The prognostic value of blood glucose in diabetic patients with acute myocardial infarction.

The aim of the study was to investigate prospectively the prognostic value of blood glucose on admission in diabetic and non-diabetic patients with an acute myocardial infarction. Three hundred and thirty-three diabetic and 565 non-diabetic patients were admitted with acute myocardial infarction during the study period of 3.5 years. There was a significant association between mortality and blood glucose on admission in diabetic patients (regression coefficient, r = 0.92, 0.5 < p < 0.02) but not in non-diabetic individuals (r = 0.69, 0.2 < p < 0.5). Age- and sex-standardized mortality was higher in the diabetic group (12.2% vs 7.4%, p < 0.03), but was identical if standardized also for blood glucose on admission. We conclude that a high blood glucose on admission is a bad prognostic indicator in a diabetic patient with an acute myocardial infarction. The excess mortality in diabetic patients with acute myocardial infarction can be attributed to the higher proportion with hyperglycaemia.