Education and age-related decline in cognitive performance: Systematic review and meta-analysis of longitudinal cohort studies

Causal relationship and mediating role between depression and cognitive performance

BACKGROUND

Recent studies have increasingly emphasized the robust correlation between depression and cognitive function. However, it remains unclear whether this relationship is causal or merely coincidental. To address this uncertainty, we conducted two-sample bidirectional Mendelian randomization (MR) analyses to investigate the connection between depression and cognitive performance.

METHODS

We sourced genome-wide association study (GWAS) data for depression (NSNPs=21,306,230) from the FinnGen (R10) and for cognitive performance (NSNPs=10,049,954) from the IEU GWAS database. Causal effects employed methodologies such as Inverse variance weighted (IVW), weighted median, MR Egger, simple mode and weighted mode. Two-step analysis determined the contribution of the mediator variable to the outcomes. To determine stability and reliability, sensitivity analyses were performed that included an assessment of heterogeneity, horizontal pleiotropy, and the leave-one-out techniques.

RESULTS

This MR analysis identified 8 independent significant SNPs associated with depression and 81 SNPs linked to cognitive performance. Our findings revealed that depression increases the risk of developing deteriorating cognitive performance (IVW β, -0.11; 95 % confidence interval (CI), -0.18 - -0.05; PIVW value= 5.97E-04). Conversely, cognitive performance decline could also predispose individuals to depression [odds ratio (OR)IVW, 0.85; 95 % CI, 0.76 - 0.95; PIVW value=0.004]. Multivariate MR analysis confirmed the robustness of this bidirectional association. A two-step MR mediation analysis indicated that the pathway from depression to cognitive performance is mediated by pain, with a mediation effect size of -0.022 and a mediation ratio of 28.95 %. The pathway from cognitive performance to depression is mediated by frailty, with a mediation effect value of -0.028, representing 22.40 % of the mediation proportion.

CONCLUSION

A two-way causal relationship between depression and cognitive performance, with pain and frailty being mediating factors, respectively. Future research should prioritize mechanistic studies, targeted interventions, and personalized approaches to disentangle and mitigate the bidirectional effects of depression and cognitive performance.

Causal Effects of Schooling on Memory at Older Ages in Six Low- and Middle-Income Countries: Nonparametric Evidence With Harmonized Datasets

OBJECTIVES

Higher schooling attainment is associated with better cognitive function at older ages, but it remains unclear whether the relationship is causal. We estimated causal effects of schooling on performances on the Consortium to Establish a Registry for Alzheimer's Disease (CERAD) word-recall (memory) test at older ages in China, Ghana, India, Mexico, Russia, and South Africa.

METHODS

We used harmonized data (n = 30,896) on older adults (≥50 years) from the World Health Organization Study on Global Ageing and Adult Health. We applied an established nonparametric partial identification approach that bounds causal effects of increasing schooling attainment at different parts of the schooling distributions under relatively weak assumptions.

RESULTS

An additional year of schooling increased word-recall scores by between 0.01 and 0.13 SDs in China, 0.01 and 0.06 SDs in Ghana, 0.02 and 0.09 SDs in India, 0.02 and 0.12 SDs in Mexico, and 0 and 0.07 SDs in South Africa when increasing schooling from never attended to primary. No results were obtained for Russia at this margin due to the low proportion of older adults with primary schooling or lower. At higher parts of the schooling distributions (e.g., high school or university completion), the bounds cannot statistically reject null effects.

DISCUSSION

Our results indicate that increasing schooling from never attended to primary had long-lasting effects on memory decades later in life for older adults in 5 diverse low- and middle-income countries.

Multivariate decomposition of gender differentials in cognitive impairment among older adults in India based on Longitudinal Ageing Study in India, 2017-2018

BACKGROUND

Increasing life expectancy and declining fertility rates have increased the ageing population around the world. The literature lacks a consensus regarding the risk of cognitive impairments by gender.

OBJECTIVE

Our study aims to examine the differences in cognition impairments between male and female older adults in India.

METHODOLOGY

We utilized data from the first wave of the Longitudinal Ageing Study in India (LASI) (2017-18), analyzing 31,464 older adults aged 60 years and above (15,098 males and 16,366 females). Cognitive impairment is measured using the Harmonized Cognitive Assessment Protocol (HCAP) which includes five broad domains (memory, orientation, arithmetic function, executive function, and object naming). A multivariate decomposition analysis was performed using STATA 17 software to identify covariates'contributions, which explain the group differences to average predictions.

FINDINGS

The prevalence of cognitive impairment was significantly higher among females (19.8%) than males (6.4%) (p < 0.001). Gender disparities were more pronounced among the oldest-old (41.5% vs. 15.9%), widowed individuals (24.6% vs. 9.8%), those with no education (25.1% vs. 11.8%), and individuals living alone (23.4% vs. 5.0%). Decomposition analysis revealed that 62% of the gender gap in cognitive impairment was attributable to differences in compositional factors, primarily education (42%), marital status (6%), working status (6%), difficulty in instrumental activities of daily living (3%), and physical activity (2%). The remaining 38% of the disparity was due to differences in how these factors impacted men and women.

CONCLUSION

The findings indicate that cognitive impairments are more pronounced among women. Gender-responsive interventions improving education access among the female gender would bring relevant and desired results.

Knowledge, attitudes, and practices regarding intrinsic capacity in the elderly population: A cross-sectional study in Shanghai, China

To investigate the knowledge, attitudes, and practices (KAP) of the elderly population regarding their intrinsic capacity, as defined by the World Health Organization as a marker of healthy aging. A cross-sectional study was conducted at the Shanghai Traditional Chinese Medicine Hospital from July to November 2023. Participants' socio-demographic information and KAP scores were collected through a self-designed questionnaire. A total of 507 elderly individuals participated, with 53.25% being male and a mean age of 70.76 ± 7.63 years. The mean knowledge, attitude, and practice scores were 19.58 ± 8.85, 30.07 ± 4.81, and 34.71 ± 7.77, respectively. Pearson's correlation analysis showed significant positive correlations among the KAP scores (all P < 0.001). Multivariate logistic regression indicated that knowledge scores (OR = 1.127, P < 0.001), attitude scores (OR = 1.189, P < 0.001), and current employment status (OR = 2.759, P = 0.009) were associated with proactive practices. Structural equation modeling demonstrated that knowledge had a direct influence on attitude (β = 0.572, P < 0.001) and practice (β = 0.776, P < 0.001), while attitude directly impacted practice (β = 0.412, P < 0.001). The study reveals that the elderly lack knowledge but have positive attitudes and proactive behaviors about intrinsic capacity. Enhancing education and attitudes is vital for healthy aging and well-being.

Positive Childhood Experiences, Cognition, and Biomarkers of Alzheimer's Disease

Positive childhood experiences (PCEs) have unknown effects on late life cognition and Alzheimer's Disease biomarkers. We examined 406 Asian, 1179 Black, 349 Latinx, and 498 White KHANDLE and STAR study participants with data on PCEs, longitudinal cognitive measures, MRI (n = 560), and amyloid PET (n = 281). We conducted mediation and multigroup models within the structural equation modeling framework allowing us to examine the direct association of PCEs with episodic memory level and change as well as the indirect effects of PCEs through education. We additionally conducted linear regressions examining the association of PCEs with MRI and amyloid PET outcomes. Average participant age was 74 (53-90) and 62% were female. Overall, PCEs were positively associated with memory intercept and change. Education significantly mediated the association between PCEs and memory intercept. PCEs were not associated with hippocampal volume or amyloid burden in the combined sample or across individual ethnocultural groups. PCEs are positively related to episodic memory through the promotion of educational attainment.

New regression-based norms for the Trail Making Test on Norwegian older adults: Understanding the effect of education

Objective: To produce regression-based norms for older adults on the revised Trail Making Test with alphabet support (TMT-NR3). By examining the potential modulating effects and putative interaction effects of age, education, and sex, we aim to gain insights into cognitive aging and the effects of education. Method: Altogether, 440 healthy participants with an age-span from 70 to 92 years from the NorFAST (n = 249) and the HUNT (n = 191) studies were included. Regression-based norms for TMT-A, TMT-B, and derived measures TMT B-A, TMT B/A, and TMT-β were produced. Models were assessed for pertinent linear, curvilinear, or interaction effects of age, education, and sex. We evaluated and compared our norms to published North American TMT norms. Results: Higher age was linearly associated with lower performance on all measures. No sex differences were found. We found a reduced positive association with education on test performance at higher age. However, this interaction effect was found to be driven by participants with low education. Our validated proposed norms showed a better fit to observed data than the existing norms. Conclusion: The norms were adjusted for age on all measures. Norms without age adjustment are made available for TMT B/A due to a slightly better fit of this model. The results indicate (i) that only processing speed and not set-shifting declines with age and (ii) that the selection process for education might be more important than actual education for older-age performance.

Reserves and their role in protecting against anxiety and depressive symptoms among undocumented migrants undergoing regularization

Resources help individual to function in everyday life, while reserves, a specific type of resources, help them to overcome shock and stress. Evidence is scarce about whether reserves (be they cognitive, economic or relational) protect people's mental health in situations of temporary stress. Based on a cohort study following undocumented migrants undergoing a stressful life course transition (regularisation with local authorities), we identified which resources and reserves, and which types, better protect mental health. To examine whether reserves, and which types, are prospectively associated with anxiety and depressive symptoms, whether this association is independent of resources, and whether reserves modify the effect of regularisation on anxiety and depressive symptoms. A two-wave cohort study followed 456 undocumented migrants (mean age 44 years) from 2017 to 2020, half (48%) of whom were involved in a pilot regularisation policy implemented by the local authorities of Geneva, Switzerland. Anxiety was measured with the Generalised Anxiety Disorder Questionnaire-7 and depressive symptoms with the Patient Health Questionnaire-9. Economic, cognitive and relational reserves were measured at baseline, as well as economic and relational resources. Generalised Estimating Equations tested the associations of reserves and resources with anxiety and depressive symptoms, and the interaction between reserves/resources and regularisation status. Economic and relational reserves were associated with lower anxiety and depressive symptoms, independent of economic and relational resources. Cognitive reserves were not associated with lower anxiety and depressive symptoms. Regularised participants reported lower anxiety and depressive symptoms compared to non-regularised undocumented participants. Reserves did not modify the effect of regularisation on anxiety and depressive symptoms. The provision of reserves for undocumented migrants may protect mental health but may not alter the impact of regularisation on mental health. Further research is needed among vulnerable groups experiencing psychologically distressing events to test the reserve hypothesis.

Reevaluating the Role of Education in Cognitive Decline and Brain Aging: Insights from Large-Scale Longitudinal Cohorts across 33 Countries

Why education is linked to higher cognitive function in aging is fiercely debated. Leading theories propose that education reduces brain decline in aging, enhances tolerance to brain pathology, or that it does not affect cognitive decline but rather reflects higher early-life cognitive function. To test these theories, we analyzed 407.356 episodic memory scores from 170.795 participants > 50 years, alongside 15.157 brain MRIs from 6.472 participants across 33 Western countries. More education was associated with better memory, larger intracranial volume and slightly larger volume of memory-sensitive brain regions. However, education did not protect against age-related decline or weakened effects of brain decline on cognition. The most parsimonious explanation for the results is that the associations reflect factors present early in life, including propensity of individuals with certain traits to pursue more education. While education has numerous benefits, the notion that it provides protection against cognitive or brain decline is not supported.

Does the coexistence of pain and depressive symptoms accelerate cognitive decline?

OBJECTIVES

Investigate whether the coexistence of pain and depressive symptoms is a risk factor for cognitive decline in individuals aged 50 or older.

METHOD

Longitudinal trajectory study involving 4,718 participants from the English Longitudinal Study of Ageing (ELSA). Joint pain was self-reported, and intensity was classified as mild, moderate/intense. Depressive symptoms were investigated using the Centre for Epidemiologic Studies Depression Scale (CES-D-8 ≥ 4). The sample was divided into six groups: no pain and no depression (NP/NDe), mild pain and no depression (MP/NDe), moderate/intense pain and no depression (M-IP/NDe), no pain and depression (NP/De), mild pain and depression (MP/De), and moderate/intense pain and depression (M-IP/De). The outcome of interest was performance in memory, executive function, and global cognition. Generalised linear mixed models were used to analyse performance in the cognitive domains and global cognition score as a function of pain and depressive symptoms during 12 years of follow-up.

RESULTS

Over time, individuals with M-IP/De had a greater memory decline (-0.038 SD/year, 95%CI: -0.068 to -0.007) and the global cognition score (-0.033 SD/year, 95%CI: -0.063 to -0.002) than those with NP/NDe.

CONCLUSION

The coexistence of moderate/intense pain and depressive symptoms is a risk factor for the decline of global cognition and memory.

Reevaluating the Role of Education in Cognitive Decline and Brain Aging: Insights from Large-Scale Longitudinal Cohorts across 33 Countries

Why education is linked to higher cognitive function in aging is fiercely debated. Leading theories propose that education reduces brain decline in aging, enhances tolerance to brain pathology, or that it does not affect cognitive decline but rather reflects higher early-life cognitive function. To test these theories, we analyzed 407.356 episodic memory scores from 170.795 participants >50 years, alongside 15.157 brain MRIs from 6.472 participants across 33 Western countries. More education was associated with better memory, larger intracranial volume and slightly larger volume of memory-sensitive brain regions. However, education did not protect against age-related decline or weakened effects of brain decline on cognition. The most parsimonious explanation for the results is that the associations reflect factors present early in life, including propensity of individuals with certain traits to pursue more education. While education has numerous benefits, the notion that it provides protection against cognitive or brain decline is not supported.

The Impact of Prior Incarceration on Cognitive Trajectories Among Older Adults: Evidence From the Health and Retirement Study

OBJECTIVES

This study examines the association between prior incarceration and cognition trajectories among older adults in the United States.

METHODS

Data are from the Health and Retirement Study (HRS), a nationally representative longitudinal survey of older adults in the United States. The analysis included respondents aged 55 and older who participated in the 2012-2020 HRS surveys and had valid responses on Langa-Weir cognition scores, incarceration history, and covariates (n = 5,663). Cognition trajectories were estimated using group-based trajectory modeling, and multinomial logistic regression was used to assess the relationship between prior incarceration and cognition trajectory group membership.

RESULTS

The study identified four distinct cognition trajectories. Formerly incarcerated individuals were significantly more likely to be in cognition trajectory groups defined by lower cognition scores and steeper declines in cognitive functioning over time. However, these associations were attenuated after accounting for sociodemographic and health-related characteristics, and all associations were rendered statistically nonsignificant after accounting for educational attainment.

DISCUSSION

These findings highlight poorer cognition among older formerly incarcerated individuals compared with their never incarcerated counterparts, as well as underscore the role of educational attainment in this relationship. Future research and data collection efforts are needed to further understand the nexus between incarceration and cognitive functioning and the mechanisms underpinning this association.

Predilection for Perplexion: Preoperative microstructural damage is linked to postoperative delirium

Postoperative delirium is the most common postsurgical complication in older adults and is associated with an increased risk of long-term cognitive decline and Alzheimer's disease (AD) and related dementias (ADRD). However, the neurological basis of this increased risk-whether postoperative delirium unmasks latent preoperative pathology or leads to AD-relevant pathology after perioperative brain injury-remains unclear. Recent advancements in neuroimaging techniques now enable the detection of subtle brain features or damage that may underlie clinical symptoms. Among these, Neurite Orientation Dispersion and Density Imaging (NODDI) can help identify microstructural brain damage, even in the absence of visible macro-anatomical abnormalities. To investigate potential brain microstructural abnormalities associated with postoperative delirium and cognitive function, we analyzed pre- and post-operative diffusion MRI data from 111 patients aged ≥60 years who underwent non-cardiac/non-intracranial surgery. Specifically, we investigated preoperative variation in diffusion metrics within the posterior cingulate cortex (PCC), a region in which prior work has identified glucose metabolism alterations in the delirious brain, and a key region in the early accumulation of amyloid beta (Aβ) in preclinical AD. We also examined the relationship of preoperative PCC NODDI abnormalities with preoperative cognitive function. Compared to patients who did not develop postoperative delirium (n=99), we found increased free water (FISO) and neurite density index (NDI) and decreased orientation dispersion index (ODI) in the dorsal PCC before surgery among those who later developed postoperative delirium (n=12). These FISO differences before surgery remained present at six weeks postoperatively, while these NDI and ODI differences did not. Preoperative dorsal PCC NDI and ODI values were also positively associated with preoperative attention/concentration performance, independent of age, education level, and global brain atrophy. Yet, these diffusion metrics were not correlated with cerebrospinal fluid Aβ positivity or levels. These results suggest that preoperative latent brain abnormalities within the dorsal PCC may underlie susceptibility to postoperative delirium, independent of AD-related (i.e., Aβ) neuropathology. Furthermore, these preoperative microstructural differences in the dorsal PCC were linked to preoperative deficits in attention/concentration, a core feature of postoperative delirium. Our findings highlight microstructural vulnerability within the PCC, a key region of the default mode network, as a neuroanatomic locus that can help explain the link between preoperative attention/concentration deficits and increased postoperative delirium risk among vulnerable older surgical patients.

State Schooling Policies and Cognitive Performance Trajectories: A Natural Experiment in a National US Cohort of Black and White Adults

BACKGROUND

Education is strongly associated with cognitive outcomes at older ages, yet the extent to which these associations reflect causal effects remains uncertain due to potential confounding.

METHODS

Leveraging changes in historical measures of state-level education policies as natural experiments, we estimated the effects of educational attainment on cognitive performance over 10 years in 20,248 non-Hispanic Black and non-Hispanic White participants, aged 45+ in the Reasons for Geographic and Racial Disparities in Stroke cohort (2003-2020) by (1) using state- and year-specific compulsory schooling laws, school-term length, attendance rate, and student-teacher ratio policies to predict educational attainment for US Census microsample data from 1980 and 1990, and (2) applying policy-predicted years of education (PPYEd) to predict memory, verbal fluency, and a cognitive composite. We estimated overall and race- and sex-specific effects of PPYEd on level and change in each cognitive outcome using random intercept and slope models, adjusting for age, year of first cognitive assessment, and indicators for state of residence at age 6.

RESULTS

Each year of PPYEd was associated with higher baseline cognition (0.11 standard deviation [SD] increase in composite measure for each year of PPYEd, 95% confidence interval [CI] = 0.07, 0.15). Subanalyses focusing on individual cognitive domains estimate the largest effects of PPYEd on memory. PPYEd was not associated with the rate of change in cognitive scores. Estimates were similar across Black and White participants and across sex.

CONCLUSIONS

Historical policies shaping educational attainment are associated with better later-life memory, a major determinant of dementia risk.

Characterizing cancer-related cognitive impairments and impact on quality of life in women with metastatic breast cancer

PURPOSE

Little is known about cancer-related cognitive impairments (CRCI) in women with metastatic breast cancer (MBC). The purpose of this study is to (1) comprehensively describe CRCI and any associated psychosocial and behavioral symptoms, (2) determine observable sociodemographic and clinical risk factors for CRCI, and (3) explore cognitive and psychosocial predictors of quality of life and social functioning in women living with MBC.

METHODS

Using a cross-sectional design, women with MBC completed assessments (objective and subjective measures of CRCI including 3 open-ended questions, measures of psychosocial and behavioral factors, and assessments of quality of life and social function), and data were analyzed using descriptive statistics, qualitative content analysis, correlation analyses, t tests, analysis of variance, and linear regression models.

RESULTS

Data from 52 women were analyzed. 69.2% of the sample reported clinically significant CRCI and 46% of the sample scored < 1 standard deviation below the standardized mean on one or more cognitive tests. Those with triple-negative MBC (compared to HER2+), recurrent MBC (compared to de novo), and no history of chemotherapy had worse subjective CRCI, and those without history of surgery and older age had worse objective CRCI. Subjective CRCI, but not objective CRCI, was significantly associated with quality of life and social functioning.

CONCLUSION

Subjective and objective CRCI are likely a common problem for those with MBC. Subjective CRCI is associated with poorer quality of life and lower social functioning. Healthcare providers should acknowledge cognitive symptoms, continually assess cognitive function, and address associated unmet needs across the MBC trajectory.

Demographic predictors of cognitive performance in participants of a local substance abuse recovery program

Background

Cognitive impairments have been reported among disadvantaged populations.

Objective

We aimed to ascertain how demographic factors are associated with cognitive performance in individuals enrolled in a local substance abuse recovery program.

Methods

In total, 106 participants were included in the study. Besides demographic information, vital signs and cognitive function, measured by Mini-Mental State Examination (MMSE) or Montreal Cognitive Assessment (MoCA), were collected from each participant. Welch's t-test and regression analysis were used to analyze how different demographic factors are associated with cognitive assessment scores.

Results

The mean age of African American (AA) participants (n = 43) were 48.35 ± 1.65 years, which are older than that for the White participants of 38.95 ± 1.36 (n = 63) years. Compared to the AA participants, the White participants had a larger variance in attained education levels. The average MMSE scores were 27.09 ± 0.40 for AA participants, which is lower than that for the White participants of 28.52 ± 0.33 (p < 0.05). The average MoCA scores were 23.71 ± 0.54 for AAs, which is lower that for the White participants of 26.65 ± 0.44 (p < 0.001). The AA and White participant groups had cognitive impairment rate of 18.6% and 6.35%, respectively. The regression analysis indicates age and education are two significant predictors for the cognitive performance difference between the two racial groups.

Conclusions

Significant disparities in cognitive performance exist between two racial groups of enrolled in a local substance abuse recovery program. The older age and lower levels of attained education in AA participants can explain the poorer cognitive function than the White participants.

Machine learning algorithms to predict mild cognitive impairment in older adults in China: A cross-sectional study

OBJECTIVE

This study aimed to explore the predictive value of machine learning (ML) in mild cognitive impairment (MCI) among older adults in China and to identify important factors causing MCI.

METHODS

In this study, 6434 older adults were selected based on the data of the China Health and Elderly Care Longitudinal Survey (CHARLS) in 2020, and the dataset was subsequently divided into the training set and the test set, with a ratio of 6:4. To construct a prediction model for MCI in older adults, six ML algorithms were used, including logistic regression, KNN, SVM, decision tree (DT), LightGBM, and random forest (RF). The Delong test was used to compare the differences of ROC curves of different models, while decision curve analysis (DCA) was used to evaluate the model performance. The important contributions of the prediction results were then used to explain the model by the SHAP value.The Matthews correlation coefficient (MCC) was calculated to evaluate the performance of the models on imbalanced datasets. Additionally, causal analysis and counterfactual analysis were conducted to understand the feature importance and variable effects.

RESULTS

The area under the ROC curve of each model range from 0.71 to 0.77, indicating significant difference (P < 0.01). The DCA results show that the net benefits of LightGBM is the largest within various probability thresholds. Among all the models, the LightGBM model demonstrated the highest performance and stability. The five most important characteristics for predicting MCI were educational level, social events, gender, relationship with children, and age. Causal analysis revealed that these variables had a significant impact on MCI, with an average treatment effect of -0.144. Counterfactual analysis further validated these findings by simulating different scenarios, such as improving educational level, increasing age, and increasing social events.

CONCLUSION

The ML algorithm can effectively predict the MCI of older adults in China and identify the important factors causing MCI.

The role of individual and environmental socio-economic resources for cognitive change in very old age

OBJECTIVES

Very old adults aged 80+ years old belong to the fastest growing population segment in many countries. Nevertheless, this age group is often underrepresented in studies of cognitive aging. The goal of this study was to examine individual and environmental socio-economic resources as correlates of cognitive aging in very old age.

METHOD

We used two waves of data from 2017-2018 and 2019-2021 as part of NRW80+, a survey of a population-based sample of very old individuals who are registered with their main residence in North-Rhine Westphalia, the most populous federal state in Germany. The analyses are based on data from 797 participants, who provided data on at least one cognitive test at both waves. Individual socio-economic resources included education, income, wealth, and occupational prestige. Environmental factors were assessed at the municipality level, including population density, unemployment, (public) transportation, broadband availability, healthcare, and libraries. Control variables included age, sex, marital/partner status, living alone, and living in a nursing care institution. Data were analyzed with latent difference score models.

RESULTS

Education and wealth were independently associated with better cognitive function at baseline. None of the individual socio-economic variables was significantly related to change in cognitive function. Beyond these individual characteristics and control variables, higher population density and higher broadband availability, but also higher unemployment rate were associated with better baseline cognitive function. Greater distance to highways, but also fewer hospital beds and a higher number of residents per medical doctor were associated with less decline.

DISCUSSION

Our findings suggest that individual socio-economic resources continue to be associated with better cognitive function in very old age, but are unrelated to short-term cognitive decline. In addition, there is some evidence for associations of baseline cognitive function and cognitive change with environmental factors over and above individual resources. Implications for future research are discussed.

Correlates of neurocognitive performance in older adults with chronic pain and negative emotions: baseline data from the problem adaptation therapy for pain (PATH-pain) randomized controlled trial

Chronic pain is highly prevalent among older adults, is associated with cognitive deficits, and is commonly treated in primary care. We sought to document the extent of impairment across specific neurocognitive domains and its correlates among older adults with chronic pain in primary care. We analyzed baseline data from the Problem Adaptation Therapy for Pain trial, which examined a psychosocial intervention to improve emotion regulation in 100 adults ≥ 60 years with comorbid chronic pain and negative emotions, who did not have evidence of moderate-to-severe cognitive impairment. Questionnaires on comorbidities, depressive symptoms, pain intensity, and pain-related disability were administered along with the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS) and the Montreal Cognitive Assessment (MoCA). Multiple regression assessed the relationship between demographic and clinical characteristics with specific neurocognitive domains. Over half of participants (56%) had mild-to-moderate cognitive impairment (<26 on the MoCA). Across domains, participants scored the lowest in visuospatial/constructional (M = 86.2; SD = 15.7), and 15%-23% scored at least one standard deviation below the mean for immediate and delayed memory, visuospatial/constructional, and attention. In adjusted models, greater medical comorbidities were associated with poorer performance on the total RBANS, immediate memory, and attention. Cognitive deficits in older adults with chronic pain in primary care are substantial, with varying levels of deficits by neurocognitive domain. Future research should examine synergistic effects of chronic pain and comorbidities on cognition, and the impact of cognitive deficits on older adults' ability to engage in pain interventions and self-management behaviors.

Cross-sectional and longitudinal associations between late-life depressive symptoms and cognitive deficits: 20-year follow-up of the Kuakini Honolulu-Asia aging study

OBJECTIVE

To examine depressed affect, somatic complaints, and positive affect as longitudinal predictors of fluid, crystallized and global cognitive performance in the Kuakini Honolulu-Asia Aging Study (HAAS), a large prospective cohort study of Japanese-American men.

METHODS

We assessed 3,088 dementia-free Kuakini-HAAS participants aged 71-93 (77.1 ± 4.2) years at baseline (1991-1993). Depressive symptoms were evaluated by the Center for Epidemiologic Studies Depression (CES-D) Scale. Baseline CES-D depression subscales (depressed and positive affects; somatic complaints) were computed. The Cognitive Abilities Screening Instrument (CASI) measured cognitive performance on a 100-point scale; fluid and crystallized cognitive abilities were derived from CASI factor analysis. Cognition was also evaluated at 4 follow-up examinations over a 20-year period. Multiple regression assessed baseline CES-D subscales as predictors of cognitive change. The baseline covariates analyzed were CASI, age, education, prevalent stroke, APOE ε4 presence, and the longevity-associated FOXO3 genotype.

RESULTS

Cross-sectionally, baseline CES-D subscales were related to cognitive measures; e.g., higher depressed affect was associated with lower crystallized ability (β = -0.058, p ≤ 0.01), and somatic complaints were linked to poorer fluid ability (β = -0.045, p ≤ 0.05) and to worse global cognitive function as measured by total CASI score (β = -0.038, p ≤ 0.05). However, depression subscales did not significantly or consistently predict fluid ability, crystallized ability, or global cognitive performance over time.

CONCLUSION

Psychological and physical well-being were associated with contemporaneous but not subsequent cognitive functioning. Assessment of depressive symptoms may identify individuals who are likely to benefit from interventions to improve mood and somatic health and thereby maintain or enhance cognition.

Neurocognitive disparities: investigating ethnicity and mental health in rural aging adults

OBJECTIVES

We explored whether depression and anxiety moderated the association of ethnicity and neurocognitive functioning among a sample of Hispanic and non-Hispanic White rural aging adults.

METHOD

1,462 rural dwelling adults (Mage = 59.4 years, SDage = 12.12) were included in the analysis for this study.

RESULTS

MANCOVAs revealed a significant (ps < .001) multivariate effect of ethnicity on all five indices of neurocognitive functioning when controlling for anxiety and sociodemographic variables (V = .20, F(5,1,310) = 64.69) and depression and sociodemographic variables in the second model (V = .20, F(5,1310) = 65.80, p < .001). There was also a multivariate effect of anxiety (V = .02, F(5,1310) = 4.57, p < .001) and depression (V = .04, F(5, 1310) = 11.38, p < .001) on neurocognitive functioning when controlling for sociodemographic variables and ethnicity.

CONCLUSION

Findings revealed that Hispanic rural aging adults scored lower on neurocognitive functioning compared to non-Hispanic White rural aging adults, irrespective of depression or anxiety. Depression and anxiety contributed to lower scores on neurocognitive functioning-yet this finding was not as robust. Culturally tailored interventions targeting risk factors for neurocognitive impairment in Hispanic rural aging adults are imperative to mitigate neurocognitive disparities. One possible reason for differences in neurocognitive functioning between Hispanic individuals and non-Hispanic individuals is stress as ethnic health disparities have been found to be shaped by a diverse range of lifetime stressors that are disproportionally exacerbated for ethnic minorities.

Norms for neuropsychological tests in cognitively healthy French oldest old adults

OBJECTIVE

Normal aging often leads to cognitive decline, and oldest old people, over 80 years old, have a 15% risk of developing neurodegenerative diseases. Therefore, it is important to have appropriate tools to assess cognitive function in old age. The study aimed to provide new norms for neuropsychological tests used to evaluate the cognitive abilities in people aged 80 years and older in France, focusing on the impact of education and gender differences.

METHOD

107 healthy participants with an average age of 85.2 years, with no neurological history or major cognitive deficits were included. A comprehensive neuropsychological assessment was performed, covering several cognitive functions such as memory, visuospatial abilities, executive functions, attention, processing speed, and praxis.

RESULTS

Individuals with lower levels of education performed poorly on some tests and took longer to complete. Gender differences were observed, with women outperforming men in verbal episodic memory, while men showed better performance in visuoconstructive tasks. The participants showed lower performance in verbal episodic memory compared to norms established in previous French studies. In relation to executive functions, participants were slower to perform complex tasks than participants in previous studies.

CONCLUSION

This study provides cognitive norms specifically adapted to the oldest old population, which differ from established norms for younger aging adults. It highlights the importance of including these norms in future clinical and scientific investigations. The findings underscore the importance of education on cognitive abilities and emphasize the need to consider gender differences when assessing cognitive functions in aging populations.

Gender differences in the association between education and late-life cognitive function in the LifeAfter90 Study: A multiethnic cohort of the oldest-old

INTRODUCTION

Few studies have examined the relationship between education and cognition among the oldest-old.

METHODS

Cognitive assessments were conducted biannually for 803 participants (62.6% women) of LifeAfter90, a longitudinal study of individuals ≥ 90 years old. Gender differences in associations between education (< high school, high school, some college, and ≥ college) and cognition (verbal episodic memory, semantic memory, and executive function) were examined at baseline and longitudinally using linear mixed models.

RESULTS

Higher education levels were associated with better cognitive performance at baseline for both men and women. College completion was more strongly associated with better baseline executive function among women. Education-cognition associations for baseline verbal episodic memory and baseline semantic memory did not differ by gender. Education was not associated with a decline in any domain-specific cognitive scores, regardless of gender.

DISCUSSION

Education is associated with cognitive function among the oldest-old and varies by gender and cognitive domain at baseline but not over time.

HIGHLIGHTS

In the oldest-old, higher education was associated with better cognitive function. College completion was more strongly associated with executive function in women. Education was not associated with cognitive decline after age 90 regardless of gender. Improving education could decrease gaps in cognitive level among older individuals.

Factors associated with low health literacy in unpaid caregivers of older people: a systematic review

Health literacy is a public health issue. Unpaid caregivers of older people with low health literacy may have difficulties providing care, exerting a negative impact on the care process. The aim of the present study was to perform a systematic review of the literature on factors associated with low health literacy in unpaid caregivers of older people. Searches for relevant articles were conducted in the Cochrane Library, Embase, LILACS, PubMed and Web of Science databases. A total of 1440 articles were identified, nine of which met the eligibility criteria and were included in the systematic review, which was registered in PROSPERO (CRD42024522986). A total of 2209 unpaid caregivers participated in the studies selected for this review. Most were women (67.2%). The average frequency of inadequate health literacy was 27.1%. Sociodemographic characteristics (i.e. advanced age, low educational level, the female sex), factors related to the care process (i.e. low acculturation, low empowerment, poor ability to read medication package inserts, lower care capacity, greater disease severity, hospitalization of care recipients), cognitive factors and factors related to quality of life/well-being (i.e. less social support, poorer quality of life, greater cognitive impairment, higher levels of burden) were associated with low health literacy. In conclusion, low health literacy in unpaid caregivers of older people is associated with sociodemographic, care-related and cognitive factors as well as factors related to quality of life/well-being. Low health literacy may exert a negative impact on the health of caregivers and, consequently, the quality of care provided to older people.

The Mediating Effects of Education and Occupational Complexity Between Race and Longitudinal Change in Late Life Cognition in ACTIVE

This study examined educational and occupational inequality as two aspects of social determinants of health that might mediate the longitudinal relationship between racialization and late life cognitive level and change. Participants were 2371 individuals racialized as Black and White from the ACTIVE study who provided occupational data. Data were analyzed from baseline and five assessments over 10-years using structural equation modeling. Black/White race served as the predictor, occupational complexity (OC) and years of education as mediators, and cognitive (memory, reasoning, and speed of processing) intercept, linear slope, and quadratic slope as the dependent variables. Black/White race showed significant indirect associations through education and OC on level of performance in cognition, linear change in reasoning and memory, and quadratic change in reasoning. Education and OC accounted for 11-16% of the association between race and cognitive level and represent modifiable social determinants of health that are associated with disparities in cognitive aging.

Causal relationship between educational attainment and chronic pain: A Mendelian randomization study

Educational attainment (EA) is often used as a symbol of socioeconomic status and is associated with several diseases. However, uncertainty remains regarding the potential relationship between EA and chronic pain. This study aimed to evaluate the potential causal association between EA and chronic pain. The primary method employed in Mendelian randomization (MR) analysis was inverse-variance weighted method. Additionally, MR-Egger intercept, Cochran Q, and MR-PRESSO statistical analyses were conducted to assess potential pleiotropy and heterogeneity. The MR analysis provided evidence that genetically predicted additional education significantly reduced the risk of chronic pain. Specifically, this genetic factor may reduce multisite chronic pain by 27.6%, and chronic widespread pain by 3.8%. The results of sensitivity analysis indicated the reliability of our causal estimates. Higher levels of EA may provide protection against chronic pain risk. Enhancing education, narrowing social and economic disparities may help alleviate the burden of chronic pain.

Cognitive reserve proxies are associated with age-related cognitive decline - Not age-related gait speed decline

Cognition and gait share brain substrates in aging and dementia. Cognitive reserve (CR) allows individuals to cope with brain pathology and delay cognitive impairment and dementia. Yet, evidence for that CR is associated with age-related cognitive decline is mixed, and evidence for that CR is associated with age-related gait decline is limited. In 1,079 older (M Age = 75.4 years; 56.0% women) LonGenity study participants without dementia at baseline and up to 12 years of annual follow-up (M follow-up = 3.9 years, SD = 2.5 years), high CR inferred from cognitive (education years), physical (number of blocks walked per day; weekly physical activity days), and social (volunteering/working; living with someone) proxies were associated with slower rates of age-related decline in global cognition - not gait speed decline. Thus, cognitive, physical, and social CR proxies are associated with cognitive decline in older adults without dementia. The multifactorial etiology and earlier decline in gait than cognition may render it less modifiable by CR proxies later in life.

Adult Child Financial Disadvantage and the Cognitive Trajectories Among Older Parents in the United States

OBJECTIVES

Adult child socioeconomic status (SES) has been identified as a predictor of older parents' cognitive aging. However, studies have primarily relied on educational attainment as the sole measure of adult child SES. We evaluated the relationship between adult children's financial disadvantage and cognitive outcomes of older parents in the United States.

METHODS

We used data from U.S. Health and Retirement Study (2000-2014, n = 15,053 respondents ≥51 years with at least 1 adult child). Adult child financial disadvantage was measured with 3 indicators of extremely low income, unemployment, and lack of homeownership. We used linear mixed models to estimate the association between adult child financial disadvantage and the rate of decline in verbal memory scores, controlling for respondents' sociodemographic characteristics.

RESULTS

Having at least 1 adult child (vs no adult children) with extremely low income was found to be associated with lower verbal memory (b = -0.041, 95% confidence interval [CI]: -0.043, -0.039) at baseline. There was a small but significant association with the rate of decline in verbal memory z-scores (b = 0.004, 95% CI: 0.000, 0.008) and some evidence of heterogeneity by parent gender, marital status, and SES.

DISCUSSION

Offspring financial disadvantage may be influential for older parents' initial level of memory function, although evidence of associations with memory decline was weak. Public policy interventions aimed at improving the economic conditions of adult children may indirectly benefit the cognitive performance of disadvantaged parents in their later life.

Longitudinal associations of effort and reward at work with changes in cognitive function: evidence from a national study of U.S. workers

PURPOSE

This study aimed to examine longitudinal associations of workplace effort and reward with changes in cognitive function among United States workers.

METHODS

Data from the national, population-based Midlife in the United States (MIDUS) study with a 9-year follow-up were used. Validated workplace effort and reward scales were measured at baseline, and cognitive outcomes (including composite cognition, episodic memory, and executive functioning) were measured with the Brief Test of Adult Cognition by Telephone (BTACT) at baseline and follow-up. Multivariable linear regression analyses based on generalized estimating equations (GEE) examined the longitudinal associations under study.

RESULTS

Among this worker sample of 1,399, after accounting for demographics, socioeconomics, lifestyle behaviors, health conditions, and job control, high reward at baseline was associated with increased composite cognition (regression coefficient: 0.118 [95% CI: 0.049, 0.187]), episodic memory (0.106 [0.024, 0.188]), and executive functioning (0.123 [0.055, 0.191]) during follow-up. The joint exposure of 'high effort and high reward' was also associated with increased composite cognition (0.130 [0.030, 0.231]), episodic memory (0.131 [0.012, 0.250]), and executive functioning (0.117 [0.017, 0.216]), while the combination of 'low effort and high reward' was associated with increased composite cognition (0.106 [0.009, 0.204]) and executive functioning (0.139 [0.042, 0.235]).

CONCLUSION

Findings suggest that workplace high reward is related to improved cognitive scores among United States workers. Future research should investigate larger cohorts over longer timespans and expand into disease outcomes such as dementia. If these findings emerge as causal, relevant workplace rewards to promote worker cognitive health should be considered.

Mechanisms and Functions of the Cerebral-Cognitive Reserve in Patients with Alzheimer's Disease: A Narrative Review

BACKGROUND

The need for scientific knowledge about aging is predicated on the demand of modern society to extend the active life of a person. To maintain intellectual longevity, it is necessary to take into account not only the pathological, but also compensatory mechanisms that arise during aging. The cerebral-cognitive reserve (CCR) influences the rate of transition from pre-phenomenological stages to the clinical stage of the disease, thereby changing the prognosis of Alzheimer's disease (AD).

AIM

The aim of this work was to review meta-analyses from studies that have examined the principles and functions of the CCR in people with AD.

METHODS

The work included 83 scientific publications devoted to the issues of the CCR in neurodegenerative diseases such as AD. The Results and Discussion sections of this article provide reviews of the results of 12 meta-analyses published from 2012 to 2024 and selected from the PubMed and eLibrary databases using the following keywords in English and Russian: "cerebral reserve", "cognitive "reserve", and "Alzheimer's disease". The scope of the definition was not limited, since the goal here was to determine the terminological boundaries of the concepts of "cognitive reserve" and "single brain reserve".

RESULTS

The modern understanding of AD as a biological continuum covering the preclinical, prodromal, and clinical phases of the disease makes it possible to infer that insufficiency of protective factors underlies the progression of AD. The cognitive reserve is involved in the sanogenetic protective mechanism during neurodegeneration. The cognitive reserve is a theoretical concept that reflects modern research's understanding of how the integrative functioning of the brain (cerebral) and cognitive reserves extend the period of active intellectual longevity through energy-saving mechanisms. It considers these mechanisms as central to healthy mental activity and in slowing the progression of neurodegenerative diseases. At some point, an increase in excess interneuronal activity that reflects the hypercompensatory function of the reserve would accelerate the depletion of brain structures and contribute to clinical and psychopathological manifestations of AD.

CONCLUSION

The concept of the CCR puts the spotlight on the need to determine the compensatory indicators of cognitive deficit in AD, assess the architecture and volume of the reserve, and develop and follow protocols for its maintenance. It appears just as crucial to adopt measures to prevent the Reserve's depletion as early as at the preclinical stages of the disease. Elaborating protective and compensatory mechanisms that help to maintain the functional activity of the brain in conditions of neurodegeneration, that is, CCR, require further research and can form a conceptual basis for the prevention of AD, starting from the preclinical stages of the disease.

Cognitive Performance of Latino and White Non-Latino Individuals With Parkinson's Disease

OBJECTIVE

Cognitive impairment is a common nonmotor symptom in Parkinson's disease (PD). Individuals of Latino background are traditionally underrepresented in research on PD. Despite the fact that Latinos comprise 18% of the U.S. population, they commonly make up less than 5% of samples in studies of PD. Emerging evidence suggests that Latino individuals with PD may experience disparities relative to White non-Latinos in terms of having more severe motor symptoms, more severe depressive symptoms, and worse health-related quality of life. The purpose of the present study was to investigate differences in cognitive performance between Latino and White non-Latino individuals with PD and examine correlates of cognitive performance.

METHODS

Data were obtained from the Parkinson's Progression Markers Initiative. Participants included 60 Latino individuals with PD and 1,009 White non-Latino individuals with PD, all of whom were followed annually for up to 5 years. Participants completed neuropsychological tests of attention and working memory, processing speed, visuospatial functioning, verbal fluency, and immediate and delayed memory and recall.

RESULTS

Relative to White non-Latino individuals with PD, Latino individuals with PD had significantly lower scores on the global measure of cognitive functioning, a test of processing speed, and tests of working memory and attention. Years of education was the strongest correlate of performance in these three cognitive domains among individuals in the Latino group.

CONCLUSIONS

These findings provide initial evidence of disparities in cognitive functioning among Latino individuals with PD. Educational disadvantages may be one potential driver of these disparities.

Inequalities in accelerated cognitive decline: Resolving observational window bias using nested non-linear regression

INTRODUCTION

Limited observational windows lead to conflicting results in studies examining educational differences in Alzheimer's disease and related dementias (ADRD) risk, due to observational window bias relative to onset of accelerated cognitive decline. This study tested a novel model to address observational window bias and tested for the presence and sources of disparities in accelerated cognitive declines due to ADRD.

METHODS

The sample examined 167,314 cognitive assessments from 32,441 Health and Retirement Study participants. We implemented a parametric non-linear nested longitudinal regression and reported multivariable-adjusted nodal incidence ratios (aNIR).

RESULTS

University degrees were associated with lower incidence (aNIR = 0.253, 95% confidence interval [CI] = [0.221 to 0.289], p < 0.001), while black participants had a higher incidence (aNIR = 1.995, [1.858 to 2.141], p < 0.001) of accelerated cognitive decline, adjusting for demographic, sociobehavioral, and medical risk factors. Sex-stratified analyses identified diminished educational returns for women and increased incidence among minoritized women.

DISCUSSION

Addressing observational window bias reveals large social inequalities in the onset of accelerated cognitive declines indicative of ADRD.

HIGHLIGHTS

This study identifies observational window bias as a source of conflicting results among previous studies of educational achievement in Alzheimer's disease and related dementias (ADRD) disparities. The study locates preclinical accelerated cognitive decline, which is indicative of ADRD while occurring 10+ years prior to symptom onset, as a site to study ADRD disparities that mitigates observational window bias. A novel method, nested non-linear regression, is developed to test for differences in the onset of accelerated cognitive decline. Educational and racial/ethnic disparities are demonstrated in the onset of accelerated cognitive decline, as are their intersecting differences with sex/gender.

Change in cognitive performance during seven-year follow-up in midlife is associated with sex, age, and education - The Cardiovascular Risk in Young Finns Study

OBJECTIVE

Sex, age, and education are associated with the level of cognitive performance. We investigated whether these factors modulate the change in cognitive performance in midlife by leveraging the longitudinal data from the Cardiovascular Risk in Young Finns Study (YFS).

METHODS

Participants of the YFS cohort performed a computer-based Cambridge Neuropsychological Test Automated Battery (CANTAB) in 2011 and 2018 (n = 1671, age 41-56 years in 2018). Overall cognitive performance and domains representing learning and memory, working memory, reaction time, and information processing were extracted by common principal component analysis from the longitudinal cognitive data. Linear models adjusted for baseline cognitive performance were used to study the association of sex, age, and education with changes in overall cognitive performance and in the cognitive domains.

RESULTS

Cognitive performance decreased in all domains (overall cognition -0.56 SD, p < 0.001; working memory -0.81 SD, p < 0.001; learning and memory -0.70 SD, p < 0.001; reaction time -0.06 SD, p = 0.019; information processing -0.03 SD, p = 0.016). The decrease in working memory and information processing was greater in females compared to males. Cognitive performance decreased more in older participants in all domains. Education alleviated the decrease in cognitive performance in all domains except reaction time. The beneficial effect of education was greater for males.

CONCLUSIONS

This study describes the natural course of aging-related changes in cognitive performance in midlife, the critical time window for early prevention of clinical cognitive decline. These findings provide a reference for studies focusing on determinants of pathological cognitive decline deviating from normal changes in cognitive performance.

Cognitive reserve modulates mental health in adulthood

Cognitive Reserve (CR) reflects acquired knowledge, skills, and abilities throughout life, and it is known for modulating cognitive efficiency in healthy and clinical populations. CR, which was initially proposed to explain individual differences in the clinical presentation of dementia, has subsequently been extended to healthy ageing, showing its role in cognitive efficiency also during middle age. Recently, CR has been linked to affective processes in psychiatric conditions such as schizophrenia, major depressive and anxiety symptoms, and psychological distress, suggesting its potential role in emotional expression and regulation. Whether the role of CR in mental health extends to non-pathological adults, and whether this is only relevant in older age is not yet clear. The aim of this work was therefore to explore the relationship between CR and mental health in healthy adults, with a focus on middle adulthood (40-60). In a sample of 96 participants, we found a positive association between CR and mental health outcomes, such that a higher cognitive reserve index corresponded to fewer mental health reported symptoms. Specifically, a higher CR reflecting professional activities was associated with lower stress levels, especially in middle agers. Taken together, these data therefore suggest that engaging occupations may help maintain a robust mental health, especially by reducing stress symptoms during middle age. These results broaden previous findings suggesting that CR relates to affective components of mental health in middle aged and older adults.

Relationship between low mood and micro-expression processing: evidence of negative bias in interpreting fleeting facial expressions

Depression affects the recognition of emotion in facial expressions by reducing the detection accuracy and adding a bias towards negativity. However, no study has examined associations between depression and the recognition of microfacial expressions (fleeting facial cues of emotions in people's faces). Thus, we investigated associations between low mood and micro-expression processing using video stimuli of micro-expressions. We examined whether (i) individuals with low mood had trouble recognizing emotions, (ii) were more likely to perceive happy facial expressions as neutral and neutral facial expressions as sad, and (iii) recognized sad emotional expressions better than control subjects (n = 349). We found that participants with low mood showed poorer performance when judging emotions in faces (p = 0.03). Furthermore, there was a specific deficit among them in recognizing happiness. Lastly, participants with low moods were more likely to perceive neutral faces as sad (p = 0.042). However, no evidence was found that individuals with low moods confused happy faces as neutral or were better than the control group at recognizing sad faces. Our results show that mood affects the perception of emotions in facial expressions, which has the potential to negatively affect interpersonal interactions and ultimately quality of life.

Sex Differences in the Trajectories of Cognitive Decline and Affected Cognitive Domains Among Older Adults With Controlled and Uncontrolled Glycemia

BACKGROUND

We aimed to analyze the trajectories of cognitive decline as a function of the presence of type 2 diabetes and glycemic control in analyzes stratified by sex in an 8-year follow-up period.

METHODS

A total of 1 752 men and 2 232 women aged ≥50 years who participated in the English Longitudinal Study of Ageing (ELSA), conducted from 2004 to 2012, were analyzed. The outcomes of interest were performance on the cognitive domains of memory, executive function, and temporal orientation as well as the global cognition score. Cognitive performance was standardized in z-scores in strata based on schooling and age. The participants were classified as without diabetes, with controlled glycemia, and with uncontrolled glycemia, according to medical diagnosis, glucose-lowering medications use and HbA1c levels. Generalized linear mixed models controlled by sociodemographic, behavioral, and health-related characteristics were used for the trajectory analyses.

RESULTS

No differences in z-scores were found for global cognition or cognitive domains based on diabetes classification in men and women at baseline. More than 8 years of follow up, women with uncontrolled glycemia had a greater decline in z-scores for global cognition (-0.037 SD/year [95% CI: -0.073; -0.001]) and executive function (-0.049 SD/year [95% CI: -0.092; -0.007]) compared with those without diabetes. No significant difference in trajectories of global cognition or any cognitive domain was found in men as a function of diabetes classification.

CONCLUSIONS

Women with uncontrolled glycemia are at greater risk of a decline in global cognition and executive function than those without diabetes.

How Do Modifiable Risk Factors Affect Alzheimer's Disease Pathology or Mitigate Its Effect on Clinical Symptom Expression?

Epidemiological studies show that modifiable risk factors account for approximately 40% of the population variability in risk of developing dementia, including sporadic Alzheimer's disease (AD). Recent findings suggest that these factors may also modify disease trajectories of people with autosomal-dominant AD. With positron emission tomography imaging, it is now possible to study the disease many years before its clinical onset. Such studies can provide key knowledge regarding pathways for either the prevention of pathology or the postponement of its clinical expression. The former "resistance pathway" suggests that modifiable risk factors could affect amyloid and tau burden decades before the appearance of cognitive impairment. Alternatively, the resilience pathway suggests that modifiable risk factors may mitigate the symptomatic expression of AD pathology on cognition. These pathways are not mutually exclusive and may appear at different disease stages. Here, in a narrative review, we present neuroimaging evidence that supports both pathways in sporadic AD and autosomal-dominant AD. We then propose mechanisms for their protective effect. Among possible mechanisms, we examine neural and vascular mechanisms for the resistance pathway. We also describe brain maintenance and functional compensation as bases for the resilience pathway. Improved mechanistic understanding of both pathways may suggest new interventions.

10-Year Cognitive Change in the Faroese Septuagenarian Cohort and Impact of Sociodemographic, Lifestyle, and Health Factors

OBJECTIVES

To investigate cognitive change in multiple cognitive domains in a population-based cohort of 713 Faroese older adults.

METHODS

Participants were cognitively tested at baseline (70-74 years) and re-evaluated after 10 years. Changes in cognitive performance and the impact of sociodemographic factors, lifestyle, and health conditions were analysed using mixed-effect models. Participants free from dementia were studied in separate analyses.

RESULTS

A significant decline over 10 years was observed in most of the neuropsychological tests. People living in rural areas, married or cohabiting people, people without professional education, slightly older persons, smokers, teetotalers, and people with heart disease and abnormal electrocardiogram (ECG) had a steeper decline in cognitive ability. Conflicting results were found for sex and people with myocardial infarction (MI).

DISCUSSION

There are modifiable factors that contribute to cognitive decline which should be addressed in future public health efforts.

Trajectories of cognitive function among people aged 45 years and older living with diabetes in China: Results from a nationally representative longitudinal study (2011~2018)

OBJECTIVES

Diabetes is associated with decline of cognitive function. Exploring different trajectories of cognitive function occurring in people with diabetes is important to improved prognosis. This study aimed to investigate differential patterns of trajectories of cognitive function and baseline determinants of trajectory group membership utilizing data from middle-aged and older Chinese adults with diabetes.

METHODS

Participants of the Chinese Health And Retirement Longitudinal Study (CHARLS) aged 45 years and above received biennial assessments between 2011 and 2018. The primary outcome was overall cognitive function score operationalized as sum of mental intactness and episodic memory scores derived from the Telephone Interview of Cognitive Status (TICS). A weighted growth mixture model was used to estimate cognitive function trajectories of CHARLS participants with diabetes, and baseline factors associated with trajectory group membership were investigated with weighted multinomial logistic regression.

RESULTS

Data from 1,463 participants with diabetes aged 45 years and above were analyzed, a three-group trajectory model showed the best fit for overall cognitive scores: low baseline, linear declining (22.1%); moderate baseline, linear declining (37.5%) and high-stable (40.3%). Older participants, females, participants with low education, with nighttime sleep <6 h, without daytime napping habits, and with depressive symptoms were at a higher risk of unfavorable cognitive function trajectories.

CONCLUSIONS

We identified heterogeneous trajectories of cognitive function among middle-aged and older people living with diabetes in China. Socially vulnerable groups including females, rural residents, and those with low education were at a higher risk for unfavorable trajectories. In health programs aimed at preventing and mitigating cognitive decline in individuals with diabetes more attention should be given to vulnerable groups. Reduced nighttime sleep, lack of daytime napping, and depressive symptoms appear to be modifiable risk factors.

A Bayesian benchmark concentration analysis for urinary fluoride and intelligence in adults in Guizhou, China

Environmental fluoride exposure has been linked to numerous cases of fluorosis worldwide. Previous studies have indicated that long-term exposure to fluoride can result in intellectual damage among children. However, a comprehensive health risk assessment of fluorosis-induced intellectual damage is still pending. In this research, we utilized the Bayesian Benchmark Dose Analysis System (BBMD) to investigate the dose-response relationship between urinary fluoride (U-F) concentration and Raven scores in adults from Nayong, Guizhou, China. Our research findings indecate a dose-response relationship between the concentration of U-F and intelligence scores in adults. As the benchmark response (BMR) increased, both the benchmark concentration (BMCs) and the lower bound of the credible interval (BMCLs) increased. Specifically, BMCs for the association between U-F and IQ score were determined to be 0.18 mg/L (BMCL1 = 0.08 mg/L), 0.91 mg/L (BMCL5 = 0.40 mg/L), 1.83 mg/L (BMCL10 = 0.83 mg/L) when using BMRs of 1 %, 5 %, and 10 %. These results indicate that U-F can serve as an effective biomarker for monitoring the loss of IQ in population. We propose three interim targets for public policy in preventing interllectual harm from fluoride exposure.

My Parent, Myself, or My Child: Whose Education Matters Most for Trajectories of Cognitive Aging in Middle Age?

The growing body of evidence linking intergenerational education and late-life cognitive decline is almost exclusively from high-income countries, despite rapid intergenerational changes in education in low- and middle-income countries (LMICs). We used data from the Mexican Health and Aging Study (n = 8,822), a cohort study of Mexican adults aged ≥50 years (2001-2018), to evaluate whether parental education (none vs. any formal schooling), one's own education (less than primary school vs. completion of primary school), or an adult child's education (less than high school vs. completion of high school) was associated with verbal memory z scores. We used linear mixed models with inverse probability of attrition weights. Educational attainment in all 3 generations was associated with baseline verbal memory scores, independent of the prior generation's education. Lower parental (β = -0.005, 95% confidence interval: -0.009, -0.002) and respondent (β = -0.013, 95% confidence interval: -0.017, -0.010) educational level were associated with faster decline in delayed (but not immediate) verbal memory z scores. Associations between adult child's education and respondent's verbal memory decline varied by exposure specification. The educational attainment of parents and adult children may influence the cognitive aging of middle-aged and older adults in LMICs. These results have important implications given recent structural shifts in educational attainment in many LMICs.

Handicraft art leisure activities and cognitive reserve

ObjectiveOlder individuals face a higher likelihood of developing dementia. The rate of cognitive decline resulting from dementia is not equivalent for all, as some patients with dementia are able to function independently longer than others, despite having similar disease burden. The cognitive reserve (CR) theory provides one explanation for the differing rate of decline. CR suggests that there are factors-most notably, educational attainment and occupational attainment-that can protect against the cognitive decline. Although the beneficial effects of these notable CR factors are clear, not all are easily modifiable. Participation in leisure activities may represent a more easily modifiable factor. Some research hints at beneficial effects of leisure activities, although specific leisure activities have not been well examined. The present study examined the relations between handicraft art leisure activities (HALAs) and multiple cognitive domains. MethodArchival WAIS-IV and demographic data for 50 California retirement community residents were examined. ResultsHALA participation accounted for statistically significant variance in working memory performance (R2 = .40, β = .24%) over and above the established CR factors of age, depression, educational attainment, and occupational attainment. In addition, HALA participation was related to a better ability to perform abstract visual information tasks (Block Design subtest, r = .28, p = .05) and non-verbal reasoning tasks (Visual Puzzles subtest, r = .38, p = .008). ConclusionsHALA participation among older adults could contribute to the retention of cognitive function, supporting the role of HALA participation as a CR factor.

The Danish Aging and Cognition (DanACo) cohort

BACKGROUND

With aging populations worldwide, identification of predictors of age-related cognitive decline is becoming increasingly important. The Danish Aging and Cognition Cohort (DanACo) including more than 5000 Danish men was established to investigate predictors of age-related cognitive decline from young adulthood to late mid-life.

CONSTRUCTION AND CONTENT

The DanACo cohort was established through two separate data collections with identical designs involving a follow-up examination in late mid-life of men for whom intelligence test scores were available from their mandatory conscription board examination. The cohort consists of 5,183 men born from 1949 through 1961, with a mean age of 20.4 years at baseline and a mean age of 64.4 years at follow-up. The baseline measures consisted of height, weight, intelligence test score and educational level collected at the conscription board examination. The follow-up assessment consisted of a re-administration of the same intelligence test and a comprehensive questionnaire covering socio-demographic factors, lifestyle, and health-related factors. The data were collected in test sessions with up to 24 participants per session. Using the unique personal identification number assigned to all Danes, the cohort has been linked to data from national administrative and health registers for prospectively collected data on socioeconomic and health-related factors.

UTILITY AND DISCUSSION

The DanACo cohort has some major strengths compared to existing cognitive aging cohorts such as a large sample size (n = 5,183 men), a validated global measure of cognitive ability, a long retest interval (mean 44.0 years) and the availability of prospectively collected data from registries as well as comprehensive questionnaire data. The main weakness is the low participation rate (14.3%) and that the cohort consists of men only.

CONCLUSION

Cognitive decline is a result of a summary of factors across the life-course. The DanACo cohort is characterized by a long retest interval and contains data on a wealth of factors across adult life which is essential to establish evidence on predictors of cognitive decline. Moreover, the size of the cohort ensures sufficient statistical power to identify even relatively weak predictors of cognitive decline.

Clinical and neuropsychological characterization of SuperAgers residing in Delhi and National Capital Region of India-A cross-sectional study

Introduction

SuperAgers (SA) are older adults who exhibit cognitive capacities comparable to individuals who are three or more decades younger than them. The current study aimed to identify the characteristics of Indian SA by categorizing 55 older adults into SA and Typical Older Adults (TOA) and comparing their performance with a group of 50 younger participants (YP) (aged 25-50).

Methods

A total of 105 participants were recruited after obtaining informed written consent. The cognitive abilities of the participants were assessed using Wechsler Adult Intelligence Scale (WAIS)-IVINDIA, Color Trails Test, Boston Naming Test (BNT), and Rey Auditory Verbal Learning Test.

Results

SA outperformed TOA in all cognitive assessments (P < 0.001) and surpassed YP in BNT and WAIS-IV. SA's delayed recall scores were notably higher (12.29 ± 1.51) than TOA (6.32 ± 1.44).

Conclusion

SA excelled in all cognitive domains demonstrating resilience to age-related cognitive decline. This study highlights Indian SuperAgers' exceptional cognitive prowess.

African Ancestry Individuals with Higher Educational Attainment Are Resilient to Alzheimer's Disease Measured by pTau181

Background

Cognitive and functional abilities in individuals with Alzheimer's disease (AD) pathology (ADP) are highly variable. Factors contributing to this variability are not well understood. Previous research indicates that higher educational attainment (EA) correlates with reduced cognitive impairments among those with ADP. While cognitive and functional impairments are correlated, they are distinguishable in their manifestations.

Objective

To investigate whether levels of education are associated with functional impairments among those with ADP.

Methods

This research involved 410 African American (AA) individuals (Institutional Review Boards 20070307, 01/27/2023) to ascertain whether EA correlates with functional resilience and if this effect varies between APOE ɛ4 carriers and non-carriers. Utilizing EA as a cognitive reserve proxy, CDR-FUNC as a functional difficulties measure, and blood pTau181 as an ADP proxy, the non-parametric Mann-Whitney U test assessed the relationship between EA and CDR-FUNC in individuals with advanced pTau181 levels.

Results

The results showed that EA correlated with functional difficulties in AA individuals with high levels of pTau181, such that individuals with high EA are more likely to have better functional ability compared to those with lower EA (W = 730.5, p = 0.0007). Additionally, we found that the effect of high EA on functional resilience was stronger in ɛ4 non-carriers compared to ɛ4 carriers (W = 555.5, p = 0.022).

Conclusion

This study extends the role of cognitive reserve and EA to functional performance showing that cognitive reserve influences the association between ADP burden and functional difficulties. Interestingly, this protective effect seems less pronounced in carriers of the strong genetic risk allele ɛ4.

The MAPP Room Memory Test: Examining Contextual Memory Using a Novel Computerized Test in Cognitively-Unimpaired Individuals with Autosomal Dominant Alzheimer's Disease

Contextual memory, the ability to remember spatial or temporal features related to an event, is affected in Alzheimer's disease (AD). There is a shortfall of tests that measure contextual memory. To evaluate visuospatial contextual memory, we developed a computerized cognitive test, the MAPP Room Memory Test, which requires participants to identify in which visual scene target items were previously presented. We hypothesized that cognitively-unimpaired carriers of an autosomal dominant AD mutation (Presenilin-1 E280A, n=15) would perform more poorly on this test than non-carrier family members (n=31). Compared to non-carriers, the carriers had significantly worse delayed room recognition. The results indicate that the MAPP Room Memory Test may be sensitive to subtle cognitive changes associated with risk of AD. Future studies with larger samples using the MAPP Room Memory Test and biomarkers are needed to examine whether this test may also be sensitive to the earliest pathological changes in preclinical AD.

Improved Accuracy of the Addenbrooke's Cognitive Examination-Revised in the Diagnosis of Mild Cognitive Impairment, Mild Dementia Due to Alzheimer's Disease and Behavioral Variant Frontotemporal Dementia Using Mokken Scale Analysis

Background

The Addenbrooke's Cognitive Examination-Revised (ACE-R) is an accessible cognitive tool that supports the early detection of mild cognitive impairment (MCI), Alzheimer's disease (AD), and behavioral variant frontotemporal dementia (bvFTD).

Objective

To investigate the diagnostic efficacy of the ACE-R in MCI, AD, and bvFTD through the identification of novel coefficients for differentiation between these diseases.

Methods

We assessed 387 individuals: 102 mild AD, 37 mild bvFTD, 87 with amnestic MCI patients, and 161 cognitively unimpaired controls. The Mokken scaling technique facilitated the extraction out of the 26 ACE-R items that exhibited a common latent trait, thereby generating the Mokken scales for the AD group and the MCI group. Subsequently, we performed logistic regression, integrating each Mokken scales with sociodemographic factors, to differentiate between AD and bvFTD, as well as between AD or MCI and control groups. Ultimately, the Receiver Operating Characteristic curve analysis was employed to assess the efficacy of the coefficient's discrimination.

Results

The AD-specific Mokken scale (AD-MokACE-R) versus bvFTD exhibited an Area Under the Curve (AUC) of 0.922 (88% sensitivity and specificity). The AD-MokACE-R versus controls achieved an AUC of 0.968 (93% sensitivity, 94% specificity). The MCI-specific scale (MCI-MokACE-R) versus controls demonstrated an AUC of 0.859 (78% sensitivity, 79% specificity).

Conclusions

The ACE-R's capacity is enhanced through statistical methods and demographic integration, allowing for accurate differentiation between AD and bvFTD, as well as between MCI and controls. This new method not only reinforces its clinical value in early diagnosis but also surpasses traditional approaches noted in prior studies.

Cognitive complaints in older adults: relationships between self and informant report, objective test performance, and symptoms of depression

This study explored the relationships between objective measures of cognitive functioning, self and informant reports of cognitive problems in daily life, and depression screening in older adults who had been referred because of reported or suspected cognitive changes. We used archival data from 100, predominantly White (97%), typically educated (M = 13.25 years), older adults (M = 70.38 years) who received an outpatient neuropsychological evaluation. We characterized the cognitive performance using the CVLT-II Total score. We characterized patient and collateral reports using the BRIEF-A MI index, a normed scale of cognitive problems in daily life. We also incorporated a depression screener (PHQ-9) into our analyses. Multiple linear regression analysis revealed that only the informant reported problems in daily life, using the BRIEF-A MI index, was a significant predictor of objective cognitive deficits, as defined by CVLT-II Total scores. Self BRIEF-A MI index scores were not significant predictors of CVLT-II Total performance after we accounted for depression using the patient's PHQ-9 score. Additionally, elevated depression widened the discrepancy between raters, with elevated depression associated with worsening sself-report scores compared to informant-reported scores. As informant-reported problems were the strongest predictor of cognitive deficits, we recommend routine collection of collateral informant reports in the neuropsychological evaluation of older adults referred for cognitive concerns. We also recommend incorporating self-ratings of daily life functioning and screening for depression to contextualize patient complaints and address their concerns, even in the absence of objective cognitive dysfunction.

Timing and level of educational attainment and late-life cognition in the KHANDLE study

INTRODUCTION

The timing of educational attainment may modify its effects on late-life cognition, yet most studies evaluate education only at a single time point.

METHODS

Kaiser Healthy Aging and Diverse Life Experiences (KHANDLE) Study cohort participants (N = 554) reported educational attainment (dichotomized at any college education) at two time points, and we classified them as having low, high, or later-life high educational attainment. Linear mixed-effects models estimated associations between educational attainment change groups and domain-specific cognitive outcomes (z-standardized).

RESULTS

Compared to low educational attainment, high (β= 0.59 SD units; 95% confidence interval [CI]: 0.39, 0.79) and later-life high educational attainment (β = 0.22; 95% CI: 0.00, 0.44) were associated with higher executive function. Only high educational attainment was associated with higher verbal episodic memory (β = 0.27; 95% CI: 0.06, 0.48).

DISCUSSION

Level and timing of educational attainment are both associated with domain-specific cognition. A single assessment for educational attainment may inadequately characterize protective associations with late-life cognition.

HIGHLIGHTS

Few studies have examined both level and timing of educational attainment on cognition. Marginalized populations are more likely to attain higher education in adulthood. Higher educational attainment in late life is also associated with higher cognition.

Attention and processing speed tests: Normative data for Spanish-speaking adults in the United States

BACKGROUND

Hispanics/Latinos are the largest racial/ethnic group among underrepresented populations in the U.S. and multiple sociodemographic, cultural, and linguistic factors have been found to impact their performances on cognitive testing. Despite this, few normative data are available for the heterogeneous Spanish-speaking population in the U.S.

OBJECTIVE

To generate normative data on the Trail-Making Test (TMT), Bells Test, Symbol-Digit Modalities Test (SDMT), and the Brief Test of Attention (BTA) for Spanish speakers residing in the U.S.

METHODS

The sample included 245 Spanish-speaking individuals aged 18- 80 from eight states across the U.S. (California, Connecticut, Florida, Indiana, New Jersey, Oregon, Virginia, and Wisconsin). Participants were administered attention and processing speed measures as part of a comprehensive neuropsychological battery. We used a Bayesian regression approach to estimate normative data, including covariates found to be important for predicting performances on measures of attention and processing speed.

RESULTS

Sociodemographic factors including education, time in the U.S., acculturation, age, and/or sex had differential effects on the TMT-A, TMT-B, SDMT, and the BTA whereas the Bells Test was not influenced by any of these sociodemographic factors.

CONCLUSION

Our findings indicate that while sex, age, and educational attainment are important factors to consider, language and acculturation can also influence attention and processing speed performances among Spanish speakers in the U.S.