Chlamydia pneumoniae, antimicrobial therapy and coronary heart disease: a critical overview.

Traditional cardiovascular risk factors, such as smoking, hypercholesterolaemia and hypertension probably only explain about 50% of the prevalence and severity of coronary heart disease (CHD). The recent interest in the association between Chlamydia pneumoniae and the pathogenesis and progression of atherosclerotic diseases is based on several lines of evidence-seroepidemiological studies, pathological specimen examinations, laboratory-based experiments, animal models and more recently, pilot intervention trials with anti-chlamydial antibiotics (Table 1). Whether C. pneumoniae has a direct causal role in atherosclerosis (and its clinical sequelae), and whether antibiotics have a protective role in the secondary prevention of CHD remains unclear. The results from large scale, prospective antibiotic trials in CHD, currently in progress, should help to clarify these important issues.