Publications

2019
Carlos Riumallo-Herl, David Canning, and Chodziwadziwa Kabudula. 2019. “Health inequalities in the South African elderly: The importance of the measure of social-economic status.” The Journal of the Economics of Ageing. Publisher's VersionAbstract
A common approach when studying inequalities in health is to use a wealth index based on household durable goods as a proxy for socio-economic status. We test this approach for elderly health using data from an aging survey in a rural area of South Africa and find much steeper gradients for health with consumption adjusted for household size than with the wealth index. These results highlight the importance of the measure of socioeconomic status used when measuring health gradients, and the need for direct measures of household consumption or income in ageing studies.
Lindsay C Kobayashi, Farrah J Mateen, Livia Montana, Ryan G Wagner, Kathleen Kahn, Stephen M Tollman, and Lisa F Berkman. 2019. “Cognitive Function and Impairment in Older, Rural South African Adults: Evidence from "Health and Aging in Africa: A Longitudinal Study of an INDEPTH Community in Rural South Africa".” Neuroepidemiology, 52, 1-2, Pp. 32-40. Publisher's VersionAbstract
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.
Guy Harling, Collin F. Payne, Justine I. Davies, F. Xavier Gomez-Olive, Kathleen Kahn, Lenore Manderson, Farrah J. Mateen, Stephen M. Tollman, and Miles D. Witham. 2019. “Impairment in Activities of Daily Living, Care Receipt, and Unmet Needs in a Middle-Aged and Older Rural South African Population: Findings From the HAALSI Study.” Journal of Aging and Health, Pp. 0898264318821220. Publisher's VersionAbstract
Objectives: The objective of this study is to analyze the degree to which care needs are met in an aging rural African population. Method: Using data from the Health and Aging in Africa: Longitudinal Study of an INDEPTH Community (HAALSI) baseline survey, which interviewed 5,059 adults aged older than 40 years in rural South Africa, we assessed the levels of limitations in activities of daily living (ADLs) and in unmet care for these ADLs, and evaluated their association with sociodemographic and health characteristics. Results: ADL impairment was reported by 12.2% of respondents, with the proportion increasing with age. Among those with ADL impairment, 23.9% reported an unmet need and 51.4% more a partially met need. Relatives provided help most often; formal care provision was rare. Unmet needs were more frequent among younger people and women, and were associated with physical and cognitive deficits, but not income or household size. Discussion: Unmet care needs in rural South Africa are often found among individuals less expected to require care.
Angela Y Chang, FX Gómez-Olivé, Jennifer Manne-Goehler, Alisha N Wade, Stephen M Tollman, Thomas A Gaziano, and Joshua A. Salomon. 2019. “Multimorbidity and care for hypertension, diabetes and HIV among older adults in rural South Africa.” Bulletin of the World Health Organization, 97, 1, Pp. 10-23. Publisher's VersionAbstract
Objective To examine how multimorbidity might affect progression along the continuum of care among older adults with hypertension, diabetes and human immunodeficiency virus (HIV) infection in rural South Africa.
Methods We analysed data from 4447 people aged 40 years or older who were enrolled in a longitudinal study in Agincourt sub-district. Household-based interviews were completed between November 2014 and November 2015. For hypertension and diabetes (2813 and 512 people, respectively), we defined concordant conditions as other cardiometabolic conditions, and discordant conditions as mental disorders or HIV infection. For HIV infection (1027 people) we defined any other conditions as discordant. Regression models were fitted to assess the relationship between the type of multimorbidity and progression along the care continuum and the likelihood of patients being in each stage of care for the index condition (four stages from testing to treatment).
Findings People with hypertension or diabetes plus other cardiometabolic conditions were more like to progress through the care continuum for the index condition than those without cardiometabolic conditions (relative risk, RR: 1.14, 95% confidence interval, CI: 1.09–1.20, and RR: 2.18, 95% CI: 1.52–3.26, respectively). Having discordant comorbidity was associated with greater progression in care for those with hypertension but not diabetes. Those with HIV infection plus cardiometabolic conditions had less progress in the stages of care compared with those without such conditions (RR: 0.86, 95% CI: 0.80–0.92).
Conclusion Patients with concordant conditions were more likely to progress further along the care continuum, while those with discordant multimorbidity tended not to progress beyond diagnosis. 
2018
Elyse A. Jennings, Nolwazi Mkhwanazi, and Lisa Berkman. 12/6/2018. “Receipt of emotional support among rural South African adults.” Ageing and Society, Pp. 1–25. Publisher's Version
Gómez-Olivé FX, Julia K Rohr, Laura C Roden, Dale E Rae, and Malcolm von Schantz. 11/23/2018. “Associations between sleep parameters, non-communicable diseases, HIV status and medications in older, rural South Africans.” Scientific Reports, 8, 1. Publisher's VersionAbstract
As part of the Health and Aging in Africa: A Longitudinal Study of an INDEPTH Community in South Africa (HAALSI), we investigated sleep habits and their interactions with HIV or non-communicable diseases (NCDs) in 5059 participants (median age: 61, interquartile range: 52—71, 54% females). Self-reported sleep duration was 8.2 ± 1.6h, and bed and rise times were 20:48 ± 1:15 and 05:31 ± 1:05 respectively. Ratings of insufficient sleep were associated with older age, lack of formal education, unemployment, and obesity (p < 0.05). Ratings of restless sleep were associated with being older, female, having more education, being unemployed, and single. Hypertension was associated with shorter self-reported sleep duration, poor sleep quality, restless sleep, and periods of stopping breathing during the night (p < 0.05). HIV positive individuals not on antiretroviral treatment (ART) reported more nocturnal awakenings than those on ART (p = 0.029) and HIV negative individuals (p = 0.024), suggesting a negative net effect of untreated infection, but not of ART, on sleep quality. In this cohort, shorter, poor-quality sleep was associated with hypertension, but average self-reported sleep duration was longer than reported in other regions globally. It remains to be determined whether this is particular to this cohort, South Africa in general, or low- to middle-income countries undergoing transition.
Thiago Veiga Jardim, Miles D. Witham, Shafika Abrahams-Gessel, F. Xavier Gómez-Olivé, Stephen Tollman, Lisa Berkman, and Thomas A. Gaziano. 10/12/2018. “Cardiovascular Disease Profile of the Oldest Adults in Rural South Africa: Data from the HAALSI Study (Health and Aging in Africa: Longitudinal Studies of INDEPTH Communities).” Journal of the American Geriatrics Society. Publisher's VersionAbstract
{Objectives To characterize the cardiovascular disease (CVD) profile of individuals aged 80 and older in rural South Africa. Design First wave of population-based longitudinal cohort. Setting Agincourt subdistrict (Mpumalanga Province) in rural South Africa. Participants Adults residents (N = 5,059). Measurements In-person interviews were conducted to obtain social, behavioral, economic, and clinical data. Prevalence of hypertension, diabetes, dyslipidemia, high waist-to-hip ratio, overweight and obesity, high-risk high-sensitivity C-reactive protein, smoking, stroke, myocardial infarction, angina pectoris, and heart failure in individuals younger than 65, aged 65 to 79, and aged 80 and older were compared. Associations between self-reported treatments and determinants of hypertension treatment in those aged 80 and older were assessed using multivariable regression. Results Of 5,059 individuals included, 549 (10.8%) were aged 80 and older, and their CVD prevalence was 17.9% (stroke 3.8%, myocardial infarction 0.5%, angina pectoris 13.5%, heart failure 0.7%). Hypertension prevalence in this group was 73.8%, and along with angina pectoris, it increased with age (p<.001), whereas overweight and obesity (46.4%), dyslipidemia (39.1%), and smoking prevalences (3.1%) decreased (p<.001). Hypertension treatment was significantly associated with being aged 80 and older (odds ratio (OR)=1.48; 95% confidence interval (CI)=1.14–1.92
Guy Harling, Katherine Ann Morris, Lenore Manderson, Jessica M Perkins, and Lisa F Berkman. 2018. “Age and Gender Differences in Social Network Composition and Social Support Among Older Rural South Africans: Findings From the HAALSI Study.” The Journals of Gerontology: Series B, Pp. gby013. Publisher's Version
Molly S. Rosenberg, Francesc X. Gómez-Olivé, Julia K. Rohr, Kathleen Kahn, and Till W. Bärnighausen. 2018. “Are circumcised men safer sex partners? Findings from the HAALSI cohort in rural South Africa.” PLOS ONE, 13, 8, Pp. 1-10. Publisher's VersionAbstract
Introduction The real-world association between male circumcision and HIV status has important implications for policy and intervention practice. For instance, women may assume that circumcised men are safer sex partners than non-circumcised men and adjust sexual partnering and behavior according to these beliefs. Voluntary medical male circumcision (VMMC) is highly efficacious in preventing HIV acquisition in men and this biological efficacy should lead to a negative association between circumcision and HIV. However, behavioral factors such as differential selection into circumcision based on current HIV status or factors associated with future HIV status could reverse the association. Here, we examine how HIV prevalence differs by circumcision status in older adult men in a rural South African community, a non-experimental setting in a time of expanding VMMC access. Methods We analyzed data collected from a population-based sample of 2345 men aged 40 years and older in a rural community served by the Agincourt Health and socio-Demographic Surveillance System site in Mpumalanga province, South Africa. We describe circumcision prevalence and estimate the association between circumcision and laboratory-confirmed HIV status with log-binomial regression models. Results One quarter of older men reported circumcision, with slightly more initiation-based circumcisions (56%) than hospital-based circumcisions (44%). Overall, the evidence did not suggest differences in HIV prevalence between circumcised and uncircumcised men; however, those who reported hospital-based circumcision were more likely to test HIV-positive [PR (95% CI): 1.28 (1.03, 1.59)] while those who reported initiation-based circumcision were less likely to test HIV-positive [PR (95% CI): 0.68 (0.51, 0.90)]. Effects were attenuated, but not reversed after adjustment for key covariates. Conclusions Medically circumcised older men in a rural South African community had higher HIV prevalence than uncircumcised men, suggesting that the effect of selection into circumcision may be stronger than the biological efficacy of circumcision in preventing HIV acquisition. The impression given from circumcision policy and dissemination of prior trial findings that those who are circumcised are safer sex partners may be incorrect in this age group and needs to be countered by interventions, such as educational campaigns.
Jennifer Manne-Goehler, Julia Rohr, Livia Montana, Mark Siedner, Guy Harling, F. Xavier Gómez-Olivé, Pascal Geldsetzer, Ryan Wagner, Lubbe Wiesner, Kathleen Kahn, Stephen Tollman, and Till W. Bärnighausen. 2018. “ART Denial: Results of a Home-Based Study to Validate Self-reported Antiretroviral Use in Rural South Africa.” AIDS and Behavior. Publisher's VersionAbstract
There is increasing interest in home based testing and treatment of HIV to expand access to treatment in sub-Saharan Africa. Such programs rely on self-reported HIV history and use of antiretroviral therapy (ART). However, the accuracy of self-reported ART use in community settings is not well described. In this study, we compared self-reported ART (SR-ART) use in a home based survey against biological exposure to ART (BE-ART), in a population study of older adults in South Africa. Health and Aging in Africa: a Longitudinal Study of an INDEPTH community in South Africa (HAALSI) is a cohort of adults aged 40þinspace}+. The baseline home-based interview included self-reported HIV status and ART use. All participants also underwent biological testing for HIV antibodies, viral load and exposure to emtricitabine (FTC) or lamivudine (3TC), which are included in all first-line and second-line ART regimens in the public-sector South African HIV program. We calculated the performance characteristics for SR-ART compared to BE-ART and fit multivariable logistic regression models to identify correlates of invalid SR-ART responses. Of 4560 HAALSI participants with a valid HIV test result available, 1048 (23%) were HIV-positive and 734 [70% of people living with HIV (PLWH)] were biologically validated ART users (BE-ART). The sensitivity of SR-ART use was 64% (95% CI 61–68%) and the specificity was 94% (95% CI 91–96%); the positive predictive value (PPV) was 96% (95% CI 94–98%) and negative predictive value (NPV) was 52% (95% CI 48–56%). We found no sociodemographic predictors of accurate SR-ART use. Over one in three individuals with detectable ART in their blood denied current ART use during a home-based interview. These results demonstrate ongoing stigma related to HIV and its treatment, and have important implications for community health worker programs, clinical programs, and research studies planning community-based ART initiation in the region.
Xavier F Gómez-Olivé, Livia Montana, Ryan G Wagner, Chodziwadziwa W Kabudula, Julia K Rohr, Kathleen Kahn, Till Bärnighausen, Mark Collinson, David Canning, Thomas Gaziano, Joshua A Salomon, Collin F Payne, Alisha Wade, Stephen M Tollman, and Lisa Berkman. 2018. “Cohort Profile: Health and Ageing in Africa: A Longitudinal Study of an INDEPTH Community in South Africa (HAALSI).” International Journal of Epidemiology, 47, 3, Pp. 689-690j. Publisher's Version
Pascal Geldsetzer, Maria Vaikath, Ryan Wagner, Julia K Rohr, Livia Montana, Francesc X Gómez-Olivé, Molly S Rosenberg, Jennifer Manne-Goehler, Farrah J Mateen, Collin F Payne, Kathleen Kahn, Stephen M Tollman, Joshua A Salomon, Thomas A Gaziano, Till Bärnighausen, and Lisa F Berkman. 2018. “Depressive Symptoms and their Relation to Age and Chronic diseases among middle-aged and Older Adults in rural South Africa.” The Journals of Gerontology: Series A, Pp. gly145. Publisher's Version
Lindsay C. Kobayashi, Lisa F. Berkman, Ryan G. Wagner, Kathleen Kahn, Stephen Tollman, and S. V. Subramanian. 2018. “Education modifies the relationship between height and cognitive function in a cross-sectional population-based study of older adults in Rural South Africa.” European Journal of Epidemiology. Publisher's VersionAbstract
We aimed to estimate the relationship between height (a measure of early-life cumulative net nutrition) and later-life cognitive function among older rural South African adults, and whether education modified this relationship. Data were from baseline in-person interviews with 5059 adultsþinspace}≥þinspace}40 years in the population-based ``Health and Aging in Africa: A Longitudinal Study of an INDEPTH Community in South Africa'' (HAALSI) study in Agincourt sub-district, South Africa, in 2015. Linear regression was used to estimate the relationship between height quintile and latent cognitive function z-score (representing episodic memory, time orientation, and numeracy), with adjustment for life course covariates and a height-by-education interaction. Mean (SD) height was 162.7 (8.9) cm. Nearly half the sample had no formal education (46%; 2307/5059). Mean age- and sex-adjusted cognitive z-scores increased from −þinspace}0.68 (95% CI: −þinspace}0.76 to −þinspace}0.61) in those with no education in the shortest height quintile to 0.62 (95% CI: 0.52–0.71) in those with at least 8 years of education in the tallest height quintile. There was a linear height disparity in cognitive z-scores for those with no formal education (adjusted $\beta$þinspace}=þinspace}0.10; 95% CI: 0.08–0.13 per height quintile), but no height disparity in cognitive z-scores in those with any level of education. Short stature is associated with poor cognitive function and may be a risk factor for cognitive impairment among older adults living in rural South Africa. The height disparity in cognitive function was negated for older adults who had any level of education.
Guy Harling, Jessica M. Perkins, Francesc Xavier Gómez-Olivé, Katherine Morris, Ryan G. Wagner, Livia Montana, Chodziwadziwa W. Kabudula, Till Bärnighausen, Kathleen Kahn, and Lisa Berkman. 2018. “Interviewer-driven Variability in Social Network Reporting: Results from Health and Aging in Africa: A Longitudinal Study of an INDEPTH Community (HAALSI) in South Africa.” Field Methods, 30, 2, Pp. 140-154. Publisher's VersionAbstract
Social network analysis depends on how social ties to others are elicited during interviews, a process easily affected by respondent and interviewer behaviors. We investigate how the number of self-reported important social contacts varied within a single data collection round. Our data come from Health and Aging in Africa: a Longitudinal Study of an INDEPTH community (HAALSI), a comprehensive population-based survey of individuals aged 40 years and older conducted over 13 months at the Agincourt health and demographic surveillance site in rural South Africa. As part of HAALSI, interviewers elicited detailed egocentric network data. The average number of contacts reported by the 5,059 respondents both varied significantly across interviewers and fell over time as the data collection progressed, even after adjusting for respondent, interviewer, and respondent–interviewer dyad characteristics. Contact numbers rose substantially after a targeted interviewer intervention. We conclude that checking (and adjusting) for interviewer effects, even within one data collection round, is critical to valid and reliable social network analysis.
Ami R. Moore, Victor Prybutok, Anh Ta, and Foster Amey. 2018. “Personal social networks and health among aging adults in Agincourt, South Africa: A multidimensional approach.” Social Networks, 55, Pp. 142 - 148. Publisher's VersionAbstract
Abstract Personal social networks (SN) affect health and wellbeing. This study used a multidimensional approach of \SN\ and social determinants of health (SDH) to examine the association between \SN\ and self-reported physical health among the aging population of Agincourt, South Africa. We analyzed the composition of personal \SN\ and used a multiple linear regression analysis to examine both network dimensions and \SDH\ that correlate with physical health. Results highlight the complexity and nuances of social relationships. A few recommendations were also made.
Lindsay C. Kobayashi, Sarah Frank, Carlos Riumallo-Herl, David Canning, and Lisa Berkman. 2018. “Socioeconomic gradients in chronic disease risk behaviors in a population-based study of older adults in rural South Africa.” International Journal of Public Health. Publisher's VersionAbstract
To investigate the associations between household wealth, household consumption, and chronic disease risk behaviors among older adults in rural South Africa.
Nikkil Sudharsanan and David Bloom. 2018. “The Demography of Aging in Low- and Middle-Income Countries: Chronological versus Functional Perspectives.” In Future Directions for the Demography of Aging: Proceedings of a Workshop, Chapter 11: Pp. 309-338. Washington, DC: The National Academies Press. Publisher's Version
2017
Collin F. Payne, Alisha Wade, Chodziwadziwa W. Kabudula, Justine I. Davies, Angela Y. Chang, F. Xavier Gomez-Olive, Kathleen Kahn, Lisa F. Berkman, Stephen M. Tollman, Joshua A. Salomon, and Miles D. Witham. 12/28/2017. “Prevalence and correlates of frailty in an older rural African population: findings from the HAALSI cohort study.” BMC Geriatrics, 17, 1, Pp. 293. Publisher's VersionAbstract
Frailty is a key predictor of death and dependency, yet little is known about frailty in sub-Saharan Africa despite rapid population ageing. We describe the prevalence and correlates of phenotypic frailty using data from the Health and Aging in Africa: Longitudinal Studies of an INDEPTH Community cohort.
LC Kobayashi, MM Glymour, K Kahn, Collin F Payne, RG Wagner, Livia Montana, F Mateen, Stephen Tollman, and Lisa F. Berkman. 10/2017. “Childhood deprivation and later-life cognitive function in a population-based study of older rural South Africans.” Social Science & Medicin, 190, Pp. 20-28. Publisher's VersionAbstract
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.
Jennifer Manne-Goehler, Livia Montana, Francesc Xavier Gómez-Olivé, Julia Rohr, Guy Harling, Ryan G. Wagner, Alisha Wade, Chodziwadziwa W. Kabudula, Pascal Geldsetzer, Kathleen Kahn, Stephen Tollman, Lisa F. Berkman, Till W. Bärnighausen, and Thomas A. Gaziano. 2017. “The ART Advantage: Health Care Utilization for Diabetes and Hypertension in Rural South Africa.” JAIDS Journal of Acquired Immune Deficiency Syndromes, 75, 5, Pp. 561-567. Publisher's VersionAbstract
Background: The prevalence of diabetes and hypertension has increased in HIV-positive populations, but there is limited understanding of the role that antiretroviral therapy (ART) programs play in the delivery of services for these conditions. The aim of this study is to assess the relationship between ART use and utilization of health care services for diabetes and hypertension.Methods: Health and Aging in Africa: A Longitudinal Study of an INDEPTH Community in South Africa is a cohort of 5059 adults. The baseline study collects biomarker-based data on HIV, ART, diabetes, and hypertension and self-reported data on health care utilization. We calculated differences in care utilization for diabetes and hypertension by HIV and ART status and used multivariable logistic regressions to estimate the relationship between ART use and utilization of services for these conditions, controlling for age, sex, body mass index, education, and household wealth quintile.

Pages