Association between self‐reported oral symptoms and irritable bowel syndrome: A prospective cohort study based on UK Biobank

BACKGROUND: Although periodontal disease (PD) has been linked to an increased risk of several gastrointestinal diseases such as inflammatory bowel disease and celiac disease, research on the association between PD and irritable bowel syndrome (IBS) is still insufficiently explored, with conflicting results. We aimed to investigate the potential association between self-reported oral symptoms and IBS based on the UK Biobank cohort. METHODS: Oral symptoms were assessed via questionnaire. Participants reporting at least one of gum pain, gum bleeding, or loose teeth were classified as being at high risk of PD. The primary outcome was incident IBS. Cox proportional hazards regression, incorporating multiple covariates, was applied to calculate hazard ratios (HRs) and 95% confidence intervals (CIs) in examining the links between oral symptoms, high PD risk, and IBS incidence. Subgroup and sensitivity analyses were conducted. RESULTS: This longitudinal cohort study was conducted among 420,371 participants, 8642 incident cases of IBS (2.1%) were identified. Cox regression analyses showed that several oral symptoms, including mouth ulcers, gum pain, gum bleeding, toothache, and denture use, were significantly associated with an increased risk of IBS. No significant association was observed between loose teeth and IBS in any model. Compared with the low PD risk group, individuals at high risk of PD had an elevated likelihood of IBS onset (HR = 1.19, 95% CI: 1.13-1.25). Subgroup and sensitivity analyses strengthened the validity of these findings. CONCLUSION: Oral symptoms (mouth ulcers, gum pain, gum bleeding, toothache, and denture use) and high risk of PD were both associated with an increased incidence of IBS. Incorporating oral health management into comprehensive strategies may contribute to the prevention of IBS. PLAIN LANGUAGE SUMMARY: There is a close connection between oral health and gut health. This long-term study of more than 420,000 UK adults found that individuals experiencing mouth ulcers, gum pain, gum bleeding, toothache, or denture use had a higher risk of developing irritable bowel syndrome (IBS) later in life. Additionally, participants classified as being at high risk for periodontal disease (PD; those with at least one symptom of gum pain, gum bleeding, or loose teeth) had about a 19% higher risk of developing IBS compared with the low PD risk group. Therefore, incorporating active management of oral problems into personal health practices could offer a new perspective for IBS prevention. Caring for oral health is not just about maintaining local wellness but is a crucial part of overall bodily health.