CARDIOVASCULAR JOURNAL OF AFRICA • Vol 23, No 3, April 2012
AFRICA
131
Prognostic role of
Helicobacter pylori
infection in acute
coronary syndrome: a prospective cohort study
R ESKANDARIAN, R GHORBANI, M SHIYASI, B MOMENI, K HAJIFATHALIAN, M MADANI
Abstract
In a prospective cohort study, we evaluated the effect of
Helicobacter pylori
seropositivity on the risk of future adverse
cardiovascular outcomes among patients with acute coronary
syndrome (ACS). In 433 patients, IgA and IgG antibodies to
H pylori
, along with classic risk factors, including hyperten-
sion, diabetes, hyperlipidaemia, smoking and family history
of coronary artery disease (CAD) were determined. Short-
and long-term follow-up information on adverse outcomes,
defined as recurrence of unstable angina, myocardial infarc-
tion, coronary angioplasty, coronary artery bypass graft
surgery, and sudden cardiac death was obtained. None of the
classic CAD risk factors correlated with incidence of either
short- or long-term outcomes. Seropositivity for
H pylori
was significantly associated with risk of short-term adverse
outcomes, and independently predicted their incidence in
multivariate regression (
R
= 3.05,
p
< 0.001). Results failed to
show such an association between
H pylori
seropositivity and
long-term adverse outcomes.
H pylori
infection may affect
short-term prognosis in patients with ACS. Randomised
trials are needed to evaluate the role of
H pylori
eradication
in these patients.
Keywords:
H pylori
, acute coronary syndrome, prognosis
Submitted 8/11/10, accepted 15/4/11
Cardiovasc J Afr
2012;
23
: 131–135
DOI: 10.5830/CVJA-2011-016
Coronary artery disease (CAD) is the leading cause of death in
developed and transitioning countries.
1
Classic CAD risk factors,
such as dyslipidaemia, hypertension, smoking, family history of
CAD, and diabetes mellitus have not been able to fully explain
the variations in CAD incidence, morbidity and mortality,
2,3
and
there is a need to search for possible new causal mechanisms
affecting pathogenesis and prognosis of CAD.
4
Certain bacterial and viral pathogens have been suggested to
play a role in development and/or prognosis of CAD, including
Chlamydia pneumonia
,
Helicobacter pylori
, cytomegalovirus,
Coxsackie virus, Hepatitis A virus and
Herpes simplex
virus.
5-7
Numerous studies, mostly cross-sectional or case-control studies,
have assessed the association between
H pylori
infection and
CAD.
8-11
Various mechanisms have been proposed to explain the
role of
H pylori
infection in the pathogenesis of CAD, namely
causing persistent local or systemic inflammation, and initiating
autoimmune responses.
12,13
However, studies provide discordant
data on the association between
H pylori
infection and CAD.
While some studies report a significant relationship between
the two,
14-18
others suggest no, or at best a weak association
between
H pylori
infection and CAD.
19-23
As a result of this
discrepancy, the actual role of
H pylori
in the pathogenesis
and prognosis of CAD has remained largely controversial,
24-26
and many authors suggest well-designed prospective studies to
further investigate the association between
H pylori
and CAD.
27,28
Moreover,
H pylori
diagnosis is fairly simple and its treatment
much easier and less costly, compared to that of classic CAD
risk factors.
4
Therefore finding a causal relationship between
H
pylori
infection and prognosis in patients with CAD, especially
patients presenting with acute coronary syndrome (ACS), may
enable clinicians to decrease morbidity and mortality simply by
treating
H pylori
infection in these patients.
18
In the light of this, the present study was designed as
a prospective cohort to investigate the effect of current
H
pylori
infection on short- and long-term prognosis in patients
presenting with ACS. The results of this study will help to
clarify the relationship between
H pylori
infection and CAD. In
addition, it will provide information regarding the possible role
of
H pylori
eradication in patients presenting with ACS.
Methods
This was a prospective cohort study carried out at the Fatemieh
Hospital, Semnan, Iran. Between January 2004 and November
2006, a total of 450 patients admitted for ACS to the emergency
ward or critical care unit agreed to participate in the study
and were enrolled. Patient selection was done by the census
sampling method. The objective and necessary procedures were
clearly explained to these patients and all participants provided
informed written consent before enrollment. The study was
approved by the medical ethics committee of the hospital.
ACS (inclusion criteria) was defined as presenting with either
unstable angina (clinical diagnosis) or myocardial infarction
(MI), defined as significant ST elevation or new left bundle
branch block in electrocardiography or increased levels of
cardiac enzymes. During the one-year follow-up period, 17
participants were excluded from the study due to either receiving
treatment for
H pylori
infection or becoming unavailable for
follow up.
Risk factors evaluated in this study were: hypertension,
diabetes mellitus (DM), hyperlipidaemia, cigarette smoking,
and family history of CAD. Hypertension was defined as
arterial blood pressure
≥
140/90 mmHg or being treated with
antihypertensive drugs. DM was defined as fasting blood sugar
levels
≥
126 mg/dl or being treated for this diagnosis with either
diet or medication. Hyperlipidaemia was defined as low-density
lipoprotein (LDL) cholesterol levels
≥
130 mg/dl or being treated
Department of Cardiology, Faculty of Medicine, Seman
University of Medical Sciences, Semnan, Iran
R ESKANDARIAN, MD
M MADANI, MD,
Department of Community Medicine, Faculty of Medicine,
Semnan University of Medical Sciences, Semnan, Iran
R GHORBANI, PhD
M SHIYASI, MD
B MOMENI, MD
K HAJIFATHALIAN, MD
