Antibody Response to Periodontal Pathogens in Myocardial Infarction and Periodontitis

OBJECTIVES: Patients diagnosed with periodontal disease are associated with a higher risk of myocardial infarction. The objective of this study was to investigate the relationship between these two diseases and the host immune response. METHODS: Data were derived from a subset of the National Health and Nutrition Examination Survey (NHANES III, 1991-94). The study population included 5002 subjects, 40 years and older and provided data on serum IgG levels to P. gingivalis (Pg) and A. actinomycetemcomitans (Aa). Periondontal disease (PD) was defined as the presence of one or more periodontal sites with both attachment loss (>3mm) and probing depth of >4mm. IgG was dichotomized as high (>168EU for Pg, >156 for Aa) and low. Myocardial infarction (MI) was categorized as yes or no based on self-reported data. Logistic regression analyses examined the association between independent variables (IgG to Aa and Pg) with dependent variables (PD and MI). RESULTS: The overall prevalence rates of PD, MI, IgG-Pg, and IgG-Aa were 55.5%, 6.2%, 14.5% and 10.8%. Subjects with high IgG-Aa and IgG-Pg had higher rates of periodontal disease (70.2% and 74.5% respectively) compared to those with low levels of the antibodies. The prevalence of myocardial infarction among the various subgroups ranged from 3.9% among those with higher levels of IgG-Aa to 7.2% among those without periodontal disease. Subjects with high IgG-Pg were two times more likely to have periodontal disease compared to those with low IgG-Pg (OR=1.9, 95% CI=1.4, 2.7). The relationships between IgG-Aa and PD or MI and between IgG-Pg and MI were not statistically significant. No associations were found between certain independent and dependent variables when PD and MI were considered separately or collectively. CONCLUSION: Although the study confirms the role of P. gingivalis in chronic periodontitis, antibody levels to periodontitis was not associated with myocardial infarction.