CARDIOVASCULAR JOURNAL OF AFRICA • Vol 22, No 5, September/October 2011
252
AFRICA
three different ferritin concentrations (low, normal and high)
is presented in Table 4. In men, mean (geometric) WC (
p
<
0.0001) and WHR (
p
<
0.0001) were significantly higher in the
high-ferritin group than the low-ferritin group before adjusting
for age, BMI and smoking but WC only remained significant (
p
=
0.014) after adjusting for age, BMI and smoking. Moreover,
mean (geometric) WC (
p
<
0.0001) and WHR (
p
<
0.0001)
of the men were significantly higher in the high-ferritin group
than the normal-ferritin group before adjusting for age, BMI
and smoking. This was not retained after adjusting for age, BMI
and smoking. A significantly higher mean (geometric) BMI (
p
=
0.001) was found in the high-ferritin group compared to the
normal-ferritin group before adjusting for age and smoking. The
high-ferritin group had a significantly higher mean (geometric)
body fat compared to the low-ferritin group (
p
=
0.015) and the
normal-ferritin group (
p
<
0.0001) before adjusting for age, BMI
and smoking.
For women, mean (geometric) WC and WHR were signifi-
cantly higher in the high-ferritin group than the low-ferritin
group before (
p
<
0.0001,
p
<
0.0001, respectively) and after
(
p
=
0.002,
p
=
0.018, respectively) adjusting for age, BMI and
smoking. WC and WHR were also higher in the high-ferritin
group than the normal-ferritin group before (
p
=
0.033,
p
=
0.005, respectively) and after (
p
<
0.0001,
p
=
0.014, respec-
tively) adjusting for age, BMI and smoking. Women in the
normal-ferritin group had higher mean (geometric) BMI (
p
=
0.032) than those in the low-ferritin group before adjusting for
age and smoking.
TABLE 3. COMPARISON OF IRON INDICESACCORDINGTOWHR CATEGORIES
Variable
Normal WHR
High WHR
G-Mean (SE)
Min, max
G-Mean (SE)
Min, max
Men
(WHR
>
0.95,
n
=
681, 95.78%)
(WHR
>
0.95,
n
=
30, 4.22%)
Serum Fe (
µ
mol/l)
16.43 (0.32)
0.74, 63.94
18.40
#
(2.48)
4.73, 73.42
Serum TIBC (
µ
mol/l)
63.94 (0.50)
28.77, 197.22
62.17 (2.53)
42.57, 102.42
Transferrin saturation (%)
25.71 (0.53)
1.34, 102.22
29.61 (3.26)
7.41, 79.95
Serum ferritin (
µ
g/l)
100.80 (11.48)
1.00, 2877.17
217.28* (111.57)
30.00, 2427.20
Hb (g/dl)
13.29 (0.08)
4.70, 22.90
13.60 (0.51)
9.80, 21.10
Women
(WHR
>
0.80,
n
=
697, 73.21%)
(WHR
>
0.80,
n
=
255, 26.79%)
Serum Fe (
µ
mol/l)
13.26 (0.29)
1.18, 56.30
12.78 (0.45)
0.26, 59.85
Serum TIBC (
µ
mol/l)
69.34 (0.52)
29.13, 171.12
65.21*
#
(0.80)
36.93, 157.26
Transferrin saturation (%)
19.05 (0.45)
0.74, 85.46
19.54 (0.77)
0.35, 97.03
Serum ferritin (
µ
g/l)
32.29 (5.44)
0.28, 2678.53
67.86*
#
(11.44)
0.50, 1951.17
Hb (g/dl)
11.90 (0.07)
4.70, 20.50
12.27*
#
(0.16)
5.70, 31.10
*Significant difference between normal and high WHR before adjusting for age, BMI and smoking (
p
<
0.05).
#
Significant difference between normal and high WHR after adjusting for age, BMI and smoking (
p
<
0.05). G-Mean: geometric mean, Hb:
haemoglobin, SE: standard error, TIBC: total iron-binding capacity, WHR: waist-to-hip ratio.
TABLE 4. COMPARISON OFANTHROPOMETRIC INDICESACCORDINGTO SERUM FERRITIN CONCENTRATION
Low-ferritin group (ferritin
<
12
µ
g/l) Normal-ferritin group (ferritin 12–150
µ
g/l) High-ferritin group (ferritin
<
150
µ
g/l)
Variable
G-Mean (SE)
Min, max
G-Mean (SE)
Min, max
G-Mean (SE)
Min, max
Men
(
n
=
23, 3.23%)
(
n
=
418, 58.79%)
(
n
=
270, 37.97%)
BMI (kg/m
2
)
20.64 (0.73)
16.42, 31.50
20.29 (0.15)
14.71, 36.91
21.64
®
(0.31)
13.76, 65.39
WC (cm)
69.08 (1.30)
60.20, 83.40
72.00
#
(0.40)
53.60, 114.50
77.52
+®$
(0.61)
57.00, 126.20
WHR
0.80 (0.01)
0.71, 0.92
0.82* (0.00)
0.59, 1.05
0.86
+®
(0.00)
0.71, 1.52
Body fat (%)
19.29 (1.48)
12.53, 36.71
19.97 (0.29)
9.22, 37.15
22.29
+®
(0.52)
9.17, 39.30
TSF (mm)
7.75 (0.85)
4.90, 18.20
7.09 (0.24)
2.00, 37.30
7.77 (0.32)
1.80, 37.10
SSF (mm)
8.69 (1.01)
5.50, 19.90
9.27 (0.27)
3.40, 40.00
10.32 (0.40)
3.00, 38.10
Women
(
n
=
155, 16.28%)
(
n
=
662, 69.54%)
(
n
=
135, 14.18%)
BMI (kg/m
2
)
24.50 (0.50)
15.45, 45.96
26.40* (0.26)
15.39, 53.64
26.74 (0.64)
14.60, 48.76
WC (cm)
72.47 (0.89)
46.50, 107.50
77.50* (0.50)
54.50, 130.20
81.83
+®$@
(1.15)
55.00, 119.60
WHR
0.73 (0.00)
0.57, 0.96
0.75* (0.00)
0.47, 1.00
0.80
+®$@
(0.00)
0.64, 0.99
Body fat (%)
45.01 (0.87)
28.17, 68.40
47.81 (0.57)
13.30, 83.79
47.33 (1.42)
28.79, 70.55
TSF (mm)
17.86 (0.80)
4.40, 51.70
19.10 (0.38)
4.40, 50.20
19.12 (1.06)
3.50, 52.10
SSF (mm)
17.15 (0.92)
5.40, 52.90
18.75 (0.51)
4.60, 56.60
20.30 (1.23)
4.40, 60.00
*Significant difference between negative and normal iron balance before adjusting for age, BMI and smoking at
p
<
0.05.
+
Significant difference between negative and positive iron balance before adjusting for age, BMI and smoking at
p
<
0.05.
®
Significant difference between normal and positive before adjusting for age, BMI and smoking at
p
<
0.05.
#
Significant difference between negative and normal iron balance after adjusting for age, BMI and smoking at
p
<
0.05.
$
Significant difference between negative and positive iron balance group after adjusting for age, BMI and smoking at
p
<
0.05.
@
Significant difference between normal and positive iron balance after adjusting for age, BMI and smoking at
p
<
0.05. BMI: body mass index,
G-Mean: geometric mean, SE: standard error, SSF: subscapular skinfold, TSF: triceps skinfold, WC: waist circumference, WHR: waist-to-hip ratio.
