Acute hyperglycemia (AH) after the onset of acute myocardial infarction (AMI) is a manifestation of transient abnormal glucose metabolism that may reflect AMI severity, and thus be a predictor of poor prognosis. However, it remains unknown whether AH may predict development of de novo diabetes mellitus (dn-DM) in non-diabetic AMI patients.

Among AMI patients registered in the Osaka Acute Coronary Insufficiency Study between 1998 and 2007, we investigated hospital records of 1493 patients who had an admission glycated hemoglobin A1c (HbA1c) level of ≤6.0% and were subjected to glycometabolic profiling after survival discharge. dn-DM was defined as initiation of diabetic medication or documentation of an HbA1c level of ≥6.5% during the 5-year follow-up period. AH, defined as an admission serum glucose level of ≥200 mg/dl, was observed in 133 (8.9%) patients. dn-DM development was more frequent in post-AMI patients with AH than those without [24.8% vs 12.0%, adjusted hazard ratio (HR) 1.776, p = 0.021], particularly among patients with an HbA1c of <5.6% on admission. Treatment with angiotensin-converting enzyme inhibitors or angiotensin receptor blockers was associated with a reduced incidence of dn-DM in patients with AH (adjusted HR 0.397, p = 0.031).

Admission AH was a predictor of dn-DM in non-diabetic post-AMI patients. Renin–angiotensin system inhibitors were associated with reduced incidence of dn-DM in post-AMI patients with AH.