443-P: Reduced Cardiorenal Function and In-Hospital Mortality in Patients with Type 2 Diabetes Mellitus and ST-Segment Elevation Myocardial Infarction

Background: ST-segment elevation myocardial infarction (STEMI) patients with diabetes mellitus (DM) have higher in-hospital mortality than those without. Since cardiac and renal functions are the main variables associated with outcome in STEMI, we hypothesized that this prognostic disparity may depend on a higher rate of cardiac and renal dysfunction in DM patients.

Methods: We included 5,152 STEMI patients treated with primary angioplasty. Left ventricular ejection fraction (LVEF) and estimated glomerular filtration rate (eGFR) were evaluated at hospital admission. The primary endpoint was in-hospital mortality. A composite of in-hospital mortality, cardiogenic shock, and acute kidney injury was the secondary endpoint.

Results: Eight-hundred-seventy-nine (17%) patients had DM. The incidence of LVEF≤40% (30% vs. 22%; P<0.001), eGFR≥60 ml/min/1.73m² (27% vs. 18%; P<0.001), or both (12% vs. 6%; P<0.001) was higher in patients with DM. In-hospital mortality was higher in DM than in non-DM patients (6.1% vs. 3.5%; P=0.002) with an unadjusted OR of 1.81 (95% confidence interval [CI] 1.31-2.50; P=0.003). However, DM was no longer associated with an increased mortality risk after adjustment for cardiac and renal function (OR 1.03, 95% CI 0.68-1.56; P=0.89). A similar behavior was observed for the secondary endpoint, with an unadjusted OR for DM of 1.52 (95% CI 1.25-1.85; P<0.001) and an OR after adjustment for cardiac and renal function of 1.07 (95% CI 0.85-1.36; P=0.53).

Conclusion: The study indicates that the increased in-hospital mortality and morbidity of DM patients with STEMI is driven by the underlying cardio-renal dysfunction, rather than to the mere presence of DM.