Health and wellbeing of ageing populations in Africa and Asia
Collaboration with INDEPTH sites, WHO, Umeå University, Sweden; University of Warwick, UK; Harvard, Washington, University of Colorado at Boulder, USA
Tollman, with Kahn and Gómez-Olivé, lead INDEPTH research in eight HDSS centres in Africa and Asia on health and wellbeing of ageing populations in these sites. The sites applied a short version of the WHO-SAGE instrument to adults 50+ to assess baseline measures of physical and cognitive function and established cohorts of older adults in Africa and Asia (2006/7). Comparative and site-specific publications have been published. First round data collection in Agincourt occurred 2006; there was a 2nd round,, including a module on health care utilization of people 50 years and older, in 2010. Analyses and national comparisons using the 2010 data in the established cohorts is currently underway.
An NIH Program-Project grant proposal for work linking adult self-reported physical and cognitive function and quality of life with subsequent survival was submitted September 2012, with review expected Feb 2013.
AWI-Gen (Africa, Wits-INDEPTH Partnership for the GENomic study of body composition and CMD risk)
Michele Ramsay, Osman Sankoh, Steve Tollman and colleagues Oct 2016
AWI-Gen is a Collaborative Centre that is part of the Human Heredity and Health in Africa (H3Africa) Consortium (www.H3Africa.org). The long-term vision of AWI-Gen is to build sustainable capacity for research that leads to an understanding of the interplay between genetic, epigenetic and environmental risk factors for obesity and related cardiometabolic diseases (CMD) in sub-Saharan Africa. Under the auspices of the University of the Witwatersrand (Wits) and the International Network for the Demographic Evaluation of Populations and Their Health in Low- and Middle- Income Countries (INDEPTH), it will capitalize on the unique strengths of existing longitudinal cohorts, including the urban Soweto and rural Agincourt studies in South Africa (Wits based), and the well established INDEPTH health and demographic surveillance centres (HDSS) in Kenya, Ghana, Burkina Faso and South Africa. The centers offer established infrastructure, trained fieldworkers, long-standing community engagement, and detailed longitudinal phenotypic data, focusing on obesity and cardiometabolic health. Key strengths are harmonized phenotyping across sites, building on strong existing cohorts, and representation of the geographic and social variability of African populations. We aim to: 1. Build sustainable infrastructure (biobanks and laboratories) and capabilities (well characterized population cohorts, genotyping and bioinformatics) for genomic research on the African continent; 2. Understand the genomic architecture of sub-Saharan populations from west, east and south Africa to guide genomic studies (high throughput SNP and CNV arrays using unrelated individuals and family trios to improve the accuracy of haplotype analyses) and; 3. Investigate the independent and synergistic genomic contributions to body fat distribution (BMI, hip/waist circumference, subcutaneous and visceral fat) in these populations considering the relevant environmental and social contexts (rural/urban communities, quickly transitioning obesity prevalence, differential HIV, TB, and malaria infection histories). We will investigate the effect of obesity and fat distribution on the risk for CMD in the longitudinal cohorts. Recruitment of just over 12,000 participants was completed at the end August 2016 and data analysis is in progress.
HAALSI – Health and Aging in Africa: Longitudinal Studies of INDEPTH communities
INDEPTH Health and Demographic Surveillance System centres – Agincourt, South Africa-Stephen Tollman, Ifakara, Tanzania-Honorati Masanja, Navrongo, Ghana-Cornelius Debpuur.
Collaborating institutions – INDEPTH Network, Centre for Global Health Research, Umeå University, Sweden, Centre for Population and Development, Harvard School of Public Health, Harvard University, USA
The study is nested in three Health and Demographic Surveillance System centres in sub-Saharan Africa countries at different stages of the epidemiologic transition. A stratified sample of equal numbers of both men and women, age 50+ years, was selected from each of the study sites with calculation of the sampling weights for the varying sampling fractions so that our sample is representative of the centre population as per the most current site census. We aim to enrol at least 4000 people in each country for a total of 12 000 participants. To maximize our longitudinal information, we enrolled large numbers of men and women who completed earlier waves of the WHO Study on Global Ageing and Adult Health (SAGE) in each of the three countries and additionally include all participants in the smaller SAGE long questionnaire.
We then drew on the baseline wave of HAALSI to obtain a 10% subsample in whom a detailed clinical substudy was carried out. This substudy included determination of traditional and novel blood based biomarkers, body fat distribution and ascertainment of cardiovascular outcomes, such as peripheral vascular disease and ischaemic heart disease. A second wave of measures will be obtained three years after the initial survey in the Agincourt site to allow determination of trends and incidence rates.
Selected “cores” of experts will guide the projects. Three key cores are the Mortality core, the Measures and Methods core and the Data Collection and Management core. The Mortality core will assist all subprojects by providing accurate, consistent, comparable measures of all-cause and cause-specific mortality and assuring that migration is appropriately addressed to provide a full accounting of the study cohorts. The Measures and Methods core will develop and disseminate a harmonized set of measurement instruments and protocols, develop the analytic basis for instrument testing and validation, in close collaboration with the Data Collection and Management Core, and provide a toolkit for standardized data analysis and synthesis of research findings. The Data Collection and Management core will establish rigorous, standardized systems to support data collection and management of household surveys in three sites, and a second wave in Agincourt as well as integrate data on mortality and selected information from the HDSS censuses to produce analytic data sets and documentation and preserve all data for archiving. This core will also develop study protocols, develop and implement common systems of data collection, data capture, and data management and pilot test all study instruments.
Feedback about this study was given to all of the communities in the Agincourt HDSS in the form of an informative, one-page fact sheet. To see the fact sheet, click here.
Chronic care – Nkateko Trial (Hope)
Collaboration with MRC/Wits Health Policy Research Group, Warwick Medical School UK, and the Chief Directorate for Chronic Disease in the DOH
A cluster randomised trial (2013-16) focused on integrated chronic care will evaluate clinic-based lay health worker support for community health worker efforts to manage NCDs, hypertension in particular. Work builds on prior studies addressing stroke, cardiovascular risk and the barriers to chronic care.
In South Africa, hypertension is highly prevalent. We have found that more than half (61%) of adults in the Agincourt HDSS have hypertension and in only
a few (9%) of them have blood pressure well controlled using medication. Hypertension is a chronic condition requiring long term medication but until recently the primary care clinics in South Africa were only organised to deal with short term conditions. The government has recognised the problem and is reorganising clinics to also deal with chronic conditions, such as HIV and hypertension. We will test whether providing an extra lay health worker, to work alongside the nurses in the clinics focusing on the care of chronic conditions, will help to improve the care of people with hypertension. We will carry out research in eight clinics that provide care to the people living in the Agincourt HDSS. We will randomly choose four clinics where we will provide the lay health workers for 15 months. We will test the effect of these lay health workers by doing two population surveys of blood pressure, one before we start the intervention and one as soon as we finish. In addition we will set up a clinic/census link so that we can find out which people (age, sex, place of residence, etc.) are using the clinics and whether that changes when the intervention is introduced. We will also carry out a number of interviews with different people during the intervention to identify some of the barriers and facilitators to providing good care of people with hypertension. The findings from this trial will be relevant for improving the care of all chronic diseases.
HIV/NCD prevalence study (Ha Nakakela)
Collaboration with Wits Public Health, Colorado at Boulder and Washington Universities, USA
Study of 7,428 people aged 15 years and older to measure HIV prevalence, biomarkers for non-communicable chronic diseases (mainly cardiovascular and diabetes) using dried blood spots, physical measurements including blood pressure and anthropometry, and lifestyle and sexual risk behaviours. HIV result could be obtained at the health centre. Blood pressure and glucose results were given at the household with referral to nearest health facility for abnormal results. Plans are to conduct an incidence study in 2014.
Figure 1. HIV prevalence by sex and age of Agincourt 2010 estimates *Age group 60-64 includes everyone aged 60+ 1
1. Francesc Xavier Gómez-Olivé , Nicole Angotti , Brian Houle , Kerstin Klipstein-Grobusch, Chodziwadziwa Kabudula , Jane Menken , Jill Williams , Stephen Tollman & Samuel J. Clark (2013): Prevalence of HIV among those 15 and older in rural South Africa, AIDS Care: Psychological and Socio-medical Aspects of AIDS/HIV, DOI:10.1080/09540121.2012.750710 . To link to this article: http://dx.doi.org/10.1080/09540121.2012.750710
2.Francesc Xavier Gomez-Olive, Margaret Thorogood, Benjamin Clark, Kathleen Kahn and Stephen Tollman (2013). Self-reported health and health care use in an ageing population in the Agincourt sub-district of rural South Africa . Glob Health Action 2013, 6: 19305. To link to this article http://dx.doi.org/10.3402/gha.v6i0.19305