Mortality of older acutely admitted medical patients after early discharge from emergency departments: a nationwide cohort study

BACKGROUND: The mortality of older patients after early discharge from hospitals is sparsely described. Information on factors associated with mortality can help identify high-risk patients who may benefit from preventive interventions. The aim of this study was to examine whether demographic factors, comorbidity and admission diagnoses are predictors of 30-day mortality among acutely admitted older patients discharged within 24 h after admission. METHODS: All medical patients aged ≥65 years admitted acutely to Danish hospitals between 1 January 2013 and 30 June 2014 surviving a hospital stay of ≤24 h were included. Demographic factors, comorbidity, discharge diagnoses and mortality within 30 days were described using data from the Danish National Patient Registry and the Civil Registration System. Cox regression was used to estimate adjusted hazard ratios (aHR) with 95% confidence intervals (CI) for all-cause mortality. RESULTS: A total of 93,295 patients (49.4% men) with a median age of 75 years (interquartile range: 69–82 years), were included. Out of these, 2775 patients (3.0%; 95% CI 2.9–3.1%) died within 30 days after discharge. The 30-day mortality was increased in patients with age 76–85 years (aHR 1.59; 1.45–1.75) and 86+ years (aHR 3.35; 3.04–3.70), male gender (aHR 1.22; 1.11–1.33), a Charlson Comorbidity Index of 1–2 (aHR 2.15; 1.92–2.40) and 3+ (aHR 4.07; 3.65–4.54), and unmarried status (aHR 1.17; 1.08–1.27). Discharge diagnoses associated with 30-day mortality were heart failure (aHR 1.52; 1.17–1.95), respiratory failure (aHR 3.18; 2.46–4.11), dehydration (aHR 2.87; 2.51–3.29), constipation (aHR 1.31; 1.02–1.67), anemia (aHR 1.45; 1.27–1.66), pneumonia (aHR 2.24; 1.94–2.59), urinary tract infection (aHR 1.33; 1.14–1.55), dyspnea (aHR 1.57; 1.32–1.87) and suspicion of malignancy (aHR 2.06; 1.64–2.59). CONCLUSIONS: Three percent had died within 30 days. High age, male gender, the comorbidity burden, unmarried status and several primary discharge diagnoses were identified as independent prognostic factors of 30-day all-cause mortality.