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CARDIOVASCULAR JOURNAL OF AFRICA • Volume 27, No 6, November/December 2016
AFRICA
357
A semi-urban community is one with a population of between
500 and 5 000, with basic amenities such as secondary and
primary schools, electricity and a few primary healthcare (PHC)
centres, with few private clinics.
12
In a semi-urban community,
most inhabitants are individuals with low socio-economic status,
mainly artisans, traders and low-income workers who live in
over-crowded areas with poor sanitary conditions. There is
an adaption to a Western lifestyle in semi-urban communities
compared to a rural community.
This was a cross-sectional, community-based study in
which 750 participants were recruited. At the community
level, screening of residents who volunteered to participate was
undertaken by trained interviewers until approximately equal
numbers of participants were selected from each of the selected
sites. A person not normally resident in the community was not
included in the analysis (even if screened).
Community approval and entry was facilitated after interacting
with the heads of these communities, religious leaders and other
community leaders and also by meeting with the health workers
of PHCs available in these communities. The purpose of such
meetings was to explain the aims of the study and obtain
communal consent. The study was approved by the institutional
ethics committee of the Federal Medical Centre, Ido-Ekiti.
A questionnaire, which was researcher-developed and
interviewer-administered, was used to obtain data from the
participants. The questionnaire contained two parts, the
first being demographic information including age, gender,
occupation, monthly income and family history of hypertension.
The second part involved measurement of height, weight, waist
and hip circumferences, and blood pressure.
Height was measured without shoes or headgear, using a
wooden platform stadiometer ruled to the nearest 0.5 cm, while
weight was measured to the nearest 0.5 kg using a weighing scale
(Hanson HX5000 electronic bathroom scale). Body mass index
(BMI) was calculated as weight (kg) divided by the square of the
height in metres (m
2
). Waist circumference (WC) was measured to
the nearest 0.1 cm, at the midpoint between the costal margin and
iliac crest, at the end of normal expiration, using a non-stretchable
measuring tape. Hip circumference (HC) was measured at the
level of the greater trochanters (widest diameter of hips) to the
nearest 0.1 cm with a measuring tape, while the subject was
standing with the arms by the side and feet together.
13,14
The waist-
to-hip ratio (WHR) was calculated from WC:HC
Blood pressure was measured on the left arm in a seated position
with the subjects in a relaxed state, using a validated electronic
blood pressure monitor (Omron MX2 Basic, Omron Healthcare
Co, Ltd, UK). A standard aneroid sphygmomanometer with an
adult cuff size (Medicare instrument, NUXI, Ltd, China) was used
to confirm the reading by electronic monitor. Blood pressure was
classified according to the seventh Joint National Committee and
Treatment of High Blood Pressure (JNC7)
15
criteria into normal,
prehypertension, stage 1 hypertension and stage 2 hypertension.
Hypertension was defined as systolic blood pressure (SBP)
≥
140
mmHg and/or diastolic blood pressure (DBP)
≥
90 mmHg and/or
concomitant use of antihypertensive medications.
16
Statistical analysis
The Statistical Package for Social Sciences software version 17
(SPSS Inc, Chicago, IL) was used for data analysis. Continuous
variables are expressed as means
±
standard deviation (SD)
while categorical variables are presented as frequencies and
percentages. Comparison for statistical significance was done
with the Student’s
t
-test for continuous variables that were
normally distributed, or Chi-square analysis for categorical
variables. All tests were two-tailed with
p
<
0.05 taken as
statistical significance.
Results
A total of 856 participants were encountered for the study but
only 750 participants had complete data for analysis, which
represented a response rate of 87.6%. The majority were females
(529, 70.5%). The mean age of the participants was 61.7
±
18.2
years. Farmers and petty traders dominated the occupation
of the participants (520, 68.4%). With regard to educational
level, the majority (77.6%) had either no formal education or
Table 1. Sociodemographic and clinical characteristics
of the study population
Variable
All
(
n
=
750)
Male
(
n
=
218)
Female
(n
=
542)
p-
value
Age (years)
<
20
5 (0.7)
3 (60.0)
2 (40.0)
0.072
20–40
112 (14.9)
41 (36.9)
70 (63.1)
41–60
212 (28.3)
53 (25.6)
154 (74.4)
>
60
421 (56.1)
120 (29.1)
293 (70.9)
Mean age
±
SD
61.7
±
18.2 60.0
±
20.0 62.4
±
17.3
0.090
Marital status
Single
45 (6.0)
31 (68.9)
14 (31.1)
<
0.001
Married
434 (57.9)
177 (40.8)
257 (59.2)
Widow/widower
268 (35.7)
11 (4.1)
257 (95.9)
Divorced
3 (0.4)
2 (66.7)
1 (33.3)
Occupation
Unemployed
85 (11.3)
14 (16.5)
71 (83.5)
<
0.001
Petty trader
309 (41.2)
9 (2.9)
300 (97.1)
Farmer
211 (28.1)
111 (52.6)
100 (47.4)
Unskilled labourer
52 (6.9)
35 (67.3)
17 (32.7)
Clerk/typist
1 (0.1)
1 (100.0)
0 (0.0)
Professional
40 (5.3)
16 (40.0)
24 (60.0)
Other
52 (6.9)
35 (67.3)
17 (32.7)
Educational level
None
413 (55.1)
89 (21.5)
324 (78.5)
<
0.001
Primary
169 (22.5)
54 (32.0)
115 (68.0)
Secondary
107 (14.3)
52 (48.6)
55 (51.4)
Tertiary
61 (8.1)
26 (42.6)
35 (57.4)
Income (Naira)
<
20 000
626 (83.5)
159 (25.4)
467 (74.6)
<
0.001
20 000–40 000
89 (11.9)
40 (44.9)
49 (55.1)
41 000–60 000
26 (3.5)
16 (61.5)
10 (38.5)
61 000–00 000
6 (0.8)
5 (83.3)
1 (16.7)
>
100 000
3 (0.4)
1 (33.3)
2 (66.7)
BMI (kg/m
2
)
<
25
525 (70.0)
172 (77.8)
353 (66.7)
<
0.001
25–29.9
161 (21.5)
44 (19.9)
117 (22.1)
≥
30
64 (8.5)
5 (2.3)
59 (11.2)
Mean BMI (kg/m
2
)
23.4 (5.5)
22.6 (5.5)
23.7 (5.5)
0.015
Mean WC (cm)
85.7 (11.9)
83.3 (9.6)
86.7 (12.7)
<
0.001
Mean WHR
0.93 (0.36)
0.93 (0.06)
0.93 (0.43)
0.919
Mean SBP (mmHg)
142.4 (28.6) 142.3 (28.7) 142.4 (28.5)
0.976
Mean DBP (mmHg)
81.6 (14.2)
81.1 (15.0)
81.8 (13.8)
0.534
Fisher’s exact, values are mean (SD) or
n
(%).