Baseline IgG Antibody Titers to Chlamydia pneumoniae, Helicobacter pylori, Herpes Simplex Virus, and Cytomegalovirus and the Risk for Cardiovascular Disease in Women

BACKGROUND: Results of cross-sectional and retrospective studies have suggested that chronic infection may be a risk factor for cardiovascular disease. However, prospective data evaluating the relation between baseline antibody titers against various plausible agents and risk for cardiovascular disease are sparse, particularly among women. OBJECTIVE: To determine whether previous exposure to Chlamydia pneumoniae, Helicobacter pylori, herpes simplex virus, or cytomegalovirus is associated with increased risk for cardiovascular events. DESIGN: Prospective, nested, case-control study. SETTING: Women's Health Study. PARTICIPANTS: Apparently healthy postmenopausal women. MEASUREMENTS: IgG antibody titers against C. pneumoniae, H. pylori, herpes simplex virus, and cytomegalovirus were measured in baseline blood samples obtained from 122 study participants who subsequently reported a first cardiovascular event (case-patients) and 244 participants matched for age and smoking status who did not report a cardiovascular event (controls) during 3 years of follow-up. RESULTS: Little evidence was found of an association between risk for cardiovascular events and baseline IgG seropositivity for antibodies against C. pneumoniae (rate ratio, 1.1 95% CI, 0.7 to 1.8), H. pylori (rate ratio, 0.90 CI, 0.6 to 1.4), herpes simplex virus (rate ratio, 1.2 CI, 0.6 to 2.1), and cytomegalovirus (rate ratio, 0.9 CI, 0.6 to 1.5). In addition, there was little evidence of an association between a participant's total number of infections and subsequent cardiovascular risk (P > 0.2). CONCLUSION: In apparently healthy postmenopausal women, little evidence was found that previous infection, as measured by IgG antibody titers to C. pneumoniae, H. pylori, herpes simplex virus, and cytomegalovirus, is associated with subsequent risk for cardiovascular disease.