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RESEARCH ARTICLE
SA JOURNAL OF DIABETES & VASCULAR DISEASE
18
VOLUME 17 NUMBER 1 • JULY 2020
shown in the results, the mean height for the non-obese group was
167.94 ± 8.80 cm (from the total group of 178 participants). Men
were taller on average (170.71 ± 7.19 cm) than women (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
Table 2.
Descriptive statistics (mean and standard deviations) of the men, women and total participants in the overweight and obese groups
Overweight and obese group,
Non-obese group, mean ± SD
mean ± SD (n = 274)
Total participants
Total participants
Overweight
Obese group
(
n
= 178)
Men (
n
= 123) Women (
n
= 55)
p
-values OV (
n
= 121)
OV (
n
= 153) Men (
n
= 49) Women (
n
= 72)
p
-values Men (
n
= 35) Women (
n
= 118)
p
-values
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.