Effect of blood glucose levels on prognosis in acute myocardial infarction in patients with and without diabetes, undergoing percutaneous coronary intervention.

Background: Diabetes mellitus (DM) is a significant factor regarding poor outcome in patients with myocardial infarction. Recently a new prognostic factor is under consideration - a baseline glucose level on admission. We sought to assess the influence of blood glucose levels on admission on prognosis of patients with acute ST-segment elevation myocardial infarction (STEMI) treated with percutaneous coronary intervention (PCI).
Methods and Results: Consecutive patients treated with PCI for STEMI were analyzed. Presence or absence of DM was the first grouping criterion. The secondary criterion was the blood glucose level on admission [threshold >or= 7.8 mmol/L (140 mg/dL)]. Hyperglycemic and non-hyperglycemic subgroups were selected within both DM and non-DM groups according to the threshold. One-year mortality of diabetics was 16.0%. There was no significant difference in 1-year mortality between hyperglycemic and non-hyperglycemic patients with DM. One-year mortality in the non-DM group was 5.6%. Patients without DM but with hyperglycemia showed a higher 1-year mortality rate than non-hyperglycemic patients (8.51% vs. 3.68%, p = 0.001). Multivariate analysis revealed that in the non-DM group blood glucose level (per 1 mmol/L) on admission was a factor affecting 1-year mortality [HR = 1.09 (1.01-1.17)].
Conclusions: Elevated blood glucose levels in STEMI affect the prognosis of patients without DM; however, it is not an independent death risk factor of patients with DM treated with PCI.