Mortality risk factors in elderly patients in intensive care without limitation of therapeutic effort

Abstract

Outcome: To determine mortality prognostic factors in elderly patients who are admitted to intensive care units (ICUs) due to acute critical illness.

Design: A prospective cohort study was carried out.

Setting: A polyvalent Intensive Care Unit at a University Hospital in Argentina.

Patients or participants: We included 249 patients over 65years of age who were consecutively admitted to the ICU and required mechanical ventilation for more than 48hours, between January 2011 and December 2012. Patients with degenerative neurological disease, limitation of therapeutic effort or on chronic mechanical ventilation were excluded.

Principal variables of interest: In-hospital mortality, comorbidity (Charlson index), APACHEII score, and pre-acute illness status were recorded: nutritional status (subjective global assessment), functionality (activities of daily living [ADL] and Barthel index), cognitive abilities (Short Reporting Questionnaire on Cognitive Decline in the Elderly [S_IQCODE]) and quality of life (EQ-5D).

Results: The in-hospital mortality rate was 52%. Logistic regression analysis, after adjusting for APACHEII score and age, identified the following independent variables associated to mortality: male gender (OR: 2.46, 95%CI: 1.37-4.42), moderate malnutrition (OR: 2.07, 95%CI: 1.09-3.94), severe malnutrition (OR: 2.20, 95%CI: 1.06-4.59), and ADL<6 (OR: 2.35, 95%CI: 1.16-4.75).

Conclusions: In our study, chronological age was not associated to in-hospital mortality. However, loss of functional independence (assessed by ADL) and malnourishment were shown to be strong prognostic factors; knowing these baseline characteristics from ICU admission would be useful when making decisions regarding the intensity of treatment.

Keywords: Actividades de la vida diaria; Activities of daily living; Anciano; Critical illness; Elderly; Enfermedad crítica; Hospital mortality; Mortalidad hospitalaria.