Association between allergic rhinitis and oral disease: a meta-analysis

Introduction: The bidirectional relationship between allergic rhinitis (AR) and oral disease remains controversial. Therefore, this study aimed to amalgamate the current body of scientific literature to summarize and elucidate the association between AR and oral disease. Methods: A comprehensive search of PubMed, Embase, Cochrane Library, and Web of Science identified observational studies exploring AR and oral diseases. The study results, complete with their respective 95% confidence intervals (CIs), were aggregated by employing a random-effects model for data synthesis. Supplementary subgroup and sensitivity analyses were conducted to evaluate the stability and reliability of the study outcomes. Results: Nine studies were included. When examining oral health status as the exposure, the pooled results showed no significant associated with the odds of AR (OR=1.01, 95%CI:0.84-1.22, p=0.884; I²=95%). Similarly, when evaluating AR as the exposure, no overall association was observed between AR and the odds of oral diseases (OR=0.97, 95%CI:0.76-1.23, p=0.798; I²=100%). However, in subgroup analyses limited to cross-sectional studies examining the association between AR and oral diseases, a reduced odds was observed (OR=0.77, 95%CI:0.67-0.89, p<0.001; I²=0%), suggesting a possible inverse correlation in these specific study designs. Conclusion: This meta-analysis found no significant overall association between oral health and allergic rhinitis in either direction of exposure. Considerable heterogeneity was present among studies, particularly in analyses of AR as an exposure. Subgroup findings from cross-sectional studies suggest a potential inverse relationship between allergic rhinitis and oral diseases; however, these results should be interpreted cautiously due to study design limitations and require validation in future prospective studies.