CARDIOVASCULAR JOURNAL OF AFRICA • Volume 25, No 1, January/February 2014
AFRICA
29
agreement between the ATP III and JIS criteria for identifying
individuals with the metabolic syndrome. A
p-
value
<
0.05 was
considered statistically significant.
Results
A complete data set was collected for 615 subjects (52.2%
women). Compared with women (Table 1), men had higher
mean values for height, WHR, creatinine and uric acid levels
(all
p
<
0.001), and PP (
p
=
0.007). Women had higher mean
values for HDL-C, WC, HC, BMI (all
p
<
0.001), and heart
rate (
p
=
0.003). Age, weight, SBP, DBP, MBP, and glucose,
total cholesterol, LDL-C, VLDL-C, and triglyceride levels were
similar in both sexes.
Table 2 shows distribution of risk factors, socio-economic
and educational characteristics of the study population. Current
smoking was higher in men (
p
=
0.035), whereas prevalence
of overweight, obesity and low HDL-C levels were higher in
women (all
p
<
0.001). However, prevalence of hypertension,
diabetes, hypercholesterolaemia, hypertriglyceridaemia and high
LDL-C levels were similar in both sexes (Table 2).
The overall crude prevalence of the metabolic syndrome was
17.6% [age-standardised: 8.7%, 95% confidence interval (CI):
6.8–11.3] for the ATP III criteria and 27.8% (age-standardised:
14.1.0%, 95% CI: 11.6–17.1) for the JIS criteria. As expected, the
crude prevalence was higher in women than in men, irrespective
of the criteria used (Table 3). In both sexes, the prevalence of
the metabolic syndrome increased with age, however, women
showed a higher prevalence in all age groups from 30 years and
older (Table 3). Regarding socio-economic class and educational
level (Table 4), there was no significant relationship of these
factors with the metabolic syndrome in both sexes.
Table 1. Characteristics of the participants according to gender
Characteristics
All
Men
Women
p
-value
Number (%)
615 (100)
294 (47.8)
321 (52.2) 0.392
Age (years)
44.5
±
10.6
45.1
±
11.1 44.0
±
10.1 0.176
Weight (kg)
68.6
±
15.3 68.0
±
14.9 69.2
±
15.7 0.349
Height (cm)
163.3
±
7.9 167.4
±
7.1 159.6
±
6.6
<
0.001
WC (cm)
82.1
±
13.3 80.1
±
12.9 83.9
±
13.5
<
0.001
HC (cm)
95.7
±
11.3 91.5
±
9.4 99.5
±
11.4
<
0.001
WHR
0.86
±
0.09 0.87
±
0.08 0.84
±
0.09
<
0.001
BMI (kg/m
2
)
25.7
±
5.4
24.1
±
4.3 27.1
±
5.8
<
0.001
SBP (mmHg)
134.7
±
24.9 136.5
±
22.7 133.0
±
26.6 0.087
DBP (mmHg)
82.6
±
14
82.7
±
14.2 82.5
±
13.8 0.862
PP (mmHg)
52.1
±
14.9 53.8
±
13.2 50.5
±
16.2 0.007
MBP (mmHg)
100.0
±
16.9 100.6
±
16.4 99.4
±
17.5 0.351
Heart rate (bpm)
68
±
10
67
±
10
69
±
10
0.003
Glucose (mg/dl)
(mmol/l)
94.0
±
21
(5.22
± 1.17)
94.9
±
20
(5.27
± 1.11)
93.2
±
21.8
(5.17
± 1.21)
0.313
Creatinine (mg/dl)
(
μ
mol/l)
1.1
±
0.2
(97.24
± 17.68)
1.2
±
0.2
(106.08
± 17.68)
1.0
±
0.2
(88.40
± 17.68) <
0.001
Uric acid (mg/dl)
5.4
±
1.7
6.1
±
1.7
4.8
±
1.4
<
0.001
TC (mg/dl)
(mmol/l)
191.5
±
38.9
(4.96
± 1.01)
189.5
±
41.4
(4.91
± 1.07)
193.2
±
36.5
(5.0
± 0.95)
0.239
HDL-C (mg/dl)
(mmol/l)
46.0
±
10.9
(1.19
± 0.28)
44.1
±
10.3
(1.14
± .027)
47.6
±
11.2
(1.23
± 0.29) <
0.001
LDL-C (mg/dl)
(mmol/l)
125.5
±
40.1
(3.25
± 1.04)
125.0
±
41.8
(3.24
± 1.08)
125.9
±
38.7
(3.26
± 1.0)
0.796
VLDL-C (mg/dl)
(mmol/l)
20.0
±
8.0
(0.52
± 0.21)
20.4
±
8.3
(0.53
± 0.21)
19.7
±
7.7
(0.51
± 0.20)
0.339
TGL (mg/dl)
(mmol/l)
100.2
±
40.0
(1.13
± 0.45)
101.8
±
41.7
(1.15
± 0.47)
98.7
±
38.4
(1.12
± 0.43)
0.339
Values are means
±
standard deviation. WC, waist circumference; HC,
hip circumference; WHR, waist-to-hip ratio; BMI, body mass index; SBP,
systolic blood pressure; DBP, diastolic blood pressure; PP, pulse pressure;
MBP, mean blood pressure; TC, total cholesterol; HDL-C, high-density
lipoprotein cholesterol; LDL-C, low-density lipoprotein cholesterol;
VLDL-C, very low-density lipoprotein cholesterol; TGL, triglycerides.
Table 2. Risk factors, educational level and socio-economic
class of the study population
Characteristics
All
Men
Women
p
-value
Hypertension,
n
(%)
278 (45.2) 136 (46.3) 142 (44.2)
0.615
Current smokers,
n
(%)
39 (6.3)
25 (8.5)
14 (4.4)
0.035
Diabetes,
n
(%)
35 (5.7)
16 (5.4)
19 (5.9)
0.799
Overweight,
n
(%)
180 (29.3)
80 (27.2) 100 (31.2)
<
0.001
Obesity,
n
(%)
120 (19.5)
27 (9.2)
93 (29.0)
<
0.001
High TC,
n
(%)
68 (11.1)
31 (10.5)
37 (11.5)
0.698
High TGL,
n
(%)
77 (12.5)
37 (12.6)
40 (12.5)
0.963
High LDL-C,
n
(%)
121 (19.7)
61 (20.7)
60 (18.7)
0.522
Low HDL-C,
n
(%)
308 (50.1) 108 (36.7) 200 (62.3)
<
0.001
Education level
0.926
Low,
n
(%)
213 (34.6) 110 (37.4) 103 (32.1)
Medium,
n
(%)
150 (24.4)
69 (23.5)
81 (25.2)
High,
n
(%)
252 (41.0) 115 (39.1) 137 (42.7)
Socio-economic class
0.392
Low,
n
(%)
154 (25.0)
81 (27.6)
73 (22.7)
Middle,
n
(%)
156 (25.4)
77 (26.2)
79 (24.6)
Upper middle,
n
(%)
152 (24.7) 66 (22.4)
86 (26.8)
Upper,
n
(%)
153 (24.9) 70 (23.8)
83 (25.9)
Values are number of subjects (
n
) and percentages (%).
Table 3. Crude and age-standardised prevalence of the
metabolic syndrome in men and women according to
atp iii and jis criteria
Age group (years)
n
ATP III
JIS
Men (
n
=
294)
<
30
40
2 (5.0)
3 (7.5)
30–39
52
2 (3.8)
4 (7.7)
40–49
89
8 (9.0)
15 (16.9)
50–59
90
10 (11.1)
23 (25.6)
≥
60
23
3 (13.0)
5 (21.7)
Total crude
294
25 (8.5)
50 (17.0)
Age-standardised
–
4.8
9.0
Women (
n
=
321)
<
30
32
0 (0.0)
1 (3.1)
30–39
71
8 (11.3)
13 (18.3)
40–49
125
43 (34.4)
62 (49.6)
50–59
79
27 (34.2)
37 (46.8)
≥
60
14
5 (35.7)
8 (57.1)
Total crude
321
83 (25.9)
121 (37.7)
Age-standardised (%)
–
12.6
19.2
Overall (
n
=
615)
Crude
615
108 (17.6)
171 (27.8)
Age-standardised (%)
–
8.7
14.1
Values are
n
(%). ATP III, National Cholesterol Education Program Third
Adult Treatment Panel; JIS, Joint Interim Statement.
