GLUCOSE-to-potassium ratio (GPR) predicts early acute kidney injury (AKI) risk in patients with traumatic brain injury, with a significant non-linear J-shaped association identified in a large retrospective cohort.
Study Overview and Population Findings
This retrospective cohort analysis included 2,388 patients with traumatic brain injury drawn from the MIMIC-IV database, with 56.7% (1,355/2,388) developing AKI.
After adjustment for confounders, a linear association between GPR and AKI was not statistically significant (p=0.20), suggesting a more complex relationship.
Multivariable logistic regression models were used to adjust for key demographic and clinical covariates, ensuring robustness of the observed associations between GPR and AKI. Variables included admission characteristics and physiological parameters available within the MIMIC-IV dataset.
GPR Ratio and Non-Linear AKI Risk
Restricted cubic spline modelling demonstrated a significant non-linear J-shaped association between GPR and AKI risk (p for non-linearity=0.012). The GPR showed a marked increase in AKI risk once values exceeded an inflection point of approximately 30, indicating a threshold effect. This pattern suggests that elevated GPR may reflect metabolic stress and early physiological decompensation following traumatic brain injury.
Restricted cubic spline analysis provided visual confirmation of the non-linear association, reinforcing that risk elevation was not uniform across the GPR distribution but concentrated at higher levels.
Predictive Modelling and Clinical Implications
Predictive modelling using a random forest algorithm incorporating multiple clinical variables achieved superior performance in predicting AKI compared with traditional logistic regression (AUC: 0.808 vs 0.785; DeLong test p=0.025).
These findings indicate that GPR above 30 may serve as an early warning marker rather than a direct causal driver of injury, supporting its role in risk stratification after traumatic brain injury.
Clinicians may consider closer monitoring of patients with elevated GPR on admission to support earlier recognition and management of AKI. Further validation in external cohorts is warranted in future studies.
Reference
Wang H et al. Glucose-to-potassium ratio has a non-linear J-shaped association with acute kidney injury risk in traumatic brain injury. Sci Rep. 2026;DOI:10.1038/s41598-026-57082-4.
Featured Image: stockdevil on Adobe Stock
- Author:
