Cognition, Health, and Well-Being in a Rural Sub-Saharan African Population

Impact of Optimism on Cognitive Performance of People Living in Rural Area: Findings From a 20-Year Study in US Adults

Objectives: Mid- or early-late-life cognitive function is an indicator for developing late-life dementia. However, it is still unclear whether rural/urban living contexts provide cognitive benefits across adulthood. Further, higher optimism serves as a general protective factor for many health outcomes. The present study examines associations between rurality/urbanicity, optimism, and change in mid/late-life cognitive functions over time. Methods: Data were from waves 1 to 3 (1995-2015) of the Midlife in the United States (MIDUS) study (N = 2,507). Structural equation models examine whether long-term rural living across both waves (1-2) or intermittent rural living at one wave is associated with better cognitive function over 20 years, compared to no rural living, while controlling for prior cognitive function and covariates (baseline socio-demographics, health, and functional status). Additionally, we assessed if optimism mediates the above associations. Results: After controlling for covariates, long-term rural living (waves 1-2) was indirectly (through less optimism) associated with significantly lower levels of cognitive executive function and episodic memory in wave 3. Conclusions: While long-term rural living and cognitive outcomes have no direct association for MIDUS middle-aged and older adults, mediating roles of optimism in these associations were evident. Future investigations could examine mechanisms that underlie these risk/protective factors on late-life cognition.

Cognitive Impairment and the Associated Factors Among Older People in Rural Central Tanzania

AIM

This study examined the profile of cognitive impairment and associated factors among older people in rural central Tanzania.

METHODS

We conducted a cross-sectional study involving 462 community-dwelling older adults. We performed cognitive, psychosocial, and clinical assessments and face-to-face interviews with all older adults. Descriptive, bivariate and multivariate linear regression analyses were performed to determine the participant's cognitive performance and the associated factors.

RESULTS

The mean cognitive score on the Identification and Intervention for Dementia in Elderly Africans cognitive test was 11.04 (SD=2.89). Per the proposed cut-off scores to define probable and possible dementia, 13.2% of the population had probable dementia and another 13.9% had possible dementia. Increase in age was associated with poor cognitive performance (β=-0.076, 95% CI=-0.109 to -0.043, P<0.001); whereas male sex (β=0.989, 95% CI=0.333 to 1.645, P=0.003), higher educational attainment (β=2.575, 95% CI=0.557 to 4.594, P=0.013) and performance in instrumental activities of daily living (β=0.552, 95% CI=0.376 to 0.729, P<0.001) were associated with higher cognitive performance.

DISCUSSION

Older people in rural settings of central Tanzania have poor cognitive functions and are at high risk of further cognitive decline. Preventive and therapeutic programs for the affected older people are warranted to prevent further decline and maintain quality of life.

The path between socioeconomic inequality and cognitive function: A mediation analysis based on the HAALSI cohort in rural South Africa

Background

Socioeconomic position (SEP) strongly predicts late-life cognitive health, yet the pathways between SEP and cognitive function remain unclear. This study assessed whether and to what extent the association between SEP and cognitive function in the adult population in rural South Africa is mediated by some health conditions, behavioral factors, and social capital factors.

Methods

In this cross-sectional study, we used data from the 2014–15 “Health and Aging Africa: A Longitudinal Study of an INDEPTH Community in South Africa” (HAALSI) cohort, including 5,059 adults aged 40+ years from the Agincourt sub-district in Mpumalanga Province, South Africa. SEP, the independent variable, was measured based on ownership of household goods. Cognitive function, the dependent variable, was assessed using questions related to time orientation and immediate and delayed word recall. We used the multiple-mediation analysis on 4125 individuals with complete values on all variables to assess the mediating roles of health conditions (hypertension, diabetes, obesity, and disability), behavioral factors (leisure physical activity, alcohol consumption, and tobacco smoking), and social capital factors (community's willingness to help, trust, sense of safety, and social network contact) in the association between SEP and cognitive function.

Results

Compared to adults in the poorest wealth quintile, those in the richest wealth quintile had better cognition (β = 0.903, p &lt; 0.001). The mediation analysis revealed that health conditions mediated 20.7% of the total effect of SEP on cognitive function. In comparison, 3.3% was mediated by behavioral factors and only 0.7% by social capital factors. In the multiple-mediator model, 17.9% of the effect of SEP on cognitive function was jointly mediated by health conditions, behavioral factors, and social capital factors.

Conclusion

Low socioeconomic position is a significant factor associated with poor cognitive function among adults aged 40 years and above in South Africa. Health conditions mainly mediate the effects between SEP and cognitive function. Therefore, actions to prevent and control chronic health conditions can serve as the entry point for intervention to prevent poor cognitive function among people with low socioeconomic status.

Cognition and Cognitive Changes in a Low-Income Sub-Saharan African Aging Population

BACKGROUND

Cognition and its age-related changes remain vastly understudied in low-income countries (LICs), despite evidence suggesting that cognitive decline among aging low-income populations is a rapidly increasing disease burden often occurring at younger ages as compared to high-income countries (HICs).

OBJECTIVE

We examine patterns of cognition among men and women, 45 + years old, living in rural Malawi. We analyze how key socioeconomic characteristics predict levels of cognition and its changes as individuals get older.

METHODS

Utilizing the Mature Adults Cohort of the Malawi Longitudinal Study of Families and Health (MLSFH-MAC) collected during 2012-2017, we estimate standard regression models to analyze predictors of the age- and sex-specific levels and longitudinal changes in cognition. Cognition is assessed with a screening instrument that is adapted to this low-literacy context and measures different domains such as language, attention, or executive functioning.

RESULTS

Women have lower levels of cognition than men, a pattern in stark contrast to findings in HICs. Schooling and socioeconomic status increase the probability of having consistently high performance during the cognitive assessment. Cognitive decline accelerates with age and is detectable already at mid-adult ages (45-55 years). Despite lower levels of cognitive function observed among women, the pace of decline with age is similar for both genders.

CONCLUSION

Women are particularly affected by poor cognition in this context. The study emphasizes the importance of prioritizing cognitive health and research on cognition among older individuals in sub-Saharan Africa LICs, to which relatively little health care resources continue to be allocated.

The Association of Reproductive Aging with Cognitive Function in Sub-Saharan African Women

Life expectancy in sub-Saharan African women is increasing, and by the late 2020s an estimated 76% of postmenopausal women globally will be living in developing countries. Menopause transition has been associated with cognitive decline in a wide range of studies, but data on cognition and reproductive aging are lacking in sub-Saharan African women. Approximately 72 million people in the region are expected to suffer from dementias and neurocognitive decline by 2050. Studies show that compromised cognitive health in low-income countries has significant implications for adult quality of life and socioeconomic development. There is now an urgent need to further examine risk factors for cognitive decline in these aging women and to understand the ability of public health programs to diagnose and treat cognitive dysfunction. This review examines studies assessing cognition and aging in sub-Saharan African adults, while addressing the significant research gaps. It examines data on the association of the menopause transition with cognitive function and describes how validated tools should be available to assess both menopausal stage and symptoms. Culturally appropriate and validated neurocognitive measures are required to better understand the relationship of reproductive aging with cognition. Longitudinal population-based studies are needed to assess the effect of lifestyle interventions, such as diet and exercise, on cognitive health in sub-Saharan African populations, with an emphasis on women as they transition into menopause.

Cohort profile: the mature adults cohort of the Malawi longitudinal study of families and health (MLSFH-MAC)

PURPOSE

The Mature Adults Cohort of the Malawi Longitudinal Study of Families and Health (MLSFH-MAC) contributes to global ageing studies by providing a rare opportunity to study the processes of individual and population ageing, the public health and social challenges associated with ageing and the coincident shifts in disease burdens, in a low-income, high HIV prevalence, sub-Saharan African (SSA) context.

PARTICIPANTS

The MLSFH-MAC is an open population-based cohort study of mature adults aged 45+ years living in rural communities in three districts in Malawi. Enrolment at baseline is 1266 individuals in 2012. Follow-ups were in 2013, 2017 and 2018 when the cohort size reached 1626 participants in 2018.

FINDINGS TO DATE

Survey instruments cover ageing-related topics such as cognitive and mental health, non-communicable diseases (NCDs) and related health literacy, subjective survival expectations, measured biomarkers including HIV, grip strength, hypertension, fasting glucose, body mass index (BMI), broad individual-level and household-level social and economic information, a 2018 qualitative survey of mature adults and community officials, 2019 surveys of village heads, healthcare facilities and healthcare providers in the MLSFH-MAC study areas. Across many domains, MLSFH-MAC allows for comparative research with global ageing studies through harmonised measures and instruments. Key findings to date include a high prevalence of depression and anxiety among older adults, evidence for rapid declines in cognitive health with age, a low incidence of HIV among mature adults, rising prevalence of HIV due to increased survival of HIV-positive individuals and poor physical health with high NCD prevalence.

FUTURE PLANS

An additional wave of MLSFH-MAC is forthcoming in 2021, and future expansions of the cohort are planned. MLSFH-MAC data will also be publicly released and will provide a wealth of information unprecedented for ageing studies in a low-income SSA context that broadly represents the socioeconomic environment of millions of individuals in south-eastern Africa.

Cognitive and Educational Interventions for Orphans and Vulnerable Children Affected by HIV/AIDS: A Meta-Analysis

Orphans and vulnerable children affected by HIV/AIDS (HIV OVC) are at risk for cognitive difficulties and lack of access to education. Interventions addressing cognitive or educational outcomes for HIV OVC worldwide were examined through systematic searches conducted from October 2016 to 2019. We examined the summative effectiveness of interventions and the specific effects of participant age and intervention length. Interventions targeting cognitive outcomes had a small, significant effect, with no effect of moderating variables. Interventions targeting educational outcomes had significant effects. Educational interventions over 1 year were effective, but effects of intervention length were not significant. Overall, this review provides support for the effectiveness of interventions targeting cognitive and educational outcomes for OVC and highlights the need for more research on such interventions.