Oxidative stress promotes acute kidney injury (AKI). Higher concentrations of HDL cholesterol are associated with less AKI. To test the hypothesis that HDL antioxidant activity is associated with AKI after cardiac surgery, we quantified HDL particle size and number, paraoxonase-1 activity, and isofuran concentrations in 75 patients who developed AKI and 75 matched control patients. Higher preoperative concentrations of HDL particles were associated with lower odds of AKI (OR: 0.80; 95% CI, 0.71-0.91; p=0.001), higher paraoxonase-1 activity (R=0.36, p<0.001), and lower plasma concentrations of isofurans immediately after surgery (p=0.02). Similarly, higher preoperative small HDL particle concentrations were associated with less AKI, higher paraoxonase-1 activity, and lower isofuran concentrations. Circulating HDL particle concentrations changed rapidly during the perioperative period. Higher intraoperative particle losses were associated with lower odds of AKI (OR: 0.79; 95% CI 0.67-0.93; p=0.005), and increased paraoxonase-1 activity strengthened this association (p=0.006). Intraoperative particle loss was also associated with decreased postoperative isofuran concentrations (p=0.04). Additionally, higher preoperative small HDL particle concentrations and increased intraoperative small particle loss were associated with improved renal function 3-12 months after surgery (p=0.003, 0.01, respectively). In conclusion, a higher preoperative concentration of HDL particles, particularly small particles, is associated with lower oxidative damage and less AKI. Perioperative changes in HDL particle concentrations are also associated with AKI. Small HDL particles may represent a novel modifiable risk factor for AKI.
Copyright © 2021 The Authors. Published by Elsevier Inc. All rights reserved.

Author