Impact of diabetes and ejection fraction on non-ST-Segment elevation myocardial infarction outcomes

Given the limited published data, we examined three-year outcomes in patients with and without diabetes mellitus (DM) in non-ST-segment elevation myocardial infarction (NSTEMI), according to left ventricular ejection fraction (LVEF). A total of 4594 patients were classified into DM (n = 1608) and non-DM (n = 2986) groups. They were further classified into heart failure with reduced EF (HFrEF, LVEF ≤ 40%), HF with mildly reduced EF (HFmrEF, LVEF 41-49%), and HF with preserved EF (HFpEF, LVEF ≥ 50%) subgroups. The primary outcome was all-cause mortality, and secondary outcomes included cardiac death (CD), non-CD (NCD), recurrent MI, any revascularization, and hospitalization for HF (HHF). In both DM and non-DM groups, in-hospital all-cause mortality rates were higher in the HFrEF subgroup than in the HFmrEF and HFpEF subgroups, but were similar between the HFmrEF and HFpEF subgroups. In the DM group, the three-year all-cause mortality (P < 0.001 for both), CD, NCD, recurrent MI, and HHF rates were higher in the HFrEF subgroup than in the HFmrEF and HFpEF subgroups. In the non-DM group, the three-year all-cause mortality (P = 0.001 and P < 0.001, respectively), CD, and HHF rates were higher in the HFrEF subgroup than in the HFmrEF and HFpEF subgroups. In both DM and non-DM groups, the three-year all-cause mortality and NCD rates were higher in the HFmrEF group than in the HFpEF group. Regardless of the presence of DM, the three-year outcomes were best in HFpEF, worst in HFrEF, and intermediate in HFmrEF patients.