Objectives: To study antibodies against five infectious agents for their prediction of major coronary events in men with and without evidence of coronary heart disease at baseline.
Design: A case-control study nested within a prospective population study.
Subjects: The study cases included 441 men 45-64 years old with nonfatal myocardial infarction or coronary death within a mean follow-up time of 10 years. A total of 165 men had already signs of heart disease at baseline, whilst 276 were apparently healthy at the beginning of the study. Two controls for each case were matched for age, heart disease status and place of residence. Antibodies against enterovirus, Mycoplasma pneumoniae, Chlamydia pneumoniae, cytomegalovirus and adenovirus were determined.
Results: Men without reported baseline heart disease, but not those with heart disease, showing the highest quartile of antibodies to enterovirus and mycoplasma or increased levels of immune complex-bound antibodies to chlamydia had a significantly higher risk of coronary events than men with lower level of antibodies. The increased risk demonstrated in men with high levels of antibodies to enterovirus and mycoplasma remained significant after adjustment for other antibodies, acute-phase reactant and conventional risk factors. Serological evidence of infection by multiple agents was also significantly associated with coronary events.
Conclusions: Serological evidence for several infectious agents is associated with the risk of coronary heart disease, but only in men without baseline history of heart disease.