Comparative analysis of antibodies to four major periodontal bacteria in respiratory diseases: a cohort study.

OBJECTIVES:To make a descriptive comparison of antibodies to four major periodontal bacteria and their relation to the respiratory diseases asthma and bronchitis/emphysema, and to cancer incidence. METHODS:The serum of a random sample of men with no history of cancer incidence (n=621) was analysed by the ELISA method for antibody levels of four periodontal bacteria; the anaerobes of the so-called red complex Tannerella forsythia (TF), Porphyromonas gingivalis (PG), and Treponema denticola (TD), and the facultative anaerobe Aggregatibacter actinomycetemcomitans (AA). The antibody readings were divided into quartiles and the distribution of cases of the relevant diseases as compared with the non-cases. Comparisons of the quartile distributions were by the Pearson χ2 test. Data and serum from the Oslo II study of Norwegian men from 2000 were used. The ELISA analyses were performed on thawed frozen serum. Cancer data from 17.5 years of follow-up were provided by the Norwegian Cancer Registry. RESULTS:In all, 52 men had reported asthma and 23 men had bronchitis/emphysema at the health screening. Results on cancer incidence are given for all respiratory cancers, n=23, and bronchi and lung cancers separately, n=18. Stratified analyses were performed for the four endpoints showing significant association with low levels of TD antibodies for bronchitis; p=0.035. Both TF and TD were significant for low levels of antibodies among daily smokers; p=0.030 for TF and p<0.001 for TD in the analysis of the full study sample. For PG and AA, no such associations were observed. An association with respiratory cancers was not observed. CONCLUSION:A low level of TD was associated with bronchitis/emphysema compared with the rest of the cohort. In the total study sample, low levels of antibodies to both TF and TD were associated with daily smoking.