Effect of oral health on chronic intestinal diseases and all-cause mortality in US adults: results from the NHANES 2005-2008 database

Background: Oral health and gut health are closely related. Gut flora changes can be modulated via the mouth-gut axis, impacting bowel health. This study aimed to explore the relationship between oral health and the incidence of chronic diarrhea and constipation, as well as its impact on all-cause mortality. Methods: This cross-sectional study used data from the 2005–2008 National Health and Nutrition Examination Survey (NHANES) database. Multivariable logistic regression and subgroup analyses assessed the associations between oral health status, dental pain frequency, and chronic diarrhea/constipation. Multivariable Cox regression evaluated the link between oral health and all-cause mortality in patients with chronic constipation or diarrhea. Results: Chronic constipation was present in 10.37% (957/9231) of participants, and chronic diarrhea in 12.06% (1113/9231). Adjusted multivariable logistic regression models showed that poor oral health and high frequency of dental pain were significantly associated with an increased risk of chronic constipation [odds ratio (OR) = 1.65, 95% confidence interval (CI) 1.28–2.12, P  < 0.001; OR = 1.43, 95% CI 1.01–2.02, P  = 0.044] and chronic diarrhea (OR = 1.31, 95% CI 1.07–1.71, P  = 0.044; OR = 1.69, 95% CI 1.35–2.11, P  < 0.001), particularly in smokers, drinkers, and those with a history of neoplasia. Adjusted multivariable Cox regression indicated that poor dental health was linked to all-cause mortality in diarrhea patients (HR = 1.66, 95% CI 1.08–2.54, P = 0.033). Conclusion: Oral health conditions are significantly correlated with chronic intestinal diseases. This discovery highlights the significance of oral factors in the treatment strategies for chronic intestinal diseases.