Trends in the Use of Intensive Care by Very Elderly Patients and Their Clinical Course in a Single Tertiary Hospital in Korea

Background: The number of elderly patients admitted to intensive care units (ICUs) is growing with the increasing proportion of elderly persons in the Korean general population. It is often difficult to make decisions about ICU care for elderly patients, especially when they are in their 90s. Data regarding the proportion of elderly patients in their 90s along with their clinical characteristics in ICU are scarce. Methods: The records of Korean patients ≥ 90 years old who were admitted to the medical ICU in a tertiary referral hospital between January 2005 and December 2014 were retrospectively reviewed. We compared the trend in ICU use and characteristics of these elderly patients between 2005-2009 and 2010-2014. Results: Among 6,186 referred patients, 55 aged ≥ 90 years were admitted to the medical ICU from 2005 to 2014. About 58.2% of these patients were male, and their mean age was 92.7 years. Their median Charlson comorbidity index score was 2 (IQR 1-3) and their mean APACHE II score was 25.0 (IQR 19.0-34.0). The most common reason for ICU care was acute respiratory failure. There were no differences in the survival rates between the earlier and more recent cohorts. However, after excluding patients who had specified “do not resuscitate” (DNR), the more recent group showed a significantly higher survival rate (53.8% mortality for the earlier group and 0% mortality for the recent group). Among the survivors, over half were discharged to their homes. More patients in the recent cohort (n=26 [78.8%]) specified DNR than in the earlier cohort (n=7 [35.0%], p=0.004). The number and proportion of patients ≥ 90 years old among patients using ICU during the 2005-2014 study period did not differ. Conclusions: The use of ICU care by elderly patients ≥ 90 years old was consistent from 2005-2014. The overall mortality rate tended to decrease, but this was not statistically significant. However, the proportion of patients specifying DNR was higher among more recent patients, and the recent group showed an even better survivorship after sensitivity analysis excluded patients specifying DNR.