Cognitive Reserve Factors in a Developing Country: Education and Occupational Attainment Lower the Risk of Dementia in a Sample of Lebanese Older Adults

Dementia incidence among a cohort of lebanese older adults: first incidence estimates from the Middle East and North Africa region

Objective

To provide the first estimates of dementia incidence rates among elderly in Lebanon.

Methods

The cohort established in 2013 consisted of 470 elderly from Beirut and Mount Lebanon, who consented to be followed-up. In 2017, we reached 341 participants/informants, achieving a response rate of 72.6%. The validated Arabic version of the 10/66 Dementia Research Group diagnostic tool was administered through face-to-face interviews. Direct age standardization was applied to the data using the Western European population distribution. Age-, sex- and location-specific incidence rates were estimated.

Results

After 3.5 years of follow up, 19 new cases of dementia were identified among 229 surviving participants. The crude incidence rate was 16.8 per 1,000 p-y, and the age standardized rate was 20.5 per 1,000 p-y. The incidence rate increased with age, going from 6.5 for those aged 65-74 years to 54.0 for those aged 85-89 years. Incidence rate was higher among females than males (20.7 vs.12.0), and higher in Mount Lebanon, as compared to the capital city Beirut (19.5 vs.14.9).

Conclusion

Dementia incidence rate was close to European and North American countries' estimates. The use of validated tools increased the internal validity of our results. A large cohort study is warranted to confirm these results.

Mapping computational cognitive profiles of aging to dissociable brain and sociodemographic factors

Aging is associated with declines in cognition and brain structural integrity. However, there is equivocality over (1) the specificity of affected domains in different people, (2) the location of associated patterns of brain structural deterioration, and (3) the sociodemographic factors contributing to 'unhealthy' cognition. We aimed to identify cognitive profiles displayed by older adults and determine brain and sociodemographic features potentially shaping these profiles. A sample of Southeast-Asian older adults (N = 386) participated in a multi-session study comprising cognitive testing, neuroimaging, and a structured interview. We used computational models to extract latent mechanisms underlying cognitive flexibility and response inhibition. Data-driven methods were used to construct cognitive profiles based on standard performance measures and model parameters. We also investigated grey matter volume and machine-learning derived 'brain-ages'. A profile associated with poor set-shifting and rigid focusing was associated with widespread grey matter reduction in cognitive control regions. A slow responding profile was associated with advanced brain-age. Both profiles were correlated with poor socioeconomic standing and cognitive reserve. We found that the impact of sociodemographic factors on cognitive profiles was partially mediated by total grey and white matter, and dorsolateral prefrontal and cerebellar volumes. This study furthers understanding of how distinct aging profiles of cognitive impairment uniquely correspond to specific vs. global brain deterioration and the significance of socioeconomic factors in informing cognitive performance in older age.

Degree of multilingual engagement modulates resting state oscillatory activity across the lifespan

Multilingualism has been demonstrated to lead to a more favorable trajectory of neurocognitive aging, yet our understanding of its effect on neurocognition across the lifespan remains limited. We collected resting state EEG recordings from a sample of multilingual individuals across a wide age range. Additionally, we obtained data on participant multilingual language use patterns alongside other known lifestyle enrichment factors. Language experience was operationalized via a modified multilingual diversity (MLD) score. Generalized additive modeling was employed to examine the effects and interactions of age and MLD on resting state oscillatory power and coherence. The data suggest an independent modulatory effect of individualized multilingual engagement on age-related differences in whole brain resting state power across alpha and theta bands, and an interaction between age and MLD on resting state coherence in alpha, theta, and low beta. These results provide evidence of multilingual engagement as an independent correlational factor related to differences in resting state EEG power, consistent with the claim that multilingualism can serve as a protective factor in neurocognitive aging.

Influence of cognitive reserve on cognitive and motor function in α-synucleinopathies: A systematic review and multilevel meta-analysis

Cognitive reserve has shown promise as a justification for neuropathologically unexplainable clinical outcomes in Alzheimer's disease. Recent evidence suggests this effect may be replicated in conditions like Parkinson's disease, dementia with Lewy bodies, and multiple system atrophy. However, the relationships between cognitive reserve and different cognitive abilities, as well as motor outcomes, are still poorly understood in these conditions. Additionally, it is unclear whether the reported effects are confounded by medication. This review analysed studies investigating the relationship between cognitive reserve and clinical outcomes in these α-synucleinopathy cohorts, identified from MEDLINE, Scopus, psycINFO, CINAHL, and Web of Science. 85 records, containing 176 cognition and 31 motor function effect sizes, were pooled using multilevel meta-analysis. There was a significant, positive association between higher cognitive reserve and both better cognition and motor function. Cognition effect sizes differed by disease subtype, cognitive reserve measure, and outcome type; however, no moderators significantly impacted motor function. Review findings highlight the clinical implications of cognitive reserve and importance of engaging in reserve-building behaviours.

Longitudinal validation of cognitive reserve proxy measures: a cohort study in a rural Chinese community

BACKGROUND

While evidence supports cognitive reserve (CR) in preserving cognitive function, longitudinal validation of CR proxies, including later-life factors, remains scarce. This study aims to validate CR's stability over time and its relation to cognitive function in rural Chinese older adults.

METHODS

Within the project on the health status of rural older adults (HSRO), the survey included baseline assessment (2019) and follow-up assessment (2022). 792 older adults (mean age: 70.23 years) were followed up. The confirmatory factor analysis (CFA) was constructed using cognitive reserve proxies that included years of formal education, social support, hobbies, and exercise. We examined the longitudinal validity of the CR factor using confirmatory factor analyses and measurement invariance and explored the association of CR with cognition using Spearman's correlation and Generalized Estimating Equations (GEE).

RESULTS

The results showed that CR's CFA structure was stable over time (T0, χ2/df: 3.21/2; RMSEA: 0.02, and T1, χ2/df: 7.47/2; RMSEA: 0.05) and that it accepted both configural and metric invariance (Δχ2/df = 2.28/3, P = 0.52). In addition, it was found that CR had a stable positive relationship with cognitive function across time (T0, r = 0.54; T1, r = 0.49). Furthermore, longitudinal CR were associated with MMSE (β = 2.25; 95%CI = 2.01 ~ 2.49).

CONCLUSIONS

This study provided valuable evidence on the stability and validity of cognitive reserve proxy measures in rural Chinese older adults. Our findings suggested that cognitive reserve is associated with cognitive function over time and highlighted the importance of accumulating cognitive reserve in later life.

A new nomogram model for the individualized prediction of mild cognitive impairment in elderly patients with type 2 diabetes mellitus

Background

A high risk of developing mild cognitive impairment (MCI) is faced by elderly patients with type 2 diabetes mellitus (T2DM). In this study, independent risk factors for MCI in elderly patients with T2DM were investigated, and an individualized nomogram model was developed.

Methods

In this study, clinical data of elderly patients with T2DM admitted to the endocrine ward of the hospital from November 2021 to March 2023 were collected to evaluate cognitive function using the Montreal Cognitive Assessment scale. To screen the independent risk factors for MCI in elderly patients with T2DM, a logistic multifactorial regression model was employed. In addition, a nomogram to detect MCI was developed based on the findings of logistic multifactorial regression analysis. Furthermore, the accuracy of the prediction model was evaluated using calibration and receiver operating characteristic curves. Finally, decision curve analysis was used to evaluate the clinical utility of the nomogram.

Results

In this study, 306 patients were included. Among them, 186 patients were identified as having MCI. The results of multivariate logistic regression analysis demonstrated that educational level, duration of diabetes, depression, glycated hemoglobin, walking speed, and sedentary duration were independently correlated with MCI, and correlation analyses showed which influencing factors were significantly correlated with cognitive function (p <0.05). The nomogram based on these factors had an area under the curve of 0.893 (95%CI:0.856-0.930)(p <0.05), and the sensitivity and specificity were 0.785 and 0.850, respectively. An adequate fit of the nomogram in the predictive value was demonstrated by the calibration plot.

Conclusions

The nomogram developed in this study exhibits high accuracy in predicting the occurrence of cognitive dysfunction in elderly patients with T2DM, thereby offering a clinical basis for detecting MCI in patients with T2DM.

Determinants of multimorbidity in older adults in Iran: a cross-sectional study using latent class analysis on the Bushehr Elderly Health (BEH) program

BACKGROUND AND OBJECTIVES

Multimorbidity, defined as the presence of two or more long-term health conditions in an individual, is one of the most significant challenges facing health systems worldwide. This study aimed to identify determinants of classes of multimorbidity among older adults in Iran.

RESEARCH DESIGN AND METHODS

In a cross-sectional sample of older adults (aged ≥ 60 years) from the second stage of the Bushehr Elderly Health (BEH) program in southern Iran, latent class analysis (LCA) was used to identify patterns of multimorbidity. Multinomial logistic regression was conducted to investigate factors associated with each multimorbidity class, including age, gender, education, household income, physical activity, smoking status, and polypharmacy.

RESULTS

In 2,426 study participants (mean age 69 years, 52% female), the overall prevalence of multimorbidity was 80.2%. Among those with multimorbidity, 3 latent classes were identified. These comprised: class 1, individuals with a low burden of multisystem disease (56.9%); class 2, individuals with predominantly cardiovascular-metabolic disorders (25.8%) and class 3, individuals with predominantly cognitive and metabolic disorders (17.1%). Compared with men, women were more likely to belong to class 2 (odds ratio [OR] 1.96, 95% confidence interval [CI] 1.52-2.54) and class 3 (OR 4.52, 95% CI 3.22-6.35). Polypharmacy was associated with membership class 2 (OR 3.52, 95% CI: 2.65-4.68) and class 3 (OR 1.84, 95% CI 1.28-2.63). Smoking was associated with membership in class 3 (OR 1.44, 95% CI 1.01-2.08). Individuals with higher education levels (59%) and higher levels of physical activity (39%) were less likely to belong to class 3 (OR 0.41; 95% CI: 0.28-0.62) and to class 2 (OR 0.61; 95% CI: 0.38-0.97), respectively. Those at older age were less likely to belong to class 2 (OR 0.95).

DISCUSSION AND IMPLICATIONS

A large proportion of older adults in Iran have multimorbidity. Female sex, polypharmacy, sedentary lifestyle, and poor education levels were associated with cardiovascular-metabolic multimorbidity and cognitive and metabolic multimorbidity. A greater understanding of the determinants of multimorbidity may lead to strategies to prevent its development.

Spatial scale effects on associations between built environment and cognitive function: Multi-Ethnic Study of Atherosclerosis

Built environments have the potential to favorably support cognitive function. Despite growing work on this topic, most of the work has ignored variation in the spatial scale of the effect. The issue with spatial scale effects is that the size and shape of the areal unit within which built environment characteristics are measured naturally influence the built environment exposure metric and thus the estimated associations with health. We used spatial distributed lag modeling (DLM) to estimate how associations between built environment exposures (walkable destinations [WD], social destinations [SD]) and change in cognition varied across distance of these destinations from participants' residences. Cognition was assessed as maintained/improved processing speed (PS) and global cognition (GC). Person-level data from Exam 5 (2010-2012) and Exam 6 (2016-2018) of the Multi-Ethnic Study of Atherosclerosis was used (N = 1380, mean age 67). Built environment data were derived from the National Establishment Time Series. Higher availability of walkable and social destinations at closer distance from participants' residence was associated with maintained/improved PS. The adjusted associations between maintained/improved PS and destinations waned with increasing distance from the residence; associations were evident until approximately 1.9-km for WD and 1.5-km for SD. Associations were most apparent for participants living in areas with high population density. We found little evidence for associations between change in GC and built environment at any distance. These results highlight the importance of identifying appropriate spatial scale to understand the mechanisms for built environment-cognition associations.

Validation of the Cognitive Reserve Index Questionnaire (CRIq) in Arabic

Cognitive reserve is the adaptability of cognitive processes in the face of brain aging and pathology. This study aimed to validate the Arabic version of the Cognitive Reserve Index Questionnaire (CRIq) in a healthy Lebanese sample. CRIq assesses cognitive reserve through three domains: education, working activity, and leisure time. Statistical measures, including descriptive and regression analysis along with structural equation modeling, were utilized to investigate the convergent and discriminant validity of the CRIq, incorporating fluid intelligence (Gf) and measures of cognitive function, long-term memory encoding and retrieval (Glr), and processing speed (Gs). Results from 174 participants revealed that the activities assessed by the CRIq-Arabic were comparable to the original CRIq study, with slight cultural differences. The internal consistency of the CRIq-Arabic was good (Cronbach's α = 0.88), indicating reliability. Convergent validity was confirmed, with moderate to high loadings on the cognitive reserve latent construct. Discriminant validity was supported as correlations between cognitive reserve variables and non-target constructs (Gf, Glr, and Gs) were less than 1. The findings provide an initial psychometric validation of the CRIq-Arabic. Further research of clinical samples is needed to enhance its utility in neuropsychological practice.

Effect of Mediterranean Dietary Pattern on Cognitive Status in Community-Dwelling Older Adults

Modifiable factors associated with cognitive decline (CD) require more attention, particularly dietary patterns. This study aimed to investigate the link between cognitive decline and associated factors, particularly dietary patterns (DPs), in community-dwelling older Lebanese of modest economic status. Our cross-sectional national study included 352 participants above 60 years old, from the medico-social centers of the ministry of social affairs all over the country. CD was screened based on literacy. Nutritional and dietary data were collected through a validated food frequency questionnaire. DPs were extracted by the K-mean cluster analysis. CD was found in 32.7% and 61.5% of literate and illiterate groups, respectively. Identified DPs included a Westernized type and Mediterranean type, with high and moderate food intakes. In the context of literacy, independent factors associated with CD were age above 80 years, living in Beirut, frailty, and adopting a Westernized (OR = 3.08, 95% CI: 1.22-7.8) and a high-intake Mediterranean DP (OR = 2.11, 95% CI: 1.05-4.22). In the context of illiteracy, the same factors were associated with CD, but not DP nor frailty, with an age cut-off at 78 years. In a Lebanese sample of older adults, factors associated with CD depend on the level of literacy, with DP only associated with CD in the context of literacy.

Higher education level as a protective factor against executive dysfunction in patients with epilepsy in Mataram, Indonesia

OBJECTIVE

Since the concept of cognitive reserve is applicable in epilepsy-associated cognitive impairment, the role of cognitive reserve components as a protective factor against epilepsy-associated executive dysfunction needs further investigation. This study aimed at investigating the association between cognitive reserve components and the frequency of epilepsy-associated executive dysfunction in Mataram, Indonesia.

METHODS

This case-control study involved both epilepsy outpatient and healthy participants recruited consecutively in 5 hospitals in Mataram, between October 2021 and September 2022. Data on sociodemographic, cognitive reserve components, and executive function status were collected from both groups, while data on seizure were collected only from epilepsy participants. The association between cognitive reserve components and the frequency of epilepsy-associated executive dysfunction was tested using logistic regression.

RESULTS

A total of 119 epilepsy patients and 93 healthy participants were recruited. The frequency of epilepsy-associated executive dysfunction was 50.4%. Multivariate logistic regression analysis showed that higher education level was the only cognitive reserve component protective against epilepsy-associated executive dysfunction (odds ratio [OR]: 3.36; 95% confidence interval [CI]: 1.33 - 8.50).

CONCLUSION

A high frequency of epilepsy-associated executive dysfunction was observed in Mataram. Higher education level was a cognitive reserve component protective against executive dysfunction in these patients.

The impact of loneliness and social adaptation on depressive symptoms: Behavioral and brain measures evidence from a brain health perspective

Introduction

Early detection of depression is a cost-effective way to prevent adverse outcomes on brain physiology, cognition, and health. Here we propose that loneliness and social adaptation are key factors that can anticipate depressive symptoms.

Methods

We analyzed data from two separate samples to evaluate the associations between loneliness, social adaptation, depressive symptoms, and their neural correlates.

Results

For both samples, hierarchical regression models on self-reported data showed that loneliness and social adaptation have negative and positive effects on depressive symptoms. Moreover, social adaptation reduces the impact of loneliness on depressive symptoms. Structural connectivity analysis showed that depressive symptoms, loneliness, and social adaptation share a common neural substrate. Furthermore, functional connectivity analysis demonstrated that only social adaptation was associated with connectivity in parietal areas.

Discussion

Altogether, our results suggest that loneliness is a strong risk factor for depressive symptoms while social adaptation acts as a buffer against the ill effects of loneliness. At the neuroanatomical level, loneliness and depression may affect the integrity of white matter structures known to be associated to emotion dysregulation and cognitive impairment. On the other hand, socio-adaptive processes may protect against the harmful effects of loneliness and depression. Structural and functional correlates of social adaptation could indicate a protective role through long and short-term effects, respectively. These findings may aid approaches to preserve brain health via social participation and adaptive social behavior.

Global cognitive function is associated with sex, educational level, occupation type, and speech recognition rate in older Chinese adults: a single-center, prospective, cross-sectional study

BACKGROUND

The development of cognitive impairment may be delayed if its risk factors are identified and detected, if its developmental trend can be predicted, and if early intervention can be performed. This study primarily aimed to investigate the association between global cognitive function and hearing loss, educational level, and occupation type and to determine any differences in such associations according to sex among older Chinese adults.

METHODS

In this cross-sectional study, we prospectively recruited 219 individuals above 55 years old in an otolaryngology outpatient clinic who could write independently and had no severe vision impairment. Audiometric examinations included otoscopy, acoustic immittance, pure-tone audiometry, and speech audiometry for each ear. Cognitive function was evaluated by using the Chinese version of the Mini-Mental State Examination (MMSE). Multivariable linear regression analyses were performed to evaluate the relationship between variables and MMSE scores after adjusting for independent variables that were statistically significant in the univariable analyses.

RESULTS

We enrolled 219 individuals: 98 men (mean ± standard deviation age, 63.08 ± 6.64 years) and 121 women (62.64 ± 7.17 years). The overall MMSE scores of the normal hearing group and the mild, moderate, and severe-to-profound hearing loss groups were 24.00 (5.00), 24.00 (5.00), 23.00 (5.00), and 23.00 (13.00), respectively. MMSE scores were higher among participants with higher educational levels (p < 0.001) and were significantly correlated with occupation type (p < 0.001). MMSE scores were significantly higher in men than in women (p < 0.001). However, after the analysis of the five subdomains, significant differences were only observed for attention and calculation (p < 0.001) and language (p = 0.011). We further compared the distribution of educational levels between men and women by using the chi-square test; there was no significant difference in educational level between the sexes (p = 0.070).

CONCLUSIONS

We reported statistically significant relationships between global cognitive function and sex, educational level, and occupation type. Sex-specific strategies may be required to improve healthcare policies.

The Nuance of Bilingualism as a Reserve Contributor: Conveying Research to the Broader Neuroscience Community

The neurological notion of "reserve" arises from an individually observable dissociation between brain health and cognitive status. According to the cognitive reserve hypothesis, high-reserve individuals experience functional compensation for neural atrophy and, thus, are able to maintain relatively stable cognitive functioning with no or smaller-than-expected impairment. Several lifestyle factors such as regular physical exercise, adequate and balanced nutrition, and educational attainment have been widely reported to contribute to reserve and, thus, lead to more successful trajectories of cognitive aging (CA). In recent years, it has become clear that bilingualism is also a potential reserve contributor. Yet, there is little communication between the neuroscience of bilingualism research community and researchers working in the field of CA more generally, despite compelling reasons for it. In fact, bilingualism tends to be overlooked as a contributory factor in the CA literature, or reduced to a dichotomous trait, despite it being a complex experience. Herein, we discuss issues that are preventing recognition of bilingualism as a reserve contributor across all literatures, highlight the benefits of including language experiences as a factor of interest across research disciplines, and suggest a roadmap to better integrate bilingualism and aging moving forward. We close with calls toward a model of aging that examines the contributions across lifestyle factors, including that of bilingual experience.

The Assessment of Cognitive Reserve: A Systematic Review of the Most Used Quantitative Measurement Methods of Cognitive Reserve for Aging

The cognitive reserve (CR) is widely accepted as the active ability to cope with brain damage, using preexisting cognitive and compensatory processes. The common CR proxies used are the number of formal years of education, intelligence quotient (IQ) or premorbid functioning, occupation attainment, and participation in leisure activities. More recently, it has employed the level of literacy and engagement in high-level cognitive demand of professional activities. This study aims to identify and summarize published methodologies to assess the CR quantitatively. We searched for published studies on PubMed, ScienceDirect, and Web of Science between September 2018 and September 2021. We only included those studies that characterized the CR assessment methodology. The search strategy identified 1,285 publications, of which 25 were included. Most of the instruments targeted proxies individually. The lack of a gold standard tool that incorporates all proxies and cognitive tests highlights the need to develop a more holistic battery for the quantitative assessment of CR. Further studies should focus on a quantitative methodology that includes all these proxies supported by normative data to improve the use of CR as a valid measure in clinical contexts.

Cognitive reserve and its correlates in child and adolescent offspring of patients diagnosed with schizophrenia or bipolar disorder

AIM

To analyze cognitive reserve (CR) in child and adolescent offspring of patients diagnosed with schizophrenia (SZ-off) or bipolar disorder (BD-off) and compare them with a group of community controls (CC-off). We also aimed to investigate whether there was an association between CR and clinical and neuropsychological variables according to group.

METHODS

The study included 46 SZ-off, 105 BD-off and 102 CC-off. All participants completed assessments regarding CR and clinical, neuropsychological and psychosocial functioning. CR was measured with a proxy based on premorbid intelligence, parental occupational level, educational attainment, developmental milestones and sociability. The clinical assessment included the Kiddie Schedule for Affective Disorders and Schizophrenia, Present and Lifetime, the Semi-structured Interview for Prodromal Syndromes, and the Global Assessment Functioning scale. The neuropsychological assessment included measures of executive functioning, attention, verbal memory, working memory and processing speed.

RESULTS

SZ-off showed a lower level of CR compared to BD-off and CC-off, while BD-off showed an intermediate level of CR between SZ-off and CC-off. Moreover, an association between higher CR and less lifetime psychopathology, fewer prodromal psychotic symptoms, higher psychosocial functioning, and a higher working memory score was observed in all groups, but it was stronger in SZ-off.

CONCLUSIONS

CR seemed to be associated with psychopathology, clinical symptoms, psychosocial functioning, and some cognitive functions. SZ-off appeared to benefit more from a higher CR, therefore it could be considered a protective factor against the development of clinical symptomatology and cognitive impairment.

Cognitive reserve proxies, Alzheimer pathologies, and cognition

This study aimed to explore the moderating effects of the frequently used cognitive reserve (CR) proxies [i.e., education, premorbid intelligence quotient (pIQ), occupational complexity (OC), and lifetime cognitive activity (LCA)] on the relationships between various in vivo Alzheimer's disease (AD) pathologies and cognition. In total, 351 [268 cognitively unimpaired (CU), 83 cognitive impaired (CI)] older adults underwent multi-modal brain imaging to measure AD pathologies and cognitive assessments, and information on CR proxies was obtained. For overall participants, only education moderated the relationship between Aβ deposition and cognition. Education, pIQ, and LCA, but not OC, showed moderating effect on the relationship between AD-signature cerebral hypometabolism and cognition. In contrast, only OC had a moderating effect on the relationship between cortical atrophy of the AD-signature regions and cognition. Such moderation effects of the CR proxies were similarly observed in CI individuals, but most of them were not in CU individuals. The findings suggest that the proposed CR proxies have different moderating effects on the relationships between specific AD pathologies and cognition.

The effects of bilingualism on hippocampal volume in ageing bilinguals

Long-term management of more than one language has been argued to contribute to changes in brain and cognition. This has been particularly well documented in older age, where bilingualism has been linked to protective effects against neurocognitive decline. Since memory difficulties are key aspects of this decline, herein we examine potential effects of bilingualism on the hippocampus, a brain structure related to memory that is particularly vulnerable to cognitive ageing. Hippocampal volume has been shown to increase as a result of second language learning and use in younger adults. However, it is unknown if this is maintained throughout the lifespan. We examine hippocampal volume and episodic memory performance in a participant sample consisting of healthy older individuals with a wide range of experiences in exposure and using a second language. Results reveal greater hippocampal volume calibrated to degree of quantified dual language use. Our results mirror those of immersive active bilingualism in younger populations, suggesting that long-term active bilingualism leads to neuroprotective effects in the hippocampus. We discuss this in the context of literature proposing bilingualism-induced brain reserve in the older age.

The Role of Gait Speed in Dementia: A Secondary Analysis from the SABE Colombia Study

INTRODUCTION

Gait speed (GS) is a predictor of negative outcomes in older adults and in those in risk to develop cognitive impairment; as such, it has been associated with dementia. Studies in Latin-American older adults showing this association are scarce. This study aimed to evaluate the relationship between GS and dementia in a representative sample of Colombian older adults.

METHODS

This study is a secondary analysis from the Survey on Health, Well-Being, and Aging, SABE (from initials in Spanish: Salud, Bienestar &amp; Envejecimiento) Colombia's survey conducted in 2015 with a sample of 23,694 elderly adults aged 60 years or older.

RESULTS

A total of 19,470 participants from the SABE Colombia survey were available for analysis. The multivariate analysis shows that dementia was associated with slow GS (PR 2.39; CI 1.91-3.01) independently to the other variables (p < 0.001). Similarly, GS as a continuous variable shows a statistically significant association with dementia in the adjusted analysis (OR 0.06; CI 0.04-0.09; p < 0.001).

CONCLUSION

Dementia was associated with slow GS. This finding provides evidence to include GS as a complementary parameter in the assessment of Colombian elderly adults.

The Frontal Assessment Battery 20 years later: normative data for a shortened version (FAB15)

OBJECTIVE

The Frontal Assessment Battery (FAB) is a neuropsychological tool largely used to assess executive functions. Prior studies found a marked ceiling effect for the prehension behavior subtest (PBT) in healthy and clinical populations. Aims of the present study were (i) to examine the psychometric properties of the FAB without the contribution of PBT and (ii) to provide normative data for a revised version of the FAB after exclusion of PBT (FAB15).

METHODS

The normative sample included 1,187 healthy participants. PBT had near-zero variance, poor content validity, and no discrimination power. Internal consistency increased when PBT was excluded. We assessed the FAB15 factorial structure, interrater, and test-retest reliabilities. Normative data  for the FAB15 were extracted through a regression-based procedure according to sex, age, and education.

RESULTS

The principal component analysis revealed a single "executive factor" or alternatively a bifactorial solution reflecting the different degree of discriminative capability vs. difficulty of the subtests. The FAB15 demonstrated excellent interrater and test-retest reliabilities. Regression analysis showed that sex (lowly educated women < lowly educated men), higher age, and lower education affected FAB15 score. Accordingly, three grids for adjustment of raw scores (men, women, and both) were constructed. The cut-off was fixed at the non-parametric outer tolerance limit on the fifth centile (9.36, 95% CI).

CONCLUSION

The observation of a ceiling effect in healthy subjects makes PBT not suitable for inclusion in a neuropsychological battery. The FAB15 may successfully replace the conventional FAB as a more severe and valid short screening tool to assess executive functioning.

Executive Function among Chilean Shellfish Divers: A Cross-Sectional Study Considering Working and Health Conditions in Artisanal Fishing

Knowledge about professional diving-related risk factors for reduced executive function is limited. We therefore evaluated the association between decompression illness and executive functioning among artisanal divers in southern Chile. The cross-sectional study included 104 male divers and 58 male non-diving fishermen from two fishing communities. Divers self-reported frequency and severity of symptoms of decompression illness. Executive function was evaluated by perseverative responses and perseverative errors in the Wisconsin Card Sorting Test. Age, alcohol consumption, and symptoms of depression were a-priori defined as potential confounders and included in linear regression models. Comparing divers and non-divers, no differences in the executive function were found. Among divers, 75% reported a history of at least mild decompression sickness. Higher frequency and severity of symptoms of decompression illness were associated with reduced executive function. Therefore, intervention strategies for artisanal divers should focus on prevention of decompression illness.

Mitigating the negative impacts of aging on cognitive function; modifiable factors associated with increasing cognitive reserve

Research suggests that social, physical, and cognitively challenging activities during lifetime, could mitigate the negative effects of aging on cognitive function. This effect is explained by the increased cognitive reserve (CR) resulting from such factors; in fact, such activities, by altering structural and functional properties of the human brain, equip one with more effective compensatory mechanisms to resist brain damage before the presentation of severe clinical symptoms. Therefore, applying appropriate modifications in one's lifestyle and activities may be effective in lowering the risk of developing dementia and cognitive dysfunction in old age, especially in brain areas that are susceptible to aging. In this paper, we are going to review relevant studies discussing the association between important modifiable factors, known as CR proxies (i.e., educational attainment, occupational complexity, physical activity, social engagement, bilingualism, leisure activities, and Mediterranean diet), and different domains of cognitive function, which are affected either in the process of healthy aging or neurodegenerative diseases.

Cognitive reserve and Alzheimer's biological continuum: clues for prediction and prevention of dementia

Cognitive reserve is originally an epidemiological concept that encompasses individual abilities to cope with changes. It is considered the result of a balance between processes of cellular damage and repair, and its description raised much interest in predicting and preventing cognitive decline in aging and Alzheimer's disease (AD). In this study, we discussed the concept of cognitive reserve considering the recent definition of AD as a biological continuum and suggest that the protection of cognitive reserve may result from efficient synaptic plasticity mechanisms. Despite pathological changes of AD appearing very early during life, long before the onset of cognitive symptoms, different variables act together to keep repair mechanisms effective guaranteeing successful aging if environmental enrichment is maintained.

Prevalence of Cognitive Frailty, Do Psychosocial-Related Factors Matter?

Cognitive frailty (CF) is a topic of growing interest with implications for the study of preventive interventions in aging. Nevertheless, little research has been done to assess the influence of psychosocial variables on the risk of CF. Our objectives were to estimate the prevalence of CF in a Spanish sample and to explore the influence of psychosocial variables in this prevalence. Physical frailty and cognitive, functional, psychosocial, and socio-demographic aspects were assessed in a sample of 285 participants over 60 years. Univariate and multivariate logistic regression models were carried out. A prevalence of 21.8% (95% CI 17.4-26.9) was established when both frail and pre-frail conditions were included, and a prevalence of 3.2% (95% CI 1.7-5.9) if only frail individuals were considered. Age, educational level, profession and psychological well-being variables significantly predicted CF. Frailty and pre-frailty are high-prevalence health conditions in older adults influenced by socio-demographic, socio-educative and affective factors.

Lower Levels of Education Are Associated with Cognitive Impairment in the Old Order Amish

BACKGROUND

Lower education has been reported to be associated with dementia. However, many studies have been done in settings where 12 years of formal education is the standard. Formal schooling in the Old Order Amish communities (OOA) ends at 8th grade which, along with their genetic homogeneity, makes it an interesting population to study the effect of education on cognitive impairment.

OBJECTIVE

The objective of this study was to examine the association of education with cognitive function in individuals from the OOA. We hypothesized that small differences in educational attainment at lower levels of formal education were associated with risk for cognitive impairment.

METHODS

Data of 2,426 individuals from the OOA aged 54-99 were analyzed. The Modified Mini-Mental State Examination (3MS-R) was used to classify participants as CI or normal. Individuals were classified into three education categories: <8, 8, and >8 years of education. To measure the association of education with cognitive status, a logistic regression model was performed adding age and sex as covariates.

RESULTS

Our results showed that individuals who attained lowest levels of education (<8 and 8) had a higher probability of becoming cognitvely impaired compared with people attending >8 years (OR = 2.96 and 1.85).

CONCLUSION

Even within a setting of low levels of formal education, small differences in educational attainment can still be associated with the risk of cognitive impairment. Given the homogeneity of the OOA, these results are less likely to be biased by differences in socioeconomic backgrounds.

Perfil cognitivo e clínico psiquiátrico de idosos atendidos em um ambulatório especializado

Objetivo: descrever o perfil cognitivo e clínico psiquiátrico de idosos provenientes da atenção primária e atendidos em um ambulatório especializado de um hospital universitário.Métodos: estudo transversal, descritivo e analítico, coletado de forma prospectiva em uma amostra da população idosa (60 anos ou mais) cadastrada na Estratégia Saúde da Família do município de Porto Alegre e atendidos em um ambulatório especializado de um hospital universitário, no período de julho de 2015 a julho de 2016. As variáveis analisadas foram sociodemográficas (sexo, idade, escolaridade), clínicas (diagnóstico psiquiátrico) e avaliação cognitiva (Exame Cognitivo Addenbrooke – versão revisada, ACE-R). O protocolo de pesquisa foi aprovado pelos Comitês de Ética em Pesquisa e todos os participantes assinaram o Termo de Consentimento Livre e Esclarecido.Resultados: foram avaliados 256 indivíduos com média de idade de 70,8±7,1 anos, na maioria mulheres (77,7%) e com 4 a 7 anos de estudo (32,2%). Desses, 54,3% apresentavam alguma alteração cognitiva e 43,4% eram classificados como tendo demência, através da avaliação do ACE-R.Conclusões: o perfil cognitivo e clínico psiquiátrico dos participantes do estudo demostrou que, no grupo normal, os idosos eram mais jovens e com maior escolaridade e, no grupo demência, os indivíduos eram mais velhos, com menor escolaridade e com diagnóstico de depressão

Active bilingualism delays the onset of mild cognitive impairment

Lifelong bilingualism may contribute to cognitive reserve (CR) in neurodegenerative diseases as shown by a delay of the age at symptom onset in bilinguals with Alzheimer's disease (AD) and Mild Cognitive Impairment (MCI). However, some studies have failed to show this bilingual advantage, suggesting that it might depend on the type and degree of bilingualism. In the present study, we tested the hypothesis that active bilingualism, defined as the continuous use of the two languages as opposed to second language exposition only, may protect against cognitive decline. Moreover, we investigated whether bilingualism as a CR factor may be explained by an advantage within the executive control (EC) system. To do so, we collected clinical measures (age at onset of cognitive symptoms, age at the first medical visit for cognitive impairments, and age at diagnosis) in patients with MCI and patients with AD with different degrees of language experience and usage of Catalan and Spanish. Additionally, all participants were tested on four EC tasks and one long-term memory recognition task. First, results from multiple regression analyses showed that active bilingualism was a significant predictor of delay in the age at onset for all the clinical measures in MCI, but not AD patients. Second, the effect of active bilingualism was independent of occupation, educational level and job attainment across the individuals' lifespan. Finally, although we did not find an effect of active bilingualism across all EC tasks, we did find an effect for conflict resolution. These results are discussed in the context of CR hypotheses, suggesting that compensatory mechanisms may play a role in protecting against cognitive decline.

Time for a Systems Biological Approach to Cognitive Aging?-A Critical Review

The underlying premise of current theories of cognitive decline with age tend to be primarily cognitive or biological explanations, with relatively few theories adequately integrating both aspects. Though literature has also emphasized the importance of several factors that contribute to cognitive aging including: (a) decline in sensory abilities; (b) the effect of motor speed on paper-pencil measures of cognitive speed; (c) the impact of level of education and physical activity; and (d) molecular biological changes that occur with age, these factors have seldom been implicated into any single theoretical model of cognitive aging. Indeed, such an integrated bio-cognitive model of aging has the potential to provide a more comprehensive understanding of attention, perception, learning, and memory across the lifespan. Thus, the aim of this review was to critically evaluate common theories of age-related cognitive decline and highlight the need for a more comprehensive systems neuroscience approach to cognitive aging.

Relación del nivel ocupacional, funcionamiento cognitivo y satisfacción vital en mayores de 55 años

El progresivo envejecimiento de la población obliga a las administraciones con competencias en materia sanitaria a intervenir en los efectos adversos de la falta de actividad física o funcional (depresión, ansiedad, deterioro cognitivo e insatisfacción vital, entre otros). El objetivo de este estudio es comprobar si el nivel de ocupación en actividades básicas de la vida cotidiana u ocio de una muestra de personas mayores de 55 años tiene influencia sobre el grado de funcionamiento cognitivo y su satisfacción vital. Se trata de un estudio transversal, con un muestreo no probabilístico por conveniencia, desarrollado con 302 personas mayores de 55 años de varios centros participación activa (CPA) de la provincia de Almería (España). Los instrumentos utilizados para la valoración comprendieron el Mini-Exámen Cognoscitivo, la Escala de Satisfacción de Filadelfia y el Cuestionario de Conducta Ocupacional de Mayores (C-COM). El análisis multigrupo de los datos también incluyó un modelo estructural mediante path analysis. Los resultados han verificado la influencia de la ocupación en el deterioro cognitivo y la satisfacción vital, tanto en hombres como en mujeres. Las actividades de ocio aportan una mayor satisfacción vital que las ocupaciones del quehacer diario. La actitud hacia el envejecimiento ha sido el factor que ha arrojado una mayor correlación con el nivel ocupacional de la persona. Los datos respaldan la necesidad de unas recomendaciones adecuadas para el diseño de programas específicos que favorezcan intervenciones individuales y colectivas enfocadas al ejercicio, la prevención del deterioro cognitivo y el fomento de la satisfacción vital.

Lifespan Intellectual Factors, Genetic Susceptibility, and Cognitive Phenotypes in Aging: Implications for Interventions

Along with rapid global population aging, the age-related cognitive disorders such as mild cognitive impairment (MCI) and dementia have posed a serious threat to public health, health care system, and sustainable economic and societal development of all countries. In this narrative review, we seek to summarize the major epidemiological studies from the life-course perspective that investigate the influence of genetic susceptibility [e.g., apolipoprotein (APOE) ε4 allele] and intellectual or psychosocial factors (e.g., educational attainments and leisure activities) as well as their interactions on cognitive phenotypes in aging. Numerous population-based studies have suggested that early-life educational attainments and socioeconomic status, midlife work complexity and social engagements, late-life leisure activities (social, physical, and mentally-stimulating activities), certain personality traits (e.g., high neuroticism and low conscientiousness), and depression significantly affect late-life cognitive phenotypes. Furthermore, certain intellectual or psychosocial factors (e.g., leisure activities and depression) may interact with genetic susceptibility (e.g., APOE ε4 allele) to affect the phenotypes of cognitive aging such that risk or beneficial effects of these factors on cognitive function may vary by carrying the susceptibility genes. Current evidence from the randomized controlled trials that support the cognitive benefits of cognitive training among cognitive healthy older adults remains limited. The cognitive reserve hypothesis has been proposed to partly explain the beneficial effects of lifetime intellectual and psychosocial factors on late-life cognitive function. This implies that, from a life-course perspective, preventive intervention strategies targeting multiple modifiable intellectual and psychosocial factors could interfere with clinical expression of cognitive disorders in old age and delay the onset of dementia syndrome, and thus, may help achieve healthy brain aging.

Newly Generated and Non-Newly Generated "Immature" Neurons in the Mammalian Brain: A Possible Reservoir of Young Cells to Prevent Brain Aging and Disease?

Brain plasticity is important for translational purposes since most neurological disorders and brain aging problems remain substantially incurable. In the mammalian nervous system, neurons are mostly not renewed throughout life and cannot be replaced. In humans, the increasing life expectancy explains the increase in brain health problems, also producing heavy social and economic burden. An exception to the “static” brain is represented by stem cell niches leading to the production of new neurons. Such adult neurogenesis is dramatically reduced from fish to mammals, and in large-brained mammals with respect to rodents. Some examples of neurogenesis occurring outside the neurogenic niches have been reported, yet these new neurons actually do not integrate in the mature nervous tissue. Non-newly generated, “immature” neurons (nng-INs) are also present: Prenatally generated cells continuing to express molecules of immaturity (mostly shared with the newly born neurons). Of interest, nng-INs seem to show an inverse phylogenetic trend across mammals, being abundant in higher-order brain regions not served by neurogenesis and providing structural plasticity in rather stable areas. Both newly generated and nng-INs represent a potential reservoir of young cells (a “brain reserve”) that might be exploited for preventing the damage of aging and/or delay the onset/reduce the impact of neurological disorders.