CARDIOVASCULAR JOURNAL OF AFRICA • Vol 24, No 8, September 2013
AFRICA
309
hsCRP level above 3 mg/l and a fibrinogen level above 5 g/l were
accepted as significant.
The study also enrolled patients with atherosclerotic carotid
and/or popliteal artery disease, as defined by the presence of
non-stenotic plaques or carotid stenosis to some degree, who
were clinically asymptomatic or symptomatic at the time of
screening. For a variety of reasons, 135 patients could not finish
the study and were excluded from the study.
Data was collected from the patients between May 2011 and
November 2012. Also excluded from the study were patients
with diabetes mellitus, high cholesterol or triglyceride levels,
hypertension, angina pectoris, a history of myocardial infarction
and stroke, a history of rehabilitation, heart surgery, congestive
heart failure, peripheral vascular disease, alcohol use, active
malignant disease, or any immunological or known chronic
inflammatory condition or were currently smoking. The study
was approved by the institutional review board of the University
of Sifa, and all patients gave signed, written informed consent
before enrollment.
Dental examination
In this study, we used the World Health Organisation-approved
dental indices to quantify dental disease: DMFT as a measure
of dental status and SLI as a measure of oral hygiene and dental
plaque. All dental examinations were performed by specifically
trained dentists blinded to the patients’ clinical and ultrasound
data. Dental examinations took place one week before the
initial ultrasound examination. The oral health parameters of all
subjects were recorded at the beginning of the study.
We evaluated all 28 teeth according to the DMFT index,
excluding the third molar teeth from the study. DMFT used
dental status and the amount of dental caries in an individual to
numerically express the caries prevalence. SLI assessed the state
of oral hygiene and dental plaque accumulation by measuring
both soft and mineralised deposits at four sites per tooth
(mesio-buccal, mid-buccal, disto-buccal and mid-lingual). All
periodontal findings were taken using the half-mouth method at
all four gingival areas of the tooth and marked with a score from
0 to 3. Dental plaque was scored as:
•
0: no plaque
•
1: a film of plaque adhering to the free gingival margin and
adjacent area of the tooth, which can be seen in samples from
the tooth surfaces
•
2: moderate accumulation of soft deposits within the gingival
pocket or the tooth and gingival margin, which can be seen
with the naked eye
•
3: abundance of soft matter within the gingival pocket and/or
the tooth and gingival margin.
In patients who were completely toothless, SLI was obtained
from the prosthesis. SLI of 0 and 1 was defined as absent or mild,
and 2 to 3 as serious.
Carotid B-mode ultrasonography
The carotid and popliteal arterial intima–media thickness and/
or stenosis measurements were performed by experienced
radiologists using B-mode ultrasonography. The extracranial
carotid arteries were examined bilaterally using a 7.5-MHz linear
array transducer (Siemens Antares, Germany). The operators
were blinded to the patients’ clinical data and dental status.
The patients were in a supine position with their heads turned
slightly away from the operator. Measurements were taken in
longitudinal and transverse planes on the common carotid artery
(CCA) far wall, 1 cm from the bulb, the bifurcation, the internal
carotid artery (ICA), external carotid artery (ECA), and popliteal
artery. The intima–media thickness was defined as the distance
between the leading edges of the lumen–intima echo and media–
adventitia echo.
Sub-clinical atherosclerosis was defined as mean carotid
and/or popliteal artery intima–media thickness of more than 1
mm, as assessed by B-mode ultrasound. The 1-mm cut-off point
was chosen because it has clinical and prognostic significance
and has been associated with the subsequent development
of coronary artery disease. Carotid plaque was defined as a
localised intima–media thickening of more than 1 mm, with at
least 100% increase in thickness compared with adjacent wall
segments.
If a plaque occurrence was diagnosed during the examination,
it defined early atherosclerosis. Plaques were present if they
protruded into the lumen or localised roughness with an
increased echogenicity or an area of increased thickness of the
intima–media layer. Plaque presence was defined as one plaque
in any of the carotid arteries. In order to compensate for the
stretching effect of arterial distension secondary to increased
arterial pressure on the wall thickness, the patients’ systolic
arterial pressures were below 140 mmHg.
Statistical analysis
Continuous data are displayed as means with standard deviation.
Categorical data are expressed as proportions. Categorical
variables were analysed using the chi-squared test or Fisher’s
exact test when appropriate. In all studies,
p
<
0.05 were
considered statistically significant.
Results
The two groups of patients had similar baseline demographics
and clinical characteristics. The mean age of the groups was
not significantly different (Table 1). Baseline measurements in
group II of the mean carotid and popliteal artery intima–media
thickness and mean hsCRP levels were significantly higher than
that of group I (
p
=
0. 001). However, there was no correlation
with dental status, oral hygiene and fibrinogen levels (Table 2).
The mean DMFT index scores were 1.1
±
4.56 in group I and
19.82
±
6.44 in group II, while the mean SLI index scores were
0.56
±
2.32 and 2.76
±
3.42, respectively.
Figs 1 and 2 depict carotid artery intima–media thickness
measured in B-mode ultrasonography. This examination revealed
that patients with an intima–media thickness more than 1 mm
numbered 15 (12%) in group I, and 349 (82.12%) in group
II (Table 2). This proportion was 92% in patients who were
toothless.
Increasing DMFT and SLI scores were correlated with
intima–media thickness of the carotid artery. Intima–media
thickness was more than 1 mm in 88% of patients with a DMFT
index higher than 20, and in 69% of patients with an SLI index
of more than 2, but in only 12% of patients with a DMFT index
below 3, and in 6.8% of patients with an SLI score of 0 or 1.
Significantly more patients with an intima–media thickness
greater than 2 mm had a DMFT index more than 20.
