Abstract
<title>Abstract</title> <p>Objective To investigate the association between ultra-early glycaemic variability (UEGV) and clinical outcomes in patients undergoing cardiac valve surgery under cardiopulmonary bypass. Methods Clinical data of patients who underwent cardiac valve surgery were retrospectively analyzed from the MIMIC-IV database. The trend of glycaemic variability (GV) within the first 24 hours postoperatively was observed, and the association between UEGV and the overall trend of GV was explored. Multivariate logistic regression and Cox regression analyses were employed to evaluate the correlations between UEGV and in-hospital mortality, incidence of severe acute kidney injury (AKI), and one-year survival outcomes. Results GV peaked within the first 6 hours after cardiac valve surgery, and the high UEGV cohort consistently maintained a higher level of GV during the subsequent period. Multivariate logistic regression analysis revealed that elevated UEGV was significantly associated with an increased risk of in-hospital mortality (OR = 3.89, 95%CI: 1.35–11.19, P = 0.01), and this effect remained consistent in the isolated valve surgery subgroup. However, no direct association was detected between UEGV and the incidence of severe AKI or one-year survival outcomes (all P > 0.05). Conclusion Elevated ultra-early glycaemic variability after cardiac valve surgery is an independent risk factor for in-hospital mortality. Clinicians should pay close attention to the monitoring and management of ultra-early postoperative glycaemic fluctuations to reduce the risk of in-hospital death.</p>