Focal Areas

HAALSI consists of five main projects. Each project uses the same household survey and assessment tools to draw on collective information from HAALSI waves 1, 2, and 3. While the individual projects have specific aims, they are tightly integrated with each other. The main objectives of each project are described below:

Cognition & Dementia

Principal Investigator: Lisa F. Berkman

Most work on dementias comes from high-income countries where landmark studies have identified risks, prevalence, and costs of dementia. Little is known about dementia in low- and middle-income countries. Due to the burden of HIV, the legacy of apartheid, and low levels of educational attainment, South Africa may exhibit distinct epidemiological patterns of dementias and provide novel insights into risk and protective factors for development of cognitive decline.

With this context in mind, the Cognition & Dementia project aims to (1) determine the incidence and prevalence of dementia and mild cognitive impairment (MCI); (2) identify social and economic risk and resilience factors affecting cognitive decline and dementia; and (3) evaluate associations of Apo-E and markers of biological aging related to telomeres with cognitive decline. This understanding of the patterns, risk factors, and projected public health burden of all-cause dementia, mild cognitive impairment (MCI), and cognitive decline in South Africa can inform the planning health and social services that promote cognitive health among the elderly.

Cardiometabolic Disease

Principal Investigators: Stephen M. Tollman & Thomas Gaziano 

In the wake of epidemiologic, social, and economic transitions, cardiovascular disease (CVD) has become the leading cause of death globally. Rural South Africa is in the midst of these transitions, and the population is rapidly aging. Yet to date, reliable data on chronic cardiometabolic diseases (CMD) in the region, including CVD and diabetes, remains scarce. 

The goals of the Cardiometabolic Disease project are to (1) evaluate the scale and trajectory of CMD, including the prevalence, incidence and mortality of key conditions, and identify their associated risk factors; (2) evaluate the effects of social determinants on CMD risk; (3) develop models for identifying individuals at high risk for CMD and generate projections of future population-level CMD burden; and (4) assess the effects of South Africa’s 2013 salt legislation on CMD risk. In the long term, understanding these aspects of CMD in HAALSI can be used to inform health and social policy in South Africa and beyond. 

HIV & Treatment

Principal Investigators: Till Bärnighausen & Kathleen Kahn

HIV treatment and prevention in sub-Saharan Africa (SSA) have been the single biggest focus of global health initiatives and funding over the past 15 years. The widespread use of antiretroviral therapy (ART) has led to survival of HIV+ populations to older ages and decreased HIV incidence in younger populations. As a result, the population of people living with HIV is rapidly aging, and older adults will be key to the long-term success of the HIV response. Despite the increasing importance of older adults for the future of HIV programs and policies, most HIV prevention and treatment programs target youth and middle-aged adults.

To address the needs of the aging HIV+ population in rural South Africa, the HIV & Treatment project aims to (1) identify the key modifiable barriers to progression across the stages of the HIV prevention and treatment cascades among older adults; (2) establish the effects of home-based delivery of HIV self-tests and an age-appropriate culturally-relevant motivational and instructional interactive app on HIV self-testing, HIV status knowledge, and linkage to care; and (3) establish the long-term impacts of HIV treatment on healthy aging. These goals will provide insight on how to better integrate older adults into HIV programs, leading to reduced HIV incidence, fewer co-morbidities, and improved survival.

Public Policies & Health

Principal Investigators: David J Canning & Mark A Collinson

Strong socioeconomic gradients in health exist throughout the world. Results from the baseline wave of HAALSI indicate that socioeconomic patterns in health inequalities persist among older adults in rural South Africa. Public policies are frequently used to improve health and reduce socioeconomic inequalities. In South Africa these policies include social grants, such as old age pensions, disability grants, and care-in-aid grants, that are large relative to household income. Additionally, recent legislation aims to improve health by reducing the consumption of sugar sweetened beverages (SSBs) and of salt from processed foods. 

A central question is the extent to which such public policies can improve the health of older adults and reduce health disparities. Therefore, the Public Policies & Health project strives to (1) measure and describe the relationship between socioeconomic conditions and the health and well-being of older people in rural South Africa; (2) determine how social grants affect the health of older adults in rural South Africa, and ascertain the reasons for lack of uptake of grants among older people who appear to meet eligibility criteria; and (3) assess the effect of the introduction of (a) new taxes on SSBs and (b) limits on salt in processed foods on consumption and health risk factors. Successful completion of these aims will provide a rigorous evidence base for the effect of social policies on the health of older adults.


Principal Investigators: Joshua A. Salomon & F. Xavier Gómez-Olivé Casas    

Multimorbidity—the coexistence of more than one chronic condition—increases the risks for declines in physical and cognitive functioning, hospitalization, and mortality. Thus, there is considerable interest in understanding patterns, determinants, and consequences of multimorbidity in aging populations. The rapidly aging population of sub-Saharan Africa is likely to produce a rising burden of multiple chronic conditions. Research on multimorbidity to date has focused predominantly on high-income countries, and on healthcare settings rather than on the general population. 

The objectives of the Multimorbidity project are to (1) develop a comprehensive portrait of the epidemiology of multimorbidity among older adults in rural South Africa; (2) evaluate the consequences of multimorbidity on mortality, physical and mental function, and wellbeing; (3) assess the implications of multimorbidity for healthcare service utilization, continuity of care, and health care spending; and (4) quantify the relationship between multimorbidity and frailty, and associated excess mortality risks, and develop integrative measures of healthy life expectancy. These data will assist in identifying the most vulnerable of the elderly population and guide development of clinical and health policy interventions.