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Previous clinical studies have reported adverse cognitive outcomes for people living with HIV (PLWH), but there are no population-based studies comparing cognitive function between older PLWH and comparators without HIV in sub-Saharan Africa. We analyzed baseline data of 40 + years-old participants in "Health and Aging in Africa: A Longitudinal Study of an INDEPTH Community in South Africa" (HAALSI) cohort. We measured cognition using a battery of conventional instruments assessing orientation, immediate- and delayed-recall, and numeracy (N = 4560), and the Oxford Cognitive Screen [OCS]-Plus, a novel instrument for low-literacy populations, assessing memory, language, visual-spatial ability, and executive functioning (N = 1997). Linear regression models comparing cognitive scores between participants with and without HIV were adjusted for sex, education, age, country of birth, father's occupation, ever-consumed alcohol, and asset index. PLWH scored on average 0.06 (95% CI 0.01-0.12) standard deviation (SD) units higher on the conventional cognitive function measure and 0.02 (95% CI - 0.07 to 0.04) SD units lower on the OCS-Plus measure than HIV-negative participants. We found higher cognitive function scores for PLWH compared to people without HIV when using a conventional measure of cognitive function but not when using a novel instrument for low-literacy settings.

Research on early life adversity and later-life cognitive function is conflicting, with little evidence from low-income settings. We investigated associations between adverse childhood experiences and cognitive function in an older population who grew up under racial segregation during South African apartheid. Data were from 1,871 adults aged 40-79 in the population-representative "Health and Ageing in Africa: A Longitudinal Study of an INDEPTH Community in South Africa" in 2015. The adverse childhood experiences were having a parent unemployed for > 6 months; having parents who argued or fought often; having a parent who drank excessively, used drugs, or had mental health problems; and physical abuse from parents. Executive function, language, visuospatial ability, and memory were assessed with the Oxford Cognitive Screen-Plus, a validated cognitive assessment designed for low-income, low-literacy settings. We estimated associations between adverse childhood experiences and latent cognitive domain z-scores using multiple-indicator, multiple-cause structural equation models. Childhood adversities were reported by 15% (parental unemployment for > 6 months), 25% (parents argued or fought often), 25% (a parent drank excessively, used drugs, or had mental health problems), and 35% (physical abuse from parent) of respondents. They were not associated with cognition, except that having a parent who drank excessively, used drugs, or had mental health problems was associated with lower memory z-scores (-0.07; 95% CI [-0.13, -0.01]). This is one of the first investigations into later-life cognitive outcomes associated with early adversity in a population with a historical context of pervasive trauma, and suggests that later-life memory may be vulnerable to early adversity. (PsycInfo Database Record (c) 2020 APA, all rights reserved).

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., (© The Author(s) 2020. Published by Oxford University Press on behalf of The Gerontological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Background: Evidence on cognitive function in older South Africans is limited, with few population-based studies. We aimed to estimate baseline associations between cognitive function and cardiometabolic disease risk factors in rural South Africa., Methods: We use baseline data from "Health and Aging in Africa: A Longitudinal Study of an INDEPTH Community in South Africa" (HAALSI), a population-based study of adults aged 40 and above in rural South Africa in 2015. Cognitive function was measured using measures of time orientation, immediate and delayed recall, and numeracy adapted from the Health and Retirement Study cognitive battery (overall total cognitive score range 0-26). We used multiple linear regression to estimate associations between cardiometabolic risk factors (including BMI, hypertension, dyslipidemia, diabetes, history of stroke, alcohol frequency, and smoking status) and the overall cognitive function score, adjusted for potential confounders., Results: In multivariable-adjusted analyses (n = 3018; male = 1520; female = 1498; median age 59 (interquartile range 50-67)), cardiometabolic risk factors associated with lower cognitive function scores included: diabetes (b = - 1.11 [95% confidence interval: - 2.01, - 0.20] for controlled diabetes vs. no diabetes); underweight BMI (b = - 0.87 [CI: - 1.48, - 0.26] vs. normal BMI); and current and past smoking history compared to never smokers. Factors associated with higher cognitive function scores included: obese BMI (b = 0.74 [CI: 0.39, 1.10] vs. normal BMI); and controlled hypertension (b = 0.53 [CI: 0.11, 0.96] vs. normotensive)., Conclusions: We provide an important baseline from rural South Africa on the associations between cardiometabolic disease risk factors and cognitive function in an older, rural South African population using standardized clinical measurements and cut-offs and widely used cognitive assessments. Future studies are needed to clarify temporal associations as well as patterns between the onset and duration of cardiometabolic conditions and cognitive function. As the South African population ages, effective management of cardiometabolic risk factors may be key to lasting cognitive health.

Background/aims: We aimed to estimate the prevalence of cognitive impairment, and the sociodemographic and comorbid predictors of cognitive function among older, rural South African adults., Methods: Data were from a population-based study of 5,059 adults aged ≥40 years in rural South Africa in 2015. Cognitive impairment was defined as scoring ≤1.5 SDs below the mean composite time orientation and memory score, or requiring a proxy interview with "fair" or "poor" proxy-reported memory. Multiple linear regression estimated the sociodemographic and comorbid predictors of cognitive score, with multiplicative statistical interactions between each of age and sex with education., Results: Cognitive impairment increased with age, from 2% of those aged 40-44 (11/516) to 24% of those aged ≥75 years (214/899). The independent predictors of lower cognitive score were being older, female, unmarried, not working, having low education, low household wealth, and a history of cardiovascular conditions. Education modified the negative associations between female sex, older age, and cognitive function score., Conclusions: The prevalence of cognitive impairment increased with age and is comparable to rates of dementia reported in other sub-Saharan African countries. Age and sex differences in cognitive function scores were minimized as education increased, potentially reflecting the power of even poor-quality education to improve cognitive reserve., (© 2018 S. Karger AG, Basel.)

Rationale: Little research has evaluated the life course drivers of cognitive aging in South Africa., Objectives: We investigated the relationships of self-rated childhood health and father's occupation during childhood with later-life cognitive function score and whether educational attainment mediated these relationships among older South Africans living in a former region of Apartheid-era racial segregation., Methods: Data were from baseline assessments of "Health and Aging in Africa: A Longitudinal Study of an INDEPTH Community" (HAALSI), a population-based study of 5059 men and women aged ≥40 years in 2015 in rural Agincourt sub-district, South Africa. Childhood health, father's occupation during childhood, and years of education were self-reported in study interviews. Cognitive measures assessed time orientation, numeracy, and word recall, which were included in a z-standardized latent cognitive function score variable. Linear regression models adjusted for age, sex, and country of birth were used to estimate the total and direct effects of each childhood risk factor, and the indirect effects mediated by years of education., Results: Poor childhood health predicted lower cognitive scores (total effect = -0.28; 95% CI = -0.35, -0.21, versus good); this effect was not mediated by educational attainment. Having a father in a professional job during childhood, while rare (3% of sample), predicted better cognitive scores (total effect = 0.25; 95% CI = 0.10, 0.40, versus unskilled manual labor, 29% of sample). Half of this effect was mediated by educational attainment. Education was linearly associated with later-life cognitive function score (0.09; 95% CI = 0.09, 0.10 per year achieved)., Conclusion: In this post-Apartheid, rural South African context, older adults with poor self-reported childhood health or whose father worked in unskilled manual labor had relatively poor cognitive outcomes. Educational attainment strongly predicted cognitive outcomes, and appeared to be, in part, a mechanism of social stratification in later-life cognitive health in this context., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

Objectives: 1. Assess validity of the Oxford Cognitive Screen (OCS-Plus), a domain-specific cognitive assessment designed for low-literacy settings, especially in low- and middle-income countries (LMIC); 2. Advance theoretical contributions in cognitive neuroscience in domain-specific cognitive function and cognitive reserve, especially related to dementia., Method: In a cross-sectional study of a sample of 1,402 men and women aged 40-79 in the Health and Aging in Africa: A Longitudinal Study of an INDEPTH Community in South Africa (HAALSI), we administered OCS-Plus along with health and sociodemographic assessments. HAALSI is a representative sample of older adults in Agincourt, South Africa contributing to normative understanding of cognition in LMIC. We report measure distributions, construct and external validity of the OCS-Plus., Results: OCS-Plus has excellent construct and external validity. Intra-class correlations between similar basic measures of orientation in OCS-Plus and in HAALSI assessments was 0.79, and groups of people performing well on the OCS-Plus verbal memory also showed superior performance on HAALSI verbal memory. The OCS-Plus scores showed consistent associations with age and education and domain-specific associations with alcohol and depression. Younger respondents and the more educated did better on all assessments., Discussion: The OCS-Plus represents a major methodological advance in dementia studies in LMICs, and enhances understanding of cognitive aging., (© The Author 2016. Published by Oxford University Press on behalf of The Gerontological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)