Morbidity and mortality of the old and oldest-old patients in the intensive care unit

Introduction

Demographic changes, new drugs and interventions increase population survival. Elderly patients make up over 25% of patients in the ICU. However, the mortality of elderly ICU patients is controversial. The survival of elderly patients admitted to an ICU in Brazil has not been studied.

Methods

A retrospective study was conducted in a six-bed medical ICU in a tertiary university hospital. We reviewed all patients admitted from August 2003 to January 2007; 1,179 patients were included in the study. The APACHE II score and preview mortality were assessed at the first 24 hours in the ICU. Demographic data, previous medical history, reasons for admission to the ICU, length of stay in the ICU, survival rate and standardized mortality ratio (SMR) were also researched.

Results

The mean age was 54.0 ± 19.8 years, 52.3% were female and most of patients originated from hospital (51.8%). The APACHE II score was 18.3 ± 8.3 points. The length of stay in the ICU was 6.6 ± 7.4 days and mortality was 34.9%, 3.9% before 48 hours. The SMR was 1.04. In the group of old patients (≥65 years old, n = 416), the mean APACHE II score was 19.5 ± 7.6 points. Respiratory insufficiency, sepsis and acute coronary syndrome were the most frequent reasons for admission (18%, 16.8% and 14.4%, respectively). Mortality in this group was 37.0% (chi-square test; P = 0.2506), 4.3% at the first 48 hours, and the SMR was 1.06. Length of stay in the ICU was 6.6 ± 5.8 days (P > 0.05). In the oldest-old patient group (≥85 years old, n = 37), the mean APACHE II score was 18.4 ± 4.9. Sepsis and respiratory insufficiency were the principal reasons for admission (21.6% and 13.5%, respectively), with no coronary patient admitted. Mortality was 35.1% (chi-square test; P = 0.9803), 5.4% in the first 48 hours, and the SMR was 1.27. The length of stay was 6.5 ± 3.9 days (P > 0.05).

Conclusion

Old age was not associated with a high fatal outcome or length of stay in ICU. However, mortality in patients aged 85 years or more was higher than expected. The APACHE II score could allow an early identification of patients at high risk of death, even in old and oldest-old patients. A prospective assessment is mandatory to confirm these preliminary data.