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Objective: this study investigates the role of social and mental occupational characteristics in cognitive decline after
Methods: the study included 1,048 subjects aged ≥65 years from the Three City cohort. Participants were evaluated at
home at the initial visit and at 2-year intervals for a period of 12 years. The study includes detailed assessments of cognition,
health and information about the subjects’ main occupation. The four cognitive tests have been grouped into one latent factor.
Three independent raters specialised in employment were asked to evaluate the level of social and intellectual stimulation
for each occupation, which was then rated as low, medium and high.
Results: after controlling for potential confounding factors, no association was found between higher levels of social stimulation
at work and baseline cognition (medium score, P = 0.440; high score, P = 0.700) as compared with a low level. While
cognitive trajectories were initially similar between high and medium levels of social stimulation compared with that of a low
level, with advancing age this association diverged whereby more social stimulation during work years was related to accelerated
cognitive decline that further grew in magnitude with older age. For mental stimulation, differences were only observed at baseline,
with greater levels of mental stimulation during work years being associated with better cognitive performance (medium
score, β = 0.573, P = 0.015; and high score, β = 0.510; P = 0.090) compared with a low level of mental stimulation.
Conclusion: workers retiring from occupations characterised by high levels of social stimulation may be at risk of accelerated
cognitive decline with advancing age.
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... The following sociodemographic variables were studied: gender, age, level of education, civil status, and mental occupational, physical occupational, and clinical states, such as high blood pressure (HBP), diabetes, hypercholesterolemia, obesity, and cerebrovascular accidents (CVA). Moreover, an analysis of the subgroups was considered according to the level of education (primary/higher), physical occupational status and mental occupational status based on three levels: low, medium, and high (for each) . ...
... When analyzing the occupational elements, our study revealed that men developed mental capacities when they worked better than women. Similar results were reported by other authors, who demonstrated that those occupations involving higher mental demands enhance cognitive functioning, which may come over as better cognitive performance after retirement in older adults [21,33]. Mental demand has been considered a factor that protects older adults from functional loss . ...
Older adults are particularly vulnerable to cognitive impairment with age, and gender differences are remarkable. However, there is very little evidence to identify both baseline cognitive and occupational gender differences prior to older adults’ retirement to design more efficient personalized cognitive interventions. This descriptive observational study examined gender differences in initial cognitive performance in 367 older adults with subjective memory complaints from a primary healthcare center in Zaragoza (Spain). To evaluate initial cognitive performance, the Spanish version of the Mini-Mental State Examination (MEC-35) and the set test were used to measure verbal fluency. Sociodemographic and clinical characteristics were evaluated, and cognitive and occupational differences were analyzed per gender. Men had higher educational and occupational levels, were older and more of them were married (p < 0.001) than women. Regarding cardiovascular risk factors, diabetes and cerebrovascular accidents were more frequent in women, while hypercholesterolemia and obesity were more frequent in men (p < 0.001). High blood pressure was more frequent in women, but not significantly so (p = 0.639). Global cognition was higher in men (p < 0.001) for attention, calculation, and language (p < 0.001). Verbal fluency was higher in women, but the difference was not statistically significant (p = 0.105). These results could be generalized to other health centers in the province and other Spanish autonomous communities as their sociodemographic variables are similar. Individualized interventions that adapt to gender, cognitive and initial occupational performance should be developed and adapted to elderly populations living in the general community to maintain their cognitive capacity and prevent their cognitive impairment and the social health costs this would imply.
... The following socio-demographic variables were studied: gender, age, level of education, marital status, and mental occupational, physical occupational, and clinical statuses such as AHT, diabetes, hypercholesterolemia, obesity, and CVA. An analysis of the subgroups was considered according to both the physical occupational and mental occupational statuses based on three levels for each one: low, medium, high . The presence of SMC was evaluated by the question: Do you have complaints about your memory? ...
Introduction: Successful aging lies in cognitive and functional maintenance, and in the optimal performance of daily tasks that keep the elderly free of disability and dependence. However, there is little evidence for functional differences for gender and age, and how cognitive and physical demands in past working lives can affect them, to design more personalized occupational therapy interventions to prevent functional and cognitive impairment. Method: This observational descriptive study evaluated 367 older adults living in a community with subjective memory complaints and scored between 24 and 35 with the Spanish version of the “Mini-Mental State Examination (MEC-35)”. Basic activities of daily living (BADL) were studied with the Barthel Index, while instrumental ADL (IADL) were examined with the Lawton–Brody scale. Functional differences for gender, age, and physico-mental occupation were examined. Results: The significant differences found for gender indicated that men did better in BADL (p = 0.026) and women better performed IADL (p < 0.001). Differences between age groups suggest that the younger group (aged 64–75) obtained better results for BADL (p = 0.001) and IADL (p < 0.001). For physico-mental occupation, statistically significant differences were found only in IADL for mental (p = 0.034) and physical occupation (p = 0.005). Conclusions: Gender, age, and the cognitive and physical demands of occupational stages, can be important predictors of cognitive and functional impairment. These results can be generalized to other health centers in the province and to other Spanish Autonomous Communities because their socio-demographic variables are similar. It would be interesting to carry out multimodal personalized interventions that consider the factors that might affect functional impairment to preserve personal autonomy.
... Although employment can provide older persons with an opportunity for intellectual engagement, this may be dependent on the type of occupation and the mental stimulation involved (Grotz et al. 2018). In turn, intellectual engagement may be important for maintaining cognitive ability to make sound future investment and consumption decisions and detect attempts at fraud. ...
Population studies show the importance of active aging for maintaining cognitive health, but much of the research has focused on episodic memory and verbal skills. Aging and ability to make rational intertemporal financial decisions is less understood, despite its critical role in consumer finance. This study describes the relationship between age, retirement and intertemporal decision ability. A survey of adults examines the interplay of aging and retirement related to completing simple calculations with time tradeoffs in benefits. A negative association between intertemporal skills and age is indicated, with a sharp downward inflection around age 66. Regression analysis results in a significant, negative retirement‐age interaction term. This research has implications for policy and consumer decision‐making. The negative relationship of age and retirement status may suggest limits to career extension, or alternatively, that extending some types of careers could provide cognitive benefits. Further research is needed to understand the direction of causality.
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... On the other hand, a differential preservation pattern shows that, at the time of retirement, individuals with higher complexity of work exhibit higher cognitive performance than those with lower complexity of work and show reduced decline compared with those retiring from less-complex jobs. In terms of types of complexity, higher complexity of work with people has been associated with a faster rate of decline after retirement more consistently, although complexity of work with data shows similar patterns (Finkel et al., 2009;Grotz et al., 2018). Studies that applied an overall measure of complexity without differentiating between the three types of complexity (i.e., data, people, and things) found that higher-complex jobs were associated with slower cognitive aging (Fisher et al., 2014) and lower risk of cognitive impairment Boots et al., 2015) post-retirement. ...
Retirement has been associated with cognitive decline. However, the influence of specific job characteristics like occupational complexity on post-retirement cognitive outcomes is not well understood. Data from the Midlife in the United States (MIDUS) study were used to examine occupational complexity in relation to cognitive performance and cognitive change after retirement. Initial sample included 471 workers between 45 and 75 years of age. At 9-year follow-up (T2), 149 were retired and 322 were still working. All six tasks from the Brief Test of Adult Cognition by Telephone (BTACT) were used. Hierarchical regression with workers at T1 indicated that, controlling for sociodemographic variables, complexity of work with people significantly contributed to explaining variance in overall cognitive performance (1.7%) and executive function (2%). In Latent Change Score (LCS) models, complexity of work with people was the only significant predictor of cognitive change in retirees, with those retiring from high-complexity jobs showing less decline. In conclusion, high complexity of work with people is related to better executive functioning and overall cognition during working life and slower decline after retirement. The finding that more intellectually stimulating work carries cognitive advantage into retirement fits the cognitive reserve concept, where earlier intellectual stimulation brings about lower risks of cognitive problems later. Study results also go along with the unengaged lifestyle hypothesis, whereby people may slip into so-called "mental retirement," leading to post-retirement cognitive loss, which may be most apparent among those retiring from jobs with low complexity of work with people. (PsycInfo Database Record (c) 2021 APA, all rights reserved).
... A c c e p t e d M a n u s c r i p t Occupation is often a major source of a person's mentally challenging activities during adulthood; therefore the nature of work tasks during midlife may afford protections or confer risks for long-term brain health (Nexø, Meng, & Borg, 2016;Then et al., 2013). Although it is relatively well-established that engaging in cognitively stimulating activities in the workplace is associated with higher levels of cognition (Opdebeeck, Martyr, & Clare, 2016;Then et al., 2013), conflicting results have been reported in the association of mentally stimulating activities with rates of cognitive change, with some studies showing slower cognitive decline (Fisher et al., 2014;Marquié et al., 2010;Pool et al., 2016;Then et al., 2015), others reporting more rapid decline (Singh-Manoux Archana et al., 2011), and other studies showing no significant association (Gow, Avlund, & Mortensen, 2012;Grotz et al., 2017). In the current study, we investigate the rates of cognitive decline in late life associated with working in mentally challenging occupations. ...
Engaging in mentally challenging activities is associated with reduced risk for cognitive impairment and dementia; however, its association with rates of cognitive decline has been inconsistent. The aim of this study is to test whether working in mentally challenging occupations is related to rates of cognitive change at later older adulthood.
The sample consisted of 1,520 individuals (baseline mean age=78.6±5.1, range=64 to 100) from the Einstein Aging Study. Occupation information of each participant was collected retrospectively and linked with the substantive complexity of work score from the Dictionary of Occupational Titles. Cognitive changes in memory, speed, and executive function (EF) domains were represented using two time metrics (i.e., time from retirement, time from study enrollment).
Results from mixed models showed that occupational complexity was associated with significantly faster rates of cognitive decline in speed and EF in the "time from retirement" model but not in the "time from baseline" model. Despite faster cognitive loss, the protective effect of occupational complexity persisted for decades after retirement due to higher initial levels of cognition.
The result suggests that protective factors for cognitive health may be associated with delayed onset but more rapid cognitive decline afterwards at later stages of cognitive aging.
Late-life cognitive decline ranges from the mildest cases of normal, age-related change to mild cognitive impairment to severe cases of dementia. Dementia is the largest global burden for the 21 st century welfare and healthcare systems. The aim of this study was to analyze the neuropsychological constructs (temporal orientation (TO), spatial orientation (SO), fixation memory (FM), attention (A), calculation (C), short-term memory (STM), language (L), and praxis (P)), semantic fluency, level of functionality, and mood that reveal the greatest deficit in the different stages ranging from normal cognition (NC) to cognitive impairment in older adults in a primary healthcare setting. The study included 337 participants (102 men, 235 women), having a mean age of 74 ± 6 years. According to their scores on the Spanish version of the Mini-Mental State Examination (MEC-35), subjects were divided into 4 groups: no deterioration (ND) (score 32–35), subtle cognitive impairment (SCI) (score 28–31), level deterioration (LD) (score 24–27) and moderate deterioration (MD) (score 20–23). The ND group revealed significant differences in TO, STM, C, A, L, P, and S-T as compared to the other groups. The MD group (in all the neuropsychological constructs) and the ND and SCI groups showed significant differences on the Yesavage geriatric depression scale (GDS-15). All except the FM neuropsychological construct were part of the MEC-35 prediction model and all of the regression coefficients were significant for these variables in the model. Furthermore, the highest average percentage of relative deterioration occurs between LD and MD and the greatest deterioration is observed in the STM for all groups, including A and TO for the LD and MD groups. Based on our findings, community programs have been implemented that use cognitive stimulation to prevent cognitive decline and to maintain the neuropsychological constructs.
RESUMO Objetivo: Revisar sistematicamente evidências dos aspectos cognitivos da pessoa idosa relacionados à aposentadoria. Métodos: A busca foi realizada em dez bases de dados: Bireme (BVS), Ebsco, Eric, Oxfford Journals, Scielo, Lilacs, PsycINFO, Scopus, ScienceDirect e Web of Science. Foram selecionados artigos de observação relacionados à cognição e à aposentadoria de pessoas com 60 anos ou mais, publicados no período de janeiro de 2010 a abril de 2020. A qualidade dos artigos foi verificada por dois revisores independentes por meio do Strengthening the Reporting of Observational Studies in Epidemiology-STROBE. Resultados: Sete estudos preencheram os critérios de inclusão, dentre os quais, quatro artigos abordaram a cognição relacionada à complexidade do trabalho; um artigo analisou a cognição a partir da relação entre trabalhadores pagos, aposentados e donas de casa; um artigo analisou a cognição de aposentados empregados e não empregados; e um artigo analisou o desempenho cognitivo em idosos observando a maneira como estes consideraram o trabalho que exerciam e sua adaptação a vida pós-aposentadoria. Considerações finais: As características do emprego são preditores importantes para a saúde mental dos trabalhadores antes e após a aposentadoria, especialmente quando se relaciona o desempenho cognitivo com a maior complexidade do trabalho com dados. ABSTRACT Objective: To review systematically the evidence of the elderly cognitive aspects related to the retirement. Methods: The search was carried out in ten databases: Bireme (BVS), Ebsco, Eric, Oxfford Journals, Scielo, Lilacs, PsycINFO, Scopus, ScienceDirect and Web of Science. Were selected observational articles related to cognition and retirement of people aged 60 and over, published between January 2010 and April 2020. The quality of the articles was verified by two independent reviewers through the Strengthening the Reporting of Observational Studies in Epidemiology guideline (STROBE). Results: Seven studies filled up the inclusion criteria among which four articles addressed cognition related to the complexity of work. An article analyzed cognition from the relationship between paid workers, retirees and housewives; an article analyzed the cognition of retirees employed and non-employed and an article analyzed the cognitive performance in the elderly, observing how they considered their work and their adaptation to post-retirement life. Final considerations: Job characteristics are important predictors for workers' mental health before and after retirement, especially when cognitive performance is related to the greater complexity of working with data.
Objetivo: Revisar sistematicamente evidências dos aspectos cognitivos da pessoa idosa relacionados à aposentadoria. Métodos: A busca foi realizada em dez bases de dados: Bireme (BVS), Ebsco, Eric, Oxfford Journals, Scielo, Lilacs, PsycINFO, Scopus, ScienceDirect e Web of Science. Foram selecionados artigos de observação relacionados à cognição e à aposentadoria de pessoas com 60 anos ou mais, publicados no período de janeiro de 2010 a abril de 2020. A qualidade dos artigos foi verificada por dois revisores independentes por meio do Strengthening the Reporting of Observational Studies in Epidemiology – STROBE. Resultados: Sete estudos preencheram os critérios de inclusão, dentre os quais, quatro artigos abordaram a cognição relacionada à complexidade do trabalho; um artigo analisou a cognição a partir da relação entre trabalhadores pagos, aposentados e donas de casa; um artigo analisou a cognição de aposentados empregados e não empregados; e um artigo analisou o desempenho cognitivo em idosos observando a maneira como estes consideraram o trabalho que exerciam e sua adaptação a vida pós-aposentadoria. Considerações finais: As características do emprego são preditores importantes para a saúde mental dos trabalhadores antes e após a aposentadoria, especialmente quando se relaciona o desempenho cognitivo com a maior complexidade do trabalho com dados.
Identifying modifiable lifestyle correlates of cognitive decline and risk of dementia is complex, particularly as few population-based longitudinal studies jointly model these interlinked processes. Recent methodological developments allow us to examine statistically defined sub-populations with separate cognitive trajectories and dementia risks.
Engagement in social, physical, or intellectual pursuits, social network size, self-perception of feeling well understood, and degree of satisfaction with social relationships were assessed in 2854 participants from the Paquid cohort (mean baseline age 77 years) and related to incident dementia and cognitive change over 20-years of follow-up. Multivariate repeated cognitive information was exploited by defining the global cognitive functioning as the latent common factor underlying the tests. In addition, three latent homogeneous sub-populations of cognitive change and dementia were identified and contrasted according to social environment variables.
In the whole population, we found associations between increased engagement in social, physical, or intellectual pursuits and increased cognitive ability (but not decline) and decreased risk of incident dementia, and between feeling understood and slower cognitive decline. There was evidence for three sub-populations of cognitive aging: fast, medium, and no cognitive decline. The social-environment measures at baseline did not help explain the heterogeneity of cognitive decline and incident dementia diagnosis between these sub-populations.
We observed a complex series of relationships between social-environment variables and cognitive decline and dementia. In the whole population, factors such as increased engagement in social, physical, or intellectual pursuits were related to a decreased risk of dementia. However, in a sub-population analysis, the social-environment variables were not linked to the heterogeneous patterns of cognitive decline and dementia risk that defined the sub-groups.
To determine whether and how age at retirement influences the risk of dementia. The association between the age at retirement, the number of working years and the risk of dementia was evaluated over 12 years of follow-up.
A prospective population-based study.
Three-City cohort, a French population-based study of community-dwelling individuals aged 65 to 95.
The sample consisted of 1,658 non-demented participants at baseline.
All participants were evaluated at home at the initial visit and at two years interval for a period of 12 years. An active research of dementia was conducted at each follow-up; all suspected cases were analysed by an independent committee of neurologists. Information regarding retirement age and number of working years was collected at baseline using a structured questionnaire.
The multivariate Cox model, including both the age at retirement and the number of working years and adjusted for potential confounders, revealed that the risk of dementia was independently associated with the age at retirement (p=0.022) but not with the number of working years (p=0.296).
Although our results are in accordance with previous studies (i.e., older age at retirement is associated with decreased risk of dementia), it provides additional information regarding the possible explanation for such results. Given that a longer working life did not reduce the risk of dementia, the age at retirement cannot be considered as a new factor of cognitive reserve but rather seems to be a psycho-social vulnerability factor. Further evidence is necessary to identify work and retirement related factors that influence the association between the age at retirement and the risk of dementia.
This paper investigates the relationship between the concept of activity (including both professional and nonprofessional) and cognitive functioning among older European individuals. In this research, we used data collected during the first wave of SHARE (Survey on Health, Ageing and Retirement in Europe), and a measurement approach known as stochastic frontier analysis, derived from the economic literature. SHARE includes a large population (n > 25,000) geographically distributed across Europe, and analyzes several dimensions simultaneously, including physical and mental health activity. The main advantages of stochastic frontier analysis are that it allows estimation of parametric function relating cognitive scores and driving factors at the boundary and disentangles frontier noise and distance to frontier components, as well as testing the effect of potential factors on these distances simultaneously. The analysis reveals that all activities are positively related to cognitive functioning in elderly people. Our results are discussed in terms of prevention of cognitive aging and Alzheimer's disease, and regarding the potential impact that some retirement programs might have on cognitive functioning in individuals across Europe.
We investigate the relationship between aging, cognitive abilities and retirement using the Survey on Health, Aging and Retirement in Europe (SHARE), a household panel that offers the possibility of comparing several European countries using nationally representative samples of the population aged 50+. We use a version of the model proposed by Grossman (1972) as a guide for our empirical specification of the age-profile of cognitive abilities. According to the model, retirement plays a fundamental role in explaining the process of cognitive deterioration. Our empirical results confirm this key prediction. They also indicate that education plays a fundamental role in explaining heterogeneity in the level of cognitive abilities.
We used data from SWEOLD, a Swedish nationally representative study of individuals aged 77 years or older, to examine midlife indicators of job strain in relation to cognitive performance and impairment.
In all, 827 participants completed an abridged 11-point version of the Mini-Mental State Examination in-person in 1992 and/or 2002 and had self-reported and/or occupation-based scores for job control and demands from data collected in 1968. Seventeen percent scored below the cutoff for cognitive impairment.
Controlling for age, sex, education, self-rated health, and year of cognitive screening, low self-reported and occupation-based job control at midlife was associated with poorer cognitive performance later (ps < .001). For the occupation-based measure, low job control was also associated with greater likelihood of impairment, whereas having an active job (high job control/high job demands) was associated with better cognitive performance and lower likelihood of impairment (ps < .01). Childhood environment, midlife depressive symptoms, and social activity had limited influence, whereas the influence of both adulthood socioeconomic position and work complexity on these results was more pronounced.
Job control at midlife, by itself and in combination with job demands, may influence cognitive functioning later above and beyond demographic variables and other occupational characteristics.
Some studies suggest that people can maintain their cognitive abilities through "mental exercise." This has not been unequivocally proven. Retirement is associated with a large change in a person's daily routine and environment. In this paper, we propose two mechanisms how retirement may lead to cognitive decline. For many people retirement leads to a less stimulating daily environment. In addition, the prospect of retirement reduces the incentive to engage in mentally stimulating activities on the job. We investigate the effect of retirement on cognition empirically using cross-nationally comparable surveys of older persons in the United States, England, and 11 European countries in 2004. We find that early retirement has a significant negative impact on the cognitive ability of people in their early 60s that is both quantitatively important and causal. Identification is achieved using national pension policies as instruments for endogenous retirement.
We examined the association between complexity of the main lifetime occupation and changes in cognitive ability in later life. Data on complexity of work with data, people, and things and on 4 cognitive factors (verbal, spatial, memory, and speed) were available from 462 individuals in the longitudinal Swedish Adoption/Twin Study of Aging. Mean age at the first measurement wave was 64.3 years (SD = 7.2), and 65% of the sample had participated in at least three waves of data collection. Occupational complexity with people and data were both correlated with cognitive performance. Individuals with more complex work demonstrated higher mean performance on the verbal, spatial, and speed factors. Latent growth curve analyses indicated that, after correcting for education, only complexity with people was associated with differences in cognitive performance and rate of cognitive change. Continued engagement as a result of occupational complexity with people helped to facilitate verbal function before retirement, whereas a previous high level of complexity of work with people was associated with faster decline after retirement on the spatial factor.
Enhanced cued recall provides a simple and clinically useful memory test for identifying dementia in the elderly. Because this test induces semantic processing and coordinates encoding and retrieval for maximum recall, genuine memory deficits due to impairment of specific memory processes can be distinguished from apparent memory deficits due to use of inefficient strategies or impairment of other cognitive processes. Since genuine memory deficits in the elderly are usually associated with dementia, their identification is highly predictive of clinical dementia. The present study validates the use of enhanced cued recall as a screening test for dementia in 70 aged subjects. All but one person with a pure amnesia were correctly classified. Enhanced cued recall correctly classified 97% of the 120 subjects in this and the previous study. Enhanced cued recall shows learning not revealed by free recall, providing more accurate measurement of memory, and distinguishes demented from nondemented elderly more accurately than either free recall or recognition.
The idea of reserve against brain damage stems from the repeated observation that there does not appear to be a direct relationship between the degree of brain pathology or brain damage and the clinical manifestation of that damage. This paper attempts to develop a coherent theoretical account of reserve. One convenient subdivision of reserve models revolves around whether they envision reserve as a passive process, such as in brain reserve or threshold, or see the brain as actively attempting to cope with or compensate for pathology, as in cognitive reserve. Cognitive reserve may be based on more efficient utilization of brain networks or of enhanced ability to recruit alternate brain networks as needed. A distinction is suggested between reserve, the ability to optimize or maximize normal performance, and compensation, an attempt to maximize performance in the face of brain damage by using brain structures or networks not engaged when the brain is not damaged. Epidemiologic and imaging data that help to develop and support the concept of reserve are presented.
We examined the association between risk of dementia or Alzheimer's disease (AD) and occupation by using measures of complexity
of work with data, people, and things. The study included 10,079 members of the population-based Swedish Twin Registry who
were participants in the HARMONY study. We diagnosed dementia by means of a two-stage procedure—cognitive impairment screening
followed by full clinical evaluation. We analyzed data with case-control and cotwin control designs. The cotwin control design
provides control over genetic and familial factors. In the case-control study, controlling for age, gender, and level of education,
we found that more complex work with people was associated with reduced risk of AD. Greater complexity of work with people
and data was protective in twin pairs discordant for AD. Findings suggest that greater complexity of work, and particularly
complex work with people, may reduce the risk of AD.
The authors explored the association between complexity of primary lifetime occupation and cognition in older adulthood.
The study included 386 participants from the Swedish Panel Study of Living Conditions of the Oldest Old, a nationally representative sample aged 77 years or older. The authors examined complexity of work with data, people, and things in relation to cognitive functioning, measured with a shortened version of Mini-Mental State Examination (MMSE) and cognitive impairment based on MMSE score cutoff.
Complexity of work with data and people were associated with better MMSE scores, controlling for age, sex, childhood socioeconomic status, and education. The association between complexity of work with data and MMSE remained statistically significant when adult occupational status was substituted for education as a covariate.
Complexity of primary lifetime occupation may be reflected in cognitive functioning even in advanced old age. This effect may be independent of education or occupational status.
The authors evaluated the association of complexity of work with data, people, and things with the incidence of dementia, Alzheimer's disease, and vascular dementia in the Canadian Study of Health and Aging, while adjusting for work-related physical activity. The Canadian Study of Health and Aging is a 10-year population study, from 1991 to 2001, of a representative sample of persons aged 65 years or older. Lifetime job history allowed application of complexity scores and classification of work-related physical activity. Analyses included 3,557 subjects, of whom 400 were incident dementia cases, including 299 with Alzheimer's disease and 93 with vascular dementia. In fully adjusted Cox regression models, high complexity of work with people or things reduced risk of dementia (hazard ratios were 0.66 (95% confidence interval: 0.44, 0.98) and 0.72 (95% confidence interval: 0.52, 0.99), respectively) but not Alzheimer's disease. For vascular dementia, hazard ratios were 0.36 (95% confidence interval: 0.15, 0.90) for high complexity of work with people and 0.50 (95% confidence interval: 0.25, 1.00) for high complexity of work with things. Subgroup analyses according to median duration (23 years) of principal occupation showed that associations with complexity varied according to duration of employment. High complexity of work appears to be associated with risk of dementia, but effects may vary according to subtype.
To investigate the relationship between psychological transition and adjustment to retirement and cognitive performances in older adults.
The study's sample was taken from the Approche Multidisciplinaire Intégrée cohort, a French prospective study of retirees from agriculture, aged 65 and over, living in rural settings in southwestern France. The cross-sectional analyses were conducted on a sample of 590 elderly people without dementia at baseline and for whom information on perception of the work setting, experience of the retirement transition and adaptation to retirement life (nine variables) as well as neuropsychological measures (global cognitive functioning, episodic memory, verbal fluency, attention and psychomotor speed) were available at first visit.
Multivariable linear regression analyses, including nine variables related to retirement and adjusted for potential confounding factors, indicated that three of them - positive consideration of former work situation, development of new activities during retirement and good adaptation to free time - were associated with better cognitive performances.
We found that several factors proved to be determinants of good cognitive functioning at retirement and could serve as a basis for the development of more efficient intervention programs aimed at helping retirees to maintain good cognitive functioning after retirement.
The recent availability of longitudinal data on the possible association of different lifestyles with dementia and Alzheimer's disease (AD) allow some preliminary conclusions on this topic. This review systematically analyses the published longitudinal studies exploring the effect of social network, physical leisure, and non-physical activity on cognition and dementia and then summarises the current evidence taking into account the limitations of the studies and the biological plausibility. For all three lifestyle components (social, mental, and physical), a beneficial effect on cognition and a protective effect against dementia are suggested. The three components seem to have common pathways, rather than specific mechanisms, which might converge within three major aetiological hypotheses for dementia and AD: the cognitive reserve hypothesis, the vascular hypothesis, and the stress hypothesis. Taking into account the accumulated evidence and the biological plausibility of these hypotheses, we conclude that an active and socially integrated lifestyle in late life protects against dementia and AD. Further research is necessary to better define the mechanisms of these associations and better delineate preventive and therapeutic strategies.
Objective: To describe the baseline characteristics of the participants in the Three-City (3C) Study, a study aiming to evaluate the risk of dementia and cognitive impairment attributable to vascular factors. Methods: Between 1999 and 2001, 9,693 persons aged 65 years and over, institutionalized, were recruited from the electoral rolls of three French cities, i.e. Bordeaux, Dijon and Montpellier. Health-related data were collected during face-to-face interviews using standardized questionnaires. The baseline examination included cognitive testing and diagnosis of dementia, and assessment of vascular risk factors, including blood pressure measurements, ultrasound examination of the carotid arteries, and measurement of biological parameters (glycemia, total, high-density lipoprotein and low-density lipoprotein cholesterol, triglycerides, creatinemia); 3,442 magnetic resonance imaging (MRI) examinations were performed in subjects aged 65-79. Measurements of ultrasound, blood, and MRI parameters were centralized. Two follow-up examinations (at 2 and 4 years) were planned. Results: After exclusion of the participants who had subsequently refused the medical interview, the 3C Study sample consisted of 3,649 men (39.3%) and 5,645 women, mean age 74.4 years, with a relatively high level of education and income. Forty-two percent of the participants reported to be followed up for hypertension, about one third for hypercholesterolemia, and 8% for diabetes; 65% had elevated blood pressure measures (systolic blood pressure greater than or equal to 140 or diastolic blood pressure greater than or equal to 90). The proportion of Mini-Mental State Examination scores below 24 was 7% and dementia was diagnosed in 2.2% of the participants. Conclusion: Distribution of baseline characteristics of the 3C Study participants suggests that this study will provide a unique opportunity to estimate the risk of dementia attributable to vascular factors. Copyright (C) 2003 S. Karger AG, Basel.
This paper analyses the effect of retirement on cognitive functioning using a longitudinal survey among older Americans, which allows controlling for individual heterogeneity and endogeneity of the retirement decision by using the eligibility age for social security as an instrument. The results highlight a significant negative effect of retirement on cognitive functioning. Our findings suggest that reforms aimed at promoting labour force participation at an older age may not only ensure the sustainability of social security systems but may also create positive health externalities for older individuals.
As part of a 5-year, prospective, epidemiological survey of normal and pathological ageing, this cross-sectional analysis examines the relationship between depressive symptomatology (CES-D) and cognitive functioning (MMS) in a community sample of 2792 non-institutionalized persons (age ≥ 65) living in Southwest France. Of the sample, 13·4%, report depressive symptoms above the cut-off. A significant association was found between CES-D and MMS scores, but after adjusting for age, living arrangements, and especially functional limitations, the relationship remained strong only for women.
The Set test, a simple rapid test of mental function, was applied to a sample of 189 elderly subjects. A score of under 15 on the test corresponded closely to a clinical diagnosis of dementia. Scores in the range 15 to 24 showed a lesser degree of association with dementia; while no subject with a score of 25 or over was demented. Low scores in the test were associated with physical illness, and to a limited extent with low social class, but not with affective illness. The test appears worthy of further studies in screening programs, and may have other clinical and epidemiological uses.
Little is known about whether persons with mentally demanding jobs are protected against cognitive impairment and whether this association is independent of intellectual abilities and other confounders. Longitudinal data from the Maastricht Aging Study (MAAS) were used to examine this association. After the 1993-1995 baseline examination, there was a first 3-year follow-up examination (1996-1998) among 630 men and women, aged 50 to 80, who exhibited no cognitive impairment at baseline. Persons with mentally demanding jobs had lower risks of developing cognitive impairment during follow-up (36 cases), compared with persons without such jobs (odds ratio = 0.79; 95% confidence interval: 0.65-0.96). About 1.5% of the persons with high mental work demands developed impairment compared to 4% of the persons with few work demands. The protective effect was independent of intellectual abilities and other confounders. Our findings provide evidence that continued and potentially modifiable mental stimulation during adult life may protect men and women against cognitive impairment.
Clinical and pathological data from the Rush Memory and Aging Project were used to test the hypothesis that distress proneness is associated with increased risk of Alzheimer's disease (AD). More than 600 older persons without dementia completed a 6-item measure of neuroticism, a stable indicator of proneness to psychological distress. At annual intervals thereafter, they underwent uniform evaluations that included clinical classification of AD and administration of 18 cognitive tests. Those who died underwent brain autopsy from which composite measures of AD pathology were derived. During a mean of about 3 years of follow-up, 55 people were clinically diagnosed with AD. In analyses that controlled for age, sex, and education, persons with a high level of distress proneness (score = 24, 90th percentile) were 2.7 times more likely to develop AD than those not prone to distress (score = 6, 10th percentile). Adjustment for depressive symptomatology or frequency of cognitive, social, and physical activity did not substantially change this effect. Distress proneness was also associated with more rapid cognitive decline. Among 45 participants who died and underwent brain autopsy, distress proneness was unrelated to diverse measures of AD pathology and was inversely related to cognition after controlling for AD pathology. The results support the hypothesis that distress proneness is associated with increased risk of dementia and suggest that neurobiologic mechanisms other than AD pathology may underlie the association.
To examine the effect of occupational characteristics on cognitive status change in members of the NAS-NRC Twins Registry of World War II veterans.
Participants completed the modified Telephone Interview for Cognitive Status (TICS-m) on three occasions spanning a period of approximately 7 years. Based on factor analysis, occupational characteristics were interpreted as reflecting general intellectual demands (GI), human interaction and communication (HC), physical exertion (PE), and visual attention (VA).
Based on regression analysis of TICS-m change that was dependent on twin pairing and additionally covarying for education, age at each testing event, medical conditions, and initial TICS-m score, higher GI was associated with a modest longitudinal improvement in TICS-m performance, whereas higher PE and VA were both associated with a modest decline. Subsequent analysis revealed that these significant effects were present among dizygotic twins, but not among monozygotic twins.
Previous findings of a relationship between occupational characteristics and cognitive performance in later life may be partially explained by genetic factors; however, until these genes are identified, occupational characteristics may be useful markers.
Cognition is not directly measurable. It is assessed using psychometric tests, which can be viewed as quantitative measures of cognition with error. The aim of this article is to propose a model to describe the evolution in continuous time of unobserved cognition in the elderly and assess the impact of covariates directly on it. The latent cognitive process is defined using a linear mixed model including a Brownian motion and time-dependent covariates. The observed psychometric tests are considered as the results of parameterized nonlinear transformations of the latent cognitive process at discrete occasions. Estimation of the parameters contained both in the transformations and in the linear mixed model is achieved by maximizing the observed likelihood and graphical methods are performed to assess the goodness of fit of the model. The method is applied to data from PAQUID, a French prospective cohort study of ageing.
To examine the association of job characteristics and intelligence to cognitive status in members of the National Academy of Sciences-National Research Council Twins Registry of World War II veterans.
Participants (n = 1,036) included individuals with an assessment of intelligence based on Armed Services testing in early adulthood. In late adulthood, these individuals completed the modified Telephone Interview for Cognitive Status (TICS-m) and occupational history as part of an epidemiologic study of aging and dementia. Occupational history was coded to produce a matrix of job characteristics. Based on factor analysis, job characteristics were interpreted as reflecting general intellectual demands (GI), human interaction and communication (HC), physical activity (PA), and visual attention (VA).
Based on regression analysis of TICS-m score covarying for age, intelligence, and years of education, higher levels of GI and HC were independently associated with higher TICS-m performance, whereas higher PA was independently associated with lower performance. There was an interaction of GI and intelligence, indicating that individuals at the lower range of intellectual aptitude in early adulthood derived greater cognitive benefit from intellectually demanding work.
Intellectually demanding work was associated with greater benefit to cognitive performance in later life independent of related factors like education and intelligence. The fact that individuals with lower intellectual aptitude demonstrated a stronger positive association between work and higher cognitive performance during retirement suggests that behavior may enhance intellectual reserve, perhaps even years after peak intellectual activity.
Manuel Pour l'Application du Test de Rétention Visuelle
Benton A. Manuel Pour l'Application du Test de Rétention
Visuelle. Applications Cliniques et Expérimentales, 2nd edition. Paris: Centre de Psychologie Appliquée, 1965.