Performances of acute kidney injury biomarkers vary according to sex

Area of Science:

• Investigates sex-based molecular differences in acute kidney injury (AKI) pathophysiology.
• Focuses on patients undergoing cardiac bypass surgery (CBP).
• Utilizes advanced urinary peptide analysis for biomarker discovery.

Background:

• Individualized treatment for AKI requires understanding patient subgroups with distinct mechanisms.
• Cardiac bypass surgery is a significant risk factor for AKI.
• Previous studies have not fully elucidated sex-specific molecular pathways in CBP-associated AKI.

Purpose of the Study:

• To identify sex-related molecular mechanisms in patients developing AKI after CBP surgery.
• To compare the diagnostic performance of urinary biomarkers between sexes.
• To explore potential sex-specific pathophysiological differences in AKI.

Main Methods:

• Compared characteristics of 1170 patients undergoing CBP surgery.
• Employed multivariate logistic regression and propensity score-based analysis.
• Assessed urinary neutrophil gelatinase-associated lipocalin (uNGAL), NephroCheck ([IGFBP7]·[TIMP-2]), and an AKI signature (AKI204) for AKI prediction in both sexes.

Main Results:

• AKI incidence and severity were similar between men and women post-CBP, even after risk factor adjustment.
• Biomarker performance for AKI prediction (uNGAL, NephroCheck, AKI204) significantly diverged between sexes.
• The AKI204 peptide signature outperformed other biomarkers and predicted AKI better in women, suggesting increased kidney inflammation in women.

Conclusions:

• Significant clinical and biological differences exist between men and women undergoing CBP surgery.
• Sexual dimorphism in AKI biomarker performance was identified.
• The urinary peptide signature highlights sex-related molecular mechanisms underlying AKI development.