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CARDIOVASCULAR JOURNAL OF AFRICA • Volume 28, No 5, September/October 2017
316
AFRICA
Every subject had a 12-lead surface ECG, using a long-lead V1
complex as a rhythm strip with three-channel automated Schiller
ECG machine (Switzerland) AT-1. Other investigations done
were standard postero-anterior chest X-rays for detecting occult
cardiopulmonary lesions and for estimating cardiothoracic ratio
(CTR), serum urea, creatinine, electrolyte and calcium levels, and
CD4 (clusters of differentiation 4) cell count.
Statistical analysis
The data were analysed using SPSS version 15.0. Descriptive
statistics were used to determine the mean values of the
variables and the median value of the CD4 cell counts in the
study population. Chi-squared analysis was used for testing for
significant differences between proportions and frequencies,
while the Student’s
t
-test was used to compare continuous
variables between the treatment-naïve HIV-positive patients and
HIV-negative controls. A
p-
value
<
0.05 was taken as statistically
significant.
Results
Out of 250 treatment-naïve HIV-positive subjects studied, 124
(49.6%) were female and 126 (50.4%) were male. Out of 200
HIV-negative control subjects, 107 (53.5%) were female and 93
(46.5%) were male.
The HIV-positive subjects comprised Igbo 232 (92.6%),
Hausa seven (3.1%), Igala five (2.0%) and other groups six
(2.3%). By contrast, the HIV-negative control subjects were
made up of Igbo 178 (89.0%), Hausa six (2.9%), Igala six (2.9%)
and other groups 10 (5.2%). The majority of the study subjects
(94.5%) was Christian.
All the subjects were in the age range of 15–60 years. The
mean age of the treatment-naïve HIV-positive subjects was 34.89
±
10.58 years and the controls was 36.04
±
12.61 years. There was
no significant difference between the ages of the two groups (
p
=
0.146).
Table 1 shows the descriptive statistics of the study subjects.
The mean BMI, SBP and DBP were significantly lower in the
treatment-naïve HIV-positive subjects than in the HIV-negative
control subjects. Most (70%) of the HIV-positive subjects had a
BMI
<
18.5 kg/m
2
(underweight). The mean body temperature
was significantly higher in the HIV-positive subjects than in the
HIV-negative subjects.
The mean serum albumin level (22.14 g/l) was low in the
treatment-naïve HIV-positive subjects (Table 2). Low CD4 cell
counts (
<
200 cells/ml) were present in 75 (30%) of HIV-positive
subjects.
All the subjects, both treatment-naïve and HIV-negative, had
normal cardiac apex and normal chest X-rays.
An abnormal ECG was present in 175 (70%) of the 250
treatment-naïve HIV-positive subjects, and 70 (35%) of the
200 HIV-negative subjects. Table 3 shows the various ECG
abnormalities in the study population. Sinus tachycardia was
present in 160 (64%) of the HIV-positive subjects, prolonged
QTC in 120 (48%), ST depression in 75 (30%) and T-wave
inversion in 54 (21.6%). Table 3 shows all the ECG abnormalities.
Comparison of the mean ECG parameters between the
study groups is shown in Table 4. The mean heart rate, axis,
PR interval and QTC were significantly higher in treatment-
naïve HIV-positive subjects than in the HIV-negative subjects.
Conversely, the mean QRS duration did not differ significantly
between the two groups. All the subjects in the study were in
sinus rhythm.
Out of the 250 HIV-positive patients, 160 (64.0%) had
tachycardia, while 24 (12.0%) of the 200 HIV-negative subjects
had tachycardia. This difference was statistically significant (
p
Table 1. Descriptive statistics of the study and control groups
Parameters
Group Sample size Mean
SD
p
-value
Age (years)
HIV+
HIV–
250
200
34.89
36.04
10.58
12.61
0.146
BMI (kg/m
2
)
HIV+
HIV–
250
200
20.05
22.77
1.522
2.663
<
0.001
Sitting SBP (mmHg)
HIV+
HIV–
250
200
104.2
119.1
10.27
9.97
<
0.001
Sitting DBP (mmHg)
HIV+
HIV–
250
200
76.6
76.9
4.747
4.637
0.848
Standing SBP (mmHg) HIV+
HIV–
250
200
98.96
115.0
10.63
5.84
<
0.001
Standing DBP (mmHg) HIV+
HIV–
250
200
77.64
75.25
5.267
5.203
<
0.001
Temperature (°C)
HIV+
HIV–
250
200
37.54
36.67
0.60
0.45
<
0.001
SD
=
standard deviation, BMI
=
body mass index, SBP
=
systolic blood pres-
sure, DBP
=
diastolic blood pressure.
Table 2. Laboratory characteristics of the study population (
n
=
250)
Parameters
HIV-positive patients
(mean + SD)
Non-HIV-negative
controls (mean + SD)
Na
+
(mmol/l)
131.5
±
4.1
134.2
±
4.2
K
+
(mmol/l)
3.2
±
0.2
4.2
±
0.3
HCO
3
+
(mmol/l)
22.2
±
0.5
23.3
±
1.1
Urea (mmol/l)
5.8
±
0.3
6.1
±
0.6
Ca
2+
(mmol/l)
2.1
±
0.1
2.4
±
0.2
Albumin (g/l)
22.1
±
0.8
3.5
±
0.8
CD4 cells/ml (median)
390
645
SD
=
standard deviation, Na
+
=
serum sodium, K
+
=
serum potassium, HCO
3
+
=
serum bicarbonate, Ca
2+
=
serum calcium.
Table 3. Various ECG abnormalities in the study population
ECG abnormalities
Treatment-naïve
HIV+ patients,
n (
%)
HIV-negative
subjects,
n (
%)
p-
value
Sinus tachycardia
160 (64)
24 (12)
<
0.001
Sinus bradycardia
2 (0.8)
14 (7)
0.201
Prolonged QTC
120 (48)
16 (8)
<
0.001
Shortened PR interval (WPW)
2 (0.8)
0
<
0.001
ST depression
75 (30)
4 (2)
<
0.001
T-wave inversion
54 (21.6)
16 (8)
0.011
Left-axis deviation
4 (1.6)
4 (2)
<
0.001
Left atrial enlargement
32 (12.8)
16 (8)
0.048
1st degree heart block
6 (2.4)
0
0.005
Left anterior hemiblock
2 (0.8)
0
0.024
Incomplete RBBB
4 (1.6)
0
0.012
RVH
2 (0.8)
4 (2)
0.684
LVH
35 (14)
20 (10)
0.044
Ventricular ectopics
10 (4)
2 (1)
0.019
Atrial ectopics
2 (0.8)
0
0.041
Low QRS in all leads
10 (4)
0
0.068
Low QRS in limb leads
8 (3.2)
0
0.074
RBBB
=
right bundle branch block, RVH
=
right ventricular hypertrophy, LVH
=
left ventricular hypertrophy.