Risk for early death in acutely ill older adults attended by prehospital emergency medical services

Objective. To develop and validate a prehospital risk model to predict early in -hospital mortality (548 hours) in patients aged 65 years or older. Methods. Prospective multicenter observational study in a cohort of patients aged 65 years or older attended by advanced life support emergency services and transferred to 5 Spanish hospitals between April 2018 and July 2019. We collected demographic, clinical and laboratory variables. A risk score was constructed and validated based on the analysis of prehospital variables associated with death within 48 hours. Predictors were selected by logistic regression. Results. A total of 1759 patients were recruited. The median age was 79 years (interquartile range, 72-85 years), and 766 (43.5%) were women. One hundred eight patients (6.1%) died within 48 hours. Predictors in the Prehospital Older Adults Warning Scale (POAWS) were age, systolic blood pressure, temperature, the ratio of oxygen saturation to the fraction of inspired oxygen, score on the Glasgow coma scale, and lactic acid concentration in venous blood. The area under the receiver operating characteristic curve of the model to predict early mortality was 0.853 (95% CI, 0.80-0.91; P<.001). Mortality in patients at high risk (POAWS score, >7) was 69%. Conclusions. The prehospital POAWS score can be used to stratify risk for death within 48 hours in patients aged 65 years or older.