Association Between Body Mass Index and Resting Blood Pressure in a Nondiabetic Population: Mediating Effect of Triglyceride-Glucose Index

Background: The role of the triglyceride-glucose (TyG) index in determining the effect of obesity on blood pressure (BP) in patients without diabetes remains unclear. We examined the association between body mass index (BMI), the TyG index, resting BP, and hypertension in Korean adults. Methods: We used the baseline data (4206 males and 4724 females aged 40-69 years) from the Korean Genome and Epidemiology Study conducted from 2001 to 2002. The primary outcomes were the TyG index, BMI, resting BP, and hypertension. The demographic characteristics, health behaviors, levels of fasting blood glucose, insulin resistance (IR) markers, lipoprotein lipids, and liver enzymes were included as covariates. Results: The TyG index was significantly associated with higher IR marker levels, poor lipoprotein-lipid profiles, elevated hepatic liver enzyme levels, elevated BP, and hypertension. Logistic regression analysis showed that individuals living with obesity had a higher risk of hypertension compared to individuals with underweight. Individuals in the second, third, and fourth quartiles of the TyG index had a higher risk of hypertension compared with those in the first quartile (odds ratio = 1). Mediation analysis showed that BMI has an indirect effect on diastolic and systolic BP through the TyG index. Conclusion: Our study findings indicate that the TyG index plays a pathological intermediary role between obesity and increased BP in individuals without diabetes, implying its clinical value in assessing the impact of obesity on hypertension risk.