Aims In acute myocardial infarction (AMI), baseline hyperglycaemia predicts adverse outcomes, but the relation between subsequent change in glucose levels and outcomes is unclear. We evaluated the prognostic significance of baseline glucose and the change in glucose in the first 24 h following AMI.

Methods and results We analysed 1469 AMI patients with baseline and 24 h glucose data from the CARDINAL trial database. Baseline glucose and the 24 h change in glucose (24 h glucose level subtracted from baseline glucose) were included in multivariable models for 30- and 180-day mortality. By 30 and 180 days, respectively, 45 and 74 patients had died. In the multivariable 30-day mortality model, neither baseline glucose nor the 24 h change in glucose predicted mortality in diabetic patients (n=250). However, in nondiabetic patients (n=1219), higher baseline glucose predicted higher mortality [hazard ratio (HR) 1.12, 95% confidence interval (CI) 1.04–1.20, per 0.6 mmol/L increase], and a greater 24 h change in glucose predicted lower mortality (HR 0.91, 95% CI 0.86–0.96, for every 0.6 mmol/L drop in glucose in the first 24 h) at 30 days. Baseline glucose and the 24 h change in glucose remained significant multivariable mortality predictors at 180 days in nondiabetic patients.

Conclusion Both higher baseline glucose and the failure of glucose levels to decrease in the first 24 h after AMI predict higher mortality in nondiabetic patients.