Diabetes mellitus unawareness is a strong determinant of mortality in patients manifesting myocardial infarction.

OBJECTIVE: Often, as diabetes mellitus type 2 (T2DM) evolves insidiously, prevention is commenced late and diagnosis is made when vascular damage has been set. Hence, our hypothesis is that T2DM awareness may influence the outcome of atherothrombotic events. METHODS: A consecutive cohort of patients manifesting ST-elevation myocardial infarction (MI) was classified according to the presence and awareness of the diagnosis of T2DM: known diabetes (kT2DM, n = 72), unknown diabetes (uT2DM, n = 80) and no diabetes (ND, n = 333). Medical history, laboratory data, and angiographic findings including myocardial blush grade (MBG) were prospectively obtained. The primary endpoint was in-hospital death and secondary endpoint was major adverse cardiac events (MACE) defined as sudden cardiac death, fatal MI and nonfatal MI that occurred from 30 days of study entry onwards. RESULTS: With the exception of glycated hemoglobin (p = 0.001) and triglycerides (p = 0.04), no differences were found between groups for all other biochemical, clinical or angiographic admission characteristics. Myocardial tissue reperfusion defined as MBG 3 was observed in 62% in the ND group, 50% in the kT2DM group and 23% in the uT2DM group (p = 0.01). All-cause in-hospital mortality was higher in uT2DM (16.7%) than in kT2DM (8.4%) and both groups had a higher mortality rate as compared with the ND group (3.8%, p = 0.01). During follow-up (653 ± 26 days), the incidence of MACE was higher in uT2DM than in kT2DM and in both compared to the ND group (p = 0.002). CONCLUSION: Unawareness of T2DM diagnosis is strongly associated with a poor short- and long-term outcome after MI.