Epidemiological and clinical management aspects of pneumonias diagnosed in the emergency department in elderly patients in Spain: Results of the EDEN-29 study.

Objectives: To estimate the incidence of pneumonia diagnosis in elderly patients in Spanish emergency departments (ED), need for hospitalization, adverse events and predictive capacity of biomarkers commonly used in the ED.

Methods: Patients ≥65 years with pneumonia seen in 52 Spanish EDs were included. We recorded in-hospitaland 30-day mortality as adverse events, as well as intensive care unit (ICU) admission among hospitalizedpatients. Association of 10 predefined variables with adverse events was calculated and expressed as odds ratio (OR) with 95% confidence interval (CI), as well as predictive capacity of 5 commonly used biomarkers in the ED (leukocytes, hemoglobin, C-reactive protein, glucose, creatinine) was investigated using area under the receiver operating characteristic curve (AUC-ROC).

Results: 591 patients with pneumonia attended in the ED were included (annual incidence of 18,4 per 1000 inhabitants). A total of 78.0% were hospitalized. Overall, 30-day mortality was 14.2% and in-hospital mortality was 12.9%. Functional dependency was associated with both events (OR=4.453, 95%CI=2.361-8.400; and OR=3.497, 95%CI=1.578-7.750, respectively) as well as severe comorbidity (2.344, 1.363-4.030, and 2.463, 1.252-4.846, respectively). Admission to the ICU during hospitalization occurred in 3.5%, with no associated factors. The predictive capacity of biomarkers was only moderate for creatinine for ICU admission (AUC-ROC=0.702, 95% CI=0.536-0.869) and for leukocytes for post-discharge adverse event (0.669, 0.540-0.798).

Conclusions: Pneumonia is a frequent diagnosis in elderly patients consulting in the ED. Their functional dependence and comorbidity is the factor most associated with adverse events. The biomarkers analyzed do not have a good predictive capacity for adverse events.