Critically ill old and the oldest-old patients in intensive care: short- and long-term outcomes

Objective. The purpose of this study was to examine characteristics and outcome of the old, very old and oldest-old ICU patients. Design. This is a cohort study. Setting. The study was set in a ten-bed medical ICU in a university hospital. Participants. There were 410 patients classified in three subgroups: old, 75-79 years (n=184; 44.4%), very old, 80-84 (n=137, 33.4%) and the oldest-old, greater than or equal to85 (n=91; 22.2%). Measurements. Underlying medical conditions, organ dysfunction, severity of illness, length of stay, use of mechanical ventilation, therapeutic activity and nosocomial infections were recorded. Multivariate analysis was conducted to identify risk factors for ICU and long-term mortality. Results. Characteristics at ICU admission did not differ among the three groups. ICU length of stay, therapeutic activity, mechanical ventilation and nosocomial infection(s) decreased with age. ICU survival rates for those below 75, 75-79, 80-84 and over 85 years were 80, 68, 75 and 69%, respectively; survival rates at 3 months were 54, 56 and 51%, respectively. APACHE II score [odds ratio (OR): 1.11] was identified as the only factor associated with ICU mortality, and age (OR: 2.17, for patients greater than or equal to85 years old and 1.82, for patients 80-84 years old) and limitation of activity before admission (OR: 1.74) as factors associated with long-term mortality. Conclusion. In a population of patients greater than or equal to75 years old, very old age is not directly associated with ICU mortality. After ICU discharge, deaths occurred predominantly during the first 3 months: age and prior limitation of activity were associated with the risk of dying.