Relative Hyperglycemia, a Marker of Critical Illness: Introducing the Stress Hyperglycemia Ratio

Context: Hyperglycemia in hospitalized patients is associated with increased morbidity and mortality. Objective: We examined whether critical illness is more strongly associated with relative or absolute hyperglycemia. Design: The study was an observational cohort study. Patients and Setting: A total of 2290 patients acutely admitted to a tertiary hospital. Main Outcome Measure: The relative hyperglycemia (stress hyperglycemia ratio [SHR]) was defined as admission glucose divided by estimated average glucose derived from glycosylated hemoglobin. The relationships between glucose and SHR with critical illness (in-hospital death or critical care) were examined. Results: In univariable analyses, SHR (odds ratio, 1.23 per 0.1 increment [95% confidence interval, 1.18–1.28]; P < .001) and glucose (odds ratio, 1.18 per mmol/L [1.13–1.23]; P < .001) were associated with critical illness. In multivariable analysis, the association was maintained for SHR (odds ratio, 1.20 per 0.1 increment [1.13–1.28]; P < .001), b...