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

Oral microbiome dysbiosis may contribute to autoimmune disease development, but epidemiological evidence linking oral health and autoimmune disease risk is limited. 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. 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. 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. 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. Any self-reported oral health issues were associated with higher autoimmune disease risk. A dose-response pattern was observed with increasing number of oral health issues. Seven autoimmune diseases showed significant associations, including pernicious anemia.