Disparity in Educational Attainment Partially Explains Cognitive Gender Differences in Older Rural South Africans

Abstract Objectives Direction and magnitude of gender differences in late-life cognitive function are inextricably tied to sociocultural context. Our study evaluates education and literacy as primary drivers of gender equality in cognitive performance among middle-aged and older adults in rural South Africa. Method Data were collected on 1,938 participants aged 40–79 from Agincourt, South Africa. Cognitive function was measured via the Oxford Cognitive Screen-Plus, a tablet-based assessment with low literacy demands. Four cognitive domains were derived through confirmatory factor analysis: episodic memory, executive function, visual spatial, and language. Structural equation models tested domain-specific gender effects, incrementally controlling for demographic, education, health, and socioeconomic variables. Results In the model adjusting only for demographic factors, men outperformed women on executive function and visual-spatial domains. Adding education and literacy to the model revealed a robust female advantage in episodic memory, and reduced the magnitude of male advantage in executive function and visual and spatial by 47% and 42%, respectively. Health and socioeconomic factors did not alter patterns of gender associations in subsequent models. Discussion In this older South African cohort, gender inequality in cognitive performance was partially attributable to educational differences. Understanding biopsychosocial mechanisms that promote cognitive resilience in older women is critically important given the predominantly female composition of aging populations worldwide.

Download Full-text

Poorer Visual Acuity Is Associated with Declines in Cognitive Performance Across Multiple Cognitive Domains: The Maine-Syracuse Longitudinal Study

Journal of the International Neuropsychological Society ◽

10.1017/s1355617718000358 ◽

2018 ◽

Vol 24 (7) ◽

pp. 746-754 ◽

Cited By ~ 3

Author(s):

Peter J. Dearborn ◽

Merrill F. Elias ◽

Kevin J. Sullivan ◽

Cara E. Sullivan ◽

Michael A. Robbins

Keyword(s):

Visual Acuity ◽

Longitudinal Study ◽

Cognitive Function ◽

Episodic Memory ◽

Cognitive Performance ◽

Spatial Organization ◽

Disease Risk ◽

Community Dwelling ◽

Visual Spatial ◽

Verbal Episodic Memory

AbstractObjectives: Prior studies have found associations between visual acuity (VA) and cognitive function. However, these studies used a limited range of cognitive measures and did not control for cardiovascular disease risk factors (CVD-RFs) and baseline function. The primary objective of this study was to analyze the associations of VA and cognitive performance using a thorough neuropsychological test battery. Methods: This study used community-dwelling sample data across the sixth (2001–2006) and seventh (2006–2010) waves of the Maine-Syracuse Longitudinal Study (n=655). Wave 6 VA as measured by the Snellen Eye Test was the primary predictor of wave 6 and wave 7 Global cognitive performance, Visual-Spatial Organization and Memory, Verbal Episodic Memory, Working Memory, Scanning and Tracking, and Executive Function. Additionally, VA was used to predict longitudinal changes in wave 7 cognitive performance (wave 6 performance adjusted). We analyzed these relationships with multiple linear and logistic regression models adjusted for age, sex, education, ethnicity, depressive symptoms, physical function deficits in addition to CVD-RFs, chronic kidney disease, homocysteine, continuous systolic blood pressure, and hypertension status. Results: Adjusted for demographic covariates and CVD-RFs, poorer VA was associated with concurrent and approximate 5-year declines in Global cognitive function, Visual-Spatial Organization and Memory, and Verbal Episodic Memory. Discussion: VA may be used in combination with other screening measures to determine risk for cognitive decline. (JINS, 2018, 24, 1–9)

Download Full-text

Subjective social position and cognitive function in a longitudinal cohort of older, rural South African adults, 2014–2019

Journal of Epidemiology & Community Health ◽

10.1136/jech-2021-217059 ◽

2021 ◽

pp. jech-2021-217059

Author(s):

Lindsay C Kobayashi ◽

Emily P Morris ◽

Guy Harling ◽

Meagan T Farrell ◽

Mohammed U Kabeto ◽

...

Keyword(s):

South Africa ◽

Cognitive Function ◽

Episodic Memory ◽

Low Income ◽

Social Position ◽

Rural South ◽

Cognitive Score ◽

Subjective Social Position ◽

The Relationship

BackgroundThe relationship between subjective social position (SSP) and cognitive ageing unclear, especially in low-income settings. We aimed to investigate the relationship between SSP and cognitive function over time among older adults in rural South Africa.MethodsData were from 3771 adults aged ≥40 in the population-representative ‘Health and Ageing in Africa: A Longitudinal Study of an INDEPTH Community in South Africa’ from 2014/2015 (baseline) to 2018/2019 (follow-up). SSP was assessed at baseline with the 10-rung MacArthur Network social position ladder. Outcomes were composite orientation and episodic memory scores at baseline and follow-up (range: 0–24). Mortality- and attrition-weighted linear regression estimated the associations between baseline SSP with cognitive scores at each of the baseline and follow-up. Models were adjusted for age, age2, sex, country of birth, father’s occupation, education, employment, household assets, literacy, marital status and health-related covariates.ResultsSSP responses ranged from 0 (bottom ladder rung/lowest social position) to 10 (top ladder rung/highest social position), with a mean of 6.6 (SD: 2.3). SSP was positively associated with baseline cognitive score (adjusted β=0.198 points per ladder rung increase; 95% CI 0.145 to 0.253) and follow-up cognitive score (adjusted β=0.078 points per ladder rung increase; 95% CI 0.021 to 0.136).ConclusionIndependent of objective socioeconomic position measures, SSP is associated with orientation and episodic memory scores over two time points approximately 3 years apart among older rural South Africans. Future research is needed to establish the causality of the observed relationships, whether they persist over longer follow-up periods and their consistency in other populations.

Download Full-text

Effects of physical activity on cognitive function among patients with diabetes in China: a nationally longitudinal study

BMC Public Health ◽

10.1186/s12889-021-10537-x ◽

2021 ◽

Vol 21 (1) ◽

Author(s):

Anying Bai ◽

Liyuan Tao ◽

Jia Huang ◽

Jing Tao ◽

Jue Liu

Keyword(s):

Physical Activity ◽

Executive Function ◽

Longitudinal Study ◽

Cognitive Function ◽

Episodic Memory ◽

Age Groups ◽

Screening Tools ◽

Diabetic Patients ◽

Patients With Diabetes ◽

Lagged Dependent Variable

Abstract Background We aimed to examine the effect of physical activity on different cognitive domains among patients with diabetes. Methods We used two waves of data from the Chinese Health and Retirement Longitudinal Study (CHARLS, 2013–2015), a nationally representative dataset of Chinese population aged over 45. Total physical activity scores were calculated based on the International Physical Activity Questionnaire (IPAQ). Executive function and episodic memory were used as measures of cognitive function. We conducted lagged dependent variable models to explore the association between physical activity and cognitive function in full sample as well as two different age groups (45–65, ≥65). Results: 862 diabetic patients were included. We found that diabetic participants who had greater level of physical activity at baseline were associated with better episodic memory function in 2 years (p < 0.05). Moreover, physical activity was significantly associated with less decline in episodic memory in fully adjusted models, and the associations were stronger among patients aged 45–65 years (p < 0.05). No statistically significant association was found between physical activity and executive function in all age groups. Conclusions Physical activity may prevent some of the potential decline in episodic memory in diabetic patients. Clinicians and public health departments should strengthen the promotion of physical activity and develop early screening tools among diabetic participants to prevent the progression of cognitive impairment.

Download Full-text

Racial Disparities in Cognitive Function: The Roles of Cumulative Stress Exposures Across the Life Course

Innovation in Aging ◽

10.1093/geroni/igaa057.1627 ◽

2020 ◽

Vol 4 (Supplement_1) ◽

pp. 504-504

Author(s):

Ruijia Chen ◽

Jennifer Weuve ◽

Laura Kubzansky ◽

David Williams

Keyword(s):

Executive Function ◽

Cognitive Function ◽

Episodic Memory ◽

Life Course ◽

Racial Disparities ◽

The United States ◽

Coping Resources ◽

Age Group ◽

Cumulative Stress ◽

The Life Course

Abstract Introduction: Racial disparities in cognitive function have been well-documented in the literature, but factors driving the disparities remain under explored. This study aims to quantify the extent to which cumulative stress exposures across the life course explain Black–White disparities in executive function and episodic memory. Method: Data were drawn from the 2004–2006 wave of the Midlife Development in the United States (MIDUS) and the MIDUS refresher study (N=5,967, 5,277 White, 690 Black). Cumulative stress exposures were assessed by using 10 domains of stressors (e.g., financial stress, childhood adversity). Cognitive function was assessed using the Brief Test of Adult Cognition by Telephone. Marginal structural models were conducted to quantify the proportion of the effect of race/ethnicity status on cognitive function that can be explained by cumulative stress exposures. Result: Blacks reported higher levels of cumulative stress exposures and lower average levels of executive function and episodic memory than Whites. Cumulative stress exposures explained 8.43% of the disparities in executive function and 13.21 % of the disparities in episodic memory. Cumulative stress exposures had stronger effects on racial disparities in cognitive function in the older age group (age≥ 55 years old) than in the younger age group (age < 55 years old). Conclusion: Cumulative stress exposures explain modest proportions of racial disparities in levels of cognitive function. Interventions that focus on reducing stress exposures or improving coping resources among Blacks may help lessen racial disparities in cognitive function at the population level.

Download Full-text

Slow Wave Sleep and EEG Delta Spectral Power are Associated with Cognitive Function in Parkinson’s Disease

Journal of Parkinson s Disease ◽

10.3233/jpd-202215 ◽

2020 ◽

pp. 1-12

Author(s):

Kimberly H. Wood ◽

Adeel A. Memon ◽

Raima A. Memon ◽

Allen Joop ◽

Jennifer Pilkington ◽

...

Keyword(s):

Executive Function ◽

Cognitive Function ◽

Cognitive Performance ◽

Slow Wave ◽

Effect Size ◽

Processing Speed ◽

Slow Wave Sleep ◽

Spectral Power ◽

Z Scores ◽

Domain Scores

Background: Cognitive and sleep dysfunction are common non-motor symptoms in Parkinson’s disease (PD). Objective: Determine the relationship between slow wave sleep (SWS) and cognitive performance in PD. Methods: Thirty-two PD participants were evaluated with polysomnography and a comprehensive level II neurocognitive battery, as defined by the Movement Disorders Society Task Force for diagnosis of PD-mild cognitive impairment. Raw scores for each test were transformed into z-scores using normative data. Z-scores were averaged to obtain domain scores, and domain scores were averaged to determine the Composite Cognitive Score (CCS), the primary outcome. Participants were grouped by percent of SWS into High SWS and Low SWS groups and compared on CCS and other outcomes using 2-sided t-tests or Mann-Whitney U. Correlations of cognitive outcomes with sleep architecture and EEG spectral power were performed. Results: Participants in the High SWS group demonstrated better global cognitive function (CCS) (p = 0.01, effect size: r = 0.45). In exploratory analyses, the High SWS group showed better performance in domains of executive function (effect size: Cohen’s d = 1.05), language (d = 0.95), and processing speed (d = 1.12). Percentage of SWS was correlated with global cognition and executive function, language, and processing speed. Frontal EEG delta power during N3 was correlated with the CCS and executive function. Cognition was not correlated with subjective sleep quality. Conclusion: Increased SWS and higher delta spectral power are associated with better cognitive performance in PD. This demonstrates the significant relationship between sleep and cognitive function and suggests that interventions to improve sleep might improve cognition in individuals with PD.

Download Full-text

Thalamic Volume Mediates Associations Between Cardiorespiratory Fitness and Memory in People With Parkinson’s

Innovation in Aging ◽

10.1093/geroni/igaa057.1619 ◽

2020 ◽

Vol 4 (Supplement_1) ◽

pp. 501-502

Author(s):

Andrew Petkus ◽

Megan Gomez ◽

Dawn Schiehser ◽

Vincent Filoteo ◽

Jennifer Hui ◽

...

Keyword(s):

Basal Ganglia ◽

Executive Functioning ◽

Episodic Memory ◽

Cognitive Performance ◽

Cardiorespiratory Fitness ◽

Indirect Effect ◽

Structural Equation Models ◽

Intracranial Volume ◽

Vo2 Max ◽

Basal Ganglia Structures

Abstract Cognitive deficits occur in patients with Parkinson’s disease (PD), and cardiorespiratory fitness (CRF) is associated with both current and future cognitive decline in this disease. The underlying neurobiological factors explaining this relationship, however, are not well known. In this cross-sectional study we examined the associations between CRF and cognitive performance and whether such associations were mediated by grey matter volumes of basal ganglia structures. A total of 33 individuals with PD underwent structural magnetic resonance imaging (sMRI), CRF evaluation (VO2max), and neuropsychological assessment. Composite scores of episodic memory, executive functioning, attention, language, and visuospatial functioning were generated. Brain MRI morphological measurements was performed with the Freesurfer image analysis suite. Structural equation models were constructed to examine whether sMRI volume estimates of basal ganglia structures, specifically the thalamus and pallidum, mediated associations between VO2 max and cognitive performance while adjusting for age, education, PD disease duration, sex, and intracranial volume. Higher VO2max was associated with better episodic memory (Standardized β=0.390; p=0.009), executive functioning (Standardized β=0.263; p=0.021), and visuospatial performance (β=0.408; p=0.004). Higher VO2max was associated with larger thalamic (Standardized β=0.602; p<0.001) and pallidum (Standardized β=0.539; p<0.001) volumes. Thalamic volume significantly mediated the association between higher VO2max and better episodic memory (indirect effect=0.209) and visuospatial ability (indirect effect=0.178) performance (p<.05). The pallidum did not significantly mediate associations between VO2 max and cognitive outcomes. These results suggest the thalamus plays an important role in the association between CRF episodic memory and visuospatial functioning in individuals with PD.

Download Full-text

Cognitive Function and Impairment in Older, Rural South African Adults: Evidence from “Health and Aging in Africa: A Longitudinal Study of an INDEPTH Community in Rural South Africa”

Neuroepidemiology ◽

10.1159/000493483 ◽

2018 ◽

Vol 52 (1-2) ◽

pp. 32-40 ◽

Cited By ~ 7

Author(s):

Lindsay C. Kobayashi ◽

Farrah J. Mateen ◽

Livia Montana ◽

Ryan G. Wagner ◽

Kathleen Kahn ◽

...

Keyword(s):

South Africa ◽

Longitudinal Study ◽

Cognitive Function ◽

South African ◽

Rural South ◽

Rural South Africa

Download Full-text

Association of AKAP6 and MIR2113 with cognitive performance in a population based sample of older adults

10.1101/070409 ◽

2016 ◽

Author(s):

Shea J. Andrews ◽

Debjani Das ◽

Kaarin J. Anstey ◽

Simon Easteal

Keyword(s):

Older Adults ◽

Working Memory ◽

Cognitive Function ◽

Episodic Memory ◽

Cognitive Performance ◽

Cognitive Change ◽

European Ancestry ◽

Substantial Contribution ◽

Perceptual Speed ◽

Cognitive Domains

AbstractGenetic factors make a substantial contribution to inter-individual variability in cognitive function. A recent meta-analysis of genome-wide association studies identified two loci, AKAP6 and MIR2113 that are associated with general cognitive function. Here, we extend this previous research by investigating the association of MIR2113 and AKAP6 with baseline and longitudinal nonlinear change across a broad spectrum of cognitive domains in community-based cohort of 1,570 older adults without dementia. Two SNPs, MIR211-rs10457441 and AKAP6-rs17522122 were genotyped in 1,570 non-demented older Australians of European ancestry, who were examined up to 4 times over 12 years. Linear mixed effects models were used to examine the association between AKAP6 and MIR2113 with cognitive performance in episodic memory, working memory, vocabulary, perceptual speed and reaction time at baseline and with linear and quadratic rates of change. AKAP6-rs17522122*T was associated with worse baseline performance in episodic memory, working memory, vocabulary and perceptual speed, but it was not associated with cognitive change in any domain. MIR2113-rs10457441*T was associated with accelerated decline in episodic memory. No other associations with baseline cognitive performance or with linear or quadratic rate or cognitive changes was observed for this SNP. These results confirm the previous finding that, AKAP6 is associated with performance across multiple cognitive domains at baseline but not with cognitive decline, while MIR2113 primarily affects the rate at which memory declines over time.

Download Full-text

Abstract P268: Greater Cognitive Impairment Among Older Adults With Type 1 Diabetes as Compared to Non-diabetic Controls: Results From the Study of Longevity in Diabetes (SOLID)

Circulation ◽

10.1161/circ.141.suppl_1.p268 ◽

2020 ◽

Vol 141 (Suppl_1) ◽

Author(s):

Mary E Lacy ◽

Paola Gilsanz ◽

Chloe Eng ◽

Michal S Beeri ◽

Andrew J Karter ◽

...

Keyword(s):

Older Adults ◽

Type 1 Diabetes ◽

Cognitive Impairment ◽

Executive Function ◽

Cognitive Function ◽

Episodic Memory ◽

Regression Models ◽

Cognitive Test ◽

Race Ethnicity

Introduction: Studies have shown poorer cognitive function in children and adolescents with type 1 diabetes (T1D) as compared to non-diabetic peers. However, little is known about cognitive function in older adults with T1D. Hypothesis: We hypothesized that older adults with T1D and type 2 diabetes (T2D) would have greater cognitive impairment than age, sex, race/ethnicity, and education-matched controls without diabetes. Methods: We compared baseline cognitive impairment among older adults (aged ≥60) from the Study of Longevity in Diabetes (SOLID) with T1D (n=771), T2D (=234) and no diabetes (n=253). Cognitive tests assessed three cognitive domains identified via factor analysis (language, executive function, episodic memory). All cognitive test scores were standardized and cognitive impairment was defined as 1.5 SD below the mean. In logistic regression models adjusted for age, sex, education, and race/ethnicity, we examined the association between diabetes status (T1D, T2D or no diabetes) and cognition on each cognitive domain and on global cognition (average of scores on the 3 domains). Results: In adjusted regression models, compared to older adults without diabetes, those with T1D were more likely to have impaired cognitive function on the language (OR=2.13, 95% CI: 1.08, 4.17) and executive function domains (OR=2.66, 95% CI: 1.36, 5.22). No significant differences in global cognitive impairment or impairment on the episodic memory domain were observed for T1D and no significant differences on any domain were observed for T2D. Conclusions: Our findings suggest that older adults with T1D have greater cognitive impairment than their peers without diabetes; findings were specific to the language and executive function domains, with episodic memory being unaffected. No increase in cognitive impairment was observed for older adults with T2D. Additional research is needed to understand the causes and potentially modifiable factors associated with impaired cognition among older adults with T1D.

Download Full-text