Insulin resistance and periodontitis: Mediation by blood pressure

Abstract

AimThis study investigated the association between the triglyceride‐glucose (TyG) index, a surrogate marker of insulin resistance, and moderate/severe periodontitis and the role of blood pressure as a mediator in this association. A second aim was to assess the role of cardiometabolic conditions such as obesity, hypertension, and dyslipidemia as potential effect modifiers.MethodsData from 5733 US adults aged 30–64 years and with complete periodontal examination were analyzed (NHANES 2011–2014). Participants were classified as having moderate/severe periodontitis or mild/no periodontitis according to the CDC/AAP criteria as the outcome. The exposure was the TyG index, while both systolic (SBP), and diastolic (DBP) blood pressure were tested as mediators using parametric g‐formula. Analyses were adjusted for relevant confounders, namely, age, sex, ethnicity, poverty‐income ratio, and smoking, using inverse probability treatment weighting. Obesity status (based on a body mass index ≥30 kg/m2), self‐report of hypertension and dyslipidemia (calculated based on the thresholds provided by National Cholesterol Education Program‐Adult Treatment Panel‐III) were tested as effect modifiers.ResultsThe findings showed the TyG index to be associated with increased odds of moderate/severe periodontitis [odds ratio (OR), 95% confidence interval (CI) = 1.17 (1.11–1.23)], with 50% of the total effect mediated by SBP. Stratified analysis showed a stronger association in individuals with obesity, hypertension, and dyslipidemia compared to those without these conditions. However, in those taking anti‐hypertensive medications, the association was partially mitigated. Sensitivity analysis using imputed data showed consistent results.ConclusionThe TyG index was associated with increased odds of moderate/severe periodontitis, especially in individuals with obesity, hypertension, and dyslipidemia. SBP levels partially mediated this association.