Association between self-reported oral health issues and autoimmune diseases: evidence from UK biobank.

BACKGROUND: Oral microbiome dysbiosis may contribute to autoimmune disease development, but epidemiological evidence linking oral health and autoimmune disease risk is limited. OBJECTIVES: To evaluate the association between self-reported oral health issues by questionnaire-defined as the presence of painful or bleeding gums, mouth ulcers, toothache, dentures, or loose teeth-and the risk of incident autoimmune diseases in the UK Biobank cohort. MATERIALS AND METHODS: Individuals reporting any oral health issues (painful/bleeding gums, mouth ulcers, toothache, dentures, and loose teeth) were classified as any self-reported oral health issues; others as no self-reported oral health issues. We estimated hazard ratios (HRs) and 95% confidence intervals (CIs) for any autoimmune diseases and 39 types of autoimmune diseases using Cox regression models with Bonferroni correction. We investigated associations of the type and number of self-reported oral health issues with autoimmune diseases. RESULTS: Among 451,404 participants (mean age: 56.4 years, 54.2% female), any self-reported oral health issues (N = 177,198; 39.3%) were associated with an increased risk of any autoimmune diseases (HR 1.11, 95% CI 1.09-1.14). Painful gums showed the strongest association (HR 1.39, 95% CI 1.31-1.47), followed by mouth ulcers (1.23, 1.18-1.27) and toothache (1.21, 1.15-1.27). Risk increased with the number of self-reported oral health issues (per 1-issue increase: HR 1.09, 95% CI 1.08-1.11, P-trend < 0.001). For specific autoimmune disease, primary biliary cholangitis (HR 1.65, 95% CI 1.24-2.19), rheumatism (1.48, 1.23-1.77), lichen planus (1.35, 1.15-1.57), Sjögren's disease (1.30, 1.11-1.52), pernicious anemia (1.28, 1.12-1.46), rheumatoid arthritis (1.18, 1.12-1.26), and psoriasis (1.16, 1.07-1.26) were identified. CONCLUSIONS: Self-reported oral health issues were associated with an increased risk of incident autoimmune diseases, suggesting that oral health indicators may serve as clinically relevant markers of autoimmune disease risk.