Mortality transition over a quarter century in rural South Africa: findings from population surveillance in Agincourt 1993-2018

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ABSTRACT

Background

Mortality burden in South Africa since the mid-1990s has been characterized by a quadruple disease burden: HIV/AIDS and tuberculosis (TB); other communicable diseases (excluding HIV/AIDS and TB), maternal causes, perinatal conditions and nutritional deficiencies; non-communicable diseases (NCDs); and injuries. Causes from these broad groupings have persistently constituted the top 10 causes of death. However, proportions and rankings have varied over time, alongside overall mortality levels.

Objective

To provide evidence on the contributions of age and cause-of-death to changes in mortality levels in a rural South African population over a quarter century (1993–2018).

Methods

Using mortality and cause-of-death data from the Agincourt Health and Socio-Demographic Surveillance System (HDSS), we derive estimates of the distribution of deaths by cause, and hazards of death by age, sex, and time period, 1993–2018. We derive estimates of life expectancies at birth and years of life expectancy gained at age 15 if most common causes of death were deleted. We compare mortality indicators and cause-of-death trends from the Agincourt HDSS with South African national indicators generated from publicly available datasets.

Results

Mortality and cause-of-death transition reveals that overall mortality levels have returned to pre-HIV epidemic levels. In recent years, the concentration of mortality has shifted towards older ages, and the mortality burden from cardiovascular diseases and other chronic NCDs are more prominent as people living with HIV/AIDS access ART and live longer. Changes in life expectancy at birth, distribution of deaths by age, and major cause-of-death categories in the Agincourt population follow a similar pattern to the South African population.

Conclusion

The Agincourt HDSS provides critical information about general mortality, cause-of-death, and age patterns in rural South Africa. Realigning and strengthening the South African public health and healthcare systems is needed to concurrently cater for the prevention, control, and treatment of multiple disease conditions.

KEYWORDS:

• South Africa
• mortality
• verbal autopsy
• non- communicable diseases (NCDs)
• health and socio-demographic surveillance system (HDSS)

Responsible Editor

Stig Wall

Responsible Editor

Stig Wall

Acknowledgments

This study would not have been possible without the valuable contributions of respondents, field staff and management of the MRC/Wits Rural Public Health and Health Transitions Research Unit (Agincourt).

Author contributions

CWK and KK conceived the study. CWK analyzed the data with the support of BH. CWK wrote the first draft of the manuscript. All authors reviewed the manuscript and approved it for submission.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Ethics and consent

Ethical clearance for surveillance activities in the Agincourt HDSS was obtained from the Human Research Ethics Committee (Medical) of the University of the Witwatersrand (protocols M960720, M110138 and M180585). Community consent was obtained from civic and traditional leadership at the start of surveillance in 1992 and is reaffirmed from time to time. In addition, informed verbal consent is obtained from the head of the household or an eligible adult in the household at each annual follow-up surveillance visit. The consent process is documented by marking out the respondent on the household roster and recording details of the responsible fieldworker and date.

Availability of data and material

Detailed documentation describing the Agincourt HDSS data and an anonymized database containing data from 10% of the surveillance households are available for public access on the MRC/Wits Rural Public Health and Health Transitions Research Unit (Agincourt)’s data repository [62]. The Agincourt HDSS core demographic data are also routinely deposited for public access in the INDEPTH Network Data Repository [63] and SAPRIN data repository [64]. The customized data used in this study will be made available on request to interested researchers.

Paper context

South Africa is experiencing a protracted transition in mortality levels and causes of death, with multiple stages overlapping and changes incomplete. This requires continuous monitoring in order to advise policy-makers on health planning and resource allocation. Using health and socio-demographic surveillance data, this paper provides evidence on the contributions of age and various causes of death to changes in mortality levels in a rural population in northeast South Africa over a quarter century, 1993–2018.

Additional information

Funding

The ongoing Agincourt Health and socio-Demographic Surveillance System has been enabled with funding from the South African Department of Science and Innovation through the South African Population Research Infrastructure Network (SAPRIN) which is hosted by the South African Medical Research Council; the South African Medical Research Council; the University of the Witwatersrand, and previously the Wellcome Trust, UK (grants 058893/Z/99/A, 069683/Z/02/Z, 085477/Z/08/Z, and 085477/B/08/Z)