Chlamydia pneumoniae (Cp) infection, is that a risk factor of atherosclerosis? - On the basis of seroepidemiologic study -

Background : Several risk factors of atheroscleros is have been known. However, many patients have been experienced coronary heart disease without known risk factors of atherosclerosis, and it has been suggested that some kinds of infections may be associated with atheroscleros is as risk factors. Among many candidate infectious agents, Chlamydia pneumoniae (Cp) has been showing apositive relationship with therosclerosis. Therefore, we investigated mas sive serologic study using a ELISA for detection of Cp to identify the relationship with atherosclerosis as a risk factor. Methods : Serologic tes ts were done in patients who were performed coronary angiogram among patients with typical symptoms of angina and with pos itive results in non- invasive test (EKG, T readmill) from May 1997 to September 1998. Among them, patients with luminal narrowing of more than 50% in at leas t one vessel were grouped into ' Case group (Group I)' and patients with normal coronary arteries or minimal lesion were grouped into ' Positive control group(Group II)' . We also studied healthy persons , as a ' Negative control group (Group III), who had not experienced any symptoms related with coronary heart disease and had normal EKG findings . Serologic tests for Cp- IgG and Cp- IgA were performed by ELISA. Results : There was no statistical difference in seropositive rate between Group I and II, but seropos itive rate of Group III was s tatistically lower than those of Group I or II for Cp- IgG, Cp- IgA, and both, respectively. But multivariate analysis by us ing logis tic regres sion showed no s tatistcal differences between groups. Subgrouping by several traditional risk factors, seropos itive rate for Cp- IgG and both IgG and IgA, was significantly different between Group I and III in patients without traditional risk factors of atheroscleros is , such as , females, non- smokers, normotension, non- diabetes normal cholesterol level, and high HDL- choles terol level. For Cp- IgA, however, the difference was observed in normotension, non- diabetes , and in normal cholesterol level. In multivariate analys is , seropositive rate for Cp- IgG and both IgG and IgA was significantly different between Group I and III in females and non- smokers , but not for the Cp- IgA Conclusions : These results suggest that Cp infection might be an independent risk factor of atherosclerotic coronary disease, particularly in patients without traditional risk factors of atherosclerosis. Further study with coronary tissue should be continued.(Korean J Med 58:411- 419, 2000)ope