The paper by Morandi et al. (2011), entitled “Insulin-like growth factor-1 and delirium in critically ill mechanically ventilated patients: a preliminary investigation,” is of great interest due to its lack of finding a correlation between serum levels of insulin-like growth factor-1 (IFG-1) and delirium in intensive care unit (ICU) patients. As reviewed recently by Adamis and Meagher (2011), a...