Short-term prognostic factors in the elderly patients seen in emergency departments due to infections

To analyse factors associated with short-term mortality in elderly patients seen in emergency departments (ED) for an episode of infectious disease.

A prospective, observational, multicentre, analytical study was carried out on patients aged 75years and older who were treated in the ED of one of the eight participating hospitals. An assessment was made of 26 independent variables that could influence mortality at 30days. They covered epidemiological, comorbidity, functional, clinical and analytical factors. Multivariate logistic regression analysis was performed.

The study included 488 consecutive patients, 92 (18.9%) of whom died within 30days of visiting the ED. Three variables were significantly associated with higher mortality: severe functional dependence, with Barthel index ≤60 [odds ratio (OR) 8,92; 95% confidence interval (CI): 4.98-15.98, P=.003], systolic blood pressure <90mmHg [OR 7.34; 95%CI: 4.39-12.26, P=.005] and serum lactate >4mmol/l [OR 21.14; 95%CI: 8.94-49.97, P=.001]. The area under the curve for the model was 0.971 (95%CI: 0.951-0.991; P<.001).

Several factors evaluated in an initial assessment in the ED, including the level of functional dependence, systolic blood pressure and, especially, serum lactate, were found to determine a poor short-term prognosis in the elderly patients who presented with an episode of an infectious disease.