Are morphological or functional changes in the carotid artery wall associated with Chlamydia pneumoniae, Helicobacter pylori, cytomegalovirus, or herpes simplex virus infection?

BACKGROUND AND PURPOSE: Chronic infection with Chlamydia pneumoniae, Helicobacter pylori, cytomegalovirus (CMV), and herpes simplex virus (HSV) has been implicated in the pathogenesis of atherosclerosis. The carotid intima-media thickness (IMT) can be taken to indicate early atherosclerosis, the presence of a carotid stenosis is a marker of a manifest carotid atherosclerosis, and an increase in arterial stiffness is used as marker of structural and functional changes in an atherosclerotic vessel wall.

METHODS: In 504 patients (75% men; mean age 62.9 [SD 10] years), we measured the IMT and the elastic pressure modulus (EP; n=445) of the common carotid artery and the prevalence of a internal or external carotid artery stenosis. Blood samples were taken, and antibodies against C pneumoniae, H pylori, CMV, and HSV types 1 and 2 were evaluated. Statistical evaluation was performed with regression procedures and multivariate logistic regression analyses.

RESULTS: Seropositivity for C pneumoniae was an independent predictor for a combined end point of highest category of IMT and carotid artery stenosis (OR 1.8, 95% CI 1.1 to 3.1; adjusted) for IgG titers. Independently, CMV increased the risk for the combined end point (OR 1.7, 95% CI 1.1 to 2.8; adjusted) for IgG titers and for IgA titers (OR 2.3, 95% CI 1.1 to 4. 9; adjusted). We found a significant correlation between IgG antibodies against CMV and EP; HSV type 2 IgG titers were associated with IMT and carotid stenosis, but the latter results were no longer significant after adjustment. There was no association with H pylori or HSV type 1.

CONCLUSIONS: We found a significant association of IgG antibodies against C pneumoniae and CMV with early and advanced carotid atherosclerosis. CMV was also correlated to functional changes of the carotid artery, but this could not be confirmed after adjustment.