Abstract
Hyperglycemia is very common in critically ill patients and interventional studies of intensive insulin therapy with the goal of returning ICU glycemia to normal levels have demonstrated mixed results. A large body of literature has demonstrated that diabetes, per se, is not independently associated with increased risk of mortality in this population and that the relationship of glucose metrics to mortality is different for patients with and without diabetes. Moreover, these relationships are confounded by preadmission glycemia; in this regard, patients with diabetes and good preadmission glucose control, as reflected by HbA1c levels obtained at the time of ICU admission, are similar to patients without diabetes. These data point the way toward an era when blood glucose targets in the ICU will be "personalized," based on assessment of preadmission glycemia.