Purpose of review: Hyperglycemia, hypoglycemia and increased glycemic variability are independently associated with increased risk of mortality in critically ill patients. The purpose of this review is to evaluate the evidence from interventional trials of intensive insulin therapy, as well as observational cohort studies, relating premorbid diabetic status and these three domains of glycemic control to mortality.
Recent findings: Hyperglycemia has a stronger association with mortality in critically ill patients without diabetes than in those with diabetes. Hypoglycemia is independently associated with increased risk of mortality in both populations. Limited data suggest that increased glycemic variability may have a stronger association with mortality in patients without diabetes than in those with diabetes.
Summary: Premorbid diabetic status impacts the relationship of the three domains of glycemic control to risk of mortality in critically ill patients. The data presented in this review are hypothesis generating; future trials of IIT in the critically ill should stratify management and outcomes by premorbid diabetic status.