Triglyceride-glucose index association with kidney function in adults; a population-based study

Hyperglycemia and hypertriglyceridemia, two key elements of insulin resistance, are linked with developing kidney dysfunction. The Triglyceride-glucose (TyG) index, composed of blood lipids and glucose, may help assess the risk of kidney dysfunction. This study aimed to clarify the effect of TyG on estimated glomerular filtration rate (eGFR) reduction in adults in western Iran.

This cross-sectional study involved a total of 9,661 participants, aged 35 to 65 years, drawn from the Ravansar Non-Communicable Diseases (RaNCD) cohort. Among these, 1,044 individuals were identified with chronic kidney disease (CKD), while 8,617 were classified as healthy. The triglyceride-glucose index (TyG) was calculated using the formula ln [triglyceride (mg/dL) × fasting plasma glucose (mg/dL)/2]. Additionally, an eGFR less than of 60 ml/min per 1.73 m² was employed to indicate kidney dysfunction.

48% of participants were male, and 40.14% were from rural areas. The prevalence of reduced eGFR was 10.81%. Compared to the first quartile, the fourth had significantly higher rates of hypertension, type 2 diabetes, cardiovascular disease, and dyslipidemia (P < 0.001). The odds of kidney dysfunction (eGFR reduction) were 47% in the third quartile (OR: 1.47; 95% CI: 1.20, 1.81) and 75% in the fourth quartile (OR: 1.75; 95% CI: 1.42, 2.17), significantly higher than those in the first quartile of the TyG index (P trend < 0.001), after adjustment for confounding factors.

Lipid and glucose imbalances may be markers for decreased kidney function, and it is recommended that patients with such imbalances be screened for kidney disease.