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VOLUME 13 NUMBER 2 • DECEMBER 2016
REVIEW
SA JOURNAL OF DIABETES & VASCULAR DISEASE
Epidemiology of ischaemic heart disease in sub-Saharan
Africa
CHURCHILL LUKWIYA ONEN
Correspondence to: Churchill Lukwiya Onen
Centre for Chronic Diseases, Gaborone, Botswana
E-mail:
onenkede@info.bwPreviously published in
Cardiovasc J Afr
2013;
24
: 34–42
S Afr J Diabetes Vasc Dis
2015;
13
: 88–96
Abstract
Background:
The epidemiology of ischaemic heart disease
(IHD) in sub-Saharan Africa (SSA) remains largely enigmatic.
Major obstacles to our understanding of the condition include
lack of reliable health statistics, particularly cause, specific
mortality data, inadequate diagnostic capabilities, shortage
of physicians and cardiologists, and misguided opinions.
Methods:
This review of the epidemiology of ischaemic
heart disease in sub-Saharan Africa involved a systematic
bibliographicMEDLINE search of published data on IHD in SSA
over the past century. Search words included epidemiology,
ischaemic (coronary) heart disease, myocardial infarction,
cardiovascular risk factors and sub-Saharan Africa. Selected
data are presented on the prevalence of cardiovascular risk
factors and mortality from ischaemic heart disease from
different countries representing the main regions of the
continent.
Results:
Although IHD in SSA remains relatively uncommon,
its prevalence is predicted to rise in the next two decades
due to the rising prevalence of risk factors, especially
hypertension, diabetes, overweight and obesity, physical
inactivity, increased tobacco use and dyslipidaemia. It is
estimated that age-standardised mortality rates for IHD will
rise by 27% in African men and 25% in women by 2015, and
by 70 and 74%, respectively by 2030.
Conclusion:
Ischaemic heart disease remains relatively
uncommon in SSA, despite an increasing prevalence of risk
factors, but its incidence is rising. The pace and direction of
economic development, rates of urbanisation, and changes in
life expectancy resulting from the impact of pre-transitional
diseases and violence will be major determinants of the
IHD epidemic in SSA. The best window of opportunity for
prevention of the emerging epidemic of ischaemic heart
disease in sub-Saharan Africa is now.
Keywords:
epidemiology, ischaemic heart disease, sub-Saharan
Africa
‘a riddle wrapped in a mystery inside an enigma’
1 October, 1939
Sir Winston Churchill, British orator, author and Prime Minister
(1874–1965)
Over a century ago, Sir Winston Churchill, a renowned British
statesman and leader during the Second World War (WWII), made
a celebrated visit to Uganda, where he was so moved as to describe
it as ‘the Pearl of Africa’. Sir Winston, referring to the quality of
intelligence gathered by Western allies during WWII, called Russia a
‘riddle wrapped in a mystery inside an enigma’.
While the same phrase could be used today to describe the
epidemiology of ischaemic heart disease (IHD) in sub-Saharan
Africa (SSA) because of many puzzles and lingering myths, what is
enigmatic is the contempt with which the potential threat of IHD
has been treated at various levels of health sectors, governments
and international agencies. A recent change in posture by World
Health Organisation (WHO) Regional Office for Africa, with greater
focus on non-communicable disease (NCD), and the United Nations
high-level meeting on NCD prevention and control in New York on
19–20 September 2011 are good indicators of the recognition of
the importance of NCDs and the rapidly unfolding epidemiological
landscape catalysed by the birth of conjoined twins, infectious
diseases and non-communicable diseases.
The 30th anniversary of the Pan-African Society of Cardiology
(PASCAR) conference along with the Third All-Africa Conference on
Heart Disease, Diabetes and Stroke took place at Munyonyo Speke
Resort in Kampala on the shores of Lake Victoria in May 2011. The
warmth of the land, the gentle tropical rain showers interspersed
with bright sunshine, and above all, the friendliness of Ugandans
must have pervaded the hearts of most foreign delegates to the
conference.
This review article will focus on some of the obstacles to our
understanding of IHD in SSA. A synopsis of cardiovascular risk
factors and their role in IHD in SSA, and selected mortality data
on IHD from various countries across the continent are presented
in this article. A plea for urgent and concerted action to avert the
impending epidemic of IHD in SSA is made.
Obstacles to our understanding of IHD in SSA
Major obstacles to our understanding of IHD in SSA include lack of
reliable statistics on health, life expectancy and disease incidence,
and the absence of cause-specific mortality data. This is confounded
by lack of diagnostic capabilities in most of SSA, emanating from
a shortage of physicians, particularly cardiologists, and lack of
appropriateinvestigations,suchasresting12-leadelectrocardiographs
(ECGs), exercise ECGs, cardiac biomarkers (troponins, CKMB) and
cardiac imaging such as echocardiography, coronary angiography,
computed tomography (CT) angiography, intravascular ultrasound
scans (IVUS) and radionuclide myocardial perfusion studies.
Resting 12-lead ECGs, although generally more widely available
and relatively inexpensive, have limited sensitivity and specificity
for the diagnosis of acute coronary syndromes. Furthermore, there
are high rates of non-specific ST-segment and T-wave changes
suggestive of myocardial ischaemia in up to 10% of asymptomatic
African men and 20% of women over the age of 40 years.
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