Cardiovascular Journal of Africa: Vol 27 No 1 (January/February 2016)

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CARDIOVASCULAR JOURNAL OF AFRICA • Volume 27, No 1, January/February 2016 16 AFRICA
Electrocardiographic abnormalities and dyslipidaemic
syndrome in children with sickle cell anaemia
Samuel Ademola Adegoke, John Akintunde Oladotun Okeniyi, Adeseye Abiodun Akintunde
Abstract
Background: Lipid and electrocardiographic (ECG) abnor-
malities have been reported in adults with sickle cell anaemia
(SCA) and may reflect underlying structural and/ or func-
tional damage. However, the relationship between ECG and
lipid abnormalities among children with sickle cell disease is
not fully understood.
Objectives: To compare the steady-state lipid and ECG abnor-
malities in children with SCA to the controls and examine the
hypothesis that lipid abnormalities are closely related to elec-
trocardiographic abnormalities, and therefore are a reflection
of cardiac damage among these children.
Methods: Clinical, laboratory and ECG profiles of 62 chil-
dren with SCA and 40 age- and gender-matched haemoglobin
AA controls were compared. The influence of clinical charac-
teristics, lipids profiles, markers of haemolysis, and renal and
hepatic dysfunction on ECG pattern in children with SCA
was then determined.
Results: The patients had lower average diastolic and mean
arterial blood pressure, total cholesterol and low-density
lipoprotein cholesterol (LDL-C) levels than the controls,
( p = 0.001, 0.002, 0.000 and 0.000, respectively). The mean
triglyceride level was significantly higher (p < 0.001), while
high-density lipoprotein cholesterol (HDL-C) levels were
comparable (p = 0.858). The cases were about six times more
likely to have left ventricular hypertrophy than the controls
(OR = 6.4, 95% CI = 2.7–15.6, p = 0.000). Haematocrit level
had a negative correlation with QTC (r = –0.3, p = 0.016) and
QT intervals (r = – 0.3, p = 0.044). Triglyceride levels had a
positive correlation with the PR interval (r = 0.3, p = 0.012),
while serum alanine transferase (ALT) concentrations had an
inverse correlation with PR interval (r = –0.3, p = 0.015). There
was no statistical difference in the sociodemographic and clini-
cal characteristics of the SCA children with or without ECG
abnormalities. However, the mean triglyceride and serum ALT
levels in those with ECG abnormalities were significantly
higher than those without (p = 0.007 and 0.045, respectively).
Conclusion: Lipid and ECG abnormalities are common in
children with SCA. Elevated triglyceride and serum ALT
levels are possible biochemical markers of ECG abnormali-
ties in these patients.
Keywords: children, dyslipidaemia, electrocardiogram, sickle cell
anaemia
Submitted 12/2/15, accepted 15/7/15
Published online 6/8/15
Cardiovasc J Afr 2016; 27: 16–20
DOI: 10.5830/CVJA-2015-059
Several specific and non-specific electrocardiographic
abnormalities have been reported in adult patients with sickle cell
anaemia (SCA).1-3 Left ventricular hypertrophy (LVH), the most
commonly reported ECG abnormality, has a prevalence ranging
from 50 to 75% among different study populations.3 Also,
significant prolongation of QRS duration, PR and QTC intervals,
P wave, QRS and QTC dispersions, as well as T-wave inversion in
the right precordial leads have been reported among Nigerian
adults with SCA. 1 Apart from the underlying pathologies, these
high-voltage recordings have been attributed to reduced skin fat
and thin chest wall in patients with sickle cell disease. 4
Dyslipidaemic syndrome, characterised by hypocholesterol-
aemia, hypertriglyceridaemia and reduced plasma high-density
lipoprotein cholesterol (HDL-C) levels, is a known metabolic
disorder in adults and children with SCA.5-7 Low total cholesterol
in SCA has been linked to chronic haemolysis and/or increased
erythropoesis, with a subsequent increase in cholesterol
utilisation.6 Plasma lipid levels have also been reported to
correlate well with biomarkers of vascular haemolysis such
as haematocrit level, haemoglobin concentration and lactate
dehydrogenase levels in children with SCA.8 However, the
influence of dyslipidaemic syndrome on the overall severity and
development of electrocardiographic (ECG) abnormalities in
children with sickle cell anaemia is not fully understood.
‘Nature’ and ‘nurture’ are known to influence SCA severity
and the development of complications.9 Some of these factors
include the patient’s environment; genetic modifiers, especially
β-globin gene haplotype and foetal haemoglobin levels; and
several other haematological and biochemical markers, including
serum lipids and lipoproteins. These markers, in addition to
determining the severity of SCA, also help to predict the possible
complications a patient with SCA may develop.9 Therefore, a
search for potential biomarkers of SCA disease severity would
contribute positively to overall SCA management.
In addition to comparing the steady-state lipid profiles of
children with SCA with suitable controls and determining the
prevalence of ECG abnormalities, this study examined the
hypothesis that lipids are potential biochemical markers of ECG
abnormalities in sickle cell disease. To achieve this, we related
the clinical, haematological and biochemical profiles, including
the steady-state lipid profiles, of children with SCA with their
ECG pattern.
Paediatric Haematology Unit, Department of Paediatrics and
Child Health, Obafemi Awolowo University, Ile-Ife, Nigeria
Samuel Ademola Adegoke, MB ChB, MPH, FWACP (Paed),
Paediatric Cardiology Unit, Department of Paediatrics and
Child Health, Obafemi Awolowo University, Ile-Ife, Nigeria
John Akintunde Oladotun Okeniyi, BSc, MB ChB, FWACP (Paed)
Cardiology Division, Department of Medicine, Ladoke
Akintola University of Technology, Ogbomoso, Nigeria
Adeseye Abiodun Akintunde, MB ChB, FWACP, FMCP