Page 233 - Special Topic Session (STS) - Volume 2

STS489 Glory A. et al.

Geographic variation, trends and determinants of
hypertension in South African adult population,
2008 -2017
1
1
3
Glory Atilola , Ngianga-Bakwin Kandala 1,2 , Guangquan Li ; Samuel Manda
1 Northumbria University, Department of Mathematics, Physics and Electrical Engineering,
Faculty of Engineering and Environment, Newcastle upon Tyne, NE1 8ST, United Kingdom
2 University of the Witwatersrand, Division of Epidemiology and Biostatistics, School of Public
Health, Johannesburg, South Africa
3 Biostatistics Research Unit, South African Medical Research Council, Pretoria South Africa

Abstract
The burden of hypertension in Sub-Saharan Africa in the past two decades has
become a serious cause for regional concern. High blood pressure is the most
powerful predictor of stroke and other cardiovascular outcomes in the region.
An estimated 11.1% rise in regional burden was reported between 1990 and
2010 along with a projected increase of 216.8 million affected individuals by
2030 from 130.2 million in 2010 across the region especially in South Africa. In
this study, we investigate hotspots, temporal trends and determinants of
prevalent hypertension in South African adult population between 2008 and
2017. We utilized spatial and spatio-temporal structured geo-additive
regression models to map hotspots, and temporal trends of hypertension in
South African adult population between 2008 and 2017. Known individual risk
factors were controlled for. Analysis was conducted for four consecutive
national income dynamics household surveys. Implementation was carried out
within Bayesian framework using MCMC simulation methods. An overall
absolute decline of 6% point and a relative decline of 24% in the prevalence
of hypertension were found at the national level between 2012 and 2017.
Hotspots exist across districts in Western Cape and Eastern Cape while districts
in Limpopo province had considerably low risk of hypertension. This pattern
of geographic variation in risk was consistently observed over the four
consecutive time points between 2008 and 2017. Controlling for known
individual risk factors explained a substantial amount of geographic variation
in risk over time except in RSM in North West, Uthukela and Ugu districts in
Kwazulu-Natal where average risk of hypertension remained high. Risk factors
of hypertension in South African adult population include age, coloured
population group, education, lack of exercise and diabetes. Study findings
demonstrate evidence that South Africa is making progress towards the
national 2020 target of 25% reduction in prevalent hypertension at the
national level. However, considerable variation in risk exists across the districts.
Cost-effective policy responses to the emerging trends in cardiovascular
disease burden across the region depend on accurate estimates of distribution
and determinants of cardiovascular health outcomes at both national and

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