Sex-specific impact of glycemic variability on long-term outcomes after acute myocardial infarction

Acute myocardial infarction (AMI) remains a major cause of global morbidity and mortality. Glycemic variability (GV), reflecting fluctuations in blood glucose levels, has emerged as a prognostic marker in critically ill patients. However, evidence on the sex-specific impact of GV on long-term outcomes after AMI is limited. To evaluate the association between GV and short- and long-term mortality after AMI, with emphasis on sex-based differences. Data of 1666 AMI patients were extracted from a public critical care database. GV was calculated as the coefficient of variation of plasma glucose levels during ICU stay. Patients were divided into tertiles by GV and analyzed by sex. Kaplan–Meier survival, multivariable Cox regression, restricted cubic spline (RCS), and receiver operating characteristic (ROC) analyses were performed. Higher GV was associated with increased 12-month mortality, particularly in males. In adjusted models, each unit increase in GV was independently associated with higher 12-month mortality in the total cohort (HR = 1.01, P = 0.001) and in males (HR = 1.02, P < 0.001), but not in females. A significant interaction between GV and sex was observed (Pinteraction < 0.05). RCS curves demonstrated a positive linear relationship between GV and mortality risk, more evident in males. ROC analyses showed a modest but significant improvement in the predictive performance of GV for both 1-month and 12-month mortality in males. GV was independently associated with long-term mortality in AMI, with a more consistent association in men. These findings highlight the need for sex-specific glucose management strategies in critically ill cardiovascular patients.