Helicobacter pylori infection and mortality from ischaemic heart disease: negative result from a large, prospective study

Abstract

Objective—To determine whether there is an independent association between Helicobacter pylori infection of the stomach and ischaemic heart disease. Design—Prospective study with measurement of IgG antibody titres specific to H pylori on stored serum samples from 648 men who died from ischaemic heart disease and 1296 age matched controls who did not (nested case-control design). Subjects—21 520 professional men aged 35–64 who attended the British United Provident Association (BUPA) medical centre in London between 1975 and 1982 for routine medical examination. Main outcome measure—Death from ischaemic heart disease. Results—The odds of death from ischaemic heart disease in men with H pylori infection relative to that in men without infection was 1.06 (95% confidence interval 0.86 to1.31). In a separate group of 206 people attending the centre, plasma fibrinogen was virtually the same in those who were positive for H pylori (2.62 g/l) and those who were negative (2.64 g/l). Conclusions—A study that by its size and design minimised both random error and socioeconomic bias found no relation between H pylori infection and ischaemic heart disease. The validity of the study was shown by its confirmation of the recognised association between H pylori infection and stomach cancer (odds ratio 4.0 (1.9 to 8.2); PH pylori infection may greatly reduce the incidence of stomach cancer, one of the most common causes of death from cancer worldwide, but it cannot be expected to have any effect in preventing ischaemic heart disease. A cohort study found no association between Helicobacter pylori infection and death from ischaemic heart disease The study is much the largest to report on the association, with 648 deaths from ischaemic heart disease in men An important source of confounding which may have led to positive results in previous studies was avoided because all the subjects were of similar socioeconomic status The validity of the study was demonstrated by its ability to show the recognised association between H pylori infection and stomach cancer Men with H pylori infection had no increase in plasma fibrinogen (a proposed mechanism for infection causing heart disease) The study indicates that H pylori infection is not a cause of ischaemic heart disease