Nyström T, James SK, Lindahl B, et al. - In myocardial infarction (MI) patients with and without diabetes, researchers conducted this Determination of the Role of Oxygen in Suspected Acute Myocardial Infarction (DETO2X-AMI) trial to identify the impacts of oxygen therapy. Six thousand six hundred twenty-nine normoxemic patients with suspected MI were randomized to oxygen at 6 L/min for 6–12 h or ambient air. In this prespecified analysis including 5,010 patients with confirmed MI, 934 had known diabetes. As anticipated, in patients with diabetes, event rates were considerably greater than in patients without diabetes. The main composite endpoint occurred in 16.2% allocated to oxygen as compared with 16.6% allocated to ambient air in patients with diabetes. No statistically significant difference was observed for the individual components of the composite endpoint or the rate of cardiovascular death up to 1 year. Similarly, the respective endpoints between treatment groups in patients without diabetes were comparable. Despite significantly higher incidence rates in MI and diabetes patients, oxygen therapy did not significantly affect 1-year all-cause death, cardiovascular death, or MI or heart failure rehospitalization, regardless of underlying diabetes, in line with the results of the entire study.