Admission hyperglycemia and all-cause mortality in diabetic and non-diabetic patients with acute myocardial infarction: a tertiary center analysis

Admission hyperglycemia (AH) is associated with worse prognosis in patients with acute myocardial infarction (AMI). Controversy remains whether the impact of AH differs among patients previously diagnosed with diabetes mellitus (DM). We retrospectively evaluated consecutive patients admitted in a coronary care unit with AMI, from 2006 to 2014. Patients were divided into 4 groups: patients without known DM with admission glycemia (AG) ≤ 143 mg/dL (group 1), patients without known DM with AG > 143 mg/dL (group 2), known DM with AG ≤ 213 mg/dL (group 3), and known DM with AG > 213 mg/dL (group 4). Primary outcome was defined as all-cause mortality during follow-up. A total of 2768 patients were included: 1425 in group 1, 426 in group 2, 593 in group 3, and 325 in group 4. After a median follow-up of 5.6 years, 1047 (37.8%) patients reached primary outcome. After multivariate analysis, group 4 was associated with the worst prognosis (HR 3.103, p < 0.001) followed by group 3 (HR 1.639, p = 0.002) and group 2 (HR 1.557, p = 0.039), when compared to group 1. When groups were stratified by type of AMI, patients in group 2 had a worse prognosis than patients in group 3 in the case of non-ST-segment elevation AMI. AH is associated with higher all-cause mortality in patients with AMI, irrespective of previous diabetic status.