[Chronic Chlamydia pneumoniae infection in patients with coronary disease. Relation with increased fibrinogen values]

Abstract

Background: A number of studies have suggested that infection with Chlamydia pneumoniae can play a role in development of atherosclerosis. The goal of this study was to know the prevalence of chronic C. pneumoniae infection, evaluated with IgG antibodies seropositivity, in Spanish patients with coronary disease and its association with inflammatory markers and cardiovascular risk factors.

Patients and method: In 176 patients with coronary disease IgG and IgM antibodies to C. pneumoniae were determined by enzyme immunoassay. In addition, fibrinogen and C-reactive protein values were measured as inflammatory markers. Controls were 55 healthy subjects whose age was not different from patients. Seropositivity for C. pneumoniae was considered when indices of IgG and/or IgM antibodies were higher than mean plus two standard deviations of control values. Three patients with seropositivity for IgM were excluded.

Results: In 126 patients and 2 controls a seropositivity against C. pneumoniae was proved (72.8% vs 4.2%; p < 0.001). Cardiovascular risk factors were not different in seropositive and seronegative groups of patients. Prevalence of hyperfibrinogenemia was higher in the former group (38.8% vs 19.1%; p = 0.01). The number of the patients with increased values of C-reactive protein was similar in both groups, although these values could be modified by treatment with statins. In multivariate analysis an association between seropositivity for C. pneumoniae and hyperfibrinogenemia was found (odds ratio [OR] = 2.42; 95% confidence interval, 1.07-5.48; p = 0.03) after adjusting for age, gender, smoking, hypertension, hypercholesterolemia and diabetes.

Conclusions: Chronic infection with C. pneumoniae in patients with coronary disease is very prevalent, and it is associated with increased fibrinogen values.