Correlation between Helicobacter pylori Infection and Autoimmune Thyroid Disease.

Background/Aims Helicobacter pylori infection may be associated with extra-digestive diseases such as coronary artery disease, nonalcoholic fatty liver disease and autoimmune disease. Many studies used serological tests to diagnose of H. pylori infection, but these methods detected past and current infection. The aim of this study was to determine the correlation between current infection of H. pylori and autoimmune thyroid disease. Methods A retrospective, cross-sectional study was conducted with those who received screening esophagogastroduodenoscopy between January 1, 2010 and December 31, 2018. The subjects were categorized into two groups that were H. pylori infected group and no H. pylori infected group. Anti-thyroid peroxidase (anti-TPO) antibody was compared as the primary outcome between two groups. Also, thyroid-stimulating hormone, free thyroxine, rheumatoid factor (RF) levels and thyroid function were compared. Results A total of 43,321 subjects were included in the analysis. The number of H. pylori positive subjects was 15,927 and H. pylori negative was 27,394. Anti-TPO antibodies positive rate of H. pylori positive group was 8.27% (n=1,317) and H. pylori negative group was 9.47% (n=2,595) in the univariate analysis (p<0.0001). In the multivariate analysis, the positive rate of anti-TPO antibody in the H. pylori positive group was significantly lower (odds ratio, 0.877; 95% confidence limits, 0.818 to 0.941; Pr >chi-square 0.0002) than in the H. pylori negative group and RF positive rate in the H. pylori positive group was significantly lower (odds ratio, 0.898; 95% confidence limits, 0.74 to 0.86; Pr >chi-square <0.0001) than in the H. pylori negative group when age, sex and body mass index were adjusted as covariates. Conclusions Current H. pylori infection had a statistically significant effect on the positive rate of anti-TPO antibody and RF inversely. [ABSTRACT FROM AUTHOR]