Diabetes does not modify the renal-protective effect of intravenous amino acids infusion after cardiac surgery

Purpose Acute kidney injury (AKI) is a common complication after cardiac surgery and is associated with increased morbidity and mortality. Intravenous amino acids (AA) infusion reduces postoperative AKI. Given the high prevalence of patients with diabetes and their increased susceptibility to renal injury, this study aimed to assess whether the renal-protective effect of AA infusion is maintained in this population. Methods This post-hoc subgroup analysis examined patients with diabetes included in the multinational, double-blind, randomized, placebo-controlled PROTECTION trial. Participants were randomized to receive a continuous intravenous infusion of AA (2 g/kg of the ideal body weight per day; up to 72 h) or placebo during the perioperative period of cardiac surgery. Results Among 644 patients with diabetes (AA n = 309; placebo n = 335), the incidence of any-stage AKI was 43.3% in the AA group versus 47.8% in the placebo group, with no significant interaction observed compared to patients without diabetes (interaction p = 0.82). Similarly, stage 3 AKI occurred in 2.3% of patients in AA group versus 4.8% in the placebo group, with no interaction detected (interaction p = 0.65). Conclusion The beneficial effect of perioperative AA infusion has similar magnitude and direction among patients with or without diabetes. These findings support the use of AA infusion as a renal-protective strategy for all patients undergoing cardiac surgery.