Fasting blood glucose at admission is an independent predictor for 28-day mortality in patients with COVID-19 without previous diagnosis of diabetes: a multi-centre retrospective study

Admission biomarkers are increasingly important for risk stratification in patients with COVID-19, helping identify those at higher risk of adverse outcomes. Among these, fasting blood glucose has emerged as a simple and accessible indicator of disease severity. Although elevated glucose levels are commonly linked to diabetes mellitus, they may also occur in non-diabetic patients due to stress-induced metabolic changes during acute illness. Recent evidence suggests that higher fasting blood glucose at admission is associated with increased risk of 28-day mortality. These findings highlight the value of early metabolic assessment in guiding clinical decisions and improving patient management, though further validation is needed.