CARDIOVASCULAR JOURNAL OF AFRICA • Vol 22, No 5, September/October 2011
266
AFRICA
does not achieve BP control in the majority of hypertensives.
Importantly however, 76% of treated hypertensives had BP
levels
<
159/99 mmHg, and therefore, to achieve BP control in
all treated hypertensives may not require a considerable increase
in drug therapy.
Due to the high prevalence of obesity, a limitation of the
present study was our inability to appropriately assess target-
organ changes from electrocardiography. This could therefore
have resulted in us underestimating the extent of cardiovascular
risk in the untreated hypertensives and hence would have biased
against the outcomes of the study. In a sub-study conducted with
echocardiography and electrocardiography, we are presently
attempting to identify the most effective electrocardiographic
criteria that may be employed to identify left ventricular hyper-
trophy in obese individuals of African ancestry. In addition,
because we had no method of validating the answers of questions
related to adherence to antihypertensive therapy, our study was
limited in that we were unable to identify reasons for a lack of
effective treatment in the hypertensives. However, notwithstand-
ing the importance of such a question, this was not the primary
aim of our study.
Conclusion
In urban, developing communities of African ancestry, 6.7%
of people may have untreated hypertension together with an
overall cardiovascular risk profile that requires drug therapy.
This could translate, over 10 years, into 1 740 cardiovascular
events per 100 000 of the population of African ancestry living in
urban, developing communities in South Africa, due to a lack of
antihypertensive drug therapy. This clearly represents a consid-
erable health burden that can only be rectified by introducing
programmes at a community level to identify hypertensives that
require drug therapy. In this regard, the majority of these indi-
viduals had a high risk because of either the presence of severe
hypertension or DM.
This study was supported by the Medical Research Council of South Africa,
the University Research Council of the University of the Witwatersrand,
the National Research Foundation (focus areas: Women in Research and
the Thuthuka Program), the Circulatory Disorders Research Trust, the
Hypertension Society of Southern Africa, and the Carnegie Corporation.
This study would not have been possible without the voluntary collabora-
tion of the participants and the excellent technical assistance of Mthuthuzeli
Kiviet and Nkele Maseko.
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