Chlamydophila (Chlamydia) pneumoniae but not Helicobacter pylori infection, is associated with cerebral infarction in Japanese community-dwelling populations: The Jichi Medical School Cohort Study

ABSTRACT

Background: Chronic infections, such as Helicobacter pylori (H. pylori) and Chlamydophila pneumoniae (C. pneumoniae), are known to contribute to atherosclerosis. However, the relationship of the infections to cerebral infarction is still controversial. Methods: The Jichi Medical School (JMS) Cohort Study, a prospective population-based study, investigated the risk factors of cardiovascular disease in Japanese community-dwelling populations. In 1999, we measured serum H. pylori IgG, C. pneumoniae IgG and IgA levels in 2,632 subjects. Logistic regressions were used to analyze associations between H. pylori and C. pneumoniae seropositivities and cerebral infarction. Results: A total of 2,243 subjects were followed up and, during 10.7-years, 64 developed cerebral infarctions, whose prevalence of H. pylori IgG, C. pneumoniae IgG and IgA seropositivities were 51.6%, 71.9%, and 67.2%, respectively. Among seropositive subjects, adjusted odds ratios (ORs) for cerebral infarctions were 1.04 (95% confi dence interval (CI), 0.58-1.87, P=0.89), 2.02 (1.03-3.95, P=0.04), and 1.35 (0.73-2.49, P=0.34) respectively, after adjusting for sex, age, body mass index, total cholesterol, high-density lipoprotein cholesterol, fasting blood sugar, smoking, alcohol, and fi brinogen. C. pneumoniae IgG seropositivities in subjects aged > 65 years were associated with cerebral infarctions, whereas those in subjects aged < 65 years, were not. Conclusions: C. pneumoniae IgG was associated with cerebral infarction, C. pneumoniae IgA and H. pylori IgG were not.