Fluoroquinolones may reduce the risk of myocardial infarction

Antibiotic treatment for infections of Chlamydia pneumoniae has been associated with protection against myocardial infarction, probably via a stabilizing effect on the cytoskeleton of endothelial cells and on chondrocytes in humans. Dr Herings et al from the Netherlands decided to test this association through a case-control study to see whether patients receiving antibiotics for Chlamydia pneumoniae infections were less likely to have been admitted for a first acute MI (JAMA 2000 284:2998-2999).

They identified 628 patients, aged 35 to 75, admitted with a first hospitalization for MI, studied their drug history, and compared them to 1615 matched controls. Only intake of high doses of fluoroquinolones was significantly associated with a lower risk of acute myocardial infarction. For those who took more than one course of fluoroquinolones, the odds ratio was 0.12 (95% CI, 0.02-0.94). For all other antibiotics, in particular tetracyclines and macrolides, no significant association was observed.

The authors ...