[Relationship of Chlamydia pneumoniae infection to severity of coronary atherosclerosis in patients with chronic coronary artery disease and with normal coronary arteries].

OBJECTIVES

Recent studies have demonstrated an association between infection with Chlamydia (C.) pneumoniae and coronary artery disease. However, the association is less clear in the Japanese population. The relationship of C. pneumoniae infection to severity of coronary atherosclerosis was investigated in patients with chronic coronary artery disease and with normal coronary arteries.

METHODS

Serum levels of IgA and IgG antibodies to C. pneumoniae outer membrane complex were measured by enzyme-linked immunosorbent assay and C-reactive protein (CRP) analyses in 130 patients who underwent coronary angiography. Patients with unstable angina and recent myocardial infarction were excluded. Results were divided into three groups according to Gensini coronary score (GCS): normal (n = 19, GCS = 0); mild atherosclerosis (n = 56, GCS = 1-19); and severe atherosclerosis (n = 55, GCS > or = 20).

RESULTS

Cut off indices of IgA and IgG in the atherosclerosis groups (severe: 1.53 +/- 0.72 and 1.67 +/- 0.97, mild: 1.58 +/- 0.92 and 1.42 +/- 0.86, respectively) were higher than in the normal group (1.22 +/- 0.59 and 1.28 +/- 0.82), but there were no significant differences. There were no correlations between indices of IgA and IgG, and GCS. The normal CRP group (n = 118, < 0.3 mg/dl) and the high CRP group (n = 12, > or = 0.3 mg/dl) showed no differences in IgA and IgG indices and GCS.

CONCLUSIONS

Serum antibody indices against C. pneumoniae are not associated with the severity of coronary atherosclerosis in chronic stable coronary artery disease.