Abstract
BACKGROUND: Acute kidney injury (AKI) is a common and life-threatening complication among critically ill patients with cirrhosis, yet early prediction remains challenging. The C-reactive protein-triglyceride-glucose index (CTI), a marker reflecting systemic inflammation and insulin resistance, may serve as a useful prognostic tool. However, its association with AKI in this population has not been previously investigated. METHODS: A cohort of patients was selected from the Medical Information Mart for Intensive Care IV (MIMIC-IV) database. The primary outcome was the incidence of AKI during intensive care unit (ICU) stay. Secondary endpoints included the ICU length of stay and the hospital length of stay. Least Absolute Shrinkage and Selection Operator (LASSO) regression was used to identify key predictors of AKI. Logistic regression models were then applied to assess the association between CTI and the risk of AKI, treating CTI both as a continuous and categorical variable. A restricted cubic spline model was established to evaluate the dose–response relationship. Finally, subgroup analyses were performed across strata defined by the results of multivariate logistic regression analysis. RESULTS: A total of 887 ICU patients with cirrhosis were included. AKI exhibited an incidence of 67.5% and exhibited a positive association with increasing CTI quartiles (from 59.5% in Q1 to 73.3% in Q4; P = 0.009). Higher CTI levels were associated with more severe AKI stages (P = 0.015), greater renal replacement therapy (RRT) use (1.8% to 7.7%; P = 0.016), and longer ICU and hospital stays (P = 0.028 and P = 0.002, respectively). Multivariate logistic regression confirmed CTI as an independent predictor of AKI (OR = 1.26, 95% CI: 1.03–1.55; P = 0.027). A linear relationship between CTI and AKI was observed using restricted cubic spline models. Subgroup analyses showed consistent associations between AKI and CTI across different clinical strata. CONCLUSION: CTI is independently associated with AKI risk, severity, and adverse outcomes in critically ill patients with cirrhosis. As a readily available marker with physiological relevance, CTI may aid in early risk stratification for AKI and guide preventive strategies in intensive care settings. CLINICAL TRIAL NUMBER: Not applicable. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1186/s12882-025-04613-2.