[Functional status as an independent risk factor in elderly patients admitted to an Intensive Care Unit]

Abstract

Objective: To assess the association of previous functional status in elderly patients admitted to the ICU, estimated by the Barthel and Short Form-Late Life Function and Disability instrument scales, and the relationship with prognosis and functional capacity at hospital discharge.

Material and methods: Observational prospective study of ICU-admitted patients older than 74 years, with a length of stay greater than 48hours. Demographic data, social background, comorbidities, disability questionnaire (Barthel, Short Form-Late Life Function and Disability instrument), main diagnosis and severity (SAPS 3) on ICU admission were recorded. Factors associated with mortality or poor functional status at hospital discharge (Barthel Index less than 35) were established by multivariate analysis.

Results: During the study period, 219 elderly patients were admitted in ICU, of whom 129 (15%) had an ICU length of stay greater than 48hours. The median age was 80 years (77-83), with 52% women. Main diagnoses on admission included ischaemic heart disease (19%), another medical diagnosis (38%), and surgical procedure (43%). A Barthel score <36 (median 95, 85-100) was observed in 3% of the patients on admission. The median ICU length of stay was 5 days (4-8). ICU mortality was 6% (hospital mortality: 10%). On hospital discharge, 7% had severe dependence (Barthel <36). In this population, factors independently associated with mortality or poor functional status at hospital discharge were the pre-admission functional status, based on Short Form-Late Life Function and Disability instrument (OR 0.95, 95% CI, 0.91 to 0.98), and the severity on admission assessed by SAPS 3 (OR 1.10, 95% CI, 1.02 to 1.18), p=.0007.

Conclusions: In elderly patients requiring ICU admission, a higher SAPS 3 score and functional impairment on admission were associated with mortality or severe dependence upon discharge.

Keywords: Anciano; Critical illness; Fragilidad; Frail elderly; Geriatric assessment; Outcome assessment; Pronóstico; Unidad de Cuidados Intensivos.