53 / 76
CARDIOVASCULAR JOURNAL OF AFRICA • Volume 29, No 3, May/June 2018
AFRICA
183
Association of traditional cardiovascular risk factors
with carotid atherosclerosis among adults at a teaching
hospital in south-western Nigeria
Adeleye Dorcas Omisore, Olusola Comfort Famurewa, Morenikeji Adeyoyin Komolafe, Christiana
Mopelola Asaleye, Michael Bimbola Fawale, Babalola Ishmael Afolabi
Abstract
Background:
Traditional cardiovascular risk factors (CVRFs),
which include age, gender, hypertension, diabetes melli-
tus, dyslipidaemia, smoking, alcohol consumption, chronic
kidney disease and obesity, have been shown to be associ-
ated with atherosclerosis. We aimed to evaluate the impact
of traditional CVRFs on carotid atherosclerosis (CA) in a
sample of Nigerian adults.
Methods:
We examined 162 subjects with traditional CVRFs
in a cross-sectional study. Demographic and clinical data,
including history of hypertension, diabetes mellitus, smok-
ing, alcohol intake and chronic kidney disease, as well as
systolic and diastolic blood pressure, weight and height were
collected. Serum creatinine, fasting blood glucose and lipid
profiles were also determined. Carotid intima–media thick-
ness (CIMT) and presence of carotid plaque (CP) were evalu-
ated by high-frequency B-mode ultrasound. Chi-squared and
regression analyses were carried out to determine associations
between variables of CIMT and CVRF.
Results:
Increased CIMT was associated with all CVRFs (
p
<
0.05) except gender (
p
>
0.05), while CP was associated
with older age, obesity, hypertension and dyslipidaemia (
p
<
0.05). We found prevalence of increased CIMT was 53.7%,
while that of CP was 16.1%. The prevalence of CA (increased
CIMT and CP) also increased with increasing number
of CVRFs in the subjects. Age
≥
50 years, hypertension,
dyslipidaemia, obesity and alcohol intake explained 78.7%
of variance in CIMT, while age
≥
50 years and hypertension
explained 38.0% of variance in CP.
Conclusions:
CA was associated with presence and increas-
ing number of traditional CVRFs. A significant percentage
of variance in CA was, however, unexplained by traditional
CVRFs.
Keywords:
atherosclerosis, cardiovascular, carotid, Nigerian, risk
factors
Submitted 1/8/16, accepted 19/2/18
Published online 28/2/18
Cardiovasc J Afr
2018;
29
: 183–188
www.cvja.co.zaDOI: 10.5830/CVJA-2018-014
Atherosclerosis is the primary cause of morbidity and mortality
in cardiovascular disease.
1
It develops silently over decades,
long before symptoms occur.
1
Carotid intima–media thickness
(CIMT) is a measure of subclinical atherosclerosis associated
with cardiovascular risk factors (CVRFs) and is predictive
of cardiovascular diseases such as myocardial infarction and
stroke.
2
Conventionally, CVRFs are divided into traditional
and non-traditional factors.
3
Traditional CVRFs, including
age, gender, obesity, diet, hypertension, diabetes mellitus,
dyslipidaemia, smoking, alcohol consumption and chronic kidney
disease have been shown to account for most of the population-
attributable risks for cardiovascular events.
3-5
Existing evidence
suggests an association between these individual traditional
CVRFs and CIMT.
6
Studies have gone further to establish the
greater impact of multiple risk factors on CIMT compared
with individual risk factors in different population groups.
6,7
Traditional CVRFs, however, account for
<
50% of the variance
of atherosclerotic plaque burden and may not explain a large
proportion of the variance in CIMT, especially when measured
in plaque-free locations.
8
Intima–media thickness is widely accepted as a valid
marker for the process of atherosclerosis and has been applied
in the study of cardiovascular disease for more than two
decades.
1
Carotid ultrasonography is a non-invasive means of
identifying early-stage atherosclerotic changes in the arterial
wall with the measurement of intima–media thickness and
detection of plaque.
1
Combined CIMT and plaque assessment is
considered better than either measure alone in the assessment of
atherosclerotic risk.
9
Early detection of predictors of CIMT and their early
modification may have a significant impact on the prevention
of atherosclerotic disease.
1
Therefore, to reduce the mortality
rate associated with cardiovascular diseases such as stroke,
it is clinically important to study the effects of CVRFs on
carotid atherosclerosis. In this study, we aimed to evaluate the
association of individual traditional CVRFs and the cumulative
effect of multiple CVRFs with carotid atherosclerosis (CA) in a
sample of Nigerian adults with established CVRFs.
Department of Radiology, Obafemi Awolowo University and
Obafemi Awolowo University teaching hospitals complex,
Ile-Ife, Nigeria
Adeleye Dorcas Omisore, MB BS, FWACS, FMCR, omisoreadel-
eye@yahoo.comOlusola Comfort Famurewa, MB ChB, FWACS
Christiana Mopelola Asaleye, MB ChB, FWACS
Department of Medicine, Obafemi Awolowo University,
Ile-Ife, Nigeria
Morenikeji Adeyoyin Komolafe, MB BS, FWACP
Michael Bimbola Fawale, MB BS, MSc, FMCP
Department of Radiology, Obafemi Awolowo University
teaching hospitals complex, Ile-Ife, Nigeria
Babalola Ishmael Afolabi, MB ChB, FWACS, FMCR