Antibiotic treatment of Chlamydia pneumoniae after acute coronary syndrome.
BACKGROUND
Chlamydia pneumoniae has been found within atherosclerotic plaques, and elevated titers of antibody to this organism have been linked to a higher risk of coronary events. Pilot studies have suggested that antibiotic treatment may reduce the risk of cardiovascular events.


METHODS
We enrolled 4162 patients who had been hospitalized for an acute coronary syndrome within the preceding 10 days and evaluated the efficacy of long-term treatment with gatifloxacin, a bactericidal antibiotic known to be effective against C. pneumoniae, in a double-blind, randomized, placebo-controlled trial. Subjects received 400 mg of gatifloxacin daily during an initial 2-week course of therapy that began 2 weeks after randomization, followed by a 10-day course every month for the duration of the trial (mean duration, 2 years), or placebo. The primary end point was a composite of death from all causes, myocardial infarction, documented unstable angina requiring rehospitalization, revascularization (performed at least 30 days after randomization), and stroke.


RESULTS
A Kaplan-Meier analysis revealed that the rates of primary-end-point events at two years were 23.7 percent in the gatifloxacin group and 25.1 percent in the placebo group (hazard ratio, 0.95; 95 percent confidence interval, 0.84 to 1.08; P=0.41). No benefit was seen in any of the prespecified secondary end points or in any of the prespecified subgroups, including patients with elevated titers to C. pneumoniae or C-reactive protein.


CONCLUSIONS
Despite long-term treatment with a bactericidal antibiotic effective against C. pneumoniae, no reduction in the rate of cardiovascular events was observed.
Cannon
Christopher P
CP
Thrombolysis in Myocardial Infarction Study Group, Cardiovascular Division, Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, MA 02115, USA. cpcannon@partners.org
Braunwald
Eugene
E
McCabe
Carolyn H
CH
Grayston
J Thomas
JT
Muhlestein
Brent
B
Giugliano
Robert P
RP
Cairns
Richard
R
Skene
Allan M
AM
D000368:Aged; D000789:Angina, Unstable / Q000188:drug therapy* / Q000517:prevention & control; D000900:Anti-Bacterial Agents / Q000009:adverse effects / Q000627:therapeutic use*; D002318:Cardiovascular Diseases / Q000401:mortality / Q000517:prevention & control*; D023521:Chlamydophila Infections / Q000188:drug therapy*; D016993:Chlamydophila pneumoniae; D004311:Double-Blind Method; D005260:Female; D024841:Fluoroquinolones / Q000009:adverse effects / Q000627:therapeutic use*; D000077734:Gatifloxacin; D006801:Humans; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000188:drug therapy* / Q000517:prevention & control; D009204:Myocardial Revascularization; D016016:Proportional Hazards Models; D011446:Prospective Studies; D020521:Stroke / Q000517:prevention & control
D000900:Anti-Bacterial Agents; D024841:Fluoroquinolones; D000077734:Gatifloxacin