Browsing by Author "Stephen M Tollman"

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    Carotid Atherosclerosis, Microalbuminuria, and Estimated 10-Year Atherosclerotic Cardiovascular Disease Risk in Sub-Saharan Africa
    (2022-04-01) Engelbert A Nonterah; Daniel Boateng; Nigel J Crowther; Kerstin Klipstein-Grobusch; Abraham R Oduro; Godfred Agongo; Shukri F Mohamed; Palwendé R Boua; Solomon S R Choma; Shane A Norris; Stephen M Tollman; Michiel L Bots; Michèle Ramsay; Diederick Grobbee
    Importance: Carotid atherosclerosis and microalbuminuria are associated with atherosclerotic cardiovascular disease (ASCVD) but are understudied in sub-Saharan Africa. Objective: To evaluate the association of carotid atherosclerosis and microalbuminuria with 10-year ASCVD risk in middle-aged sub-Saharan African individuals. Design, setting, and participants: This cross-sectional study conducted analyses of baseline data from the African-Wits-INDEPTH (International Network for the Demographic Evaluation of Populations and Their Health in Low- and Middle-Income Countries) genomic study (AWI-Gen). Women and men aged 40 to 60 years without baseline CVD and drawn from Burkina Faso, Ghana, Kenya, and South Africa were included. Main outcomes and measures: Hypotheses for the analyses were formulated after data collection. The main exposures were carotid atherosclerosis, assessed using carotid intima-media thickness (CIMT) using B-mode ultrasonography, and microalbuminuria, measured using spot urine albumin (SUA) and urine albumin-creatinine ratio (uACR). The main outcome was high ASCVD risk, defined as a 2018 Pooled Cohort Equations score of 7.5% or greater. Associations were estimated using adjusted multivariable logistic regression analyses. Findings: A total of 9010 participants with a mean (SD) age of 50 (6) years and 4533 (50.3%) women were included. High CIMT, SUA, and uACR were each associated with older age (eg, mean [SD] age of participants with high vs reference range CIMT: 55 [5] years vs 50 [6] years; P < .001) and high prevalence of both diabetes and hypertension (eg, hypertension among those with high vs reference range SUA: 213 of 1117 [19.1%] vs 356 of 2549 [14.0%]; P < .001). Smokers were likely to have higher vs reference range SUA (210 [18.8%] vs 407 [16.0%]) and uACR (138 of 707 [19.5%] vs 456 of 2797 [16.3%]). Carotid atherosclerosis was common in Burkina Faso (82 of 262 [31.3%]) and Ghana (91 [34.7%]), while microalbuminuria, measured by SUA, was common in Kenya (272 [24.4%]) and South Africa (519 [46.5%]). SUA was associated with higher odds of carotid atherosclerosis (odds ratio [OR], 1.77; 95% CI, 1.04-3.01) compared with uACR (OR, 0.51; 95% CI, 0.27-0.95). Common CIMT, SUA, and uACR were associated with 10-year ASCVD risk, with CIMT having a stronger association with 10-year ASCVD risk in both women (OR, 1.95; 95% CI, 1.78-2.14) and men (OR, 1.73; 95% CI, 1.55-1.93) than SUA (women: OR, 1.29; 95% CI, 1.12-1.43; men: OR, 1.46; 95% CI, 1.26-1.55) and uACR (women: OR, 1.32; 95% CI, 1.10-1.54; men: OR, 1.35; 95% CI, 1.15-1.46). Conclusions and relevance: The presence of microalbuminuria measured by SUA may indicate risk of subclinical carotid atherosclerosis and high 10-year ASCVD risk in middle-aged residents of sub-Saharan Africa. These data should be confirmed in longitudinal studies of cardiovascular events.
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    Cohort Profile: Health and Ageing in Africa: A Longitudinal Study of an INDEPTH Community in South Africa (HAALSI).
    (2018) F Xavier Go´ mez-Olive´; Livia Montana; Ryan G Wagner; Chodziwadziwa W Kabudula; Julia K Rohr; Kathleen Kahn; Till Ba¨rnighausen; Mark Collinson; David Canning; Thomas Gaziano; Joshua A Salomon; Collin F Payne; Alisha Wad; Stephen M Tollman; Lisa Berkman
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    Estimating the Prevalence of over- and Under-Reporting in HIV Testing, Status and Treatment in Rural Northeast South Africa: A Comparison of a Survey and Clinic Records
    (2023-10-27) Hannah H Leslie; Chodziwadziwa W Kabudula; Rebecca L West; Mi-Suk Kang Dufour; Aimée Julien; Nkosinathi G Masilela; Stephen M Tollman; Audrey Pettifor; Kathleen Kahn; Sheri A Lippman
    We assess the accuracy of self-reported testing, HIV status, and treatment responses compared to clinical records in Ehlanzeni District, South Africa. We linked a 2018 population-based survey of adults 18-49 years old with clinical data at local primary healthcare facilities from 2014 to 2018. We calculated self-reported testing, HIV status, and treatment, and triangulated findings with clinic record data. We adjusted testing estimates for known gaps in HIV test documentation. Of 2089 survey participants, 1657 used a study facility and were eligible for analysis. Half of men and 84% of women reported an HIV test in the past year. One third of reported tests could be confirmed in clinic data within 1 year and an additional 13% within 2 years; these fractions increased to 57% and 22% respectively limiting to participants with a verified clinic file. After accounting for gaps in clinic documentation, we found that prevalence of recent HIV testing was closer to 15% among men and 51% in women. Estimated prevalence of known HIV was 16.2% based on self-report vs. 27.6% with clinic documentation. Relative to clinical records among confirmed clinic users, self report of HIV testing and of current treatment were highly sensitive but non-specific (sensitivity 95.5% and 98.8%, specificity 24.2% and 16.1% respectively), while self report of HIV status was highly specific but not sensitive (sensitivity 53.0%, specificity 99.3%). While clinical records are imperfect, survey-based measures should be interpreted with caution in this rural South African setting.
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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.