Cytomegalovirus infection and coronary heart disease.

To the Editor: We read with great interest the article by Ridker et al1 reporting no positive association between baseline cytomegalovirus (CMV) and herpes simplex virus serum antibodies and incidence of myocardial infarction or stroke in the Physician’s Health Study. We agree with the authors that prospective epidemiological data are scarce, and this study fills an important gap. However, we must point out that their citation of our previous study2 together with other “cross-sectional or retrospective studies” is misleading. Ridker et al state that in these previous studies, “evidence of exposure to these viruses was ascertained after rather than before the development of atherothrombosis.”1 In fact, in our study, antibodies were measured in serum that was collected 13 to 16 years before carotid atherosclerosis was measured, even though this was done “retrospectively.” Thus, the temporal …