African National Income Dynamics Study Research Articles

Impact of pre-existing depression and food insecurity on the trajectory of depressive symptomatology during the COVID-19 pandemic outbreak in South Africa: A panel analysis of nationally representative South African data

We investigated the trajectory of depressive symptoms (“depression”) from the start of the COVID-19 pandemic in South Africa (March 2020) until 2021, between individuals with and without pre-pandemic depression, specifically regarding the role of food security. Our investigation used publicly available panel data (N = 6,930) from the South African National Income Dynamics Study Coronavirus Rapid Mobile Survey (SA-NIDS-CRAM from 2020–2021) on those who had also participated in the pre-pandemic South African National Income Dynamics Study (SA-NIDS, 2017) depression interview. We investigated trends in depressive symptomatology (based on a 2-item Patient Health Questionnaire) at SA-NIDS-CRAM Wave 2 (July 2020), Wave 3 (February 2021) and Wave 5 (May 2021). Generalized estimating equations (GEE) with post-estimation linear combinations of estimators were fitted to investigate the roles of pre-pandemic depression (based on 2017 SA-NIDS data) and food insecurity during the pandemic on depressive symptomatology. During the pandemic, the highest levels of depression were observed consistently among those with pre-pandemic depression and food insecurity; and were lowest among those without pre-pandemic depression and food security. Depressive symptomatology rose in nearly equal magnitude during the early phases of the pandemic in two groups: those without pre-pandemic depression but food insecure during the pandemic; as well as those with pre-pandemic depression but food secure during the pandemic. However, this dynamic changed later in the pandemic, when higher depressive symptomatology was observed in the group with both pre-pandemic depression and food insecurity, widening the gap between them from Wave 3 (adj β = 0.63, p < 0.01) to Wave 5 (adj β = 0.79, p < 0.01). Our results highlight the importance of addressing both population mental health and food insecurity, particularly at the early stages of a crisis/disaster. As we showed that mental health impact is linked to food insecurity during a pandemic, strengthening social protection measures, especially around food and nutrition, would help build resilience to crises in the long term.

Multimorbid life expectancy across race, socio-economic status, and sex in South Africa

Multimorbidity is increasing globally as populations age. However, it is unclear how long individuals live with multimorbidity and how it varies by social and economic factors. We investigate this in South Africa, whose apartheid history further complicates race, socio-economic, and sex inequalities. We introduce the term ‘multimorbid life expectancy’ (MMLE) to describe the years lived with multimorbidity. Using data from the South African National Income Dynamics Study (2008–17) and incidence-based multistate Markov modelling, we find that females experience higher MMLE than males (17.3 vs 9.8 years), and this disparity is consistent across all race and education groups. MMLE is highest among Asian/Indian people and the post-secondary educated relative to other groups and lowest among African people. These findings suggest there are associations between structural inequalities and MMLE, highlighting the need for health-system and educational policies to be implemented in a way proportional to each group’s level of need.

Preventing Stunting in South African Children Under 5: Evaluating the Combined Impacts of Maternal Characteristics and Low Socioeconomic Conditions

More than 140 million children under five suffered from stunting in 2020. This highlights the ongoing challenge of addressing childhood malnutrition globally. We utilized data from a nationally representative sample of children under five years of age (n = 14,151) who participated in five cycles of the South African National Income Dynamics Study (SA-NIDS) (2008–2017). We estimated the proportion of stunted children attributed to the mothers’ anthropometric characteristics and socioeconomic conditions. We also quantified the population-level burden of low-socioeconomic conditions on hunger/food insecurity among pregnant women (n = 22,814) who participated in the nine rounds of the South African General Household Surveys (GHS) (2008–2021). Results from weighted-multivariate logistic regression were incorporated into the population-level impacts of correlates of stunting and low-socioeconomic conditions. The prevalence of stunting declined from 25% in 2008 to 23% in 2017. Mothers’ anthropometric measures (underweight/height < 160 cm), marital status, low education, absence of medical insurance and low-socioeconomic conditions were all identified as the most influential risk factors for stunting. Their population-level impacts on stunting increased substantially from 34% (in 2008) to 65% (in 2017). Comprehensive strategies emphasizing enhanced food security, extended breastfeeding, appropriate nutrition, and access to adequate healthcare and education are urgently needed to reduce the burden of food insecurity low-socioeconomic, malnutrition, and its long-term consequences.

What drives the willingness to get vaccinated against COVID-19 in South Africa?

The willingness to get vaccinated in South Africa is among the highest in the world, measuring at 76%. This study investigated the impact of individual risk beliefs, self-reported health status, and familiarity with someone with coronavirus disease 2019 (COVID-19) on the willingness to get vaccinated in South Africa. Data were obtained from the Wave 5 of the South African National Income Dynamics Study &amp;ndash; Coronavirus Rapid Mobile Survey. Data were analyzed using descriptive statistics and binary logistic regression. More than 53% of the population believed that they were not at risk of COVID-19; 71.8% believed that they were in good health; and 31.6% knew someone with COVID-19. Beliefs (odds ratio [OR]: 1.287), health status (OR: 1.064), and COVID-19 case familiarity (OR: 1.034) were associated with willingness to get vaccinated. Other associations remained positive in the adjusted model. The relationship between case familiarity and willingness to get vaccinated shows that knowing someone who died of COVID-19 or suffered from the discomfort induced by the disease may drive other individuals to get vaccinated.

Linking Care and Support Systems to Improve Childhood Malnutrition: Early Childhood Development Practitioners’ Perceptions of Integrating Multisectoral Systems in South Africa

Introduction: Child malnutrition is a persistent global challenge. It is the cause of nearly 45% of global child mortalities. To ensure positive child health outcomes, integrated multisectoral approaches among families, communities, and government systems to ensure positive child health outcomes are neccesary. Objectives: This study identifies how different care support systems can be linked to ensure optimal childhood nutrition outcomes in South Africa. This is through multisectoral approaches from the early childhood development (ECD) practitioners' perspective. Materials and Methods: We integrated the components of the different support systems and multisectoral approaches. The conceptional framework of the causes of malnutrition by The United Nations Children's Fund (UNICEF) recognizes that malnutrition is due to inadequate care services, diet, and care practices influenced by individual, household, community, and structural determinants. While the Nurturing Care Framework, which looks at how policies and services can support families, parents, and other communities in providing nurturing care. Design: A sequential mixed methods approach was used. For the quantitative method, we did a cross-sectional descriptive analysis of 2 966 children who were under-five years' old in the 2017 South African National Income Dynamics Study (NIDS) between July and August 2022, we conducted five in-depth interviews with ECD practitioners using this qualitative method, and the data was analyzed using thematic analysis. Data was triangulated to understand the factors influencing children’s nutritional outcomes and to provide the narratives of ECD practitioners. This enabled us to highlight challenges and opportunities in linking children to services they need. Results: This study showed that 22.16% of children were stunted, 16.40% were overweight, and 5.04% were underweight. ECD practitioners reported a lack of support received at health facilities and other social services when making referrals, a lack of parental support in nutrition programmes, systemic challenges experienced in getting ECD centers registered, and the ECD's inability to qualify for subsidized nutrition grants. Conclusion: It is critical for us to understand the challenges and opportunities for multisector collaboration. This understanding will enable strategies and policies aimed at providing efficient and effective service referral and service delivery to improve childhood malnutrition in South Africa.

Water, sanitation and depression in rural communities: evidence from nationally representative study data in South Africa

ABSTRACT Clean water and sanitation provisions are essential for good hygiene and health, with rural South Africa facing a simultaneous access crisis of both, the direct health effect of restricted access to both on mental health remaining scarce and largely overlooked. This study investigated the association between access to clean water and sanitation on depression in rural South Africa utilizing the most recent data (year 2017) from the South African National Income Dynamics Study. Our study outcome was depression, based on the 10-item abridged version of the Center for Epidemiologic Studies Depression Scale (data available in SA-NIDS), the main exposures being access to clean water and adequate sanitation facilities (i.e. flushing toilets). Two types of analyses were conducted: first, adjusted logistic regression models were fitted to assess the relationship between lack of access to clean water and adequate sanitation to depression. Second, we conducted mediation analysis to investigate whether access to clean water mediated the relationship between lack of access to toilets and depression. A high proportion of rural participants lacked access to clean water (n = 6,188, 47.6%) and adequate toilets (n = 9,797, 81.6%). The regression analyses indicated that lack of access to both clean water (OR = 1.21, 95% CI: 1.06–1.39) and adequate sanitation (OR = 1.36, 95% CI: 1.10–1.69) were significantly associated with greater odds of depression. The mediation analysis indicated that access to clean water partially mediated the relationship between lack of access to adequate sanitation and depression, the total mediated effect being 18.2% (95% CI: 11.0%–51.0%). Most rural communities in South Africa lack access to basic services that are essential for human dignity and a decent quality of life, leading to opportunities for poor mental health, with its various consequences for socio-economic development and personal wellbeing, including avoidable depression.

Examining maternal depression, birthweight and linear growth: Findings from the South African National Income Dynamics Study

Background. Literature is inconclusive regarding an association between maternal depression, low birthweight (LBW) and stunting in early childhood. While some studies have found an association, others have not. Maternal food insecurity is a risk factor for both maternal depression and reduced linear growth in early childhood. &#x0D; Objective. This study examined the relationship between maternal depression, food insecurity, LBW and stunting in the first five years of life. The study employed longitudinal data of South African women and children from the National Income Dynamics Study (NIDS). &#x0D; Methods. Mothers were classified into four groups: food insecure and depressed; food insecure only; depressed only; and neither food insecure nor depressed. During data collection, 22% of women were pregnant and the remaining 78% were pre-conception. The primary outcomes were low birthweight and height-for-age (HAZ) scores. Generalised Linear Mixed Effects (GLME) models were used to account for women having more than one child. GLME models with a Gaussian link function were used to compare mean differences in birthweight and HAZ scores. Multivariable regression models were used to examine factors associated with depression. &#x0D; Results. Food insecurity was significantly associated with depression among pre-conceptional and pregnant women. There was no statistically significant difference in birthweight or linear growth across groups, but this may be influenced by proximity of depression measurement in relation to outcomes. &#x0D; Conclusion. Food insecurity is a potentially modifiable risk factor for depression and may be a confounding factor in studies that have found associations between depression and child health outcomes.

Depression onset and its association with community HIV prevalence: A geospatial and panel analyses of nationally representative South African data, 2015–2017

• We compared depression onset overtime among depression-free individuals based on the HIV prevalence of their communities. • Communities with higher HIV prevalence had higher prevalence of depression onset. • Higher community HIV prevalence was associated with depressive consequences for individual residents over time. The scaling up of antiretroviral therapy services over the past decades has led to a remarkable reduction in HIV infections and HIV-related deaths in South Africa (SA). While this is a step in the right direction, it brings a new public health challenge into focus, namely psychological challenges associated with such chronic and often stigmatising condition in SA, home to the largest HIV epidemic. Given the current lack of national-level evidence, we investigated the role of the HIV epidemic on depression onset in SA using nationally representative panel data from the South African National Income Dynamics Study (SA-NIDS). Our incident cohort consisted of 13,020 sampled adult participants who were depression-free in Wave 4 (baseline year of 2015). We then measured the risk of depression onset in Wave 5 (year 2017) based on the level of HIV prevalence in the community where study participants resided at baseline. A High-resolution map of HIV spatial heterogeneity (i.e., community HIV prevalence) was generated using ordinary kriging mapping methods from a separate nationally representative data source that corresponded to the investigation period. Geospatial analyses were conducted to identify the spatial structure of HIV and depression onset, and generalised estimating equations (GEE) regression models were fitted to determine the risk of depression onset over time based on community HIV prevalence. Our geospatial analyses indicated that HIV and depression onset prevalence spatially overlapped in the eastern part of the country, particularly in Gauteng, KwaZulu-Natal, Mpumalanga, and Free State province. The GEE regression analyses indicated that individual residency in a community with high HIV prevalence was significantly associated with a higher risk of depression than a low HIV prevalence community (adjusted odds ratio =1.45, 95% CI=1.12-1.48). For the first time, we identified a geospatial overlap between HIV and depression, with a greater risk of depression onset in high HIV prevalence communities, at a national scale in SA. There is a need for place-based policy interventions that prioritise the availability of and access to mental health services in high HIV prevalent SA communities, in an ageing HIV epidemic.

Modelling of South African Hypertension: Application of Classical Quantile Regression

Background: High blood pressure, medically known as hypertension is the major risk factor for cardiovascular diseases (CVDs) and premature death globally. The aim of the present study was to explore possible interactions amongst systolic blood pressure`s (SBP) and diastolic blood pressure`s (DBP) risk factors in South Africa. Methods:A retrospective study was conducted using data acquired from the South African National Income Dynamics Study Wave 5, Household Survey which was carried out in 2017-2018.A final data set of 21 180 adults was utilized for data analysis. An application of the hierarchical group-lasso approach to detect interactions between SBP`s and DBP`s risk factors and classical quantile regression analysis were performed in this study. Results: By using only upper quantilesbody mass index (BMI), age, race, never exercised, and the following nine interactions: BMI and age, BMI and gender male, age and never exercised, gender male and race African, race coloured and depression some or little of the time, BMI and cigarette consumption, age and race white, gender male and employment status, never exercised and cigarette consumptionwere found to be significantdeterminantsof hypertension in South Africa. Conclusion: The evidence of this study suggests that it is ideal to consider interactions amongst risk factors when modelling hypertension. Bangladesh Journal of Medical Science Vol. 21 No. 04 October’22 Page : 772-781

Inequity in the Distribution of Non-Communicable Disease Multimorbidity in Adults in South Africa: An Analysis of Prevalence and Patterns.

Objectives: The present study examined the prevalence and patterns of non-communicable disease multimorbidity by wealth quintile among adults in South Africa. Methods: The South African National Income Dynamics Study Wave 5 was conducted in 2017 to examine the livelihoods of individuals and households. We analysed data in people aged 15 years and older (N = 27,042), including self-reported diagnosis of diabetes, stroke, heart disease and anthropometric measurements. Logistic regression and latent class analysis were used to analyse factors associated with multimorbidity and common disease patterns. Results: Multimorbidity was present in 2.7% of participants. Multimorbidity was associated with increasing age, belonging to the wealthiest quintile group, increasing body mass index and being a current smoker. Having secondary education was protective against multimorbidity. Three disease classes of multimorbidity were identified: Diabetes and Hypertension; Heart Disease and Hypertension; and Stroke and Hypertension. Conclusion: Urgent reforms are required to improve health systems responsiveness to mitigate inequity in multimorbidity patterns in the adult population of South Africa as a result of income inequality.

Modelling of South African Hypertension: Application of Panel Quantile Regression.

Hypertension is one of the crucial risk factors for morbidity and mortality around the world, and South Africa has a significant unmet need for hypertension care. This study aims to establish the potential risk factors of hypertension amongst adults in South Africa attributable to high systolic and diastolic blood pressure over time by fitting panel quantile regression models. Data obtained from the South African National Income Dynamics Study (NIDS) Household Surveys carried out from 2008 to 2018 (Wave 1 to Wave 5) was employed to develop both the fixed effects and random effects panel quantile regression models. Age, BMI, gender (males), race, exercises, cigarette consumption, and employment status were significantly associated with either one of the BP measures across all the upper quantiles or at the 75th quantile only. Suggesting that these risk factors have contributed to the exacerbation of uncontrolled hypertension prevalence over time in South Africa.

Stressful life events, neighbourhood characteristics, and systolic blood pressure in South Africa.

The relationship between negative events, neighbourhood characteristics, and systolic blood pressure in developing countries is not well-documented, particularly using longitudinal data. To explore this relationship, we analysed panel data from the first three waves of the South African National Income Dynamics Study using a correlated random effects model adjusted for confounding risk factors. Our sample comprised of 15,631 respondents in 2008, 14,443 respondents in 2010/2011, and 14,418 respondents in 2012, all aged above 15 years. The prevalence of at least one negative household event across the three waves was approximately 30%. In any of the three waves, the adjusted prevalence of hypertension was 23.84%. This share was 21.75% in 2008 (95% CI 18.06-25.44), 23.16% in 2010/11 (95% CI 19.18-27.14), and 18.39% in 2012 (95% CI 16.03-20.75). In our adjusted correlated random effects model, we found that systolic blood pressure was significantly higher among respondents from households that reported death of a household member (0.85 mmHg; p = 0.02) and a reduction in grant income and remittances (2.14 mm Hg; p = 0.01). We also found no significant association between systolic blood pressure and neighbourhood income level. In a country with social and economic challenges, our results indicate that grief and negative financial events are adversely associated with blood pressure, which may explain in part the significant burden of hypertension in low- and middle-income countries.

Quantifying the impacts of clean cooking transitions on future health-age trajectories in South Africa

Reliance on highly polluting cooking technologies poses a significant risk for human health. This study quantifies and compares the impact of different clean cooking access scenarios on future health-age trajectories among population subgroups in South Africa. Using microdata from five waves of the South African National Income Dynamics Study, we develop a dynamic microsimulation model and a composite metric of individual health status that is used to explore how health status changes under alternative access scenarios for the period 2010–2030. We find that there are clear gains of using clean cooking technologies for population health, and that electrification alone does not improve health status, if it is not accompanied by an increase in the use of clean cooking technologies in homes. Our results imply that achieving universal access to clean cooking in South Africa can by itself improve average population health by almost 4% by 2030 compared to a scenario without clean cooking technologies, with the health of individuals of genders and races with the poorest health and well-being endowments improving the most. Thus, clean cooking can contribute to narrowing existing inequalities by improving health for the most vulnerable population groups that disproportionately depend on polluting cooking technologies.

Community disaster exposure and first onset of depression: A panel analysis of nationally representative South African data, 2008-2017.

Sub-Saharan Africa faces unprecedented disasters, with climate change expected to exacerbate the frequency and severity of unpredictable and stressful catastrophic events. Unlike developed nations, reconstruction in developing nations is hindered by resource constraints, with certain communities potentially experiencing multiple and enduring effects of disasters. Despite the potential danger of such cumulative community disaster exposure on mental health (e.g. depression), large-scale population-level evidence for the region is limited. We investigated the association between exposure to cumulative disaster and the first onset of depression in a nationally representative survey in South Africa. We used panel data from the South African National Income Dynamics Study (SA-NIDS) from 2008-2017, consisting of 17,255 adult study participants who were depression free at baseline. Risk of first depression onset between individuals exposed and unexposed to community disaster was measured, accounting for multiple disaster exposure over time by fitting generalized estimating equation (GEE) regression models. Data on the geographic location of disasters were obtained from the South African government gazette, and mapped with the government delineated SA-NIDS households' locations. Of the sampled individuals, 2,986 were exposed to disaster during the study duration (17.3%). Increased cumulative community disaster was significantly associated with the likelihood of depression onset (adjusted relative risk [aRR] = 1.20, p<0.01, 95% CI: 1.09-1.33), even after controlling for socio-demographic factors. In sub-group analyses, greater likelihood of depression onset was found among females [but not in men] (aRR = 1.23, p<0.01, 95% CI: 1.09-1.38), Black African [but not in other population group] (aRR = 1.21, p<0.01, 95% CI: 1.09-1.36), lower education attainment group [but not in tertiary and above educational attainment group] (aRR = 1.20, p<0.01, 95% CI: 1.08-1.33), and lower income attainment group [but not in the top income quartile group] (aRR = 1.24, p<0.01, 95% CI: 1.11-1.38), due to cumulative community disaster. Although cumulative community disaster exposure was significantly associated with the first onset of depression, its negative impact may be more pronounced among individuals considered chronically socially vulnerable (i.e. the groups above) in South Africa. Given that many individuals in South Africa rely on social, food parcel relief, and health services from government/public sector, timely access to community-based supportive intervention is needed for disaster survivors, prioritizing socially vulnerable groups to help mitigate problems associated with mental health challenges.

Intermarriage on Subjective Social Status and Spousal Dissimilarity in Life Satisfaction of Co-resident Heterosexual South African Couples

The aim of this study is to determine how intermarriage on subjective social status is associated with spousal dissimilarity in life satisfaction in co-resident heterosexual couples in South Africa. We apply fixed effect ordered logit regression models to a sample of 8652 married and cohabiting dyads constructed from the longitudinal and nationally representative South African National Income Dynamics Study. We find no spousal dissimilarity in overall life satisfaction under pure homogamy. In wife advantaged and currently hypogamic relationships females are more satisfied with life than their male partners, whereas the opposite is observed in husband advantaged and currently hypergamic relationships as well as in wife exchanges. Intermarriage on subjective social status may put marriages and relationships at risk of dissolution due to its association with spousal dissimilarity in overall life satisfaction. Further research is required to present a more complete and integrated account of how spousal dissimilarity in subjective well-being may mediate the impact of intermarriage on the dissolution of unions and relationships.

Modelling of South African Hypertension: Comparative Analysis of the Classical and Bayesian Quantile Regression Approaches.

Hypertension has become a major public health challenge and a crucial area of research due to its high prevalence across the world including the sub-Saharan Africa. No previous study in South Africa has investigated the impact of blood pressure risk factors on different specific conditional quantile functions of systolic and diastolic blood pressure using Bayesian quantile regression. Therefore, this study presents a comparative analysis of the classical and Bayesian inference techniques to quantile regression. Both classical and Bayesian inference techniques were demonstrated on a sample of secondary data obtained from South African National Income Dynamics Study (2017–2018). Age, BMI, gender male, cigarette consumption and exercises presented statistically significant associations with both SBP and DBP across all the upper quantiles . The white noise phenomenon was observed on the diagnostic tests of convergence used in the study. Results suggested that the Bayesian approach to quantile regression reveals more precise estimates than the frequentist approach due to narrower width of the 95% credible intervals than the width of the 95% confidence intervals. It is therefore suggested that Bayesian approach to quantile regression modelling to be used to estimate hypertension.

Estimating the price elasticity of demand for cigarettes in South Africa using the Deaton approach

ObjectiveTo estimate the price elasticity of demand for South Africa and thereby contribute to growing the evidence base of the likely impact of excise taxes on cigarette demand in low-income...

Chronic Child Poverty and Health Outcomes in South Africa Using a Multidimensional Poverty Measure

In this paper, I examine the differences in health outcomes between children residing in poor and non-poor households. In order to identify household poverty, I make use of the framework of multidimensional poverty as introduced by Alkire and Foster (Journal of Public Economics, 95(7–8), 2011). I follow the poverty status of children (defined as individuals aged 18 years or younger) over the period 2012- 2017, using the last three waves of the South African National Income Dynamics Study (NIDS). I find great disparities in health outcomes among children depending on the classification of the household as being poor or non-poor. In addition, children residing in households which are chronically poor (i.e. are observed to remain in poverty over time) have worse health outcomes than children residing in households which move in and out of poverty, pointing towards the negative effects of poverty traps. Finally, I rely on the previous work conducted by Wagstaff et al. (Journal of Public Health, 94(5), 726-736, 2004) to explore some of the household circumstances which may alleviate or exacerbate socio-economic child health inequalities in South Africa. These include access to the labour market, maternal education, water and sanitation, and social norms (which include the prevalence of female-headed households and the decision-making power of women in the household).

Family structure and socio-demographic factors associated with binge drinking among adolescents in South Africa

ABSTRACT Binge drinking is associated with risky behaviours and long-term addiction. Among adolescents, binge drinking should be prevented to avoid these and other hazardous consequences. Adolescent behaviours are known to be influenced by their household and family structures. However, the association between family structure and binge drinking in developing countries remains unknown. The purpose of this study is to examine the role of various family structures and sociodemographic factors on binge drinking among adolescents in South Africa. This cross-sectional study uses data from the South African National Income Dynamics Study (NIDS) Wave 4 (2014/15). The study includes adolescent (15–19 years old) males and females. A total of 79,638 (35.8%) adolescents reported binge drinking. The results show that among the adolescents who binge drink, 60% are males and 40% are females. Binge drinking increases with age of the adolescents and 62% of adolescents in multigenerational households (parent(s) and grandparent(s)) binge drink. The odds of binge drinking are higher among those living with their grandparent(s) and parent(s) [OR: 1.30, p-value < 0.05], females [OR: 2.06, p-value < 0.05], those in the ‘average’ household income bracket [OR: 2.00, p-value < 0.05] among others. In conclusion, family structure and other socio-demographic factors are associated with binge drinking among adolescents. These results could be used to inform family-orientated programmes which address binge drinking by addressing several generations of family members.

Systolic blood pressure and 6-year mortality in South Africa: a country-wide, population-based cohort study

Improving hypertension control is an important global health priority yet, to our knowledge, there is no direct evidence on the blood pressure (BP)-mortality relationship in sub-Saharan Africa. We investigate the BP-mortality relationship in South Africa and assess the comparative effectiveness of different care targets for clinical care and population-wide hypertension management efforts. We use country-wide population-based longitudinal data from five waves (2008 - 2017) of the South African National Income Dynamics Study (N = 4,993). We estimate the relationship between systolic BP (SBP) and six-year all-cause mortality and compare the mortality reductions associated with lowering SBP to different targets. We then estimate the number needed to treat to avert one death (NNT) under different hypothetical population-wide scale up scenarios. We found a weak, nonlinear, SBP-mortality relationship with larger incremental mortality benefits at higher SBP values: reducing SBP from 160 to 150 mmHg was associated with a mortality risk ratio of 0.95 (95% CI: 0.90, 0.99, p = 0.033), incrementally reducing SBP from 150 to 140 mmHg a risk ratio of 0.96 (95% CI: 0.91, 1.01, p = 0.12), with no evidence of incremental benefits of reducing BP below 140 mmHg. At the population level, reducing SBP to 150 mmHg among all those with an SBP > 150 mmHg had the lowest NNT (50) at 3.3 deaths averted (95% CI: -0.6, 0.3) per 1,000 population while requiring BP management for 16% (95% CI: 15.2, 17.3) of individuals. The SBP-mortality association is weaker in South Africa than in high-income and many low- and middle-income countries. As such, we do not find compelling evidence in support of targets below 140 mmHg and find that scaling up management based on a 150 mmHg target is more efficient in terms of the NNT compared to strategies to reduce SBP to lower values.