Plasma VGF as a Predictive Biomarker for Early Acute Kidney Injury in Critically Ill Elderly Patients: A Combined Clinical and Mendelian Randomization Study.

OBJECTIVES

To assess whether VGF nerve growth factor inducible (VGF) can serve as a reliable predictor of acute kidney injury (AKI) among patients requiring intensive care.

METHODS

We first conducted a Mendelian randomization (MR) analysis to explore the potential causal link between plasma VGF levels and AKI risk. Subsequently, 128 critically ill individuals admitted to our intensive care unit were prospectively enrolled. Within 24 hours of either hospital admission or clinical decline, both blood and urine specimens were obtained. We measured VGF concentrations in plasma and urine, along with plasma cystatin C (pCysC), plasma and urinary neutrophil gelatinase-associated lipocalin (NGAL), and urinary N-acetyl-β-D-glucosaminidase (NAG). Kidney function was assessed using serum creatinine and hourly urine output. Receiver operating characteristic (ROC) curve analysis was employed to evaluate each biomarker 's predictive capacity for AKI.

RESULTS

The inverse-variance weighted (IVW) method revealed a statistically significant positive association between plasma VGF levels and AKI development. The area under the ROC curve (AUC) values for individual markers were as follows: pVGF (0.651), uVGF (0.483), pCysC (0.750), pNGAL (0.804), uNGAL (0.803), and uNAG (0.632). When pVGF, pCysC, and pNGAL were combined, the AUC increased to 0.861, indicating substantially better predictive performance than any single biomarker.

CONCLUSIONS

Plasma VGF shows promise as a predictive biomarker for AKI in critically ill populations. Its diagnostic utility is considerably strengthened when measured alongside pCysC and pNGAL.