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RESEARCH ARTICLE
SA JOURNAL OF DIABETES & VASCULAR DISEASE
20
VOLUME 17 NUMBER 1 • JULY 2020
These studies also found that all measures of body composition
(WC, BMI and WHtR) significantly correlated with WC and WHtR.
BMI and WC positively correlated with SBP in the normal group.
The same trend was observed in other studies, where a statistically
significant association was found between hypertension and BMI
among employees working at Port Said University.
55
The results of
the study also found that, in the overweight group, WC correlated
significantly with SBP, and WHtR correlated positively with both SBP
and DBP. These findings correspond with those of Dua
et al
.,
51
who
showed a statistically significant positive correlation between all the
anthropometric measures and BP parameters (SBP and DBP). These
findings are also in agreement with other studies, which found
that anthropometric variables such as BMI, WC and WHtR were
frequently positively associated with BP among employees in West
Africa.
28
Obesity emerged as a strong predictor of hypertension
among employees in Ghana.
31
The high prevalence of overweight/obesity in this study linked to
the prevalence of hypertension agrees with the International Study
of Salt and Blood Pressure,
56
which reported a strong, significant,
independent association between BMI and BP. From the literature,
it was revealed that obesity is associated with more pronounced
changes in BP during a 24-hour cycle and a higher SBP, DBP and
pulse pressure, indicating autonomic dysfunction or hypertension.
57
All these risk factors may contribute to the increase in prevalence of
chronic diseases and absenteeism among employees.
58,59
The major constraint of the study was the difficulty in collecting
data from all the municipalities that participated. Inclusion of all
employees from the Vhembe district would have enriched the data
collected. In addition, it was not feasible to collect 24-hour BP data
from the participants due to logistical challenges. This would have
shed more light on the observed relationships between WC and
WHtR measures. It would be important in future studies to address
these challenges.
Conclusion
Females showed a higher percentage of obesity and hypertension
than their male counterparts. The obese group showed a high
prevalence of hypertension compared with the other groups. Body
composition measures were associated with BP parameters (more
especially, BMI, WC and WHtR), which showed a positive significant
relationship in both normal and overweight groups. Therefore,
this study recommends that intervention regimes designed to
address the risk of obesity and hypertension should focus on the
awareness of cardiovascular diseases, impaired quality of life, and
low productivity associated with obesity and hypertension among
local government employees in the Vhembe district of Limpopo
Province.
The willingness of the Vhembe local municipality employees to
participate in the study is highly appreciated. The University of
Venda biokineticist interns: Walter, Precious, Gudani and Merlyn
and third-year biokinetics students Tsakani, Fulufhelo, Pearl,
Rixongile, Ruth and Emmanuel are acknowledged for their roles
in data collection and capturing. Furthermore, Ms Frazer Maake is
thanked for her support in organising satellites within the Vhembe
district where the study took place. The financial support by the
University of Venda towards the study is acknowledged.
References
1. Ng M, Fleming T, Robinson M, Thomson B, Graetz N. Global, regional, and
national prevalence of overweight and obesity in children and adults during
1980–2013: a systematic analysis for the Global Burden of Disease Study.
Lancet
2014;
384
: 766–781.
2. Salvetti G, Santini F, Versari D, Virdis A, Fierabracci P. Fat distribution and
cardiovascular risk in obese women.
J Obes Metab
2008;
4
: 202–207.
Table 4.
Descriptive statistics of age, height, BMI, WC, SBP, DBP and
WHtR for the overweight and obese group by gender
Variables
n
Min
Max Mean
SD
F
p
-value
Age, years
Men
108
25.0
65.0
51.84 8.60
1.096 0.30
Women
201
24.0
65.0
52.95 9.07
Height, cm
Men
108 107.0 189.0 168.34 11.90 68.607 < 0.001
Women
201 135.0 182.0 159.46 6.94
Weight, kg
Men
108
55
132
83.97 13.43 0.009 0.93
Women
201
51
172
83.80 15.67
BMI, kg/m
2
Men
108 25.10 55.11 29.76 4.81 24.941 < 0.001
Women
201 25.09 64.06 32.91 5.52
WC, cm
Men
108
70
170
98.06 11.96 0.645 0.42
Women
201
37
152
99.41 15.04
SBP, mmHg
Men
108
91.0 193.0 140.44 20.21 1.308 0.25
Women
201
86.0 229.0 143.61 24.61
DBP, mmHg
Men
108
54.0 115.0 80.23 11.12 3.041 0.08
Women
201
54.0 141.0 82.79 12.93
WHtR
Men
108
0.42
0.91 0.5786 0.06 18.969 < 0.001
Women
201
0.23
0.94 0.6215 0.09
BMI = body mass index, WC = waist circumference. SBP = systolic blood
pressure, DBP = diastolic blood pressure, WHtR= waist-to-height ratio,
n
= number, SD = standard deviation.
Table 5.
Correlation coefficients (
r
) for normal, overweight and obese
groups
Groups
BW,
r
BMI,
r
WC,
r
SBP,
r
DBP,
r
WHtR,
r
Normal
BW (kg)
–
0.51** 0.50**
0.05
–0.02
0.09
BMI
0.51**
–
0.42**
0.15*
0.004 0.52**
WC
0.50**
0.42**
–
0.26**
0.11
0.82**
WHtR
0.09
0.52** 0.82** 0.29**
0.14
–
Overweight
BW (kg)
–
0.22* 0.51**
0.01
0.08
–0.09
BMI
0.22*
–
0.23*
0.17
0.23* 0.44**
WC
0.51**
0.23*
–
0.23*
0.18
0.71**
WHtR
–0.09
0.44** 0.71** 0.26**
0.19* –
Obese group
BW (kg)
–
0.57** 0.59**
0.02
0.09
0.19*
BMI
0.57**
–
0.47**
0.04
0.11
0.57**
WC
0.59**
0.47**
–
0.15
0.07 0.78**
WHtR
0.19*
0.57** 0.78** 0.14
0.08
–
**Correlation is significant at the 0.01 level (2-tailed).
*Correlation is significant at the 0.05 level (2-tailed).
BW = body weight, BMI = body mass index, WC = waist circumference,
SBP = systolic blood pressure, DBP = diastolic blood pressure, WHtR = waist-
to-height ratio.