One recent ICU study compared the outcomes of patients who developed sub-syndromal delirium (ICDSC 1 to 3) over the course of their ICU stay to those who developed delirium (ICDSC ≥ 4) or who developed neither delirium or subsyndromal delirium (ICDSC = 0). In their study of 537 consecutive, non-comatose patients, 31.5% developed neither clinical delirium or subsyndromal delirium, 33.3% developed subsyndromal delirium (but not clinical delirium) and 35.3% developed clinical delirium. Patients who developed subsyndromal delirium had an ICU mortality rate that was more than 4x greater than patients who developed neither clinical delirium or subsyndromal delirium (10.6% vs 2.4%, p=0.002). In addition, the patients who developed subsyndromal delirium, when compared to those patients without clinical or subsyndromal delirium, had both significantly longer ICU and hospital lengths of stays and were more likely to be discharged to a long-term care facility than home.