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The following is a summary of “Association of albumin-corrected anion gap and acute kidney injury in heart failure patients: a competing risk model analysis,” published in the April 2025 issue of BMC Cardiovascular Disorders by Ruan et al. 

The coexistence of heart failure (HF) and acute kidney injury (AKI) significantly exacerbates patient mortality, highlighting the need for reliable markers to identify patients with HF at elevated risk for AKI. Although albumin-corrected anion gap (ACAG) has recently emerged as a potential clinical indicator, its association with AKI risk in patients with HF remains unexplored. This study aimed to evaluate the predictive value of ACAG for AKI in individuals with heart failure.

Data were obtained from the Medical Information Mart for Intensive Care IV (MIMIC-IV) database, including 5,972 patients diagnosed with HF. The predictive performance of ACAG for AKI risk was assessed through receiver operating characteristic (ROC) curve analysis and decision curve analysis. Logistic regression models and restricted cubic spline (RCS) analysis were employed to examine the relationship between ACAG and the occurrence of AKI. Additionally, a competing risk model was constructed to further validate the findings, considering in-hospital mortality as a competing event.

Among the analyzed cohort, 49.82% (2,886/5,972) developed AKI during hospitalization. ACAG demonstrated moderate predictive performance for AKI, with an area under the ROC curve (AUC) of 0.656. In multivariate logistic regression analyses, continuous increases in ACAG were consistently associated with higher odds of developing AKI after adjusting for confounders (Model 1: OR = 1.094, 95% CI: 1.078–1.110; Model 2: OR = 1.150, 95% CI: 1.133–1.166; Model 3: OR = 1.035, 95% CI: 1.017–1.054). Furthermore, patients categorized into high ACAG groups exhibited significantly greater risks of AKI across all models (all P < 0.001). Elevated ACAG was also independently linked to an increase in in-hospital mortality (P < 0.001). In the competing risk analysis, even after accounting for death as a competing event, high ACAG remained a significant risk factor for AKI (P < 0.001).

In conclusion, elevated ACAG levels are associated with a heightened risk of AKI among patients with heart failure. These findings suggest that ACAG could serve as a valuable marker for early risk stratification, enabling clinicians to identify patients with HF who may benefit from closer monitoring and proactive renal protection strategies.

Source: bmccardiovascdisord.biomedcentral.com/articles/10.1186/s12872-025-04723-7