Atherosclerosis and infection due to Chlamydia pneumoniae or cytomegalovirus: weighing the evidence.

A link between infectious agents and atherosclerosis has been postulated for decades. This review describes the epidemiological and biological evidence linking cytomegalovirus and Chlamydia pneumoniae to atherosclerotic disease. Case-control studies and histologic evidence from atheromatous specimens support an association between atherosclerosis and infection with these two microorganisms, and small interventional trials appear to confirm the link with C. pneumoniae, but these findings require confirmation in larger studies. A lack of clinically relevant animal models has hampered investigations regarding biological mechanisms, particularly for C. pneumoniae.