This study aimed to evaluate whether coffee consumption and caffeine intake are independently associated with periodontitis infection.
Coffee consumption was categorized into binary and continuous variables, serving as the exposure factor alongside caffeine intake, with periodontitis infection as the outcome variable. Other covariables were regarded as potential confounders. The cross-sectional study was conducted based on the national health and nutrition examination survey, with multivariate regression models, subgroup analyses, smooth fitting curves, and threshold effect examinations conducted to pursue a definite correlation between exposures and the outcome.
Negative associations were discovered between binary coffee consumption (OR = 0.81, 95% CI = (0.71, 0.92), p-value = 0.001) and caffeine intake (Q3: OR = 0.77, 95% CI = (0.66, 0.91), p-value = 0.002; Q4: OR = 0.76, 95% CI = (0.64, 0.90), p-value = 0.001) with periodontitis infection, respectively, with all confounders adjusted. In subgroup analyses stratified by gender, diabetes mellitus status, and hypertension status, interaction, and threshold effects were observed, which were intuitively revealed by smooth-fitting curves.
Significant negative associations between binary consumption and caffeine intake and periodontitis infection separately were indicated, with no evidence suggesting a credible correlation between continuous coffee consumption and infection risk of periodontitis. The benefits of the behavior of consuming coffee and caffeine were more obvious among males and individuals who did not suffer from diabetes or hypertension.