Glucagon-like peptide-1 (GLP-1) levels are associated with acute kidney injury after cardiac surgery

Acute kidney injury (AKI) is a frequent and clinically relevant complication after cardiac surgery. Early prediction remains challenging because serum creatinine is a delayed and insensitive marker of renal dysfunction. Glucagon-like peptide-1 (GLP-1) and glucose-dependent insulinotropic polypeptide (GIP) are incretin hormones with established metabolic functions and emerging roles in cardiovascular, renal, and critical illness–related pathophysiology, and their perioperative association with AKI remains incompletely characterised. In this prospective single-centre observational study, 107 adults undergoing elective cardiac surgery were enrolled. Serum GLP-1 and GIP were measured at four time points (preoperatively, immediately postoperatively, and on postoperative days 1 and 4). AKI was defined according to KDIGO criteria. Subgroup analyses excluded patients with chronic kidney disease (CKD). Postoperative AKI occurred in 21 patients (19.6%), predominantly KDIGO stage 1. These patients had longer ICU stays (5 [2–12] vs. 3 [1–10] days; p < 0.001), higher SAPS II scores (35 [28–39] vs. 29 [25–33]; p = 0.027), and higher SOFA scores on postoperative days 1 and 4 (both p < 0.05). Preoperative GLP-1 levels were significantly elevated in patients who developed AKI (38.3 [30–52] vs. 27.4 [16.7–48.9] pmol/L; p = 0.04), whereas baseline creatinine and GIP did not differ. The association between GLP-1 and AKI remained significant after excluding patients with CKD. Preoperative endogenous GLP-1 levels were associated with postoperative AKI and were elevated earlier in the perioperative course compared with serum creatinine, particularly in patients without CKD. These findings suggest that GLP-1 may reflect early renal stress or vulnerability and warrant further investigation in larger cohorts.