Plasma IL-6 and IL-10 Concentrations Predict AKI and Long-Term Mortality in Adults after Cardiac Surgery

Inflammation has an integral role in the pathophysiology of AKI. We investigated the associations of two biomarkers of inflammation, plasma IL-6 and IL-10, with AKI and mortality in adults undergoing cardiac surgery. Patients were enrolled at six academic centers (n = 960). AKI was defined as a ≥ 50% or ≥ 0.3-mg/dl increase in serum creatinine from baseline. Pre- and postoperative IL-6 and IL-10 concentrations were categorized into tertiles and evaluated for associations with outcomes of in-hospital AKI or postdischarge all-cause mortality at a median of 3 years after surgery. Preoperative concentrations of IL-6 and IL-10 were not significantly associated with AKI or mortality. Elevated first postoperative IL-6 concentration was significantly associated with higher risk of AKI, and the risk increased in a dose-dependent manner (second tertile adjusted odds ratio [OR], 1.61 [95% confidence interval (95% CI), 1.10 to 2.36]; third tertile adjusted OR, 2.13 [95% CI, 1.45 to 3.13]). First postoperative IL-6 concentration was not associated with risk of mortality; however, the second tertile of peak IL-6 concentration was significantly associated with lower risk of mortality (adjusted hazard ratio, 0.75 [95% CI, 0.57 to 0.99]). Elevated first postoperative IL-10 concentration was significantly associated with higher risk of AKI (adjusted OR, 1.57 [95% CI, 1.04 to 2.38]) and lower risk of mortality (adjusted HR, 0.72 [95% CI, 0.56 to 0.93]). There was a significant interaction between the concentration of neutrophil gelatinase-associated lipocalin, an established AKI biomarker, and the association of IL-10 concentration with mortality (P = 0.01). These findings suggest plasma IL-6 and IL-10 may serve as biomarkers for perioperative outcomes.