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AFRICA
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CVJAFRICA • Volume 26, No 2, H3Africa Supplement, March/April 2015
billion in the United States, while costs after hospital discharge
were estimated to amount to 2.9 billion Euros in France.
16,70,86,87
Clearly, even a fraction of such amounts can cause enormous
economic damage to low-income countries.
70
There are very few studies on the cost of stroke care in Africa.
A study in Togo estimated direct cost per person of 936 Euros
in only 17 days, about 170 times more than the average annual
heath spend of a Togolese.
88
Subsidising and improving post-
stroke care may help to reduce stroke case fatality rates and
morbidity in Africa.
89
The gaps
Although age-standardised rates of stroke mortality have
decreased worldwide in the past two decades, the absolute
number of people who have a stroke every year, stroke survivors,
related deaths, and the overall global burden of stroke (DALYs
lost) are great and increasing. Further studies are needed to
improve understanding of stroke determinants and burden
worldwide, and to establish causes of disparities, and changes in
trends in stroke burden between countries of different income
levels.
2
In Africa, despite the enormous and growing burden,
numerous gaps have been identified in the required data and
interventions to tame the scourge. For most of the direct
observational studies and models, a time lag of about three
to six years was observed between data collection, analyses
and publication. There is incomplete understanding of the
pattern and determinants of stroke occurrence, type, subtype,
outcome, complications and burden. Furthermore, the incidence,
prevalence, relative risk, and population-attributable risks (PAR)
of genomic and environmental risk factors for stroke among
Africans are not known. Assessment of hypertension and
its risk factors is needed.
90
Accurate population demographic
information essential for determining rates is also needed.
Moreover, causes of disparities and changes in trends of
stroke burden in LMIC/HIC, whites/Africans, as well as the
genomic architecture of stroke among Africans are unknown.
The peculiar genomic, gene–environment and environmental
risk, and protective factors for stroke occurrence, pattern, type,
subtype, outcome and current incidence velocity among people
of African ancestry is unclear. There is also a need for indicators
and determinants of blood pressure levels and dietary intake.
Shaping the future
Projections based on the current trends, incidence velocity, risk-
factor prevalence, population-attributable risks, and relative
risk for risk factors concluded that by 2030, stroke will be the
second leading cause of death globally, the first leading cause of
death in middle-income countries and the third in low-income
countries.
91
The stroke quadrangle is hereby proposed as a holistic
synergy of four pillars aimed at reversing the rising burden.
This approach is consistent with the successful high-impact
interventions implemented in the United States over the past
five decades,
68
as well as the global stroke burden-reduction
objectives from the World Stroke Association
(http://www.world- stroke.org/) and the World Hypertension League
(http://www. worldhypertensionleague.org/), which has resulted in a decline
in stroke burden in high-income countries.
2
It is expected that if
resources are applied efficiently in a similar manner in LMICs,
the burden of stroke will be reduced. These resources include:
•
synergistic epidemiological surveillance and research networks
exploring and monitoring trends in the burden, pattern and
determinants (gene, environment, gene–gene, gene–environ-
ment, transcriptomics, etc) such as the Stroke Investigative
Research and Educational Network (SIREN) project
•
primordial, primary and secondary prevention programmes
at individual, family, systems and community levels, e.g. the
Tailored Hospital-based Risk reduction to Impede Vascular
Events after Stroke (THRIVES) project,
10,92,93
improvement of
stroke literacy and early recognition
•
acute stroke care facilities with rapid evacuation services
•
stroke rehabilitation and recovery services.
Conclusions
In contrast to the declining stroke rates in several developed
countries, the incidence of stroke in Africa, especially
haemorrhagic stroke, has risen substantially over the last 20
years. This rise can only be expected to continue unabated unless
widespread coordinated efforts based on plausible paradigms
that incorporate established and accumulating scientific evidence
are promptly instituted.
The results of this assessment suggest intervention models
such as ‘the stroke quadrangle’ implemented through the SIREN
project may be an effective effort to catalyse risk reduction in
this global high-risk population. SIREN is poised to identify
the unique risk factors (genetic and environmental) associated
with stroke occurrence, type, subtype, pattern and outcome in
black Africans (in Africa and the USA). SIREN is designed to
substantially enhance our understanding of factors that could
be addressed to improve stroke outcomes, and possibly other
vascular disease entities such as coronary artery disease and
chronic kidney disease in people of African ancestry.
Over 3 000 case–control African pairs will be compared
to 1 000 African-Americans and 12 000 white Americans
in the Reasons for Geographic and Racial Differences in
Stroke (REGARDS) study. The study aims to discover/explore
potentially modifiable genetic pathways to stroke risk that may
be common to people of African ancestry.
Key messages
•
Accurate epidemiological data on stroke in Africa is
scanty.
•
However, age-adjusted standardised annual stroke inci-
dence rates may be up to 316 per 100 000, and age-
adjusted standardised prevalence rates may be up to 981
per 100 000.
•
From the Global Burden of Disease model-based esti-
mates, stroke incidence appears to be increasing in Africa.
•
Rigorous comprehensive and prospective epidemiologi-
cal surveillance is urgently needed to assess and monitor
the actual burden and determinants as well as the epide-
miological trend of stroke in Africa.
•
Appropriate intervention paradigms such as the stroke
quadrangle are urgently required.