(Circulation. 2000;101:1647.)
© 2000 American Heart Association, Inc.
Clinical Investigation and Reports |
From the Department of Population Sciences and Primary Care (P.W., M.W., L.L., A.T.), Royal Free UCL Medical School, London, UK; the Clinical Trial Service Unit and Epidemiological Studies Unit (J.D.), University of Oxford, Oxford, UK; ICRF Cancer Epidemiology Unit (P.A.), Oxford, UK; and the Division of Gastroenterology and Institute of Infections and Immunity (C.H., J.A.), University of Nottingham, Nottingham, UK.
Correspondence to Dr Peter Whincup, Department of Public Health Sciences, St Georges Hospital Medical School, Cranmer Terrace, London SW17 ORE, UK. E-mail p.whincup{at}sghms.ac.uk
| Abstract |
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Methods and ResultsWe measured serum IgG antibodies to mixed H pylori antigens and separately to the virulence-associated H pylori antigen CagA (cytotoxin-associated gene product A) in 505 CHD cases and in 1025 age-matched controls "nested" in a prospective study of 7735 British men (mean duration of follow-up in controls, 16 years). Of the 505 cases, 401 (79%) were seropositive for H pylori antibodies compared with 740 (72%) of the 1025 controls, yielding an odds ratio for CHD of 1.55 (95% CI 1.19 to 2.03), which fell to 1.30 (95% CI 0.88 to 1.90) after adjustments were made for standard vascular risk factors and indicators of socioeconomic status. Of the CHD cases, 240 (48%) were seropositive for IgG antibodies to CagA compared with 450 (44%) of the controls. When CagA-seropositive individuals were compared with H pyloriseronegative individuals, the odds ratio for CHD was 1.42 (95% CI 1.06 to 1.91), which fell to 1.10 (95% CI 0.71 to 1.71) after adjustments. In an analysis restricted to the 1141 (75%) H pyloriseropositive participants, the odds ratio for CHD was 1.0 (95% CI 0.78 to 1.29) in CagAseropositive men. No strong associations were observed between H pylori seropositivity and blood lipids, blood pressure, markers of systemic inflammation, or plasma homocysteine.
ConclusionsH pylori infection is not strongly related to the incidence of CHD in late middle-aged men, and CagA-positive strains appear to be no more strongly related to the disease than other strains. However, further studies are required to confirm or refute the existence of any moderate associations, particularly at younger ages.
Key Words: coronary disease epidemiology infection men
| Introduction |
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| Methods |
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Laboratory Methods
H pylorispecific IgG titers were measured by
laboratory workers unaware of the case-control status of blood samples
in December 1998. An ELISA kit (Premier, Meridian
Diagnostics) was used, and the intra-assay and interassay
coefficients of variation were 3% and 6%, respectively. Anti-CagA
serum antibodies were measured by ELISA with the use of a recombinant
CagA antigen (orv200, a gift from Orovax Inc, Cambridge, Mass),
according to a method described previously.3 This
assay had 92% (34 of 37 patients) sensitivity and 96% (24 of 25
patients) specificity in 62 patients in another study in whom CagA
status was directly assessed by commercial Western blot in gastric
biopsy specimens (Helicoblot 2.0, Genelabs Diagnostics).
Measurements were made of serum lipids, albumin, leukocyte
count, and hematocrit by use of standard assays soon after the baseline
blood collection; measurements were made of C-reactive protein and
serum amyloid A by use of sensitive enzyme immunoassays in stored
samples.9
Statistical Methods
Case-control comparisons involved unmatched stratified logistic
regression fitted by unconditional maximum likelihood (Stata Corp).
Adjusted analyses included the following (as explanatory
variables): age; cigarette smoking habit (never, former, or
current); daily cigarette consumption; nonfasting blood concentrations
of total cholesterol, HDL cholesterol, and
triglycerides; systolic and diastolic
blood pressures; current social class (according to the Registrar
Generals 1980 classification and including a separate category for
armed forces8 ); housing tenure (owner, private rent, or
council rent); marital status; current car ownership; and childhood
social circumstances (eg, fathers occupation, family car ownership,
bathroom in house, hot water tap in house, and bedroom sharing).
Concentrations of blood lipids and a number of other blood components
were also investigated as possible correlates of H pylori
seropositivity. Emphasis was mainly given to differences more extreme
than 2.6 standard deviations (2P
0.01) to make some
allowance for multiple comparisons. Methods to identify studies for an
updated meta-analysis of prospective studies published before
1999 involving H pylori IgG serology and CHD have been
described previously.1 2 Combination of results
involved inverse-varianceweighted averages of log odds ratios.
Heterogeneity was assessed by standard
2 tests. Odds ratios are given with 95%
confidence limits, and 2-sided probability (2P) values are
used.
| Results |
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Of the 505 CHD cases, 401 (79%) were seropositive for H
pylori IgG antibodies compared with 740 (72%) of the 1025
controls (Table 3
). This
difference yielded an age- and town-adjusted odds ratio for CHD of 1.55
(95% CI 1.19 to 2.03;
2=10.4,
2P=0.001), which fell to 1.30 (95% CI 0.88 to 1.90;
2=1.5, 2P>0.1) after additional
adjustments for smoking, blood lipids, blood pressure, and both adult
and childhood indicators of socioeconomic status. Varying the cutoff
titer around the manufacturers recommended level did not materially
alter the estimates. Of the 505 CHD cases, 240 (48%) were seropositive
for IgG antibodies to CagA compared with 450 (44%) of the controls
(Table 3
). In a comparison of CagA-seropositive individuals with
those who were H pylori seronegative, the odds ratio for CHD
was 1.42 (95% CI 1.06 to 1.91;
2=5.7,
2P=0.02), which fell to 1.10 (95% CI 0.71 to 1.71;
2=0.1, 2P>0.1) after adjustments.
When attention was restricted to only those 1141 (75%) participants
who were H pylori seropositive, 240 (60%) of 401 such cases
and 450 (60%) of 740 such controls were also CagA seropositive,
yielding an odds ratio for CHD of 1.0 (95% CI 0.78 to 1.29). These
results were not materially changed when the analyses were
restricted to the 328 cases and 820 controls with no evidence of CHD at
baseline (Table 3
) or when the analyses were restricted
to the 227 cases and 779 controls who had complete information on all
reported markers of childhood socioeconomic status. The data were too
sparse to subdivide reliably by potentially relevant characteristics,
such as age and nonfatal versus fatal CHD.
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| Discussion |
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CHD and H pylori Infection
Large prospective studies of H pylori and CHD should be
more informative than small retrospective studies because they avoid
selection biases, assess infection before the onset of clinical
disease, and generally record more information on possible
confounders and/or mediators.1 The present study
involves 505 CHD cases and is larger than all but one10 of
the 6 previously reported prospective studies involving H
pylori and CHD death or MI.8 10 11 12 13 14 In
aggregate, these 7 reports involve a total of 2286 CHD cases. All made
adjustment for smoking and other standard vascular risk factors, but
only 5 (including the present study) adjusted for markers of
socioeconomic status.8 10 11 12 The weighted mean age at CHD
event was 67 years (ie, weighted mean age at baseline of 54 years with
a weighted mean follow-up of 13 years). There was no evidence of
heterogeneity between the 7 studies
(
26=4.2, P>0.1),
and a combined analysis of their results yielded an adjusted
risk ratio of 1.16 (95% CI 0.94 to 1.43,
Figure
). Hence, at least in older individuals
with CHD, it seems unlikely that H pylori is strongly
related to disease. Because relative risks for standard vascular risk
factors tend to be greater in early middle age than at older ages,
studies of early-onset CHD may be more sensitive to the existence of
any modest association. Indeed, the odds of MI were about twice as
great in people seropositive for antibodies to H pylori
(adjusted odds ratio 1.87, 95% CI 1.52 to 2.32) in a study of 1122
early-onset cases (average age 44 years) and 1122 age- and sex-matched
controls.15
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CHD and Potentially Virulent Strains of H
pylori
In the only previously published study, an adjusted odds ratio of
3.8 (95% CI 1.6 to 9.1) was reported for CHD in CagA-seropositive
individuals.5 This result, however, was based on only 88
cases (34 MI cases and 54 cases of angina), involved very wide CIs, and
was especially susceptible to the play of chance (because it was a
hypothesis-generating finding). Selection biases were also possible
because the controls were blood donors who may not have been truly
comparable to the cases. By contrast, the present study involves
>5 times as many CHD cases as the previous report. It avoids selection
biases because cases and controls were selected within the same
contemporaneous cohort of men and because blood samples were collected
several years before the diagnosis of disease. We observed no strong
association between CagA seropositivity and CHD (adjusted odds ratio
1.10, 95% CI 0.71 to 1.71), and the adjusted odds ratio was similarly
null (odds ratio 1.0, 95% CI 0.78 to 1.29) when comparisons of CagA
seropositivity were restricted to only the 1141 (75%) individuals who
were H pylori seropositive. It seems unlikely, therefore,
that CagA-seropositive strains of H pylori are much more
strongly related to CHD than are other strains.
H pylori Seropositivity, Vascular Risk Factors, and
Other Characteristics
It has been suggested that H pylori infection is
importantly related to levels of various known risk factors, such as
blood lipids or fibrinogen.16 However, a
meta-analysis of 18 reports involving a total of 10 000
individuals found no strong correlations of H pylori
seropositivity with blood total cholesterol,
triglycerides, fibrinogen, blood pressure, C-reactive
protein, or leukocyte count,17 nor did the
present study in 1500 individuals. The present report extends
these observations by suggesting no strong associations of H
pylori seropositivity with additional suspected risk factors, such
as plasma homocysteine, serum amyloid A protein, insulin, hematocrit,
and markers of renal function.
Conclusions
H pylori infection is not strongly related to the
incidence of CHD in late middle age, and CagA-positive strains appear
no more strongly related to the disease than other strains. Further
studies may be needed, however, to confirm or refute the existence of
any modest associations, particularly at younger ages.
| Acknowledgments |
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Received July 21, 1999; revision received October 28, 1999; accepted November 10, 1999.
| References |
|---|
|
|
|---|
2. Danesh J, Appleby P. Persistent infection and vascular disease: a systematic review. Expert Opin Invest Drugs. 1998;7:691713.
3.
Blaser MJ, Perez-Perez GI, Kleanthous H.
Infection with Helicobacter pylori strains possessing cagA
is associated with an increased risk of developing adenocarcinoma of
the stomach. Cancer Res. 1995;55:21112115.
4.
Atherton JC. H pylori virulence
factors. Br Med Bull. 1998;54:105120.
5.
Pasceri V, Cammarota G, Patti G, Cuoco L,
Gasbarrini A, Grillo RL, Fedeli G, Gasbarrini G, Maseri A. Association
of virulent Helicobacter pylori strains with
ischemic heart disease. Circulation. 1998;97:16751679.
6. Shaper AG, Pocock SJ, Walker M, Cohen NM, Wale CJ, Thomson AG. British Regional Heart Study: cardiovascular risk factors in middle-aged men in 24 towns. BMJ. 1981;283:179186.
7. Walker M, Shaper AG. Follow-up of subjects in prospective studies based in general practice. J R Coll Gen Pract. 1984;34:365370.[Medline] [Order article via Infotrieve]
8.
Whincup PH, Mendall MA, Perry IJ, Strachan DP,
Walker M. Prospective relations between Helicobacter pylori
infection, coronary heart disease, and stroke in middle-aged
men. Heart. 1996;75:568572.
9.
Danesh J, Muir J, Wong Y-K, Ward M, Gallimore R,
Pepys MB. Risk factors for coronary heart disease and
acute-phase proteins: population-based study. Eur Heart
J. 1999;20:954959.
10.
Wald NJ, Law MR, Morris JK, Bagnall AM.
Helicobacter pylori infection and mortality from ischaemic
heart disease: negative result from a large, prospective study.
BMJ. 1997;315:11991201.
11.
Strachan DP, Mendall MA, Carrington D, Butland
BK, Yarnell JWG, Sweetnam PM, Elwood PC. Relation of Helicobacter
pylori infection to 13-year mortality and incident
ischemic heart disease in the Caerphilly prospective heart
disease study. Circulation. 1998;98:12861290.
12. Ossewaarde JM, Feskens EJ, De Vries A, Vallinge CE, Kromhout D. Chlamydia pneumoniae is a risk factor for coronary heart disease in symptom-free elderly men, but Helicobacter pylori and cytomegalovirus are not. Epidemiol Infect. 1998;120:9399.[Medline] [Order article via Infotrieve]
13. Aromaa A, Knekt P, Reunanen A, Rautelin HI, Kosunen TU. Helicobacter pylori and the risk of myocardial infarction. Gut. 1996;39(suppl 2):A91. Abstract.
14.
Folsom AR, Nieto FJ, Sorlie P, Chambless LE,
Graham DY. Helicobacter pylori seropositivity and
coronary heart disease incidence. Circulation. 1998;98:845850.
15.
Danesh J, Youngman L, Clark S, Parish S, Peto R,
Collins R. Helicobacter pylori and early onset myocardial
infarction: case-control and sibling pairs study. BMJ. 1999;319:11571162.
16.
Patel P, Mendall MA, Carrington D, Strachan DP,
Leatham E, Molineaux N, Levy J, Blakeston C, Seymour CA, Camm AJ,
Northfield TC. Association of Helicobacter pylori and
Chlamydia pneumoniae infections with coronary heart
disease and cardiovascular risk factors.
BMJ. 1995;311:711714.
17.
Danesh J, Peto R. Risk factors for
coronary heart disease and infection with Helicobacter
pylori: meta-analysis of 18 studies. BMJ. 1998;316:11301132.
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