Association of TyG index and central obesity with hypertension in middle-aged and elderly Chinese adults: a prospective cohort study

Abstract

Triglyceride glucose index (TyG) and waist circumstance have been well documented to be highly correlated with hypertension. However, the joint effect of waist circumstance and TyG on the risk of hypertension is unknown in middle-aged and elderly Chinese adults. The purpose of this study was to investigate the association between TyG and the risk of new-onset hypertension in middle-aged and elderly Chinese individuals with different waist circumstances. The multicentred prospective cohort study was conducted in 28 provinces of China including a total of 5865 eligible participants aged ≥ 45 years old. Cox regression was performed to examine the relationship of TyG index and hypertension with adjustments for the pertinent variables. Besides, the relationship was explored in different groups on the basis of waist circumstance. There was no significant correlation between TyG index and new-onset hypertension after adjustment for pertinent variables (hazards ratio [HR]: 0.99; 95% confidence interval [CI]: 0.80–1.24). When the association was explored in different waist circumstance groups, multivariate cox regression analyses revealed that TyG was an independent factor positively associated with the risk of hypertension in central obesity prophase group (HR: 1.57; 95% CI 1.13–2.16). Among individuals with central obesity, relative to population with lower TyG (Q1: 4.96–8.18), people who had higher TyG (Q3: 8.52–8.95; Q4: 8.95–12.14) were associated with significantly lower HR for hypertension. There was no conspicuous correlation between TyG index with new-onset hypertension in normal waist circumstance (HR: 1.05; 95% CI 0.84–1.30). The research demonstrated the positive relationship of TyG with risk of hypertension among individuals with central obesity prophase, negative relationship of TyG with hypertension among population with central obesity and inconspicuous correlation of TyG with hypertension among individuals with normal waist. In conclusion, the study findings supported the combined effects of TyG index and waist circumference in predicting hypertension in middle-aged and elderly Chinese individuals.