title: Possible role of chronic infection with Chlamydia pneumoniae in Japanese patients with acute myocardial infarction.
abstract: Chlamydia pneumoniae, a common human respiratory pathogen, has been implicated in the pathogenesis of coronary heart diseases (CHD) in several seroepidemiological studies. The present case-control study investigated the relation between serologic evidence of C. pneumoniae infection and CHD in a Japanese population. Two groups of cases were enrolled: 26 patients with acute myocardial infarction (AMI) and 46 patients with effort angina pectoris (e-AP). Their data were compared with 58 age-matched healthy controls and also compared with 53 patients with vasospastic angina (VSA) as pathological control subjects. Anti-C. pneumoniae specific IgA and IgG antibody titers were measured by enzyme-linked immunosorbent assay (ELISA). The mean indices of IgG-type antibody in AMI and e-AP were not significantly different from those in either the normal controls or VSA group. On the other hand, the mean indices of IgA-type antibody in AMI were significantly higher than in the normal controls (1.39+/-0.83 in AMI vs 0.84+/-0.58 in controls, p<0.001) and VSA (1.39+/-0.83 in AMI vs 1.05+/-0.61 in VSA, p<0.05) group. However, the differences in the IgA titers in the e-AP group compared with the normal controls did not reach a significant level. The odds ratio associated with the seropositivity of IgA for AMI against the normal controls was 3.89 (95% confidence interval (CI): 1.16-13.10) and that against VSA was 6.90 (95% CI: 1.73-27.52) after adjustment for risk factors for CHD and/or age, sex and smoking status. In 6 patients the elevated IgA titers were sustained even at 3 months after the episode of AMI. These results suggest that seropositivity for IgA-type antibody against C. pneumoniae may be a significant risk factor for the development of AMI. The possible mechanisms include chronic inflammation in the coronary artery due to persistent C. pneumoniae infection.
authors: Department of Clinical Sciences and Laboratory Medicine, Kansai Medical University, Osaka, Japan.
authors: C
authors: C
authors: Kosaka
authors: K
authors: K
authors: Hara
authors: Y
authors: Y
authors: Komiyama
authors: H
authors: H
authors: Takahashi
mesh_terms: D000368:Aged; D000787:Angina Pectoris / Q000453:epidemiology / Q000209:etiology / Q000382:microbiology; D000907:Antibodies, Bacterial / Q000097:blood; D016022:Case-Control Studies; D002690:Chlamydia Infections / Q000150:complications* / Q000453:epidemiology; D016993:Chlamydophila pneumoniae / Q000276:immunology / Q000472:pathogenicity*; D002908:Chronic Disease; D015897:Comorbidity; D003289:Convalescence; D003920:Diabetes Mellitus / Q000453:epidemiology; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D006801:Humans; D006973:Hypertension / Q000453:epidemiology; D007070:Immunoglobulin A / Q000097:blood; D007074:Immunoglobulin G / Q000097:blood; D007564:Japan / Q000453:epidemiology; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000453:epidemiology / Q000209:etiology* / Q000382:microbiology; D016017:Odds Ratio; D012307:Risk Factors; D016036:Seroepidemiologic Studies; D012907:Smoking / Q000453:epidemiology
chemical_list: D000907:Antibodies, Bacterial; D007070:Immunoglobulin A; D007074:Immunoglobulin G