Estimating dementia prevalence using remote diagnoses and algorithmic modelling: a population-based study of a rural region in South Africa.

Background: Dementia is a leading cause of global death and disability. High-quality data describing dementia prevalence and burden remain scarce in sub-Saharan Africa. Health and Aging in Africa: A Longitudinal Study in South Africa (HAALSI) fills evidence gaps with longitudinal data on cognition, biomarkers, and everyday function in a population-based cohort of Black South Africans, aged 40 years and older, in a rural subdistrict.

Mid-Life Household Food Insecurity and Subsequent Memory Function and Rate of Decline in Rural South Africa, 2004-2022.

Introduction: We aimed to investigate mid-life food insecurity over time in relation to subsequent memory function and rate of decline in Agincourt, rural South Africa.

Methods: Data from the longitudinal Agincourt Health and Socio-Demographic Surveillance System (Agincourt HDSS) were linked to the population-representative Health and Aging in Africa: A Longitudinal Study of an INDEPTH Community in South Africa (HAALSI). Food insecurity (yes vs.

Mid-life employment trajectories and subsequent memory function and rate of decline in rural South Africa, 2000-22.

Aim: To investigate mid-life employment trajectories in relation to later-life memory function and rate of decline in rural South Africa.

Methods: Data from the Agincourt Health and Socio-Demographic Surveillance System were linked to the 'Health and Ageing in Africa: A Longitudinal Study of an INDEPTH Community in South Africa' (HAALSI) in rural Agincourt, South Africa (N = 3133). Employment was assessed every 4 years over 2000-12 as being employed (0, 1, 2 and ≥3 time points), being employed in a higher-skill occupation (0, 1, 2 and ≥3 time points) and dynamic employment trajectories identified using sequence analysis.

Associations between cohort derived dementia and COVID-19 serological diagnosis among older Black adults in rural South Africa.

Objectives: This study investigates the association between cohort derived dementia and serologically confirmed SARS-CoV-2 infection, an underexplored phenomena in low-and middle-income countries. Examining this relationship in a rural South African community setting offers insights applicable to broader healthcare contexts.

Methods: Data were collected from Black South Africans in the Mpumalanga province who participated in the Health and Aging in Africa: A Longitudinal Study of an INDEPTH Community in South Africa.

Association of brain arterial diameters with demographic and anatomical factors in a multi-national pooled analysis of cohort studies.

Background And Purpose: Brain arterial diameters are markers of cerebrovascular disease. Demographic and anatomical factors may influence arterial diameters. We hypothesize that age, sex, height, total cranial volume (TCV), and persistent fetal posterior cerebral artery (fPCA) correlate with brain arterial diameters across populations.

Telomere Length, Health, and Mortality in a Cohort of Older Black South African Adults.

Telomere length (TL) may be a biomarker of aging processes as well as age-related diseases. However, most studies of TL and aging are conducted in high-income countries. Less is known in low- and middle-income countries (LMICs) such as South Africa, where life expectancy remains lower despite population aging.

Towards a consensus definition of allostatic load: a multi-cohort, multi-system, multi-biomarker individual participant data (IPD) meta-analysis.

Background: Allostatic load (AL) is a multi-system composite index for quantifying physiological dysregulation caused by life course stressors. For over 30 years, an extensive body of research has drawn on the AL framework but has been hampered by the lack of a consistent definition.

Methods: This study analyses data for 67,126 individuals aged 40-111 years participating in 13 different cohort studies and 40 biomarkers across 12 physiological systems: hypothalamic-pituitary-adrenal (HPA) axis, sympathetic-adrenal-medullary (SAM) axis, parasympathetic nervous system functioning, oxidative stress, immunological/inflammatory, cardiovascular, respiratory, lipidemia, anthropometric, glucose metabolism, kidney, and liver.

Feasibility of an online consensus approach for the diagnosis of cognitive impairment and dementia in rural South Africa.

Introduction: We describe the development and feasibility of using an online consensus approach for diagnosing cognitive impairment and dementia in rural South Africa.

Methods: Cognitive assessments, clinical evaluations, and informant interviews from Cognition and Dementia in the Health and Aging in Africa Longitudinal Study (HAALSI Dementia) were reviewed by an expert panel using a web-based platform to assign a diagnosis of cognitively normal, mild cognitive impairment (MCI), or dementia.

Results: Six hundred thirty-five participants were assigned a final diagnostic category, with 298 requiring adjudication conference calls.

Associations between cognitive function and marital status in the United States, South Africa, Mexico, and China.

We investigate the associations between marital status and cognitive well-being among adults aged 50 and older across four settings: the United States, rural South Africa, Mexico, and China. Using a standardized measure of immediate word recall, we assess whether people in each non-married status have worse cognitive function than their married counterparts, and the extent to which these associations vary across settings. We theorize that the practices around marriage in each setting, as well as the social stigma attached to marital dissolution, will reveal differing associations between marital status and cognition.

Corrigendum: Apolipoprotein E Genetic Variation and its Association With Cognitive Function in Rural-Dwelling Older South Africans.

[This corrects the article DOI: 10.3389/fgene.2021.

Apolipoprotein E Genetic Variation and Its Association With Cognitive Function in Rural-Dwelling Older South Africans.

Apolipoprotein E () 𝜀4 allele carrier status is well known for its association with an increased likelihood of developing Alzheimer's disease, but its independent role in cognitive function is unclear. genetic variation is understudied in African populations; hence, this cross-sectional study in a rural South African community examined allele and genotype frequencies, and their associations with cognitive function. Cognitive function was assessed using two different screening methods to produce a total cognition score and four domain-specific cognition scores for verbal episodic memory, executive function, language, and visuospatial ability.

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

Background: The 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.

Methods: Data 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).

Do You See What Eye See? Measurement, Correlates, and Functional Associations of Objective and Self-Reported Vision Impairment in Aging South Africans.

Our study investigates measurement, correlates, and functional associations of vision impairment (VI) in an aging population in rural South Africa. 1582 participants aged 40-69 reported on near (NVI) and distance vision impairment (DVI) and completed objective vision tests. Logistic and linear regression were used to evaluate sociodemographic, health, and psychosocial correlates of VI and assess relationships between VI and cognitive and physical function.

Grandchild Caregiving and Cognitive Health Among Grandparents in Rural South Africa.

We investigate how caregiving for grandchildren is associated with cognitive function among rural South Africans, and whether the association differs by gender. We further investigate whether measures of physical activity or social engagement mediate this association. Data were from interviews with 3668 Black, South African grandparents in the "Health and Aging in Africa: A Longitudinal Study of an INDEPTH Community in South Africa" study, conducted between 2014 and 2015.

Incidence of Cognitive Impairment during Aging in Rural South Africa: Evidence from HAALSI, 2014 to 2019.

Introduction: Despite rapid population aging, there are currently limited data on the incidence of aging-related cognitive impairment in sub-Saharan Africa. We aimed to determine the incidence of cognitive impairment and its distribution across key demographic, social, and health-related factors among older adults in rural South Africa.

Methods: Data were from in-person interviews with 3,856 adults aged ≥40 who were free from cognitive impairment at baseline in the population-representative cohort, "Health and Aging in Africa: a Longitudinal Study of an INDEPTH Community in South Africa" (HAALSI), in Agincourt sub-district, Mpumalanga province, South Africa (2014-19).

Social contact, social support, and cognitive health in a population-based study of middle-aged and older men and women in rural South Africa.

Background: Several theories seek to explain how social connections and cognitive function are interconnected in older age. These include that social interaction protects against cognitive decline, that cognitive decline leads to shedding of social connections and that cognitive decline leads to increased instrumental support. We investigated how patterns of social contact, social support and cognitive health in rural South Africa fit with these three theories.

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

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.

Ascertaining Subjective Cognitive Decline: A Comparison of Approaches and Evidence for Using an Age-Anchored Reference Group.

Background: Subjective cognitive decline (SCD) is increasingly considered promising to detect preclinical Alzheimer's disease. How SCD is ascertained is critical for determining its potential utility in identifying at-risk individuals, yet SCD measures differ along several dimensions.

Objective: We aimed to examine the extent to which reports of SCD in healthy elderly may be influenced by the characteristics of the SCD measures.

Subjective word-finding difficulty reduces engagement in social leisure activities in Alzheimer's disease.

Objectives: To assess the influence of subjective word-finding difficulty on degree of engagement in social leisure activities among individuals with Alzheimer's disease (AD).

Design: Analysis of data collected from the second cohort of the Multicenter Study of Predictors of Disease Course in Alzheimer's disease.

Setting: Four study sites in the United States and France.

Bilingualism does not alter cognitive decline or dementia risk among Spanish-speaking immigrants.

Objective: Clinic-based studies suggest that dementia is diagnosed at older ages in bilinguals compared with monolinguals. The current study sought to test this hypothesis in a large, prospective, community-based study of initially nondemented Hispanic immigrants living in a Spanish-speaking enclave of northern Manhattan.

Method: Participants included 1,067 participants in the Washington/Hamilton Heights Inwood Columbia Aging Project (WHICAP) who were tested in Spanish and followed at 18-24 month intervals for up to 23 years.

Picture-word interference reveals inhibitory effects of syllable frequency on lexical selection.

While previous research has shown that high syllable frequency can facilitate speech production at the level of phonological/phonetic encoding, little is known about its influence on prephonological processes, specifically lexical selection. The current study used a picture-word interference (PWI) task to (a) shed light on the stages of lexical access where syllable frequency is relevant, and (b) inform as to whether lexical selection is accomplished via competition among activated word options. Participants named pictures whose names had high-frequency (HF) and low-frequency (LF) first syllables while ignoring phonologically related (same first syllable) or unrelated distractor words that were presented simultaneously.

Tip-of-the-tongue states reveal age differences in the syllable frequency effect.

Syllable frequency has been shown to facilitate production in some languages but has yielded inconsistent results in English and has never been examined in older adults. Tip-of-the-tongue (TOT) states represent a unique type of production failure where the phonology of a word is unable to be retrieved, suggesting that the frequency of phonological forms, like syllables, may influence the occurrence of TOT states. In the current study, we investigated the role of first-syllable frequency on TOT incidence and resolution in young (18-26 years of age), young-old (60-74 years of age), and old-old (75-89 years of age) adults.

Older adults' detection of misspellings during reading.

Objectives: Previous research has suggested that older adults' ability to detect a word as correctly or incorrectly spelled is intact, relative to younger adults. The purpose of the present experiment was to investigate the stability of misspelling detection processes across older adulthood when misspellings are presented in the context of reading.

Methods: Participants included 180 older adults represented equally from three decades: young-old adults in their 60s, middle-old adults in their 70s, and old-old adults in their 80s.