Intensive care unit outcome in the very elderly.

OBJECTIVES: To determine if age, previous functional status, or acute severity of illness affect the acute and long-term mortality rates and functional status of the very elderly (> or = 85 yrs) after an ICU admission.
DESIGN: Cohort study (retrospective entry for the first year of the study and prospective entry thereafter with prospective follow-up throughout).
SETTING: An ICU in a community teaching hospital with follow-up at home or at a skilled nursing facility. PATIENTS: All (n = 105) patients > or = 85 yrs admitted to the ICU over a 2-yr period. MAIN OUTCOME MEASURES: ICU, 30-day posthospital discharge, and 1-yr mortality rates, activities of daily living scores, organ system failure score at the time of ICU admission.
RESULTS: The ICU, 30-day posthospital discharge, and the 1-yr mortality rates were 30%, 43%, and 64%, respectively. Mortality rates significantly increased between the ICU stay or 30 days posthospital discharge and 1-yr follow-up periods. Of those patients who lived up to 6 months after hospital discharge, 86% survived to 1 yr with little change in functional status from baseline. In the patients with > or = 2 organ system failures, there were 88% 30-day posthospital discharge and 100% 1-yr mortality rates. Severity of illness, as measured by the number of organ system failures, was associated with increased ICU (odds ratio 3.38; 95% confidence interval, 1.51 to 7.60; p < .005) and 1 yr (odds ratio 5.76; 95% confidence interval, 2.49 to 13.29; p < .0001) mortality rates, while age within this group and preadmission functional status were not.
CONCLUSIONS: Within the very elderly population, acute severity of illness is the most significant predictor of mortality after an ICU admission. For most very elderly patients, surviving 1 yr after an ICU admission, there is little change in functional status.