The potential role of Chlamydia pneumoniae infection in the pathogenesis of atherosclerosis has received increasing attention. The present study was conducted to test the hypothesis that use of doxycycline in doses prescribed in routine clinical practice for brucellosis, decreases the risk of coronary artery disease (CAD).

A general practice (GP) database in Western Greece was used. One hundred and twenty-nine newly diagnosed patients with coronary artery disease from 2001 to 2003 were contrasted to 196 controls randomly selected from the same practice. General practice records were reviewed to confirm a diagnosis of incident CAD event and obtain information on other cardiovascular risk factors. CAD events were defined as: Stable/unstable angina, acute myocardial infarction or ischemic death.

The results indicate a significant association between doxycycline use and occurrence of CAD (OR: 0.37, 95% CI: 0.17–0.78).

These results persisted when adjustment for potential confounding factors was made. The findings should be interpreted cautiously because of lack of information about C. pneumoniae infection. However, the results suggest directions for future epidemiologic studies in this relatively uncharted field.