CARDIOVASCULAR JOURNAL OF AFRICA • Vol 23, No 6, July 2012
310
AFRICA
A preliminary investigation was done using the WHO
questionnaire, adapted to the local situation.
9
Each subject was
first rested for 10 minutes and then questioned on the presence
of diabetes, smoking and use of alcohol, sedentary or active
lifestyle, stress and eating habits. Participants were also asked
about the use of antihypertensive medication and those who were
already on antihypertensive therapy were required to produce the
drugs used.
Blood pressure (BP), weight and height were then measured,
and the body mass index was calculated (kg/m
2
). BP was
measured in both arms with a validated electronic BP monitor
(Omron Inc), recommended for STEPS-wise surveys by the
WHO.
8
Three successive measurements were taken, one minute
apart, and the mean was calculated. Any missing subjects were
seen during a second visit.
A second measurement session was performed three weeks
later in patients with BP
≥
140/90 mmHg during the first session.
Hypertension was defined as BP > 140/90 mmHg after the
second measurement session,
10
or on antihypertensive treatment,
no matter what the blood pressure values were.
The other cardiovascular risk factors studied were obesity,
alcohol use, smoking, stress, sedentary lifestyle and biological
factors (diabetes, hypercholesterolaemia, hypertriglyceridaemia).
Obesity was defined by a body mass index
≥
30 kg/m
2
. Smoking
was defined by a consumption of at least one cigarette daily,
alcohol use by regular consumption of alcohol no matter the
quantity, sedentary by lack of physical activity or less than 30
minutes of sport activity at least three times a week. Stress was
evaluated with the rapid evaluation of Cunci
11
and was defined
as a score
≥
30.
Blood analysis was done to determine glycaemia, total
cholesterol and triglyceride levels. Some subjects refused blood
sampling, and laboratory tests were therefore conducted only
on those who accepted sampling, and no other selection criteria
were used. In total, blood analyses were done for 1 012 (520 men
and 492 women) of the 2 000 individuals involved in the study.
The blood samples were analysed at the University Hospital
of Lome, and a maximum of two hours between sampling and
arrival of the samples at the laboratory was allowed.
Diabetes was defined as fasting glycaemia > 7 mmol/l
(1.26 g/l) after two measures two weeks apart or > 11 mmol/l
(2 g/l) during the first measure. Total hypercholesterolaemia
was defined as cholesterolaemia > 5.16 mmol/l (2 g/l), and
hypertriglyceridaemia as > 1.71 mmol/l (1.5 g/l).
Statistical analysis
Confidence intervals (95% CI) and the chi-square (
χ
2
) test were
used to compare the prevalence of hypertension and other risk
factors, with a significance set at
p
< 0.05. Epi Info 6.04 was
used to record and analyse the data. Quantitative variables were
reported as mean ± standard deviation and qualitative variables
as percentages.
Results
The total number of subjects included in the study was 2 000
(898 men and 1 102 women), with an overall mean age of 39
± 10 years (40 ± 12 years for men, 38 ± 11 years for women),
ranging from 18 to 98 years (Table 1). Forty-eight per cent of
subjects had no school education, 28.5% had a primary level of
education, 18.2% had secondary-level education, and 5.3% were
university educated. According to diet, all respondents admitted
to consuming fatty and processed foods, but not much vegetables
and fruits.
We identified 532 hypertensive individuals (243 men and 289
women). The prevalence of hypertension was 26.6% (25.7% in
men and 27.6% in women,
p
= 0.09). Of the 532 hypertensive
patients, 174 subjects (32.7%) were on antihypertensive
treatment. Sixty-one per cent of hypertensive patients were
classified as stage I, and 39% were classified as stage II,
according to the JNCVII classification.
10
The prevalence of hypertension increased with age (
p
< 0.001)
(Table 2). The overall mean age of hypertensive individuals was
45 ± 10.4 years, with 45 ± 10.4 years for men and 46 ± 11.4 years
for women. The mean systolic (SBP) and diastolic (DBP) blood
pressure was 129.6 and 84.3 mmHg, respectively (Table 3).
Pre-hypertension, as defined by the JNCVII,
10
was
detected in 641 subjects (32%). The prevalence of other
cardiovascular risk factors were stress (43%), sedentary
lifestyle (41%), hypercholesterolaemia (26%), obesity (25.2%),
hypertriglyceridaemia (21%), active smoking (9.3%), alcohol
use (11%) and diabetes (7.3%) (Table 4).
Regarding professional groups, hypertension was observed
among the unemployed (43%), civil servants (42.4%), housewives
(54.2%), private-sector workers (23.8%), pensioners (56.2%)
TABLE 1. CHARACTERISTICS OF THE
STUDY POPULATION
Age (years)
Male,
n
(
%
)
Female,
n
(
%
) Overall,
n
(
%
)
18–30
350 (38.9)
461 (42)
811 (40.5)
31–45
212 (23.6)
268 (24.3)
480 (24.1)
46–60
154 (17.1)
183 (16.6)
337 (16.8)
61–75
133 (14.8)
157 (14.2)
290 (14.5)
76–90
32 (3.5)
24 (2.2)
56 (2.8)
91–105
17 (1.9)
9 (0.8)
26 (1.3)
Overall
898 (100)
1102 (100)
2000 (100)
TABLE 2. PREVALENCE OF HYPERTENSION (%)
BY GENDERANDAGE
Age groups (years)
Gender 18–30 31–45 46–60 61–75 76–90 91–105
Female
8
10.7 23
52.5 88.6 100
Male
9
17.3 28.4 51
75
88
TABLE 3. MEANARTERIAL BLOOD PRESSURE
BYAGE GROUP
Age (years)
Number
SBP (mmHg)
DBP (mmHg)
18–30
811
121.7 ± 3.1
78.6 ± 2.4
31–45
337
127.7 ± 3.4
84.2 ± 2.5
46–60
480
136.1 ± 3.7
90.1 ± 3.4
61–75
290
147.2 ± 4.6
92.3 ± 3.8
76–90
56
150 ± 4.4
94 ± 3.4
91–105
26
152 ± 5.7
100 ± 4.8
Overall
2000
129.6 ± 3.5
84.3 ± 3.4
SBP = systolic blood pressure; DBP = diastolic blood pressure; mean
± standard deviation
