Antibiotic Treatment of Chlamydia pneumoniae after Acute Coronary Syndrome Christopher P. Cannon, M.D., Eugene Braunwald, M.D., Carolyn H. McCabe, B.S., J. Thomas Grayston, M.D., Brent Muhlestein, M.D., Robert P. Giugliano, M.D., Richard Cairns, M.Sc., Allan M. Skene, Ph.D. and the Pravastatin or Atorvastatin Evaluation and Infection Therapy-Thrombolysis in Myocardial Infarction 22 Investigators N Engl J Med Volume 352;16:1646-1654 April 21, 2005

Study Overview Studies have suggested that infection with Chlamydia pneumoniae may have a role in the pathogenesis of coronary artery disease This study casts doubt on the idea, since two years of treatment with gatifloxacin, an antibiotic with bactericidal activity against C pneumoniae, had no beneficial effect on clinical outcomes This study complements the results of the study by Grayston et al reported in this issue of the Journal, which led to a similar conclusion

Numbers of Patients Who Were Randomly Assigned to a Treatment Group, Who Started the Assigned Treatment, and Who Discontinued Treatment or Were Lost to Follow-up Cannon, C. et al. N Engl J Med 2005;352:1646-1654

Baseline Characteristics of the Patients Cannon, C. et al. N Engl J Med 2005;352:1646-1654

Kaplan-Meier Estimates of Events over Time among Patients Treated with Gatifloxacin or Placebo Cannon, C. et al. N Engl J Med 2005;352:1646-1654

Risk Reduction for Death or a Major Cardiovascular Event and Event Rates at Two Years Cannon, C. et al. N Engl J Med 2005;352:1646-1654

Hazard Ratios for Death or a Major Cardiovascular Event, with Two-Year Event Rates, According to Baseline Characteristics Cannon, C. et al. N Engl J Med 2005;352:1646-1654

Conclusions Despite long-term treatment with a bactericidal antibiotic effective against C pneumoniae, no reduction in the rate of cardiovascular events was observed