Alzheimer's disease outlined in this paper.

Elderly Japanese emigrants to Brazil before World War II: II. Prevalence of senile dementia

BACKGROUND

We previously showed the prevalence of dementia in the town of Tajiri (Miyagi Prefecture, Japan), and found it to be 8.0%. The first population-based study on dementia in Brazil (Catanduva) disclosed the prevalence as being 7.1%. To evaluate the effects of environment on development of dementia, elderly Japanese immigrants living in Brazil were examined. Brazil is the country with the largest number of Japanese immigrants.

METHODS

All immigrants aged 65 years and over from Miyagi Prefecture, living in the four cities of the São Paulo Metropolitan area were targeted (n = 192). We were able to examine 166 subjects (86.5%). The diagnosis of dementia was based on the DSM-IV with the severity assessed by the CDR (clinical dementia rating) scales. The cognitive ability screening instrument (CASI) was used for neuropsychological assessment.

RESULTS

Thirteen subjects were diagnosed with dementia, CDR 1-3, the prevalence being 7.8%. Older subjects suffered more from dementia, and, paradoxically, the more highly educated subjects also suffered more. All the CASI items, except for long-term memory and visual construction, significantly deteriorated in the CDR 0.5 group compared with the CDR 0 group.

COMMENTS

The prevalence of dementia was not thought to be affected by environmental factors. A paradoxically higher rate of dementia in the more educated subjects was probably due to the historical problems of the immigrants. Intact CASI item long-term memory in the CDR 0.5 group indicated that suspected dementia patients could maintain this function. This is the first epidemiological study on dementia in elderly Japanese immigrants in Brazil.

Prevalence of senile dementia in a rural community in Japan: the Tajiri project

Knowledge of the prevalence of dementia in different age groups is needed for the planning of a health policy. This study shows the prevalence of dementia and magnetic resonance imaging (MRI) findings in elderly people aged 65 years and over, living in the town of Tajiri in the northern part of Japan. They were shown by two cognitive screening tests, the Mini-Mental State examination (MMS) and the Dementia Screening Test (DST) and medical diagnosis. Two subject groups were assessed, those who completed both tests (Subjects I, n=2066) and those from among the 200 'MRI-administered subjects' who were interviewed and diagnosed (Subjects II, n=170). For Subjects I, there were 6.3 and 10.2% 'dementia range' according to the severe and mild criteria, respectively. As for Subjects II, 9.4% were clinically diagnosed as having dementia. They met the National Institute of Neurological and Communicative Disorders and Stroke and the Alzheimer's Disease and Related Disorders Association (NINCDS-ADRDA) criteria of probable Alzheimer's disease (AD) or possible AD with cerebrovascular disease. The estimated prevalence rate of dementia was 8.0%. Visual ratings of brain atrophy using MRI disclosed two distribution patterns. The 'continuous' pattern of the frontal and temporal lobes atrophy suggest that both are affected by the aging process, while a 'discontinuous' pattern of the hippocampal atrophy could indicate a pathologic background such as early changes of AD.

Individual differences in memory and executive function abilities during normal aging

The purpose of this study was to analyze the effects of some individual variables on memory and executive function test performance in normal aging individuals. Sixty subjects (21 males and 39 females), with a mean age of 69.66 (SD = 7.09) were selected. The following neuropsychological tests were selected. The following neuropsychological tests were administered: Associative Learning and Logical Memory from the Wechsler Memory Scale (WMS) (Wechsler, 1945), Associative Memory with Semantic Enhancement Test (AMSET) (Pineda, Galeano and Giraldo, 1991), Wisconsin Card Sorting Test (WSCT) (Heaton, 1981), and Verbal Fluency (phonologic and semantic). The effects of demographic (age, education, and sex) and some individual variables (academic history, working history, physical activity, and leisure activities) were measured. Age and education effects on test scores were observed, but no sex effect was found. Working history and leisure activities established significant differences in some test scores. A multiple regression analysis was performed. Not only demographic variables, but also individual variables were associated with memory, and albeit at a lesser extend, with executive function test scores. It was emphasized that not only demographic factors, but also individual variables have a significant effect on cognitive changes observed during normal aging.