Background: It has been reported that the triglyceride-glucose (TyG) index may serve as a simple and credible surrogate marker of insulin resistance (IR). However, its association with macrovascular and microvascular damage is unclear. Accordingly, the objective of the present study is to investigate the association of macrovascular and microvascular damage with the TyG index.
Methods: A total of 2830 elderly participants from the Northern Shanghai Study (NSS) were enrolled. The TyG index was calculated as ln[fasting triglycerides (mg/dL) × fasting glucose (mg/dL)/2]. Parameters of vascular damage, including carotid-femoral pulse wave velocity (cf-PWV), brachial-ankle pulse wave velocity (ba-PWV), ankle-brachial index (ABI), carotid intima-media thickness (CMT), carotid plaque, estimated glomerular filtration rate (eGFR) and the urine albumin-to-creatinine ratio (UACR), were measured and calculated.
Results: In univariate logistic regression, an increased TyG index was associated with a higher risk of cf-PWV > 10 m/s, ba-PWV > 1800 cm/s, ABI < 0.9, microalbuminuria (MAU) and chronic kidney disease (CKD). In multivariable logistic regression, there was a significant increase in the risk of cf-PWV > 10 m/s (OR = 1.86, 95% confidence interval [95% CI] 1.37-2.53, Pfor trend < 0.001), ba-PWV > 1800 cm/s (OR = 1.39, [95% CI] 1.05-1.84, Pfor trend= 0.02), MAU (OR = 1.61, [95% CI] 1.22-2.13, Pfor trend < 0.001) and CKD (OR = 1.67, [95% CI] 1.10-1.50, Pfor trend= 0.02) after adjustment for age, sex, BMI, waist circumference, smoking habit, hypertension, family history of premature CVD, diabetes, HDL-C, LDL-C, insulin therapy and statin therapy. However, no significant relationship was observed between the TyG index and lower extremity atherosclerosis, carotid hypertrophy or carotid plaque.
Conclusion: An elevated TyG index was significantly associated with a higher risk of arterial stiffness and nephric microvascular damage. This conclusion lends support to the clinical significance of the TyG index for the assessment of vascular damage.
Keywords: Insulin resistance; Macrovascular damage; Microvascular damage; Triglyceride glucose index.