Triglyceride glucose index, a novel marker of insulin resistance, predicts outcomes in patients with heart failure with preserved ejection fraction

Abstract Background Insulin resistance (IR) is a characteristic feature of heart failure (HF), and it is present both in diabetic- and non-diabetic patients with HF. It is observed in patients with HF with preserved ejection fraction (HFpEF) as well as in those with HF with reduced ejection fraction (HFrEF). It is still not fully understood how IR can affect the clinical outcome in patients with HFpEF. Triglyceride glucose index (TyG index) is a novel, simple marker of IR which is well correlated with HOMA-IR. Purpose To investigate the correlation between TyG index and clinical outcome in patients with hospitalized HFpEF. Methods We enrolled 1231 patients registered in the PURSUIT-HFpEF (Prospective, Multicenter, Observational Study of Patients with Heart Failure with Preserved Ejection Fraction) study, which is a multicenter registration of patients hospitalized for acute decompensated HFpEF, for the present study. TyG index was calculated as Ln(serum triglyceride [mg/dL] x fasting blood glucose [mg/dL]/2) using blood sample before discharge. We followed the study patients for median of 387 days (IQR 239-727 days) to observe all-cause death and the major adverse cardiovascular events (MACE; composite of death, heart failure hospitalization and stroke). Results We could calculate TyG index in 917 patients (81±9 year old, 55.3% female) with the mean value of 8.5±1.5. Diabetes was observed in 360 (39.3%) patients, and they had higher TyG index than non-diabetic patients (8.8±0.6 vs. 8.4±.05, p<0.0001). Cox proportional hazard model selected TyG index score as an independent predictor for all-cause death regardless of history of diabetes, hypertension and dyslipidemia (p=0.004). We divided patients into 4 groups based on TyG index. Kaplan-Meier curves indicated the difference in all-cause mortality among 4 groups (Figure Left, p=0.0003 by log-rank test). Incidence of MACE was also significantly different among 4 groups (Figure Right, p=0.007 by log-rank test). Conclusion TyG index predicted all-cause mortality and MACE in patients with HFpEF regardless of diabetic state.Kaplan-Meier curves for death and MACE