Stress hyperglycemia during myocardial infarction (MI) is related to mortality at short and long term. Recent studies, however, revealed that chronic statin treatment may decrease both insulin sensitivity and secretion immediately after statin therapy initiation. This study aim was to investigate the dose-dependent effect of statins on insulin sensitivity in patients in the acute phase of MI.

Stress hyperglycemia during myocardial infarction (MI) is a predictor of worse prognosis at short and long term. From the mechanistic standpoint, hyperglycemia can attenuate thrombolysis, increase platelet aggregation, induce coronary vasoconstriction, reduce oxygen transport and prolong endothelial inflammation after MI. Consistently, observational data indicates that glucose normalization improves survival in hyperglycemic patients hospitalized with MI.

High dose potent statins have been included in the early treatment of acute coronary syndromes (ACS) based upon a broad range of potentially beneficial mechanisms. Recent studies, however, revealed that chronic statin treatment may increase the incidence of type 2 diabetes mellitus in a dose-dependent manner. Moreover, according to studies in cellular and animal models, such decrease in insulin sensitivity may be observed immediately after statin therapy initiation. By inference, one may speculate that statin treatment initiated at the acute phase of MI may potentially favor the appearance or aggravation of stress hyperglycemia. To date, however, this hypothesis has not been investigated. Hence, this study aim was to investigate the dose-dependent effect of statins on insulin sensitivity in patients in the acute phase of MI.

Inclusion Criteria:

• Less than 24 hours after the onset of MI symptoms
• ST-segment elevation of a least 1 mm (frontal plane) or 2 mm (horizontal plane) in two contiguous leads
• Myocardial necrosis, as evidenced by increased Creatine Kinase-MB (CK-MB) and troponin levels

Exclusion Criteria:

• Diabetes or prior use of statins in the last 6 months