Stress hyperglycemia exceeds known diabetes in predicting in-hospital mortality after acute myocardial infarction: An 11-year national study of 13,099 patients

Abstract Stress hyperglycemia exceeds known diabetes in predicting in-hospital mortality after acute myocardial infarction: An 11-year national study of 13,099 patients Background Diabetes mellitus (DM) is a well-established risk factor for adverse outcomes after acute myocardial infarction (AMI). However, the prognostic impact of stress hyperglycemia in non-diabetic patients remains incompletely characterized, particularly in transitional healthcare systems. Aim To evaluate the clinical profile, management, temporal trends, and in-hospital outcomes of AMI patients according to known diabetes status and admission stress hyperglycemia in a nationwide 11-year cohort. Methods We analyzed 13,099 consecutive AMI patients hospitalized between 2014–2024 at Kosovo’s main tertiary cardiology center. Patients were classified as known diabetes or no known diabetes. Among non-diabetics, stress hyperglycemia was defined as admission glucose >11.1 mmol/L. Clinical characteristics, invasive management, and in-hospital mortality were compared. Annual trends were assessed using logistic regression. Results Known diabetes was present in 36.3% (n=4,759) of patients. Diabetic patients were older, more frequently female, and had higher prevalence of hypertension and reduced LVEF (all p<0.001). They underwent less coronary angiography (67.8% vs 71.9%) and PCI (48.4% vs 55.6%; both p<0.001) and had higher in-hospital mortality (11.0% vs 6.7%; p<0.001). Among non-diabetics (n=8,340), 641 (7.7%) presented with stress hyperglycemia. This group had markedly higher mortality compared with normoglycemic non-diabetics (22.2% vs 4.2%; p<0.001) and even higher than known diabetics (22.2% vs 11.0%). They also had lower LVEF, worse renal function, and underwent less PCI (52.7% vs 60.6%; p<0.001). The proportion of AMI patients with known diabetes increased significantly over time (OR per year 1.032; 95% CI 1.019–1.045; p<0.001). Conclusions In this large real-world AMI cohort, both known diabetes and stress hyperglycemia were associated with worse in-hospital outcomes. Importantly, stress hyperglycemia identified a highest-risk phenotype with mortality exceeding that of established diabetes. These findings highlight the need for systematic glycemic assessment and aggressive metabolic management in all AMI patients, regardless of diabetes history.