Browsing by Author "Lisa F Berkman"

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    Cohort Profile Update: Cognition and dementia in the Health and Aging in Africa Longitudinal Study of an INDEPTH community in South Africa (HAALSI dementia)
    (2022-08-10) Darina T Bassil; Meagan T Farrell; Ryan G Wagner; Adam M Brickman; M Maria Glymour; Kenneth M Langa; Jennifer J Manly; Joel Salinas; Brent Tipping; Stephen Tollman; Lisa F Berkman
    The Health and Aging in Africa Longitudinal Study of an INDEPTH Community in South Africa (HAALSI) is a harmonized sister study to the US Health and Retirement Study (HRS). Established in 2015, it includes 5059 individuals aged 40 and over, in a rural community in Agincourt, South Africa. • In light of the projected rise of dementia burden in sub-Saharan Africa, the HAALSI Dementia study was launched in 2019 to investigate the prevalence, incidence and risk factors of cognitive decline and dementia in South Africa. • The HAALSI Dementia sample includes 635 individuals, 50 years and older, of whom 99 also participated in an ancillary magnetic resonance imaging (MRI) sub-study. • The HAALSI Dementia study encompasses a comprehensive, culturally sensitive cognitive battery with multidomain psychometric scales, informant interviews and neurological evaluations, and has sufficient overlap with international Harmonized Cognitive Assessment Protocol (HCAP) and HRS studies to enable cross-calibration. • For new collaborative projects and data sharing, please contact Darina Bassil [dbassil@hsph.harvard.edu].
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    Subjective social position and cognitive function in a longitudinal cohort of older, rural South African adults, 2014–2019
    (2021-09-23) Lindsay C Kobayashi; Emily P Morris; Guy Harling; Meagan T Farrell; Mohammed U Kabeto; Ryan G Wagner; Lisa F Berkman
    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 (followup). 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. Results SSP 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). Conclusion Independent 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.
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    The double-edged role of accessed status on health and well-being among middle- and older-age adults in rural South Africa: The HAALSI study
    (2022-09) Shao-Tzu Yu; Brian Houle; Lenore Manderson; Elyse A Jennings; Stephen M Tollman; Lisa F Berkman; Guy Harling
    Background: Social capital theory conceptualizes accessed status (the socioeconomic status of social contacts) as interpersonal resources that generate positive health returns, while social cost theory suggests that accessed status can harm health due to the sociopsychological costs of generating and maintaining these relationships. Evidence for both hypotheses has been observed in higher-income countries, but not in more resource-constrained settings. We therefore investigated whether the dual functions of accessed status on health may be patterned by its interaction with network structure and functions among an older population in rural South Africa. Method: We used baseline survey data from the HAALSI study ("Health and Aging in Africa: a Longitudinal Study of an INDEPTH Community in South Africa") among 4,379 adults aged 40 and older. We examined the direct effect of accessed status (measured as network members' literacy), as well as its interaction with network size and instrumental support, on life satisfaction and self-rated health. Results: In models without interactions, accessed status was positively associated with life satisfaction but not self-rated health. Higher accessed status was positively associated with both outcomes for those with fewer personal contacts. Interaction effects were further patterned by gender, being most health-protective for women with a smaller network and most health-damaging for men with a larger network. Conclusions: Supporting social capital theory, we find that having higher accessed status is associated with better health and well-being for older adults in a setting with limited formal support resources. However, the explanatory power of both theories appears to depending on other key factors, such as gender and network size, highlighting the importance of contextualizing theories in practice.