RESUMO
BACKGROUND: The hygiene hypothesis contends that fewer opportunities for infection have led to increases in the prevalences of asthma and other allergic diseases. OBJECTIVE: This study evaluated the association between asthma, wheeze, and hay fever and antibodies to 2 oral bacteria associated with periodontal disease. METHODS: Data were obtained from the Third National Health and Nutrition Examination Survey. Serum levels of IgG antibodies to Actinobacillus actinomycetemcomitans and Porphyromonas gingivalis were quantified by enzyme-linked immunoassays in 9385 subjects age 12 years and older. The outcomes were current asthma, wheeze, and hay fever. Odds ratios (ORs) representing a 1-log-unit increase in IgG concentrations were estimated with logistic regression. ORs were adjusted for 8 confounders and weighted to represent the US population. RESULTS: For each disease outcome, geometric mean antibody concentrations were higher in persons without the disease outcome than with the disease outcome. For a 1-log-unit increase in P gingivalis antibody concentration, adjusted ORs were 0.41 (95% CI, 0.20-0.87) for asthma, 0.43 (0.23-0.78) for wheeze, and 0.45 (0.23-0.93) for hay fever. For A actinomycetemcomitans, those ORs were 0.56 (0.19-1.72), 0.39 (0.17-0.86), and 0.48 (0.23-1.03), respectively. CONCLUSION: Consistent with the hygiene hypothesis, higher concentrations of IgG antibodies to P gingivalis were significantly associated with lower prevalences of asthma, wheeze, and hay fever, and higher concentrations of IgG antibodies to A actinomycetemcomitans were significantly associated with a lower prevalence of wheeze. CLINICAL IMPLICATIONS: Colonization of the oral cavity by bacteria and other microbes might play a protective role in the etiology of allergic disease.