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VOLUME 11 NUMBER 3 • SEPTEMBER 2014
RESEARCH ARTICLE
SA JOURNAL OF DIABETES & VASCULAR DISEASE
cardiovascular disease who were participants of the Health, Aging,
and Body Composition study (Health ABC study), the presence of
major or minor ECG aberrations at baseline was associated with
coronary heart disease risk during follow up, independent of
classical cardiovascular risk factors.
15
The findings of the Health
ABC study suggest that the presence of ECG aberrations, including
those used to diagnose cardiac ischaemia in our study, should be
given consideration as they may indicate an adverse underlying
cardiovascular risk profile.
Approximately 13% of participants in this study were on a
statin, preventive treatment widely recommended for routine use
in people with diabetes. No correlation was found between statin
use and ECG-diagnosed ischaemic heart disease. This suggests that
the use of statins in this population could be almost doubled by
using ECG criteria to diagnose for ischaemic heart disease. It was
shown in a recent study that the use of recommended preventive
therapies for cardiovascular disease risk reduction, based on global
risk evaluation, was limited in Africa in people with diabetes and
those without.
16
Our study had some limitations. In the absence of follow up, we
were unable to establish any causal relationship between identified
predictors of cardiovascular risk and ECG aberrations. This was a
hospital-based study and therefore included participants who may
not have been typical of those in the community where the majority
of type 2 diabetes persons remain undiagnosed.
17
While this could
have affected the prevalence of ECG changes found in our study,
it was less likely to have affected the direction of associations
described, and therefore would not have invalidated the major
findings from this study.
That ECGs were interpreted by an investigator who was unaware
of the clinical background of the patients, which could have
affected the prevalence of some of the outcomes. Indeed, using
such an approach resulted at best in a description of significant
changes, with no assumption about possible correlations between
coincident aberrations in the same patient.
Our study had somemajor advantages, including the considerable
sample size, which gave us reasonable statistical power to reliably
investigate the parameters. We were also able to investigate the
full spectrum of resting ECG aberrations, which no previous study
has achieved in Africa. The extensive data collection of both clinical
and biological profiles enabled a wide range of predictors to be
investigated for their possible link with prevalent ECG aberrations.
Conclusion
ECG aberrations are frequent in people with diabetes in sub-Saharan
Africa. While some may be benign, others are indicators of serious
underlying conditions or high future risk for cardiovascular disease.
These aberrations have the potential to improve cardiovascular
disease risk stratification and the implementation of preventative
strategies in people with diabetes in sub-Saharan Africa.
The growing prevalence of serious ECG aberrations over time
suggests the need for strategies to monitor such changes and
their determinants, so as to refine the cardiovascular preventative
strategies in sub-Saharan Africa. Elsewhere, dedicated diabetes
registries have successfully served these functions.
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