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CARDIOVASCULAR JOURNAL OF AFRICA • Volume 28, No 2, March/April 2017
AFRICA
125
Review Article
The integrated effect of moderate exercise on coronary
heart disease
Marc J Mathews, Edward H Mathews, George E Mathews
Abstract
Background:
Moderate exercise is associated with a lower
risk for coronary heart disease (CHD). A suitable integrated
model of the CHD pathogenetic pathways relevant to moder-
ate exercise may help to elucidate this association. Such a
model is currently not available in the literature.
Methods:
An integrated model of CHD was developed and
used to investigate pathogenetic pathways of importance
between exercise and CHD. Using biomarker relative-risk
data, the pathogenetic effects are representable as measurable
effects based on changes in biomarkers.
Results:
The integrated model provides insight into higher-
order interactions underlying the associations between CHD
and moderate exercise. A novel ‘connection graph’ was devel-
oped, which simplifies these interactions. It quantitatively
illustrates the relationship between moderate exercise and
various serological biomarkers of CHD. The connection
graph of moderate exercise elucidates all the possible inte-
grated actions through which risk reduction may occur.
Conclusion:
An integrated model of CHD provides a summa-
ry of the effects of moderate exercise on CHD. It also shows
the importance of each CHD pathway that moderate exercise
influences. The CHD risk-reducing effects of exercise appear
to be primarily driven by decreased inflammation and altered
metabolism.
Keywords:
moderate exercise, biomarkers, integrated model
Submitted 11/9/15, accepted 5/5/16
Published online 12/12/16
Cardiovasc J Afr
2017;
28
: 125–133
www.cvja.co.zaDOI: 10.5830/CVJA-2016-058
Coronary heart disease (CHD) is known to be the major
cause of death globally.
1
However, it is well documented that
regular moderate physical exercise is associated with fewer
CHD events in symptomatic
2
and asymptomatic
3,4
subjects.
The precise mechanisms underlying this inverse association
are unclear. However, it is apparent that CHD risk may be
substantially mediated, through moderate exercise, by changes
in blood pressure, insulin resistance and glucose intolerance,
systemic inflammation, triglyceride concentrations, low high-
density lipoprotein (HDL) levels and obesity.
4,5
It may therefore prove beneficial to quantify and elucidate
the underlying pathogenetic effect of moderate exercise on the
pathogenesis of CHD. Using a previously described integrated
model of CHD,
6,7
we investigated the interconnectivity of
moderate exercise and the pathogenesis and pathophysiological
attributed to CHD.
Methods
An integrated model was developed as part of a larger research
project.
6
This project has partially been described in previous
articles dealing with certain subsets of the research.
7-9
Briefly,
a systematic review of the literature post-1998 and including
highly cited articles was conducted for CHD pathogenesis,
health factors, biomarkers and pharmacotherapeutics. This
research was combined to develop the integrated model of CHD.
During the systematic literature review, PubMed, Science
Direct, Ebsco Host and Google Scholar were searched for
publications with ‘coronary heart disease’ or ‘coronary artery
disease’ or ‘cardiovascular disease’ or ‘CHD’ as a keyword and
combinations with ‘lifestyle effects’, ‘relative risk prediction’,
‘network analysis’, ‘pathway analysis’, ‘interconnections’,
‘systems biology’, ‘pathogenesis’, ‘biomarkers’, ‘conventional
biomarkers’, ‘drugs’, ‘therapeutics’, ‘pharmacotherapeutics’,
‘hypercoagulability’, ‘hypercholesterolaemia’, ‘hyperglycaemia’,
‘hyperinsulinaemia’, ‘inflammation’ and ‘hypertension’ in the
title of the study.
Also searched were all major relevant speciality journals
in the areas of cardiology, alcohol consumption, nutrition,
cigarette smoking, physical exercise, oral health, psychological
stress, depression, sleep disorders, endocrinology, psychoneuro-
endocrinology, systems biology, physiology, periodontology,
CHD, the metabolic syndrome and diabetes.
The health factors in the integrated model were considered
as lifestyle effects or co-morbid health disorders that have been
associated with statistically significant increases or decreases in
CHD risk. This resulted in nine health factors being considered
in the model, namely alcohol, food, exercise, smoking, oral
health, stress, depression, insomnia and sleep apnoea.
The biomarkers considered for the integrated model were
mainly those whose measurement has been associated with
statistically significant increases or decreases in CHD risk.
Centre for Research and Continued Engineering Development,
North-West University, Potchefstroom, South Africa
Marc J Mathews, PhD
Edward H Mathews, PhD
George E Mathews,
20270046@nwu.ac.za