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CARDIOVASCULAR JOURNAL OF AFRICA • Volume 29, No 6, November/December 2018
344
AFRICA
Prevalence and sociodemographic correlates of
cardiovascular risk factors among patients with
hypertension in South African primary care
JM Ngango, OB Omole
Abstract
Objective:
To determine the prevalence and sociodemographic
correlates of cardiovascular risk factors among patients with
hypertension at Johan Heyns Community Health Centre,
Sedibeng district, South Africa.
Methods:
A total of 328 participants were systematically
sampled. A researcher-administered questionnaire collected
information on: socio-demography, presence of diabetes,
family history of hypercholesterolaemia, family history of
fatal cardiovascular (CV) events, and engagement in physical
activities. Other measurements included: blood pressure (BP),
weight, height, abdominal circumference and electrocardio-
graphy (ECG). Data analysis included descriptive statistics,
chi-squared test and regression analysis. Main outcome
measures included the proportions of participants with each
CV risk and their significant sociodemographic determinants.
Results:
Participants’ mean age was 57.7 years. Most partici-
pants were black (86.0%), female (79%) and pensioners
(43.6%). The mean BP was 139/84 mmHg, and 60.7% had
their BP controlled to targets. There was an average of 3.7
CV risk factors per participant and the prevalence of CV risk
factors was: abdominal obesity (80.8%), physical inactivity
(73.2%), diabetes (30.2%), alcohol use (28.0%), hypercho-
lesterolaemia (26.5%), smoking (11.9%), past family history
of fatal CV event (14.9%), and left ventricular hypertrophy
(5.2%). Sociodemographic factors significantly associated
with each CV risk factor were: obesity and being female (
p
=
0.00); alcohol use and young age (
p
=
0.00); smoking, being
male and race other than black (
p
=
0.00 and
p
=
0.00, respec-
tively); physical inactivity, being a pensioner and male (
p
=
0.02 and
p
=
0.02, respectively); diabetes and being male (
p
=
0.03); hypercholesterolaemia and race other than black (
p
=
0.03); family history of hypercholesterolaemia and race other
than black (
p
=
0.00); and family history of fatal CV event and
race other than black (
p
=
0.00).
Conclusion:
There is a high burden of CV risk factors among
patients with hypertension in South African primary care,
signifying a substantial risk of cardiovascular disease (CVD)
in this setting. Interventions aimed at CVD risk reduction
need to take cognisance of the sociodemographic correlates
of CV risk factors.
Keywords:
prevalence, cardiovascular risk factors, hypertension,
primary care
Submitted 5/5/17, accepted 24/6/18
Cardiovasc J Afr
2018;
29
: 344–351
www.cvja.co.zaDOI: 10.5830/CVJA-2018-038
Hypertension is a major risk factor for cardiovascular disease
(CVD).
1
It affects a quarter of the world’s adult population and
accounts for 80% of deaths and 87% of disability in developing
countries.
2,3
Its burden is greater in low- and middle-income than
in high-income countries.
4
In the past four decades, African countries have experienced
an increased prevalence of CVD due to increasing urbanisation
and lifestyle changes.
5
CVD is the second leading cause of
mortality after HIV/AIDS in South Africa, accounting for up to
40% of deaths among adults.
6
In South Africa, of all CVD risk factors, hypertension is the
commonest, with a prevalence that is highest among the poor
in urban settings.
7,8
Hypertension often co-exists with other CV
risk factors, resulting in a significantly increased risk for CVD.
9
Of serious concern is that the prevalence of these other CV risk
factors, such as diabetes, tobacco use, high cholesterol levels,
obesity, physical inactivity and unhealthy diets are also on the
increase, both in urban and rural settings in Africa.
10
Most CV risk factors are modifiable, providing opportunities
for reduction in CVD-attributable morbidity and mortality
rates.
11
Simultaneously addressing CV risk factors substantially
reduces the risk of adverse CV events more than controlling for
any single risk factor alone.
12
In this vein, it is well established
that lowering only blood pressure (BP) does not adequately
minimise the risk of CV morbidity and mortality. Despite this
knowledge, co-existing CV risk factors remain inadequately
managed among patients with hypertension.
9
In South Africa, clinicians at the primary healthcare
(PHC) level manage a substantial proportion of patients with
hypertension. This level of care is expected to provide primary and
secondary prevention interventions through patient education
on healthy lifestyle, screening, and prompt management of
CV risk factors. To carry out these tasks effectively for patients
with hypertension, it is important to know which of the CV
risk factors are prevalent in a PHC setting, especially since the
burden of CV risks may differ across populations.
13
Patients with
hypertension in health facilities have a higher baseline CV risk
burden than reported in community-based studies.
Although the South African literature has reported urban–
rural disparity and higher-than-expected CV risk prevalence in
the general population,
14
few studies have focused on patients
with hypertension in PHC facilities. The aim of this study was
to determine the prevalence and determinants of CV risk factors
among patients with hypertension in a large, peri-urban PHC
facility in Gauteng province, South Africa.
Division of Family Medicine, Department of Family
Medicine, University of the Witwatersrand, Johannesburg,
South Africa
JM Ngango, MD, HDip Surg (SA),
drngango@gmail.comOB Omole, MB BS, DA, MCFP (SA), MMed (Fam Med)