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RESEARCH ARTICLE
SA JOURNAL OF DIABETES & VASCULAR DISEASE
8
VOLUME 15 NUMBER 1 • JULY 2018
Cardiovascular disease risk assessment in Nigerian adults
with type 2 diabetes or the metabolic syndrome, using the
Framingham risk score
Ifeoma Christiana Udenze, Casmir Ezenwa Amadi
Correspondence to: Ifeoma Christiana Udenze
Department of Clinical Pathology, College of Medicine, University of Lagos,
Nigeria
e-mail:
kristyudenze@ymail.comCasmir Ezenwa Amadi
Department of Medicine, Cardiology Unit, College of Medicine, University
of Lagos, Nigeria
S Afr J Diabetes Vasc Dis
2018;
15
: 8–12
Abstract
Background:
Cardiovascular morbidity is a major burden
in Nigerian patients with type 2 diabetes mellitus (DM).
Predicting and quantifying cardiovascular risk could help in
more focused and aggressive management of type 2 DM and
its cardiovascular complications.
Aim:
The aim of this study was to compare the cardiovascular
risk scores of type 2 diabetes subjects on treatment with those
of individuals with the metabolic syndrome, and healthy
controls, and to examine the impact of glycaemic control and
lifestyle on cardiovascular risk in adult Nigerians
Methods:
This was a cross-sectional study of 40 adult men and
women with type 2 diabetes attending the Diabetic Clinic,
40 adult men and women with the metabolic syndrome,
and 40 age- and gender-matched males and females,
who were recruited as healthy controls. The metabolic
syndrome was defined based on the NCEP-ATP III criteria.
Socio-demographic and clinical data were collected using a
structured questionnaire. Venous blood was collected after
an overnight fast.
Results:
There was a statistically significant difference in the
cardiovascular risk scores between the group with diabetes
(20.41 ± 12.98), the group with the metabolic syndrome
(10.00 ± 6.35), and the control group (6.79 ± 7.81) (
p
< 0.001).
There was also a statistically significant difference in the
glycated haemoglobin (HbA
1c
),
high-density lipoprotein
cholesterol, total cholesterol and triglyceride concentrations
between the three study groups (
p
< 0.05). Cardiovascular
risk correlated positively and significantly with HbA
1c
level,
body mass index and waist circumference, and negatively
with education level (
p
< 0.05). Only 52.2% of the diabetics
on treatment achieved an HbA
1c
target of < 7%.
Conclusion:
Type 2 diabetes patients on treatment had high
cardiovascular risk scores, and control of cardiovascular risk
factors was not optimal in adult Nigerians, especially in
individuals with type 2 diabetes or the metabolic syndrome.
Strategies to achieve better glycaemic control, weight
reduction and increased literacy levels would help achieve
cardiovascular risk reduction in adult Nigerians.
Keywords:
cardiovascular disease risk score, type 2 diabetes,
metabolic syndrome, Framingham study
Introduction
The prevalence of type 2 diabetes is increasing globally and
factors such as aging of the population, increasing prevalence of
obesity and sedentary lifestyles have contributed to this trend.
1,2
In 2009, global estimates put the world prevalence of diabetes
among adults at 6.4%, affecting 285 million adults in 2010, and
projected to increase to 7.7%, affecting 439 million adults by
2030.
3
There was also an estimated 69% increase in numbers of
adults with type 2 diabetes in developing countries, compared to
a 20% increase in developed countries between 2010 and 2015.
3
In Nigeria, the estimated prevalence rate for type 2 diabetes was
4.3% and over five million people are projected to be affected
by 2030.
3
Diabetes is an independent risk factor for cardiovascular disease
(CVD).
4,5
Type 2 diabetes is associated with a two- to four-fold
increase in the risk of both coronary heart disease and stroke.
6,7
CVDs are listed as the cause of death in approximately 65% of
persons with diabetes,
8
and strategies to reduce CVD risk is an
important part of the management protocol for type 2 diabetes.
9
Quantifying the risk of developing CVD in patients with diabetes
has important strategic benefits in patient management.
10-12
CVD
risk quantification is useful in ranking individuals and groups
according to absolute risk for the purpose of targeting therapy to
those at greatest risk in order to appropriately allocate community
and health resources.
11
It also provides prognostic information or
accurate estimations of the likely absolute benefit from a therapeutic
intervention.
11,12
In addition to being part of a preventative strategy
to motivate patients to change their behaviour and adhere to
medical treatments,
10
CVD risk quantification can also be an
assessment tool for clinicians to examine the effectiveness of their
therapeutic interventions.
Todays’ lifestyle choices are characterised by increased physical
inactivity and the consumption of calorie-dense foods, which fuel
the obesity pandemic. Obesity and physical inactivity have been
implicated in the development of insulin resistance in individuals
who are genetically susceptible.
1,13
Insulin resistance is the first defect
in a cascade of metabolic abnormalities leading up to the onset of
type 2 diabetes. These dysmetabolic features include cardiovascular
risk factors such as dyslipidaemia, hypertension, inflammatory and
prothrombotic factors.
14
The clustering of these risk factors in a single individual is termed
the metabolic syndrome. The metabolic syndrome commonly
precedes the development of type 2 diabetes by many years,
15
and is
also an independent risk factor for CVD. Therefore, early detection
of the risk factors associated with the metabolic syndrome is