Triglyceride-glucose index and prognosis in individuals afflicted with heart failure and chronic kidney disease

Abstract

Background: The triglyceride-glucose (TyG) index has demonstrated correlations with adverse clinical outcomes in patients with ischaemic stroke, coronary heart disease and cardiac failure. However, its association with overall mortality in individuals concurrently experiencing heart failure (HF) and chronic kidney disease (CKD) remains inadequately explored.

Methods: Utilizing the Medical Information Mart for Intensive Care IV (Version 2.2) repository, subjects underwent quartile stratification based on the TyG index. The primary endpoint was all-cause mortality during hospitalization. Cox proportional hazard models were employed to examine the correlation between TyG and all-cause mortality in HF patients with CKD. Evaluation involved Kaplan-Meier (KM) analysis and restricted cubic splines (RCSs) to compare mortality rates during hospitalization and 1 year after admission across cohorts with varying TyG index levels.

Results: A cohort of 1537 HF and CKD patients participated. Cox regression analysis revealed elevated TyG levels as an independent risk factor for both in-hospital and 1 year mortality. RCS analysis indicated a rising, non-linear association between TyG levels and all-cause mortality (P value for non-linear <0.001). KM survival curves demonstrated a statistically significant reduction in survival rates within the high TyG index group compared with the low one (log-rank P < 0.001).

Conclusions: The TyG index exhibited substantial independent prognostic value for elevated in-hospital and 1 year all-cause mortality among the cohort with HF and CKD. These findings suggest that assessing the TyG index could play a crucial role in developing novel therapeutic strategies to improve outcomes for this high-risk demographic.

Keywords: MIMIC‐IV database; chronic kidney disease (CKD); heart failure (HF); hospital and 1 year mortality; prognostic indicator; triglyceride–glucose (TyG) index.

FIGURE 1

Selection flowchart for patient analysis: The Medical Information Mart for Intensive Care IV (MIMIC‐IV) (Version 2.2) database encompasses extensive medical data for 299 712 patients, which includes 431 243 hospital admissions and 73 181 ICU admissions. Of these, 10 780 hospitalized patients were diagnosed with both HF and CKD. Within this cohort, patients who met the exclusion criteria were removed from consideration (n = 9243). Ultimately, the study encompassed 1537 patients, out of whom 328 succumbed during the observation period.

FIGURE 2

Restricted cubic spline regression showed the relationship between triglyceride–glucose (TyG) index and hospitalization (Left)and 1 year follow‐up (Right) mortality. Adjusted hazard ratio (HR) is represented by solid blue lines, and 95% confidence interval (CI) is represented by blue dashed lines. The results showed that there was a non‐linear correlation between TyG index and hospitalization and 1 year mortality. The cutoff value in the risk map of hospital mortality was 9.325, while the cutoff value of 1 year mortality was 9.669.

FIGURE 3

The results of the Kaplan–Meier analysis showed the cumulative in‐hospital and 1 year mortality of HF patients with chronic kidney disease in different triglyceride–glucose (TyG) index groups. TyG index: Q1 (7.75–8.71), Q2 (8.71–9.13), Q3 (9.13–9.57) and Q4 (9.57–10.70). The survival curve of patients with a high TyG index was lower than that of patients with a low TyG index (in‐hospital log‐rank test: P < 0.001; 1 year log‐rank: P = 0.066).

FIGURE 4

The forest plot presents the hazard ratios (HRs) for in‐hospital mortality across various subgroups, complemented by an interaction analysis evaluating the relationship between the triglyceride–glucose index and in‐hospital mortality within these distinct subgroups. AF, atrial fibrillation; AMI, acute myocardial infarction; BMI, body mass index; CABG, coronary artery bypass grafting; CI, confidence interval; COPD, chronic obstructive pulmonary disease; CRRT, continuous renal replacement therapy; HBP, high blood pressure; PCI, percutaneous coronary intervention; RF, respiratory failure.