ROLE OF INFECTION AS A RISK FACTOR FOR ATHEROSCLEROSIS, MYOCARDIAL-INFARCTION, AND STROKE

An increasing body of evidence has linked infections to atherosclerosi s and thrombosis. Herpesviruses cause atherosclerosis in experimental animals. Herpesviruses can also be detected in atherosclerotic lesions in humans, Cytomegalovirus may play a role in arteriosclerosis in tra nsplanted hearts, and this virus, together with tumor suppressor prote in p53, can be found in restenosis lesions following angioplasty. Chla mydia pneumoniae and dental infections are associated with coronary he art disease in cross-sectional and longitudinal studies, and preceding respiratory infections are associated with ischemic stroke. Infection s may favor formation of atherosclerosis and thrombosis by elevation o f blood levels of fibrinogen, leukocytes, clotting factor, and cytokin es and by alteration of the metabolism and functions of endothelial ce lls and monocyte macrophages. Low-grade infections may also be one of the causes of the inflammatory reaction observed in atherosclerotic le sions and acute ischemic symptoms, reflected in elevated levels of C-r eactive protein, These observations warrant further studies in this fi eld.