Serum antibodies to periodontal pathogens are related to allergic symptoms

The association between periodontitis and allergic symptoms has been investigated. However, the difference in immune signatures between them remains poorly understood. This cross-sectional study assessed the relationship between serum immunoglobulin G (IgG) antibodies to periodontal pathogens and allergic symptoms in a nationwide population cohort.

Two phases of the Third National Health and Nutrition Examination Survey (NHANES III) were used as discovery dataset (n = 3700) and validation dataset (n = 4453), respectively. Based on the antibodies against 19 periodontal pathogens, we performed an unsupervised hierarchical clustering to categorize the population into three clusters. In the discovery dataset, cluster 1 (n = 2847) had the highest level of IgG antibodies, followed by clusters 2 (n = 588) and 3 (n = 265). Data on allergic symptoms (asthma, hay fever, and wheezing) were obtained using a self-reported questionnaire. Survey-weighted multivariable logistic regression evaluated the association between these clusters and allergic symptoms.

In the discovery dataset, the participants with lower levels of antibodies to periodontal pathogens exhibited a higher risk of asthma (odds ratio [OR]_{cluster 3 vs. cluster 1} = 1.820, 95% confidence interval [CI]: 1.153-2.873) and wheezing (OR_{cluster 3 vs. cluster 1} = 1.550, 95% CI: 1.095-2.194) compared to those with higher periodontal antibodies, but the non-significant association with hay fever. Consistent results were found in the validation dataset.

Serum IgG titers to periodontal pathogens were inversely associated with the risk of asthma and wheezing, suggesting the potentially protective role against allergic conditions.