Publications

Forthcoming
Harling G, JM Perkins, Gómez-Olivé FX, Morris KA, Wagner RG, Montana L, Kabudula C, Bärnighausen TW, Kahn K, and Lisa F Berkman. Forthcoming. “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 Method.
2018
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, Pp. dyx247. 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.
Sheridan Reiger, Thiago Veiga Jardim, Shafika Abrahams-Gessel, Nigel J. Crowther, Alisha Wade, F. Xavier Gomez-Olive, Joshua Salomon, Stephen Tollman, and Thomas A. Gaziano. 2017. “Awareness, treatment, and control of dyslipidemia in rural South Africa: The HAALSI (Health and Aging in Africa: A Longitudinal Study of an INDEPTH Community in South Africa) study.” PLOS ONE, 12, 10, Pp. 1-12. Publisher's VersionAbstract
Dyslipidemia is a primary driver for chronic cardiovascular conditions and there is no comprehensive literature about its management in South Africa. The objective of this study was to assess the prevalence, awareness, treatment, and control of dyslipidemia in rural South Africa and how they are impacted by different behaviors and non-modifiable factors. To fulfill this objective we recruited for this cohort study adults aged ≥40 years residing in the Agincourt sub-district of Mpumalanga Province. Data collection included socioeconomic and clinical data, anthropometric measures, blood pressure (BP), HIV-status, point-of-care glucose and lipid levels. Framingham CVD Risk Score was ascribed to patients based upon categories for 10 year cardiovascular risk of low (<3%), moderate (≥3% and <15%), high (≥15% and <30%), and very high (≥30%).LDL cholesterol control by risk category was defined according to South African Guidelines. Multivariable logistic regression models were built to identify factors that were significantly associated with dyslipidemia and awareness of dyslipidemia From 5,059 respondents a total of 4247 subjects (83.9%) had their cholesterol levels measured and were included in our analysis. Overall, 67.3% (2860) of these met criteria for dyslipidemia, only 30 (1.05%) were aware of their condition, and only 21 subjects (0.73%) were on treatment. The majority have abnormalities in triglycerides (59.3%). As cardiovascular risk increased the rates of lipid control according to LDL level dropped. Multivariate logistic regression analyses showed that being overweight was predictive of dyslipidemia (OR 1.76; 95%CI 1.51–2.05, p<0.001) and dyslipidemia awareness (OR 2.58; 95%CI 1.19–5.58; p = 0.017). In conclusion, the very low awareness and treatment of dyslipidemia in this cohort indicate a greater need for systematic screening and education within the population and demonstrate that there are multiple opportunities to allay this burden.
Thomas A Gaziano, Shafika Abrahams-Gessel, Xavier F Gomez-Olive, Alisha Wade, Nigel J Crowther, Sartaj Alam, Jennifer Manne-Goehler, Chodziwadziwa W Kabudula, Ryan Wagner, Julia Rohr, Livia Montana, Kathleen Kahn, Till W Bärnighausen, Lisa F Berkman, and Stephen Tollman. 2017. “Cardiometabolic risk in a population of older adults with multiple co-morbidities in rural south africa: the HAALSI (Health and Aging in Africa: longitudinal studies of INDEPTH communities) study.” BMC Public Health, 17, 1, Pp. 206.Abstract
BACKGROUND: A consequence of the widespread uptake of anti-retroviral therapy (ART) is that the older South African population will experience an increase in life expectancy, increasing their risk for cardiometabolic diseases (CMD), and its risk factors. The long-term interactions between HIV infection, treatment, and CMD remain to be elucidated in the African population. The HAALSI cohort was established to investigate the impact of these interactions on CMD morbidity and mortality among middle-aged and older adults. METHODS: We recruited randomly selected adults aged 40 or older residing in the rural Agincourt sub-district in Mpumalanga Province. In-person interviews were conducted to collect baseline household and socioeconomic data, self-reported health, anthropometric measures, blood pressure, high-sensitivity C-reactive protein (hsCRP), HbA1c, HIV-status, and point-of-care glucose and lipid levels. RESULTS: Five thousand fifty nine persons (46.4% male) were enrolled with a mean age of 61.7 ± 13.06 years. Waist-to-hip ratio was high for men and women (0.92 ± 0.08 vs. 0.89 ± 0.08), with 70% of women and 44% of men being overweight or obese. Blood pressure was similar for men and women with a combined hypertension prevalence of 58.4% and statistically significant increases were observed with increasing age. High total cholesterol prevalence in women was twice that observed for men (8.5 vs. 4.1%). The prevalence of self-reported CMD conditions was higher among women, except for myocardial infarction, and women had a statistically significantly higher prevalence of angina (10.82 vs. 6.97%) using Rose Criteria. The HIV(-) persons were significantly more likely to have hypertension, diabetes, or be overweight or obese than HIV(+) persons. Approximately 56% of the cohort had at least 2 measured or self-reported clinical co-morbidities, with HIV(+) persons having a consistently lower prevalence of co-morbidities compared to those without HIV. Absolute 10-year risk cardiovascular risk scores ranged from 7.7-9.7% for women and from 12.5-15.3% for men, depending on the risk score equations used. CONCLUSIONS: This cohort has high CMD risk based on both traditional risk factors and novel markers like hsCRP. Longitudinal follow-up of the cohort will allow us to determine the long-term impact of increased lifespan in a population with both high HIV infection and CMD risk.
Thiago Veiga Jardim, Sheridan Reiger, Shafika Abrahams-Gessel, Nigel J Crowther, Alisha Wade, Xavier F Gómez-Olivé, Joshua Salomon, Stephen Tollman, and Thomas A Gaziano. 2017. “Disparities in Management of Cardiovascular Disease in Rural South Africa: Data From the HAALSI Study (Health and Aging in Africa: Longitudinal Studies of International Network for the Demographic Evaluation of Populations and Their Health Communities).” Circ Cardiovasc Qual Outcomes, 10, 11.Abstract
BACKGROUND: Optimal secondary prevention is critical for the reduction of repeated cardiovascular events, and the control of cardiovascular risk factors in this context is essential. Data on secondary prevention of cardiovascular disease (CVD) in sub-Saharan Africa are needed to inform intervention strategies with a particular focus on local disparities. The aim of this study was to assess CVD management in a rural community in northeast South Africa. METHODS AND RESULTS: We recruited adults aged ≥40 years residing in the Agincourt subdistrict of Mpumalanga province. Data collection included socioeconomic and clinical data, anthropometric measures, blood pressure, human immunodeficiency virus status, and point-of-care glucose and lipid levels. CVD was defined as self-report of myocardial infarction and stroke or angina diagnosed by Rose Criteria. A linear regression model was built to identify variables independently associated with the number of cardiovascular risk factors controlled. Of 5059 subjects, 592 (11.7%) met CVD diagnostic criteria. Angina was reported in 77.0% of these subjects, stroke in 25.2%, and myocardial infarction in 3.7%. Percent controlled of the 5 individual risk factors assessed were as follows: tobacco 92.9%; blood pressure 51.2%; body mass index 33.8%; low-density lipoprotein 31.4%; and waist-to-hip ratio 29.7%. Only 4.4% had all 5 risk factors controlled and 42.4% had ≥3 risk factors controlled. Male sex (β coefficient=0.44; 95% confidence interval, 0.25-0.63; P<0.001), absence of physical disability (β coefficient=0.40; 95% confidence interval, 0.16-0.65; P=0.001), and socioeconomic status (β coefficient=0.10; 95% confidence interval, 0.01-0.19; P=0.035) were directly associated with the number of risk factors controlled. CONCLUSIONS: Currently, CVD is not being optimally managed in this rural area of South Africa. There are significant disparities in control of CVD risk factors by sex, socioeconomic status, and level of disability. Efforts to improve secondary prevention in this population should be focused on females, subjects from lower socioeconomic status, and those with physical disabilities.
Thiago Veiga Jardim, Sheridan Reiger, Shafika Abrahams-Gessel, Xavier F Gomez-Olive, Ryan G Wagner, Alisha Wade, Till W Bärnighausen, Joshua Salomon, Stephen Tollman, and Thomas A Gaziano. 2017. “Hypertension management in a population of older adults in rural South Africa.” J Hypertens, 35, 6, Pp. 1283-1289.Abstract
OBJECTIVE: Assess awareness, treatment, and control of hypertension, as an indication of its management, in rural South Africa, especially regarding modifiers of these variables. METHODS: A population-representative sample of adults aged at least 40 years residing in the rural Agincourt subdistrict (Mpumalanga Province) covered by a long-term health and sociodemographic surveillance system was recruited. In-person interviews, physical exams, and dried blood spots were collected. Hypertension awareness, treatment, and control rates were assessed. A regression model was built to identify predictors of those outcomes. RESULTS: The mean age of the 2884 hypertensive participants was 64.1 ± 12.7 years. Hypertension awareness rate was 64.4%, treatment among those aware was 89.3 and 45.8% of those treated were controlled. Considering aware and unaware hypertensives, treatment rate was 49.7% and control 22.8%. In the multivariable regression model, awareness was predicted by female sex, age at least 60 years, higher social economic status, prior cardiovascular disease (CVD), nonimmigrant status, literacy, and physical limitation. Improved control among those treated was predicted by age at least 60 years. Blood pressure control among all hypertensive study participants was predicted by female sex, being HIV-negative, age at least 60 years, nonimmigrant status, and prior CVD. CONCLUSION: High rates of awareness and treatment of hypertension as well as good levels of control were found in this population, probably explained by the long-term surveillance program conducted in the area. Considering the predictors of hypertension management, particular attention should be given to men, residents younger than 60 years, immigrants, and study participants without CVD as these characteristics were predictors of poor outcome.
Julia K. Rohr, F. Xavier Gómez-Olivé, Molly Rosenberg, Jennifer Manne-Goehler, Pascal Geldsetzer, Ryan Wagner, Brain Houle, Joshua A. Salomon, Kathleen Kahn, Stephen Tollman, Lisa Berkman, and Till Bärnighausen. 2017. “Performance of self-reported HIV status in determining true HIV status among older adults in rural South Africa: a validation study.” Journal of the International AIDS Society 20 (1). Publisher's VersionAbstract
Introduction : In South Africa, older adults make up a growing proportion of people living with HIV. HIV programmes are likely to reach older South Africans in home-based interventions where testing is not always feasible. We evaluate the accuracy of self-reported HIV status, which may provide useful information for targeting interventions or offer an alternative to biomarker testing. Methods : Data were taken from the Health and Aging in Africa: A Longitudinal Study of an INDEPTH Community in South Africa (HAALSI) baseline survey, which was conducted in rural Mpumalanga province, South Africa. A total of 5059 participants aged ≥40 years were interviewed from 2014 to 2015. Self-reported HIV status and dried bloodspots for HIV biomarker testing were obtained during at-home interviews. We calculated sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) for self-reported status compared to “gold standard” biomarker results. Log-binomial regression explored associations between demographic characteristics, antiretroviral therapy (ART) status and sensitivity of self-report. Results : Most participants (93%) consented to biomarker testing. Of those with biomarker results, 50.9% reported knowing their HIV status and accurately reported it. PPV of self-report was 94.1% (95% confidence interval (CI): 92.0–96.0), NPV was 87.2% (95% CI: 86.2–88.2), sensitivity was 51.2% (95% CI: 48.2–54.3) and specificity was 99.0% (95% CI: 98.7–99.4). Participants on ART were more likely to report their HIV-positive status, and participants reporting false-negatives were more likely to have older HIV tests. Conclusions : The majority of participants were willing to share their HIV status. False-negative reports were largely explained by lack of testing, suggesting HIV stigma is retreating in this setting, and that expansion of HIV testing and retesting is still needed in this population. In HIV interventions where testing is not possible, self-reported status should be considered as a routine first step to establish HIV status. Keywords  Validation study; South Africa; HIV status; self-report; older adults; public health To access the supplementary material to this article please see  Supplementary Files  under Article Tools online. (Published: 18 July 2017) Rohr J et al.  Journal of the International AIDS Society  2017,  20 :21691 http://www.jiasociety.org/index.php/jias/article/view/21691  |  http://dx.doi.org/10.7448/IAS.20.1.21691
Collin F Payne, Francesc Xavier Gómez-Olivé, Kathleen Kahn, and Lisa Berkman. 2017. “Physical Function in an Aging Population in Rural South Africa: Findings From HAALSI and Cross-National Comparisons With HRS Sister Studies.” J Gerontol B Psychol Sci Soc Sci, 72, 4, Pp. 665-679.Abstract
Objectives: We use recently-collected data from the Health and Aging in Africa: a Longitudinal Study of an INDEPTH Community in South Africa (HAALSI) cohort from Agincourt, South Africa, to describe physical functioning in this aging population, and place the overall level and age-trajectories of physical health in the context of other Health and Retirement Study (HRS) sister studies in low- and middle-income countries (LMICs). Method: We conduct multiple regression to estimate associations of physical functioning assessed from both self-report (activities of daily living [ADL] limitation, self-reported health) and performance (grip strength, gait speed) with socio-demographic and health characteristics in HAALSI, and use fully-interacted regression models to compare age-patterns of physical functioning outcomes cross-nationally. Results: Gender differences in self-reported health are minimal, and men had 30% higher odds of being ADL limited controlling for socio-demographic and health characteristics. Measured physical performance is closely tied with socioeconomic conditions, but self-reported measures have a much smaller or weaker socioeconomic gradient. In international age-adjusted comparisons, the HAALSI sample had lower physical performance outcomes than most comparison populations. Discussion: As the first HRS sister study undertaken in Africa, HAALSI adds vital information on population aging and health in the region. Continuing waves of HAALSI data will be a key resource for understanding differences in the complex processes of disability across LMIC contexts.
2016
Molly S. Rosenberg, F. Xavier Gómez-Olivé, Julia K. Rohr, Brian C. Houle, Chodziwadziwa W. Kabudula, Ryan G. Wagner, Joshua A. Salomon, Kathleen Kahn, Lisa F. Berkman, Stephen M. Tollman, and Till W. Bärnighausen. 9/17/2016. “Sexual behaviors and HIV status: a population-based study among older adults in rural South Africa..” JAIDS Journal of Acquired Immune Deficiency Syndromes, Publish Ahead of Print. Publisher's VersionAbstract

Objective: To identify whether older adults in rural South Africa have unmet needs for HIV prevention.Methods: We analyzed data from a population-based sample of 5059 men and women aged 40 and older from Health and Aging in Africa: Longitudinal Studies of INDEPTH Communities (HAALSI) undertaken in the Agincourt sub-district of Mpumalanga Province, underpinned by the Agincourt health and socio-demographic surveillance system. We estimated the prevalence of HIV (laboratory-confirmed and self-reported) and key sexual behaviors by age and sex. We compared sexual behavior profiles across HIV status categories with and without age-sex-standardization.

Glyn W. Humphreys, Mihaela D. Duta, Livia Montana, Nele Demeyere, Cathal McCrory, Julia Rohr, Kathleen Kahn, Stephen Tollman, and Lisa Berkman. 2016. “Cognitive Function in Low-Income and Low-Literacy Settings: Validation of the Tablet-Based Oxford Cognitive Screen in the Health and Aging in Africa: A Longitudinal Study of an INDEPTH Community in South Africa (HAALSI).” The Journals of Gerontology Series B: Psychological Sciences and Social Sciences. Publisher's VersionAbstract
Objectives: 1. Assess validity of the Oxford Cognitive Screen (OCS-Plus), a domain-specific cognitive assessment designed for low-literacy settings, especially in low- and middle-income countries (LMIC); 2. Advance theoretical contributions in cognitive neuroscience in domain-specific cognitive function and cognitive reserve, especially related to dementia.Method: In a cross-sectional study of a sample of 1,402 men and women aged 40–79 in the Health and Aging in Africa: A Longitudinal Study of an INDEPTH Community in South Africa (HAALSI), we administered OCS-Plus along with health and sociodemographic assessments. HAALSI is a representative sample of older adults in Agincourt, South Africa contributing to normative understanding of cognition in LMIC. We report measure distributions, construct and external validity of the OCS-Plus.Results: OCS-Plus has excellent construct and external validity. Intra-class correlations between similar basic measures of orientation in OCS-Plus and in HAALSI assessments was 0.79, and groups of people performing well on the OCS-Plus verbal memory also showed superior performance on HAALSI verbal memory. The OCS-Plus scores showed consistent associations with age and education and domain-specific associations with alcohol and depression. Younger respondents and the more educated did better on all assessments.Discussion: The OCS-Plus represents a major methodological advance in dementia studies in LMICs, and enhances understanding of cognitive aging.
Stephen M Tollman, Shane A Norris, and Lisa F Berkman. 2016. “Commentary: The value of life course epidemiology in low- and middle-income countries: an ageing perspective.” International Journal of Epidemiology, 45, 4, Pp. 997-999. Publisher's Version
Jennifer Manne-Goehler, Livia Montana, Xavier Gomez-Olive, Julia Rohr, Ryan Wagner, Chodziwadziwa Kabudula, Alisha Wade, Kathleen Kahn, Stephen Tollman, Lisa Berkman, Till Barnighausen, and Thomas Gaziano. 2016. “Human Immunodeficiency Virus (HIV) Infection, Antiretroviral Therapy (ART) Use and Access to Care for Diabetes and Hypertension in Agincourt, South Africa.” Open Forum Infectious Diseases, 3. Publisher's Version
2014
Xavier F Gómez-Olivé, Margaret Thorogood, Philippe Bocquier, Paul Mee, Kathleen Kahn, Lisa Berkman, and Stephen Tollman. 2014. “Social conditions and disability related to the mortality of older people in rural South Africa.” International Journal of Epidemiology, 43, 5, Pp. 1531-1541. Publisher's VersionAbstract
Background: South Africa is experiencing a health and social transition including an ageing population and an HIV epidemic. We report mortality experience of an older rural South African population.Methods: Individual survey data and longer-term demographic data were used to describe factors associated with mortality. Individuals aged 50 years and over (n = 4085) answered a health and quality of life questionnaire in 2006 and were followed for 3 years thereafter. Additional vital events and socio-demographic data were extracted from the Agincourt Health and Demographic Surveillance System from 1993 to 2010, to provide longer-term trends in mortality. Cox regression analysis was used to determine factors related to survival.Results: In 10 967 person-years of follow-up between August 2006 and August 2009, 377 deaths occurred. Women had lower mortality {hazard ratio [HR] 0.35 [95% confidence interval (CI) 0.28–0.45]}. Higher mortality was associated with being single [HR 1.48 (95% CI 1.16–1.88)], having lower household assets score [HR 1.79 (95% CI 1.28–2.51)], reporting greater disability [HR 2.40 (95% CI 1.68–3.42)] and poorer quality of life [HR 1.59 (95% CI 1.09–2.31)]. There was higher mortality in those aged under 69 as compared with those 70 to 79 years old. Census data and cause specific regression models confirmed that this was due to deaths from HIV/TB in the younger age group.Conclusions: Mortality due to HIV/TB is increasing in men, and to some extent women, aged over 50. Policy makers and practitioners should consider the needs of this growing and often overlooked group.