Diabetes Mellitus is Associated with Increased Mortality after Acute Myocardial Infarction Only in Patients with Preserved Left Ventricular Systolic Function

Abstract

Background Left ventricular (LV) systolic function and diabetes mellitus (DM) are the primary determinants of clinical outcomes in patients with acute myocardial infarction (AMI). This study investigated the impact of DM on mortality according to LV systolic function after AMI. Methods Between November 2005 and September 2009, a total of 12,486 patients from a nationwide database, who survived 30 days after AMI, were included in the study. Patients were stratified into two groups according to their LV ejection fraction (LVEF): LVEF<40% (n=1,732, 13.9%) and LVEF≥40% (n=10,754, 86.1%), and the effect of DM was analyzed in each group. Results DM was more prevalent in patients with LVEF<40% than in those with LVEF≥40% (n=622, 36.1% vs n=2786, 25.9%

P<0.001). The 12-month mortality was higher in patients with with LVEF<40% than in those with LVEF≥40% (8.2% vs 2.0%, P<0.001) and DM than in those without DM (7.2% vs 10.1%, P=0.012

1.6% vs 3.1%, P<0.001). In multivariate analysis, DM was an independent predictor of mortality in the LVEF ≥40% group (HR: 1.75

95% CI: 1.23–2.49

P=0.002), but not in the LVEF<40% group (HR: 1.21

95% CI: 0.80–1.83

P=0.364). Conclusions DM was a significant independent risk factor for 12-month mortality in patients with LVEF≥40% but not in those with LVEF<40% after AMI.