Cardiovascular Journal of Africa: Vol 27 No 6 (November/December 2016)

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CARDIOVASCULAR JOURNAL OF AFRICA • Volume 27, No 6, November/December 2016 356 AFRICA
Epidemiology and patterns of hypertension in semi-urban
communities, south-western Nigeria
MA Olamoyegun, R Oluyombo, SO Iwuala, SO Asaolu
Abstract
Objective: To determine the prevalence and subtypes of hyper-
tension among semi-urban residents in south-western Nigeria.
Methods: All adults aged 18 years or older in 10 semi-urban
communities were recruited for the study. The blood pressure
(BP) reading taken with a validated electronic BP monitor
after at least 10 minutes of rest was used in the analysis.
Hypertension was defined as BP ≥ 140/90 mmHg.
Results: Seven hundred and fifty subjects with a mean age of
61.7 ± 18.2 years participated in the study. The prevalence of
hypertension was 55.5%. Stage 2 hypertension was the most
common, present among 225 (54.1%) of the participants
with hypertension, and 191 (45.9%) had stage 1 hypertension.
Of those with hypertension, systolic–diastolic hypertension
(SDH) was present among 198/416 (47.6%), while isolated
systolic hypertension (ISH) and isolated diastolic hyperten-
sion (IDH) were present among 181/416 (43.6%) and 37/416
(8.9%), respectively. The prevalence of hypertension increased
significantly with age.
Conclusion: The prevalence of hypertension was high in these
semi-urban communities. Hence, increased awareness and
integrating hypertension care into primary healthcare and
other community health services in these areas may prove
beneficial in ameliorating its adverse effects.
Keywords: epidemiology, hypertension, pattern, semi-urban
Submitted 4/6/15, accepted 22/3/16
Published online 11/5/16
Cardiovasc J Afr 2016; 27: 356–360
DOI: 10.5830/CVJA-2016-037
Hypertension is regarded as a major public health problem1
and is also an important threat to the health of adults in
sub-Saharan Africa.2 Emerging evidence identifies hypertension
as a major cause of morbidity and mortality globally, including
sub-Saharan Africa.2-4 Hypertension is now recognised as one of
the most important causes of cardiovascular diseases, accounting
for almost 40% of the diseases on the African continent,
including Nigeria.5,6
According to a World Health Organisation report,
hypertension is the third cause of deaths, accounting for one
in eight deaths worldwide.7 The overall worldwide burden
of hypertension in the year 2000 was 26.4% of the adult
world population, 34.3% in developed and 65.8% in developing
countries.8 Also, about 62% of cardiovascular diseases (CVDs)
and 49% of ischaemic heart disease (IHD) are attributable
to suboptimal blood pressure (systolic blood pressure > 115
mmHg).9 Indeed, it has been projected that up to three quarters
of the world’s hypertensive population will be in economically
developing countries by the year 2025.10 Nigeria, due to its
population size and the projected increase in the prevalence of
hypertension, will face a huge economic health burden from
hypertension.
The prevalence of hypertension has been variously studied
in Nigeria, however, most studies were done among urban and
rural dwellers. In a review of hypertension prevalence in Nigeria
by Akinlua et al.11 using a blood pressure cut-off value of 140/90
mmHg, the crude prevalence of hypertension ranged from 6.2
to 48.9% and 10.0 to 47.3% for males and females, respectively.
Comparing urban versus rural differences in crude prevalence,
estimates showed an overall prevalence ranging from 17.5 to
51.6% in urban areas and 4.6 to 43.0% in rural areas. There
have been few studies done to determine the prevalence of
hypertension among dwellers in semi-urban areas, which have
mixtures of urban and rural areas.
Our study therefore aimed to assess the prevalence and
subtypes of hypertension among the population in semi-urban
communities in south-western Nigeria. The findings in this study
will further add to the available data on the increasing prevalence
of hypertension in Nigeria, thereby stimulating increased effort
by health policy makers to control the emerging health burden.
This study could also demonstrate the need for prevention and
control of hypertension in daily medical practice.
Methods
This study was conducted in Ekiti State, located in the south-
western zone of Nigeria. The state is divided into three senatorial
zones (Ekiti south, north and west). The study area, Ekiti north
senatorial zone, is made up of five local government areas (Ido/
Osi, Ikole, Moba, Ilejemeje and Oye). A total of 10 communities
(all semi-urban) were randomly selected within the senatorial
district (two communities per local government area).
Ladoke Akintola University of Technology (LAUTECH),
LAUTECH Teaching Hospital, Ogbomoso, Nigeria
MA Olamoyegun, MB BS, FWACP, FACE, ,
Department of Medicine, Endocrinology, Diabetes and
Metabolism Unit, Lagos University Teaching Hospital, Idi
Araba, Lagos, Nigeria
SO Iwuala, MB BS, FWACP, FACE
Department of Internal Medicine, LAUTECH Teaching
Hospital, Ogbomoso, Nigeria
SO Asaolu, BSc
Department of Medicine, Federal Teaching Hospital, Ido
Ekiti, Nigeria
R Oluyombo, MB BS, FMCP