Association between the indicators of insulin resistance and periodontitis: a study using data from the National Health and Nutrition Examination Survey 2009-2014.

BACKGROUND: The rising obesity rates are accompanied by an increasing prevalence of insulin resistance (IR) associated with obesity. To ascertain the best index for replacing IR, this study aimed to investigate the possible association between IR, which was assessed using the Homeostatic Model Assessment of Insulin Resistance (HOMA-IR), and the triglyceride-glucose (TyG) index and its derived indexes and periodontitis. METHODS: The association between the indicators of IR and periodontitis was assessed via multivariate-adjusted logistic regression analyses using data from the National Health and Nutrition Examination Survey (NHANES) 2009-2014. In addition, subgroup analyses and receiver operating characteristic curve analyses were conducted to explore possible influencing factors. RESULTS: Our study encompassed 1,588 participants, and 41.0% were diagnosed with periodontitis. Based on the multivariate logistic regression analysis, a higher TyG-waist-to-height ratio (WHtR) (odds ratio [OR] = 1.14, 95% confidence interval [CI]: 1.02-1.27, P = 0.0244) and HOMA-IR score (OR = 1.00, 95% CI: 1.00-1.00, P = 0.0028) were associated with an increased risk of periodontitis. Conversely, the TyG index, TyG-adjusted for body mass index, and TyG-adjusted for waist circumference (WC) were not associated with periodontitis. According to further subgroup analyses and interaction result analyses, sex affected the association between the TyG index, TyG-WC, and TyG-WHtR and periodontitis (P < 0.05 for interaction). Moreover, the influence of age regulated the association between periodontitis and both TyG and HOMA-IR score. In terms of diagnostic accuracy, the area under the receiver operating characteristic curve analysis revealed that HOMA-IR score and TyG-WHtR slightly outperformed the TyG index, TyG-body mass index, and TyG-WC. Thus, they can be robust markers for assessing IR-related periodontitis risk. CONCLUSION: A consistent and positive association was found between HOMA-IR score and TyG-WHtR and the odds of periodontitis prevalence. Hence, HOMA-IR score and TyG-WHtR were significantly associated with periodontitis in this cross-sectional study. However, prospective studies are needed to determine whether higher TyG-waist-to-height ratio and HOMA-IR score can predict the occurrence of periodontitis.