Association between the triglyceride glucose index and cardiovascular mortality in obese population

Abstract

Background and aim: The triglyceride and glucose (TyG) index, as a surrogate marker of insulin resistance, was related to increased mortality. Our study aimed to investigate the specific relationship between the TyG index and all-cause mortality among obese population.

Methods and results: 6731 participants with obesity were enrolled from the National Health and Nutrition Examination Survey (NHANES). The TyG index was calculated as log [fasting triglycerides (mg/dL) x fasting glucose (mg/dL)/2]. The baseline levels of TyG associated with the risk of all-cause and cardiovascular mortality were evaluated by Cox proportional hazards models. After a follow-up of 16.7 years, 693 all-cause death and 133 cardiovascular deaths occurred. Dose-response curve showed that the association of the risk of all-cause mortality was non-linear (p = 0.019) and the corresponding TyG index ranged 8.78 to 9.64 for the lowest risk. Compared with the reference quartile of 8.79-9.22, the multivariate-adjusted hazards ratios were 1.32 ((95% confidence interval 1.03-1.70; p = 0.030) in the lowest quartile for all-cause mortality, and 0.55 (0.32-0.93; p = 0.025) in the second quartile for cardiovascular mortality.

Conclusions: TyG index was associated with the risk of all-cause mortality in obese participants and the level associated with the lowest risk was 8.78-9.64.

Keywords: All-cause mortality; Cardiovascular mortality; Insulin resistance; Obesity; Triglyceride glucose index.