CARDIOVASCULAR JOURNAL OF AFRICA • Vol 23, No 5, June 2012
AFRICA
255
Early diastolic functional abnormalities in normotensive
offspring of Nigerian hypertensives
AM ADEOYE, AA ADEBIYI, OO OLADAPO, OS OGAH, A AJE, DB OJJI, AK ADEBAYO, KC OCHULOR,
EO ENAKPENE, AO FALASE
Abstract
Background:
Some studies have suggested that diastolic
dysfunction precedes the clinical manifestation of hyperten-
sion. Whether changes in cardiac structure and function
predate the clinical manifestation of hypertension later in life
is now being investigated. The aim of this study was to assess
the differences in cardiac structure and function between the
offspring of hypertensive and normotensive parents.
Methods:
Eighty normotensive offspring of hypertensive
parents (OHyp) (41 females and 39 males) and 62 normoten-
sive offspring of normotensive parents (ONorm) (31 males
and 31 females) were recruited for echocardiography.
Results:
The mean age was 25.0 (5.31) and 24.3 (3.60) years in
the OHyp and ONorm participants, respectively (
p
=
0.369).
Other baseline parameters were comparable between the
two groups. Septal wall thickness in systole was higher in the
OHyp than the ONorm subjects [1.3 (0.35) vs 1.1 (0.25),
p
=
0.0173]. Indexed left ventricular mass [28.1 (7.33) vs 27.5
(7.23),
p
=
0.631] and relative wall thickness [(0.3 (0.10) vs
0.3 (0.90),
p
=
0.280] were similar in the two groups. The
offspring of hypertensives had lower deceleration time [149.9
(38.89) vs 169.0 (50.08) ms,
p
=
0.012], prolonged duration
of pulmonary A reverse flow [113.5 (70.69) vs 81.7 (38.31)
ms,
p
=
0.024], increased myocardial isovolumic relaxation
time [173.4 (47.98) vs 156.1 (46.74) ms,
p
=
0.033] and a
lower myocardial Em [0.2 (0.05) vs 0.3 (1.38),
p
=
0.037] and
myocardial Em/Am ratio [1.6 (0.01) vs 2.1 (0.01),
p
=
0.019]
than the offspring of normotensives.
Conclusion:
This study showed that offspring of OHyp
subjects had early diastolic functional abnormalities
when compared with offspring of ONorm participants.
Longitudinal studies are needed to determine the implica-
tions of this finding in this African population.
Department of Medicine, University College Hospital,
Ibadan, Nigeria
AM ADEOYE, MBBS, FWACP,
AA ADEBIYI, MBBS, FWACP
OO OLADAPO, MBBS, MSc, FWACP
OS OGAH, MBBS, MSc, FWACP
A AJE, MBBS, FMCP
DB OJJI, MBBS, FWACP
AK ADEBAYO, MBBS, FMCP, FWACP
KC OCHULOR, MBBS, FMCP
EO ENAKPENE, MBBS, MSc, FMCP, FWACP
AO FALASE, MBBS, MD, FMCP, FWACP, FRCP
Department of Medicine, College of Medicine, University of
Ibadan, Ibadan, Nigeria
AM ADEOYE, MBBS, FWACP
AA ADEBIYI, MBBS, FWACP
OO OLADAPO, MBBS, MSc, FWACP
AO FALASE, MBBS, MD, FMCP, FWACP, FRCP
Keywords:
diastolic function, offspring, hypertension, Nigerian
Submitted 17/8/09, accepted 6/6/11
Cardiovasc J Afr
2012;
23
: 255–259
DOI: 10.5830/CVJA-2011-030
Worldwide, hypertension is an independent risk factor for
cardiovascular morbidity and mortality.
1
Hypertension is the
most common non-communicable disease in Nigeria, a typical
example of a developing country. Despite innovations in the
drug-related management of hypertension, control remains poor.
2
Less than a third of individuals with a usual blood pressure
exceeding 140/90 mmHg are adequately treated.
3
For this reason,
global approaches now tend to focus on lifestyle changes and
studies directed at the aetiopathogenesis of hypertension. The
aim is to find markers for the early detection of hypertension so
as to initiate preventive as well as control measures as widely as
possible.
Studies on offspring of hypertensive patients have shown the
significant roles of heredity, salt intake, increased peripheral
vascular resistance, insulin resistance and increased left
ventricular (LV) mass in the pathogenesis of hypertension.
4-6
Increased LV mass and diastolic dysfunction can be either a
consequence of hypertension or precede the clinical manifestation
of hypertension.
7-10
Diastolic dysfunction has been demonstrated
in borderline hypertensive and normotensive offspring of
hypertensive patients in the absence of increased LV mass.
10-16
Since most of these studies have been carried out in Europe
and America, little is known about LV filling patterns in the
offspring of hypertensive Nigerians, in a country with increasing
prevalence of hypertension, as are most other African countries.
This study therefore aimed to determine LV diastolic filling
patterns in normotensive offspring of hypertensive Nigerians in
comparison with normotensive control subjects without a family
history of hypertension.
Methods
The study was carried out at the cardiology unit of the
Department of Medicine of the University College Hospital,
Ibadan, Nigeria. Eighty normotensive offspring aged 18 to 40
years with hypertensive parents attending the cardiac clinic of
the Hospital were recruited over a six-month period. Subjects
were offspring of consecutive hypertensive parents seen at the
medical outpatient department.
Comparable control subjects were recruited among the
children of normotensive hospital staff and relatives of patients
on treatment for conditions other than hypertension or other
chronic medical conditions. Ethical approval was obtained from
the institutional ethics review board and informed consent was
obtained from each participant.
Blood pressure was measured with a mercury
sphygmomanometer (Accosson) according to standard
