Relation of Helicobacter pylori infection and coronary heart disease.

BACKGROUND--There is evidence suggesting that early life experience may influence adult risk of coronary heart disease (CHD). Chronic bacterial infections have been associated with CHD. OBJECTIVE--To determine whether Helicobacter pylori, a childhood acquired chronic bacterial infection, is associated with an increased risk of coronary heart disease in later life. DESIGN--Case-control study controlling for potential confounding variables with an opportunistically recruited control group. SUBJECTS--111 consecutive cases with documented CHD were recruited from a cardiology clinic and 74 controls from a general practice health screening clinic. All were white men aged 45-65. METHODS--Serum was analysed for the presence of H pylori specific IgG antibodies by ELISA (98% sensitive and 94% specific for the presence of infection). RESULTS--59% of the cases and 39% of the controls were seropositive for H pylori (odds ratio 2.28, chi 2 7.35, p = 0.007). After adjustment by multiple logistic regression for age, cardiovascular risk factors, and current social class, the effect of H pylori was little altered (odds ratio 2.15, p = 0.03). Further adjustment for various features of the childhood environment known to be risk factors for H pylori infection only slightly weakened the association (odds ratio 1.9). H pylori seropositivity was not related to the level of risk factors in the control population. CONCLUSION--In this pilot study the association of adult coronary heart disease with H pylori seropositivity suggests that the early childhood environment may be important in determining the risk of CHD in adult life. The association needs confirmation in other better designed studies. If H pylori itself is responsible for the association, then this is of great potential importance as the infection is treatable

Prospective relations between Helicobacter pylori infection, coronary heart disease and stroke in middle-aged men

OBJECTIVE: To determine whether Helicobacter pylori, a chronic bacterial infection often acquired in childhood, is associated with increased risk of coronary heart disease and stroke later in life. DESIGN: Nested case-control study. SETTING: Prospective study of cardiovascular disease in men aged 40-59 years at entry (1978-1980) in 24 British towns. SUBJECTS: 135 cases of myocardial infarction and 137 cases of stroke occurring before December 1991; 136 controls were identified, frequency matched to cases by town and age group. METHODS: Serum samples stored at entry were analysed by an enzyme linked immunosorbent assay for the presence of H pylori specific IgG antibodies. RESULTS: 95 of the myocardial infarction cases (70%) and 93 (68%) of the stroke cases were seropositive for H pylori compared with 78 (57%) of the controls (odds ratio for myocardial infarction 1.77, 95% confidence interval (CI) 1.06 to 2.95, P = 0.03; odds ratio for stroke 1.57, 95% CI 0.95 to 2.60, P = 0.07). Helicobacter pylori infection was associated with manual social class, residence in Northern England or Scotland, cigarette smoking, higher systolic pressure and blood glucose, and a lower height-standardised forced expiratory volume in one second. Adjustment for these factors attenuated the relation between H pylori and myocardial infarction (odds ratio = 1.31, 95% CI 0.70 to 2.43, P = 0.40) and effectively abolished the relation with stroke (odds ratio = 0.96, 0.46 to 2.02, P = 0.92). The relation between helicobacter infection and fatal myocardial infarction was slightly stronger (odds ratio 2.41, 95% CI 1.13 to 5.12) but was also markedly attenuated after adjustment (1.56, 95% CI 0.68 to 3.61). CONCLUSION: In this prospective study the association between Helicobacter pylori infection and increased risk of myocardial infarction and stroke was substantially confounded by the relation between this infection, adult social class, and major cardiovascular risk factors

Helicobacter pylori infection: relation with cardiovascular risk factors, ischaemic heart disease, and social class.

OBJECTIVE--To determine whether Helicobacter pylori infection is associated with the development of ischaemic heart disease and whether such infection can explain the social class inequality in ischaemic heart disease. DESIGN--Cardiovascular risk factor levels, prevalence of ischaemic heart disease (Rose questionnaire angina, and/or a history of myocardial infarction), and serum antibodies to H pylori (enzyme linked immunosorbent assay) were assessed in a cross sectional population based survey. SETTING--Belfast and surrounding districts, Northern Ireland. PARTICIPANTS--1182 men and 1198 women aged 25-64 years randomly selected from the Central Services Agency's general practitioner lists. MAIN OUTCOME MEASURES--The relation of H pylori infection with cardiovascular risk factors and ischaemic heart disease. The association of social class with ischaemic heart disease. RESULTS--Systolic and diastolic blood pressure, plasma viscosity, and total cholesterol were not associated with H pylori infection. A weak negative association existed between H pylori infection and fibrinogen (mean (SE) difference in fibrinogen between infected and uninfected individuals -0.09 (0.04) g/l, P = 0.02) and between infection in women and high density lipoprotein (HDL) cholesterol (mean (SE) difference in HDL cholesterol between infected and uninfected individuals -0.06 (0.02) mmol/l, P = 0.006). A potentially important association was demonstrated between H pylori infection and ischaemic heart disease but this did not reach statistical significance (odds ratio (95% confidence interval (CI) 1.51 (0.93 to 2.45), P = 0.1). Social class was associated with ischaemic heart disease independently of cardiovascular risk factors and H pylori infection (odds ratio, manual v non-manual (95% CI) 1.82 (1.14 to 2.91), P = 0.01). CONCLUSION--H pylori may be independently associated with the development of ischaemic heart disease but if this is so the mechanism by which this effect is exerted is not through increased concentration of plasma fibrinogen. H pylori infection does not explain the social class inequality in ischaemic heart disease which exists independently of known cardiovascular risk factors