A Literature Review of Intensive Insulin Therapy and Mortality in Critically Ill Patients

Background: Since Van den Berghe et al published their study on tight glucose control in 2001, intensive insulin therapy (IIT) has been increasingly used for critically ill patients worldwide. However, recent studies reported a significantly increased risk of hypoglycemia without a significant reduction in mortality. Objective: The purpose of this article was to evaluate the effect of IIT with a target glucose of 110 mg/dL or less on mortality in adult critically ill patients and to determine whether it is appropriate to generalize IIT for all critically ill patients. Methods: Ovid, MEDLINE, and PubMed databases were searched for studies that compared "conventional" vs "intensive" insulin therapy in adult critically ill patients. Results: Eleven articles were included for this review. There was no significant difference in intensive care unit mortality between tight glucose control group and conventional glucose control group in 5 of 6 studies. Only 1 study showed a significant difference in hospital mortality between the 2 groups. Seven studies showed a significant increase in the incidence of hypoglycemia. Conclusions: Intensive insulin therapy was not associated with significant reduction in mortality in adult critically ill patients but was related to a significant increase in the incidence of hypoglycemia. Therefore, it is inappropriate to generalize IIT for all critically ill patients, even though it significantly improved blood glucose control.