Glucose variability during delirium in diabetic and non-diabetic intensive care unit patients: A prospective cohort study

PURPOSE: To determine whether glucose variability is altered during delirium days compared to non-delirious days in critically ill patients with and without diabetes in the intensive care unit (ICU). MATERIALS AND METHODS: Critically ill patients with delirious and non-delirious days during ICU stay were included from a prospective cohort study which was conducted from January 2011- June 2013. Glucose variability was measured each observation day using various definitions (change in mean glucose, standard deviation, mean absolute glucose, daily delta and occurrence of hypo- and hyperglycemia). Mixed-effects models and generalized mixed-effects models with logit link function were performed to study the association between delirium and glucose variability, adjusting for potential confounders. RESULTS: With the exception of the risk of hypoglycemia, delirium was not linked to higher glucose variability using the various definitions of this estimate. For hypoglycemia, we did find an association with delirium in diabetic patients (OR adj.: 2.78; 95% CI: 1.71–6.32, p = 0.005), but not in non-diabetic patients (OR adj.: 1.16; 95% CI: 0.58–2.28, p = 0.689). CONCLUSIONS: Despite the positive association between delirium and hypoglycemia in critically ill patients with diabetes, delirium was not associated with more pronounced glucose variability. Our findings suggest that glucose levels should be monitored more closely in diabetic patients during delirium at the ICU to prevent hypoglycemia.