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CARDIOVASCULAR JOURNAL OF AFRICA • Volume 27, No 6, November/December 2016
358
AFRICA
primary school as the highest educational level attained. Only
six (0.8%) persons were current smokers. The sociodemographic
characteristics of the subjects are shown in Table 1. Mean BMI,
WC, WHR, SBP and DBP of the study participants were 23.4
±
5.5 kg/m
2
, 85.7
±
11.9 cm, 0.93
±
0.36, 142.4
±
28.6 mmHg and
81.6
±
14.2 mmHg, respectively.
Out of the 750 participants, 116 (15.5%) had normal blood
pressure, 218 (29.0%) had prehypertension and 416 (55.5%) had
hypertension. Of the study participants, 195 (26.0%) had been
diagnosed with hypertension previously, 81 (10.9%) were on
antihypertensive medication, and 24 (3.2%) had a positive family
history of hypertension. Twenty (2.6%) said they were taking
herbal remedies for hypertension. The proportion of those
on antihypertensive medication who had good blood pressure
control of
≤
140/90 mmHg was 22.0%. Of the participants with
hypertension, isolated systolic hypertension (ISH) was present
among 181/416 (43.6%) while isolated diastolic hypertension
(IDH) and systolic–diastolic hypertension (SDH) were present
among 37 (8.9%) and 198 (47.6%), respectively (Fig. 1).
Stage 2 hypertension was the most common, being present
among 225 (54.1%) of the participants with hypertension. Of
those with hypertension 191 (45.9%) had stage 1 hypertension
(Fig. 2). Table 3 shows the gender and sociodemographic
relationships of the hypertension subtypes. ISH (67.4%) and
IDH (59.5%) were more prevalent among females compared to
males. Also, participants with ISH were significantly older than
those with IDH (
p
=
0.014). After adjusting for confounding
variables, factors associated with hypertension among the study
participants were age group, educational level and body mass
index (BMI) (Table 2).
Discussion
This study assessed the prevalence and pattern of hypertension
in its different subtypes in semi-urban communities in south-
western Nigeria. The majority of the participants were females,
as is common in most cross-sectional studies.
Married petty traders made up the majority of the population,
which was not unusual, as most people living in semi-urban areas
participate in business and petty trading. Slightly more than half
Table 2. Predictors of hypertension among the study participants
Variable
No hyper-
tension
(
n
=
334)
Hyperten-
sion
(
n
=
416)
p
-value
Gender
Male
96 (28.7)
125 (30.0)
0.697
Female
238 (71.3) 291 (70.0)
Age (years)
<
20
4 (1.2)
1 (0.2)
<
0.001
20–40
82 (24.6)
30 (7.2)
41–60
98 (29.3)
114 (27.4)
>
60
150 (44.9) 271 (65.1)
Marital status
Single
25 (7.5)
20 (4.8)
0.084
Married/widow/widower/divorced
309 (92.5) 396 (95.2)
Educational level
None
152 (45.5) 261 (62.7)
<
0.001
Primary
84 (25.1)
85 (20.4)
Secondary
62 (18.6)
45 (10.8)
Tertiary
36 (10.8)
25 (6.0)
Average family income (Naira)
<
20 000
272 (81.4) 354 (85.1)
0.472
20 000–40 000
43 (12.9)
46 (11.1)
41 000–60 000
15 (4.5)
11 (2.6)
61 000–100 000
2 (0.6)
4 (1.0)
>
100 000
2 (0.6)
1 (0.2)
BMI (kg/m
2
)
<
25
172 (77.8) 353 (66.7)
<
0.001
25–29.9
44 (19.9)
117 (22.1)
≥
30
5 (2.3)
59 (11.2)
Normal
(15.1%)
Prehypertension
(29.1%)
Stage 1
(25.5%)
Stage 2
(30.0%)
Fig. 1.
Prevalence of hypertension according to JNC7.
Isolated systolic
hypertension
(43.6%)
Systolic–diastolic
hypertension
(47.6%)
Isolated
diastolic
hyper-
tension
(8.9%)
Fig. 2.
Prevalence of hypertension according to subtypes.