Cognitive Function In Later Life Research Articles

Disparities in the Life Course Origins of Dual Functionality.

Although research has identified how stressors are related to either physical or cognitive function in later life, we bridge these literatures by examining dual functionality (neither physical nor cognitive impairment) among Black, White, and Hispanic adults. Using data from the Health and Retirement Study (2006-2016), we investigated whether stressors and resources during childhood and adulthood are related to functional loss at baseline and longitudinally. Analyses revealed that lifetime trauma was associated with dual functionality impairment at baseline, but childhood stressors and everyday discrimination were prospectively associated with loss of dual functionality. Black and foreign-born Hispanic adults experienced earlier loss of dual functionality than White adults, and the effect of childhood stressors on the transition to impairment occurred earlier for U.S.-born Hispanic adults. Findings reveal the influence of exposures in childhood and adulthood on functional health in later life-and how resources may be a counterbalance to functional loss.

High School Curricular Rigor and Cognitive Function among White Older Adults.

Most research on the strong relationship between education and cognitive aging has focused on years of schooling. Using data from the Wisconsin Longitudinal Study-a sample of White persons born in 1939-we explored whether greater curricular rigor in high school was also associated with better cognitive function in later life. We estimated multilevel structural equation models in data from 2,749 participants who attended 308 Wisconsin high schools, graduating in 1957. Independent of academic ability and performance and school-level financial and material resources, a more rigorous high school curriculum was associated with significantly better global cognitive functioning in 2020, when most participants were 81 years old. There was also a significant mediation via eventual degree attainment. The mediation was moderated such that men and participants from high socioeconomic status families benefited most from a rigorous curriculum. We discuss implications for modern educational policy.

Underestimating the Relationship: Unpacking Both Socioeconomic Resources and Cognitive Function and Decline in Midlife to Later Life.

Although there is robust evidence that socioeconomic position influences later-life cognitive function, two issues limit knowledge regarding the nature and magnitude of these relationships and potential policy interventions. First, most social science research tends to treat cognition as a unitary concept despite evidence that cognitive outcomes are not interchangeable. Second, most biomedical research focuses exclusively on education, with limited attention to economic resources despite robust social science theoretical and empirical rationales for their role. Relatedly, there has been limited attention to how these relationships may vary across cohorts, even as educational and economic contexts have changed. Using the Health and Retirement Study (N = 36,494), we show that failing to attend to different facets of cognition, socioeconomic resources, and cohort differences leads to underestimates in the magnitude of educational and economic disparities in cognitive function and decline. This has important implications for appropriate policy interventions to address these disparities.

Solubilized β-Glucan Supplementation in C57BL/6J Mice Dams Augments Neurodevelopment and Cognition in the Offspring Driven by Gut Microbiome Remodeling.

A maternal diet rich in dietary fiber, such as β-glucan, plays a crucial role in the offspring's acquisition of gut microbiota and the subsequent shaping of its microbiome profile and metabolome. This in turn has been shown to aid in neurodevelopmental processes, including early microglial maturation and immunomodulation via metabolites like short chain fatty acids (SCFAs). This study aimed to investigate the effects of oat β-glucan supplementation, solubilized by citric acid hydrolysis, from gestation to adulthood. Female C57BL/6J mice were orally supplemented with soluble oat β-glucan (ObG) or carboxymethyl cellulose (CMC) via drinking water at 200 mg/kg body weight during breeding while the control group received 50 mg/kg body weight of carboxymethyl cellulose. ObG supplementation increased butyrate production in the guts of both dams and 4-week-old pups, attributing to alterations in the gut microbiota profile. One-week-old pups from the ObG group showed increased neurodevelopmental markers similar to four-week-old pups that also exhibited alterations in serum markers of metabolism and anti-inflammatory cytokines. Notably, at 8 weeks, ObG-supplemented pups exhibited the highest levels of spatial memory and cognition compared to the control and CMC groups. These findings suggest a potential enhancement of neonatal neurodevelopment via shaping of early-life gut microbiome profile, and the subsequent increased later-life cognitive function.

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

Few studies have examined the relationship between education and cognition among the oldest-old. 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. 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. Education is associated with cognitive function among the oldest-old and varies by gender and cognitive domain at baseline but not over time. 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.

Disaggregating between- and within-person associations of mastery and cognitive function: age as a moderator

BackgroundMastery may shape the way individuals cope with life challenges and influence cognitive function in later life. Mastery grows out of traumatic experience and could change over the life course. This study examined the within-person and between-person associations of mastery and cognitive function, and if these associations were moderated by age in the United States.MethodData were derived from three time points (2006–2008, 2010–2012, and 2014–2016) of the Health and Retirement Study, with 14,461 adults (aged 51 or above). Cognitive function was measured through a 27-point Telephone Interview Cognitive Screen (TICS). Mastery was measured by a modified Pearlin Mastery Scale. Multilevel modeling was employed to analyze the data.ResultsBoth within-person (β\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$\\beta$$\\end{document}=0.124, SE = 0.023, p < 0.001) and between-person (β\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$\\beta$$\\end{document}=0.089, SE = 0.029, p = 0.002) mastery were significantly associated with cognitive function. Older adults with higher between-person mastery tended to have slower cognitive decline (β\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$\\beta$$\\end{document}=0.063, SE = 0.021, p < 0.001). Moreover, age moderated the within-person (β\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$\\beta$$\\end{document}=0.013, SE = 0.003, p < 0.001) associations between mastery and cognition with a stronger association observed among individuals with older age.ConclusionsThe current study provides evidence for within-person and between-person associations between mastery and global cognition in the United States as well as the moderating role of age. The design of the current study did not directly assess the causal direction between mastery and cognitive function. Future studies could test the directionality of associations between mastery and cognitive function.

Religious Involvement and Cognitive Function Among White, Black, and Hispanic Older Adults.

We examined whether religious involvement was associated with cognitive function among older adults in the 2006-2020 waves of the Health and Retirement Study. Using growth curve analysis, we found the association between religious involvement and cognition varied by facet of religious involvement and race and Hispanic ethnicity. Attending religious services with friends was associated with higher initial levels of cognitive function (b = 0.22, p < .05). For Hispanic older adults, frequent attendance at religious services was associated with a slower rate of cognitive decline (b = 0.16, p < .01). Stratified models by race and Hispanic ethnicity demonstrated that religious salience was associated with lower initial levels of cognitive function among non-Hispanic White adults (b = -0.19, p < .01). We found no association between religious involvement and cognitive function among non-Hispanic Black respondents. In sum, elements of religious involvement are positively or negatively related to cognitive function in later life and vary by race and ethnicity.

School-based racial segregation, social support, and late-life cognitive function in the Study of Healthy Aging in African Americans (STAR).

School-based social support for Black students may mediate or modify the association between school segregation and late-life cognition. Study of Healthy Aging in African Americans participants (n=574) reported segregated school attendance and school-based social support. Associations of segregated schooling with domain-specific cognitive outcomes and effect modification or mediation by school-based social support were evaluated with linear mixed models. Segregated school attendance was associated with increased likelihood of school-based social support. Segregated (vs. desegregated in 6th grade) school attendance was associated with lower executive function (β =-0.18 [-0.34, -0.02]) and semantic memory z-scores (β =-0.31 [-0.48, -0.13]). Social support did not mediate these associations. Estimates for segregated school attendance were attenuated among those who felt supported, although there was limited evidence of statistically significant effect modification. Early-childhood school segregation was associated with poorer cognitive function. Sources of resilience within racialized educational experiences should be further evaluated to bridge inequities. School segregation is a form of structural racism that affected the educational experiences of Black youth with potentially lasting consequences for healthy brain aging. Black students who attended a segregated school experienced greater school-based social support, which may highlight a potential source of resilience and resistance against the effects of racism-related stressors on cognitive function. The estimated adverse association between attending a segregated school on cognition was larger for students without an adult at school who cared about them versus those with an adult at school who cared about them, but estimates were imprecise.

Place of Birth and Cognitive Function Among Older Americans: Findings From the Harmonized Cognitive Assessment Protocol.

Growing evidence suggests that place of birth (PoB) and related circumstances may have long-lasting and multiplicative contributions to various later-life outcomes. However, the specific contributions to different domains of cognitive function in late life remain less understood. This study investigated the extent to which state of birth contributes to a wide range of domains of later-life cognitive function. A nationally representative sample of Americans aged 65 and older (N = 3,333) from the Health and Retirement Study (HRS) Harmonized Cognitive Assessment Protocol (HCAP) was utilized. Cognitive function was assessed in HCAP and linked to HRS state of birth data to explore the contribution of PoB to later-life cognitive disparities. Regression-based Shapley decompositions were employed to quantify this contribution. PoB significantly contributed to all assessed cognitive domains including memory, executive function, language and fluency, visuospatial function, orientation, and general cognitive function. Geographic disparities in cognitive function were evident across PoB, with individuals born in U.S. southern states and foreign-born individuals performing worse than those born in other states. Overall, state of birth accounted for 2.2%-9.7% of the total variance in cognition after adjusting for age, sex, and race/ethnicity. This contribution declined to 2.0%-7.0% after further adjusting for comprehensive socioeconomic and health factors over the life course, and was robust to the control of current state of residence. PoB has lasting contributions to later-life cognition, with significant geographic disparities observed. Addressing these disparities requires more equalized place-based policies, resources, and early-life environments to promote health equity over the life course.

Adverse childhood experiences and cognitive function in later life: the sequential mediating roles of education level and adult loneliness.

This study assesses the impact of adverse childhood experiences (ACEs) on the cognitive function of older adults. Furthermore, it examines the potential underlying mechanism involving education level and the subjective "feeling of loneliness" (FOL). Analyzing a population-based cohort sample from the China Health and Retirement Longitudinal Study database, 8,365 subjects aged 45 or older were interviewed in 2018. Ten ACEs indicators were measured using life history questionnaires assessed at 2014. FOL was assessed using a single item from 10-item Center for Epidemiological Studies Depression Scale (CESD-10). Cognitive function was assessed using a structured questionnaire comprising four dimensions: memory, orientation, computation, and visuospatial abilities. In the fully adjusted model, which accounted for age, gender, marital status, smoke, drink, rural residence, and education levels of both mothers and fathers, the linear regression analysis indicated that ACEs were inversely associated the lower education level (B = -0.058, 95% CI = -0.090, -0.026, p < 0.001), and ACEs were found to be linked to an elevated risk of FOL (B = 0.072, 95% CI = 0.056, 0.089, p < 0.001). In addition, ACEs was not significantly associated with cognitive function (B = -0.047, 95% CI = -0.108, 0.015, p = 0.136), but FOL was significantly associated with cognitive function (B = -0.483, 95% CI = -0.561, -0.404, p < 0.001). Mediation analysis revealed that education level and FOL sequentially and partially mediated the association between ACEs and the total cognitive score, with a proportion mediated of 52.58%. The evaluation of ACEs exposure was based on binary response options. This method limited our ability to explore various dimensions of adversity, such as ages of occurrence, severity, frequency, duration, and the extent of psychological effects at the time. Furthermore, the assessment of loneliness relied on a single item from the CESD-10, introducing a potential source of measurement error. Our study unveils a substantial association between ACEs and education level, as well as with FOL and cognitive function in the older adults. Moreover, education level and FOL serve as sequential mediating factors in the relationship between ACEs and cognitive function.

Cognitive function in Vietnam: the effects of war exposure and social engagement

Objective Vietnam is an LMIC in Asia that is experiencing rising cases of Alzheimer’s disease and related dementias (ADRD). Many Vietnamese adults at risk of ADRD have experienced early-life war exposures, which may have negative impacts on their cognitive function in later years. Methods Our study uses the Vietnam Health and Aging Study (VHAS) to investigate the impact of early-life war exposure on cognitive function in later life while also considering variations in social engagement. The sample consists of 2352 adults aged 60 and older from northern and central Vietnam. Cognitive function, measured by questions from the Mini Mental State Examination (MMSE), and self-rated memory are our dependent variables and five measures related to social engagement serve as independent variables. Results Our results show an association between PTSD symptoms and poorer cognitive function (0.0704, p < 0.05) and self-rated memory (OR = 0.904, p < 0.001; 95%). Similar results are also found among for individuals with lower level of social engagement. Furthermore, several sociodemographic factors exhibit attenuated effects on cognitive function due to variations in social engagement. Conclusion Social engagement is generally beneficial for cognitive health amongst those with early-life war exposure, but it does not necessarily attenuate the effects of trauma.

The associations of socioeconomic position with structural brain damage and connectivity and cognitive functioning: The Maastricht Study

BackgroundSocioeconomic inequalities in cognitive impairment may partly act through structural brain damage and reduced connectivity. This study investigated the extent to which the association of early-life socioeconomic position (SEP) with later-life cognitive functioning is mediated by later-life SEP, and whether the associations of SEP with later-life cognitive functioning can be explained by structural brain damage and connectivity. MethodsWe used cross-sectional data from the Dutch population-based Maastricht Study (n = 4,839; mean age 59.2 ± 8.7 years, 49.8% women). Early-life SEP was assessed by self-reported poverty during childhood and parental education. Later-life SEP included education, occupation, and current household income. Participants underwent cognitive testing and 3-T magnetic resonance imaging to measure volumes of white matter hyperintensities, grey matter, white matter, cerebrospinal fluid, and structural connectivity. Multiple linear regression analyses tested the associations between SEP, markers of structural brain damage and connectivity, and cognitive functioning. Mediation was tested using structural equation modeling. ResultsAlthough there were direct associations between both indicators of SEP and later-life cognitive functioning, a large part of the association between early-life SEP and later-life cognitive functioning was explained by later-life SEP (72.2%). The extent to which structural brain damage or connectivity acted as mediators between SEP and cognitive functioning was small (up to 5.9%). ConclusionsWe observed substantial SEP differences in later-life cognitive functioning. Associations of structural brain damage and connectivity with cognitive functioning were relatively small, and only marginally explained the SEP gradients in cognitive functioning.

State-Level Education Quality and Trajectories of Cognitive Function by Race and Educational Attainment.

Although educational attainment is consistently associated with better cognitive function among older adults, we know little about how education quality is related to cognitive function. This is a key gap in the literature given that the quality of US education improved considerably during the early to mid-20th century as state and federal investment increased. We posit that growing up in states with higher-quality education systems may protect against poor cognitive function, particularly among Black adults and adults who completed fewer years of school. We used prospective data on cognitive function from the Health and Retirement Study linked to historical data on state investment in public schools, restricting our sample to non-Hispanic White and Black adults born between 1914 and 1959 (19,096 White adults and 4,625 Black adults). Using race-stratified linear mixed models, we considered if state-level education quality was associated with level and decline in cognitive function and if these patterns differed by years of schooling and race. Residing in states with higher-resourced education systems during childhood was associated with better cognitive function, particularly among those who completed less than 12 years of schooling, regardless of race. For White adults, higher-resourced state education systems were associated with higher scores of total cognitive function and episodic memory, but there were diminishing returns as resources increased to very high levels. For Black adults, the relationship between state education resources and cognitive function varied by age with positive associations in midlife and generally null or negative associations at the oldest ages. Federal and state investment in public schools may provide students with opportunities to develop important cognitive resources during schooling that translate into better cognitive function in later life, especially among marginalized populations.

Effectiveness of dairy products to protect against cognitive decline in later life: a narrative review.

As the world's population ages the prevalence of age-related health concerns is increasing, including neurodegeneration disorders such as mild cognitive impairment, vascular dementia and Alzheimer's disease. Diet is a key modifiable risk factor for the development of neurodegeneration, likely due to gut-brain axis interactions related to neuroinflammation. Analyses of dietary patterns identified dairy as being part of a cognitively healthy diet; however, its contribution to cognitive outcomes is difficult to discern. This narrative review evaluates the literature to determine whether there is sufficient evidence that the consumption of dairy products helps to maintain cognitive function in later life. A search using the terms (dairy OR milk OR cheese OR yogurt OR yogurt) AND ("mild cognitive impairment" OR dementia OR "Alzheimer's disease") identified 796 articles. After screening and sorting, 23 observational studies and 6 intervention studies were identified. The results of the observational studies implied that the relationship between total dairy consumption and cognitive outcomes is inverse U-shaped, with moderate consumption (1-2 servings per day) being the most beneficial. The analysis of the intake of different types of dairy products indicated that fermented products, particularly cheese, were most likely responsible for the observed benefits. The experimental studies all used dairy-derived peptides produced during fermentation as the dietary intervention, and the results indicated that these could be an effective treatment for early-stage cognitive impairment. Further experimental studies with whole dairy products, particularly fermented dairy, are needed to determine whether the regular consumption of these foods should be recommended to maximize the likelihood of healthy cognitive aging.

The Beneficial, Formative Role of Lifetime Exposures across Cognitive Domains in Barbados Using Data from the SABE Study.

This study tested the hypothesis that within older Barbadian adults, sex, education, and occupation type lessen age-related cognitive decline. The analyses used a cross-sectional data set from 1325 people collected in the 2006 SABE Study (Health, Well-being, and Aging). Cognition was assessed as scores in each subdomain of the Mini-Mental State Exam. The loss of a single point in each subdomain was predicted by sex, years of education, job type, and their interactions with age. Results demonstrated that age and protective factors affect each cognitive domain differently. High education combined with mentally complex employment helped maintain cognitive performance in later life. Beneficial lifetime exposures are additive, providing combined benefits. Findings provide insight into public policy aiming to minimize the number of adults with cognitive decline and dementia in Barbados and the Caribbean.

Separating the Effects of Transitions Into and Out of Social Isolation and Loneliness on Cognitive Function in Later Life.

This study investigates the effects of social isolation and loneliness on cognitive function, distinguishing between the effects of transitioning into and out of these states. This study analyzed data from 6,663 adults aged 65 or older collected over the course of 7 waves (12 years) of the Korean Longitudinal Study of Aging from 2006 to 2018. A novel asymmetric fixed effects model was utilized to separately estimate the effects of transitions into and out of social isolation or loneliness. The association of transitions into social isolation due to a lack of informal social contact or loneliness with cognitive function (b = -1.387, p < .001 and b = -0.601, p < .001, respectively) was stronger than the association of transitions out of these states (b = 0.345, p < .05 and b = 0.353, p < .001, respectively). The magnitude of the negative and positive coefficients was statistically different (F-statistic = 45.29, p < .001 and F-statistic = 5.12, p < .05, respectively). In contrast, no such asymmetric effects were observed for social isolation due to a lack of formal activity (F-statistic = 0.06, p = .800). The detrimental effects of transitioning into social isolation due to a lack of informal social contact (but not formal activity) or loneliness on cognitive function outweigh the beneficial effects of transitioning out of these states. Preventing the onset of social disconnection should be prioritized as an intervention to improve the cognitive function of older adults.

Trajectories of Occupational Cognitive Demands and Risk of Mild Cognitive Impairment and Dementia in Later Life: The HUNT4 70+ Study.

The cognitive reserve hypothesis posits that cognitively stimulating work delays the onset of mild cognitive impairment (MCI) and dementia. However, the effect of occupational cognitive demands across midlife on the risk of these conditions is unclear. Using a cohort study design, we evaluated the association between registry-based trajectories of occupational cognitive demands from ages 30-65 years and clinically diagnosed MCI and dementia in participants in the HUNT4 70+ Study (2017-19). Group-based trajectory modeling identified trajectories of occupational cognitive demands, measured by the routine task intensity (RTI) index (lower RTI indicates more cognitively demanding occupation) from the Occupational Information Network. Multinomial regression was implemented to estimate the relative risk ratios (RRRs) of MCI and dementia, after adjusting for age, sex, education, income, baseline hypertension, obesity, diabetes, psychiatric impairment, hearing impairment, loneliness, smoking status, and physical inactivity assessed at HUNT1-2 in 1984-1986 and 1995-1997. To handle missing data, we used inverse probability weighting to account for nonparticipation in cognitive testing and multiple imputation. Based on longitudinal RTI scores for 305 unique occupations, 4 RTI trajectory groups were identified (n = 7,003, 49.8% women, age range 69-104 years): low RTI (n = 1,431, 20.4%), intermediate-low RTI (n = 1,578, 22.5%), intermediate-high RTI (n = 2,601, 37.1%), and high RTI (n = 1,393, 19.9%). Participants in the high RTI group had a higher risk of MCI (RRR 1.74, 95% CI 1.41-2.14) and dementia (RRR 1.37, 95% CI 1.01-1.86), after adjusting for age, sex, and education compared with participants in the low RTI group. In a sensitivity analysis, controlling for income and baseline health-related factors, the point estimates were not appreciably changed (RRR 1.66, 95% CI 1.35-2.06 for MCI, and RRR 1.31, 95% CI 0.96-1.78 for dementia). People with a history of cognitively stimulating occupations during their 30s, 40s, 50s, and 60s had a lower risk of MCI and dementia older than 70 years, highlighting the importance of occupational cognitive stimulation during midlife for maintaining cognitive function in old age. Further research is required to pinpoint the specific occupational cognitive demands that are most advantageous for maintaining later-life cognitive function.

Subjective sleep more predictive of global cognitive function than objective sleep in older adults: A specification curve analysis

ObjectivesSleep is associated with cognitive function in older adults. In the current study, we examined this relationship from subjective and objective perspectives, and determined the robustness and dimensional specificity of the associations using a comprehensive modelling approach. MethodsMultiple dimensions of subjective (sleep quality and daytime sleepiness) and objective sleep (sleep stages, sleep parameters, sleep spindles, and slow oscillations), as well as subjectively reported and objectively measured cognitive function were collected from 55 older adults. Specification curve analysis was used to examine the robustness of correlations for the effects of sleep on cognitive function. ResultsRobust associations were found between sleep and objectively measured cognitive function, but not with subjective cognitive complaints. In addition, subjective sleep showed robust and consistent associations with global cognitive function, whereas objective sleep showed a more domain-specific association with episodic memory. Specifically, subjective sleep quality and daytime sleepiness correlated with global cognitive function, and objective sleep parameters correlated with episodic memory. ConclusionsOverall, associations between sleep and cognitive function in older adults depend on how they are measured and which specific dimensions of sleep and domains of cognitive function are considered. It highlights the importance of focusing on specific associations to ameliorate the detrimental effects of sleep disturbance on cognitive function in later life.

Post-traumatic growth in later-life cognitive function? Evidence from the 1976 Great Tangshan Earthquake.

This study aimed to explore the long-term impacts of exposure to earthquake in adolescence on later-life cognitive function in China. Data were from the 2015 China Health and Retirement Longitudinal Study (CHARLS). Our analytical sample comprised 4394 participants aged 49 to 78 from two birth cohorts born between 1937 and 1966: exposed cohort during adolescence (born between 1952 and 1966), and non-exposed cohort during adolescence (born between 1937 and 1951). We defined earthquake exposure as the exposure severity of the 1976 Great Tangshan Earthquake (GTE). We selected community environmental characteristics as our key moderators. A difference-in-differences (DID) method was employed to estimate the long-term impact of the GTE on later-life cognitive function. We found that exposure to the earthquake during adolescence resulted in higher scores of later-life cognitive function (for males: β = 2.18; 95% CI: 0.70-3.66; for females: β = 1.22; 95% CI: 0.11-2.33). For males, this impact was moderated by community environmental characteristics including the old-age allowance program (β = 3.07; 95% CI: 1.94-4.19) and the condition of basic community infrastructures (β = 1.52; 95% CI: 0.84-2.19). Our study supports the post-traumatic growth theory. This finding suggest that individuals with early-life traumatic exposure need to be focused on. Additionally, improving the conditions of community infrastructures and establishing a community environment with comfort and security may be pretty important for promoting cognitive function and post-traumatic growth.

Late Life Cognitive Function Trajectory Among the Chinese Oldest-Old Population—A Machine Learning Approach

ABSTRACT Informed by the biopsychosocial framework, our study uses the Chinese Longitudinal Healthy Longevity Survey (CLHLS) dataset to examine cognitive function trajectories among the oldest-old (80+). Employing K-means clustering, we identified two latent groups: High Stability (HS) and Low Stability (LS). The HS group maintained satisfactory cognitive function, while the LS group exhibited consistently low function. Lasso regression revealed predictive factors, including socioeconomic status, biological conditions, mental health, lifestyle, psychological, and behavioral factors. This data-driven approach sheds light on cognitive aging patterns and informs policies for healthy aging. Our study pioneers non-parametric machine learning methods in this context.