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CARDIOVASCULAR JOURNAL OF AFRICA • Volume 30, No 6, November/December 2019
364
AFRICA
(161.76
±
9.27 cm). The mean weight was 64.90
±
7.97 kg for the
total group, in which men were heavier (66.75
±
7.93 kg) than
women (60.75
±
6.38 kg). Regarding BMI, the mean value for the
total group was 22.99
±
2.05 kg/m²; however, specific values were
22.89
±
2.13 kg/m² for men and 23.23
±
1.83 kg/m² for women.
Mean BP data for the total group were as follows: SBP
(138.53
±
23.10 mmHg), DBP (77.04
±
13.62 mmHg), whereas
corresponding values for men and women, respectively, were
SBP 142.20
±
23.05 mmHg and DBP 78.05
±
14.53 mmHg, and
SBP 130.31
±
21.17 mmHg and DBP 74.80
±
11.11 mmHg. The
mean height for participants who were overweight and obese
was 164.15
±
8.39 cm and 160.87
±
10.73 cm, respectively, for the
total participants. In total, participants who were overweight and
obese had a mean weight of 76.67
±
7.77 and 92.85
±
14.67 kg,
respectively. However, the mean BMI for overweight and obese
groups was, respectively, 28.42
±
1.46 and 35.92
±
4.92 kg/m².
For the total group, the average SBP for overweight and obese
participants, respectively, was 137.74
±
21.71 and 145.76
±
24.06
mmHg, with a mean DBP of 79.26
±
11.26 and 84.90
±
12.49
mmHg.
Table 3 presents ANOVA results for the variables of interest
according to the three BMI categories. The results show
significant group differences (
p
=
0.05) for height, with normal
and overweight men being taller than underweight and obese
counterparts, while no significant group differences (
p
=
0.18)
were found among the women’s BMI categories. Significant
group differences (
p
≤
0.05) were observed for body weight, BMI,
WC and WHtR, with the overweight and obese groups having
high mean values. Additionally, the results showed significant
differences in the SBP and DBP for both overweight and obese
women. No significant group differences (
p
≥
0.05) were found in
the blood pressure variables for men.
Provided in Table 4 are the descriptive data (mean, minimum,
maximum and SD) for the overweight and obese groups by
gender. The mean age and height of the participants in the
obese group were as follows: men (51.84
±
8.60 years; 168.34
±
11.90 cm) and women (52.95
±
9.07 years; 159.46
±
6.94 cm).
Corresponding data for body weight included the following:
men (83.97
±
13.43 kg) and women (83.80
±
15.67 kg). The mean
BMI of the obese group was 29.76
±
4.81 kg/m² in men, and
32.91
±
5.52 kg/m² in women, with a mean WC of 98.06
±
11.96
and 99.41
±
15.04 cm obtained for men and women, respectively.
In the obese group the mean SBP was 140.44
±
20.21 mmHg
for men, and 143.61
±
24.61 mmHg for women. However, the
mean DBP was 80.23
±
12.93 and 82.79
±
12.93 mmHg for the
men and women, respectively. The results also show that there
was a significant difference (
p
≤
0.05) in height, BMI and WHtR
among men and women.
Table 5 presents the correlation coefficients for the normal,
overweight and obese groups. In all three BMI groups, BW,
WC, BMI and WHtR were significantly and positively related to
each other. In the normal group, SBP was positively (
p
≤
0.05)
correlated with BMI (
r
=
0.150), WC (
r
=
0.26) and WHtR (
r
=
0.29). In the overweight category, WC was significantly (
p
≤
0.05)
and positively correlated with SBP (
r
=
0.23), and WHtR was
positively associated with both SBP (
r
=
0.26) and DBP (
r
=
0.19).
Discussion
The purpose of this study was to investigate the relationship
between obesity and BP among employees in the Vhembe
district municipality of the Limpopo Province, South Africa.
The study showed that 27 and 35% of the total participants were
overweight and obese, respectively. These findings were higher in
comparison to a study by Lategan,
et al.
,
41
which found that half
of the participants from the black urban population of the Free
State community had a BMI above normal (23% overweight and
32% obese). The results of this study concur with the findings
of WHO,
42
which estimated that 45.1% of the South African
population were overweight and obese. Schutte,
et al
.
34
reported a
prevalence of 48% overweight and obesity among South African
employees from 18 companies participating in health-screening
programmes.
The findings of this study, according to gender, showed that
females were more overweight and obese (29, 48%) compared to
males (24, 17%). This is higher when compared to findings by
the South African Demographic and Health Survey,
43
reporting
that 18.7% of urban black men were overweight and 8.1% were
obese, with 27.1% of urban black women being overweight and
33.8% obese. Our findings confirmed the trend that black South
African women have substantially higher BMIs than their male
counterparts. Overweight or obese individuals are at greater risk
of developing metabolic (type 2 diabetes and dyslipidaemia) and
non-metabolic disorders.
44
The study also found a 25% prevalence of hypertension in the
total group; this is lower when compared with a study by Maepa
et al
,
45
which reported a 39.5% prevalence of hypertension
among employees in the gold mines of Gauteng’s Harmony
Gold Mining Company in South Africa. This also corresponds
with findings by Owalabi
et al
.,
46
which revealed that 49.2% of
the Buffalo City metropolitan municipality adults had a high
prevalence of hypertension. The findings of the study are also
Table 2. Descriptive statistics (mean and standard deviations) of the men, women and total participants in the overweight and obese groups
Non-obese group, mean
±
SD
p
-values
Overweight and obese group,
mean
±
SD (
n
=
274)
p
-values
p
-values
Total participants
Men (
n
=
123)Women (
n
=
55)
Total participants
Overweight
Obese group
(
n
=
178)
OV (
n
=
121) OB (
n
=
153) Men (
n
=
49) Women (
n
=
72)
Men (
n
=
35) Women (
n
=
118)
Height 167.94
±
8.80 170.71
±
7.19 161.76
±
9.27
<
0.001 164.15
±
8.39 160.87
±
10.73 170.22
±
7.38 160.01
±
6.26
<
0.001 165.60
±
17.34 159.47
±
7.31 0.003
Weight 64.90
±
7.97 66.75
±
7.93 60.75
±
6.38
<
0.001 76.67
±
7.77 92.85
±
14.67 81.50
±
7.68 73.38
±
5.93
<
0.001 95.09
±
14.77 92.19
±
14.77 0.31
BMI
22.99
±
2.05 22.89
±
2.13 23.23
±
1.83 0.30 28.42
±
1.46 35.92
±
4.92 28.09
±
1.42 28.65
±
1.46 0.04 34.97
±
5.06 36.20
±
4.87 0.19
WC 84.20
±
11.02 85.24
±
12.30 81.85
±
6.92 0.05 93.92
±
10.76 105.42
±
14.42 96.53
±
7.13 92.15
±
12.39 0.03 105.81
±
15.70 105.31
±
14.08 0.86
SBP 138.53
±
23.10 142.20
±
23.05 130.31
±
21.17 0.001 137.74
±
21.71 145.76
±
24.06 138.45
±
18.07 137.25
±
23.98 0.77 138.23
±
21.06 147.99
±
24.52 0.05
DBP 77.04
±
13.62 78.05
±
14.53 74.80
±
11.11 0.14 79.26
±
11.26 84.90
±
12.49 80.67
±
10.97 78.31
±
11.43 0.26 79.57
±
10.49 86.48
±
12.63 0.004
WHtR 0.50
±
0.07 0.50
±
0.07 0.51
±
0.05 0.58 0.57
±
0.07 0.65
±
0.08 0.57
±
0.04 0.58
±
0.08 0.43 0.62
±
0.07
0.66
±
0.08 0.04
OW
=
overweight; OB
=
obese.