Serum chlamydial lipopolysaccharide as a prognostic factor for a new cardiovascular event.
BACKGROUND
Infections caused by Chlamydia pneumoniae are considered to participate in inflammatory processes leading to coronary artery disease. After a primary infection, the bacteria remain dormant intracellularly causing a chronic inflammatory stimulus.


METHODS
Blood samples were obtained from 235 patients with acute myocardial infarction (AMI) and 108 patients with unstable angina pectoris (UA). We evaluated the prognostic significance of bacterial and viral antibody titers, serum troponin T, C-reactive protein, and chlamydial lipopolysaccharide (cLPS) concentrations during acute coronary syndrome of patients with AMI and UA for cardiovascular death and new UA and AMI that required hospital care during a 6-year follow-up.


RESULTS
Serum cLPS levels correlated with C-reactive protein and serum troponin T concentrations during acute coronary events. Patients with AMI had significantly higher serum concentration of cLPS compared with patients with UA. Enterovirus antibody titers and cholesterol-lowering therapy at admission of the index event were negatively correlated with cLPS concentration (r = -.198, P = .0003 and r = -.26, P = .019, respectively). The presence of circulating cLPS was associated with a hazard ratio of 2.04 for a new cardiovascular event during the follow-up period (P = .006). The area under the curve in the receiver operating graph was .572.


CONCLUSIONS
cLPS is evidently liberated from the infected atherosclerotic tissue during an acute coronary event. Our study supports the view that inflammation caused by C. pneumoniae infection is an important but as yet poorly understood factor in the development of atherosclerosis and may play a role in acute vascular events.
Pesonen
Erkki
E
Pediatric Cardiology, University Hospital of Lund, Getingevägen 4, Lund SE-221 85, Sweden.
Tiirola
Terttu
T
Andsberg
Eeva
E
Jauhiainen
Matti
M
Paldanius
Matti
M
Persson
Kenneth
K
Saikku
Pekka
P
Sarna
Seppo
S
Ohlin
Hans
H
Leinonen
Maija
M
D000789:Angina, Unstable / Q000097:blood / Q000209:etiology* / Q000382:microbiology; D002097:C-Reactive Protein; D002690:Chlamydia Infections / Q000150:complications* / Q000382:microbiology; D016993:Chlamydophila pneumoniae / Q000302:isolation & purification*; D016001:Confidence Intervals; D003324:Coronary Artery Disease / Q000097:blood / Q000209:etiology / Q000382:microbiology; D018450:Disease Progression; D006801:Humans; D007249:Inflammation / Q000209:etiology* / Q000382:microbiology; D008070:Lipopolysaccharides / Q000032:analysis / Q000097:blood*; D011379:Prognosis; D016016:Proportional Hazards Models; D011446:Prospective Studies; D012307:Risk Factors
D008070:Lipopolysaccharides; D002097:C-Reactive Protein