Predictive Value of Triglyceride-Glucose Index for All-Cause and Cardiovascular Mortality in Patients With Diabetes Mellitus: A Retrospective Study: TyG Index and Mortality in Diabetes.

Objective: To determine the associations between triglyceride-glucose (TyG) index and mortality from all causes and cardiovascular causes in diabetic population. Methods: 3349 participants with diabetes mellitus (DM) from the 1999-2014 National Health and Nutrition Examination Surveys (NHANES), aged 18-85 years were included and grouped based on the TyG index in quintiles. Mortality was followed up through December 31^th, 2015. Cox proportional hazards models were used to assess the hazard ratios (HRs) and 95% confidence intervals (CIs). We clarified the shape of association between TyG index and mortality using restricted cubic splines and piecewise linear regression. Results: After a median follow-up period of 82 months, 800 (23.9%) deaths occurred, of which 190 (5.7%) were due to cardiovascular causes. Participants in the top quintile had higher risks of all-cause mortality (HR, 1.38; 95% CI, 1.04-1.48) and cardiovascular mortality (HR, 2.43; 95% CI, 1.32-4.45) than those in the lowest quintile. TyG index and all-cause mortality had a J-shaped relationship with a threshold value of 9.32, while TyG index and cardiovascular mortality had a reversed L-shaped relationship with a threshold value of 9.37. Higher TyG index was associated with increased risks of all-cause mortality (per SD increment, HR, 1.52; 95% CI, 1.27-1.82) and cardiovascular mortality (per SD increment, HR, 2.17; 95% CI, 1.54-3.04) when above the threshold values. The sensitivity analyses demonstrated similar findings. Conclusions: TyG index in diabetic patients was nonlinearly correlated with mortality risks, potentially predicting all-cause and cardiovascular mortality.