HELICOBACTER-PYLORI INFECTION - RELATION WITH CARDIOVASCULAR RISK-FACTORS, ISCHEMIC-HEART-DISEASE, AND SOCIAL-CLASS

Objective-To determine whether Helicobacter pylori infection is associ ated with the development of ischaemic heart disease and whether such infection can explain the social class inequality in ischaemic heart d isease. Design-Cardiovascular risk factor levels, prevalence of ischae mic heart disease (Rose questionnaire angina, and/or a history of myoc ardial infarction), and serum antibodies to H pylori (enzyme linked im munosorbent 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 selecte d from the Central Services Agency's general practitioner lists. Main outcome measures-The relation of H pylori infection with cardiovascula r risk factors and ischaemic heart disease. The association of social class with ischaemic heart disease. Results-Systolic and diastolic blo od and total with H pylori infection. A weak negative association exis ted 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 lipopro tein (HDL) cholesterol (mean (SE) difference in HDL cholesterol betwee n 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 statistic al significance (odds ratio (95% confidence interval (CI) 1.51 (0.93 t o 2.45), P = 0.1). Social class was associated with ischaemic heart di sease independently of cardiovascular risk factors and H pylori infect ion (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 d evelopment 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.