Value of oral glucose tolerance test in the acute phase of myocardial infarction.

Background: Although European guidelines advise oral glucose tolerance test (OGTT) in patients with acute myocardial infarction (AMI) before or shortly after hospital discharge, data supporting this recommendation are inconclusive. We aimed to analyze whether disturbances in glucose metabolism diagnosed before hospital discharge in AMI patients represents a latent pre-existing condition or rather temporary finding. Additionally, we planned to investigate the value of pre-selected glycemic control parameters as predictors of long-term glucometabolic state.

Methods: We assessed admission glycemia, glycated hemoglobin, mean blood glucose concentration on days 1 and 2 in 200 patients with a first AMI but without overt disturbances of glucose metabolism. We also performed OGTT at discharge and 3 months after discharge.

Results: The prevalence of disturbances in glucose metabolism (as assessed by OGTT) at 3 months was significantly lower than at discharge (29% vs. 48%, p = 0.0001). Disturbances in glucose metabolism were not confirmed in 63% of patients with impaired glucose tolerance and in 36% of patients with diabetes mellitus diagnosed during the acute phase of AMI. Age >77 years, glucose ≥ 12.06 mmol/l at 120 minutes during OGTT before discharge and mean blood glucose level on day 2 >7.5 mmol/l were identified as independent predictors of disturbances in glucose metabolism at the 3-month follow-up.

Conclusions: Disturbances in glucose metabolism observed in patients with a first AMI are predominantly transient. Elderly age, high plasma glucose concentration at 120 minutes during OGTT at discharge and elevated mean blood glucose level on day 2 were associated with sustained disturbances in glucose metabolism.