Association between triglyceride-glucose index and all cause mortality in critically ill patients with heart failure

Abstract

The triglyceride-glucose (TyG) index is regarded as a surrogate marker of systemic insulin resistance (IR). Studies have substantiated the impact of IR on cardiovascular diseases. Nonetheless, the prognostic value of the TyG index in critical patients with heart failure (HF) with intensive care unit (ICU) admission remains unclear. This study aims to assess the association between the TyG index and all-cause mortality in critically ill patients with HF. Patients with HF requiring ICU admission were identified from the Medical Information Mart for Intensive Care IV (MIMIC-IV) database and subsequently stratified into quartiles based on their TyG index. The primary outcome was 30-day all-cause mortality, and the secondary outcome was 1-year all-cause mortality. The relationship between the TyG index and all-cause mortality in HF patients was analyzed using multivariable Cox proportional hazards models and restricted cubic splines. A total of 1220 patients (62.4% men) were enrolled, with a mean age of 70.6 years. The 30-day and one-year all-cause mortality rate were 15.7% and 34.6%, respectively. Multivariable Cox regression revealed that TyG index was significantly associated with an elevated risk of 30-day all-cause mortality (adjusted HR, 1.360; 95% CI, 1.093-1.694; P = 0.006), but not with one-year mortality (adjusted HR 1.046; 95% CI 0.895-1.222, P = 0.574). Restricted cubic splines showed a progressively increasing risk of 30-day mortality was linearly related to an elevated TyG index. Subgroup analyses indicated a more prominent association between TyG index and 30-day mortality in patients with age ≤ 65, female or BMI > 30 kg/m². In critically ill patients with HF, the TyG index is significantly associated with short-term all-cause mortality. Our results highlight that the TyG index can be useful in identifying HF patients at high risk of all-cause mortality and require close follow-up after discharge.

Keywords: All-cause mortality; Heart failure; Insulin resistance; MIMIC-IV database; Triglyceride-glucose index.

Fig. 1

Flowchart illustrating selection of patients from the MIMIC-IV database.

Fig. 2

Kaplan–Meier survival analysis curve for 30-day all-cause mortality. TyG index quartiles: Q1 (7.252–8.544), Q2 (8.544–8.937), Q3 (8.937–9.376), Q4 (9.376–12.634). Kaplan–Meier survival curve shows cumulative probability of all-cause mortality according to TyG quartiles at 30 days adjusted for age, gender, BMI, race, RR, MBP, hemoglobin, creatinine, potassium, INR, LVEF, SAPSII, LODS, APSIII, SOFA.

Fig. 3

The relationship between TyG index and the risk of 30-day mortality in critical ill patients with HF by restricted cubic spline regression. Graphs show HR for 30-day mortality according to TyG index adjusted for age, gender, BMI, race, RR, MBP, hemoglobin, creatinine, potassium, INR, LVEF, SAPSII, LODS, APSIII, SOFA. Data were fitted by a Cox regression model, and the model was conducted with 4 knots at the 5th, 35th, 65th, 95th percentiles of TyG index (reference is the 5th percentile). Solid lines indicate ORs, and shadow shape indicate 95% CIs. HR hazard ratio, CI confidence interval, TyG triglyceride-glucose index.

Fig. 4

Forest plots of hazard ratios for the primary endpoint in different subgroups. HR hazard ratio, CI confidence interval, BMI body mass index, LVEF left ventricular ejection fraction.